TOP 3 largest TVs. Types of TVs and their differences The best CRT TVs of the past
It's no secret that every year more and more market participants (both manufacturers and consumers) are interested in “flat panel” TVs. Firms are actively transferring intellectual resources and production capacity to the creation of liquid crystal and plasma TV. An increase in the production volume of these High Tech models leads to a decrease in cost, and the circle of potential buyers gradually expands... This is how the flywheel of the “product-money-product” process spins up. This situation could not but affect the situation with traditional picture tube (CRT) televisions. Now CRT models of small (14–21") and medium (25–29") diagonals are competitive due to price. And what about elite TVs with a diagonal of 32–36"? Here the question of choice becomes menacingly categorical. 36 inches is practically the limit for CRT technology. Such devices essentially represent the High End sector of the television world, and in terms of money they are not much different from flat screens PDP and LCD panels (diagonal 32–42 inches) from the lower price category. The TV giants also have another competitor that has claimed the main role in the home cinema - video projectors for $2000–3000 already offer projectors that satisfy the demands of the discerning. movie buffs (see test in September S&V, 2003). However, let’s not forget that top-class CRT televisions are the pinnacle of technological achievements; they contain experience that has been honed by development companies for decades. There are plenty of rationalists among buyers who are not. those who are inclined to invest money in newly created technologies (plasma and crystals are in development); not every consumer is ready to put up with limitations (the projector requires darkening the room). And so many of us are asking the question: what is the potential of large-format CRT televisions, do these giants have the reserves of strength to fight for existence in the era of total miniaturization?
In the current test there are few models, and all are from companies that support the production of 36-inch TVs. In passing, we note that equipment of such a serious level is produced only by the grandees of the AV industry. Let's try to determine the common features of the current participants. Apart from the weight, which reaches 100 kilograms, the main feature is the digital chassis and systems used in the fight for image quality. This is important, because even minor flaws in the picture become noticeable on a meter-long screen. When receiving television broadcasts, digital video signal processing improves quality (for example, a digital comb filter helps separate luminance and color signals). Through the use of digital filtering, effective reduction of color noise is achieved. If the video input of the TV receives a component signal (divided into luminance and color difference components), for example, from a DVD player, with a minimum noise level, then in this case, digital algorithms are tasked with the extremely difficult task of correcting what is seemingly impossible to fix , - flicker of 50-Hz scan and line structure of the image. Increasing the frame rate (the notorious “100 Hz”) or converting interlace to progressive helps out. In addition, depending on the quality and format of the image, different processing algorithms are often required (modern devices have different modes). All this ultimately makes up the portrait of a high-end large-screen TV. However, it’s time to take a closer look at this portrait screen...
Philips 36PW9618
Perhaps the main feature of the 36PW9618/58 model, which sets it apart from other test participants, is its self-sufficiency: a representative of the elite MatchLine series, it is, in essence, a very attractive solution for a home theater, so to speak, “all in one”. The only thing missing for a complete set is a DVD player...
The control buttons located on the top panel are convenient and easily accessible (a solution that has become the hallmark of the company's top models). The universal remote control is capable of controlling five devices of the AV complex. The Compass GUI graphical interface is very ergonomic and, one might say, simply elegant. For example, when setting up a region, a map of Europe appears on the screen, and a dot points to Russia. Additional front connectors are hidden in a deep niche on the side panel, which creates some difficulties when you need to quickly connect, for example, a video camera. The status of an elite model is emphasized by a set of digital image processing technologies. The user can choose the digital algorithm for viewing a specific program: Pixel Plus, 100 Hz Digital Scan or line doubling (progressive scan). I liked the way the Active Control system works - adjusting image parameters depending on ambient lighting conditions. In our opinion, its presence is especially important for theatrical TV. When switching from watching TV programs to showing movies from a DVD or satellite tuner, it would be a good idea to apply some dimming - in this case, Active Control will quickly and accurately reconfigure the entire set of image parameters.
According to the measurements, which are in good agreement with the viewing experience, the model has excellent performance in terms of image clarity and brightness; The detail of the picture is excellent. The device demonstrates its “pictorial” capabilities most effectively in landscape scenes, when the sun-filled space acquires volume and captivates with realism. However, if in bright scenes the color shades are quite natural, then in fragments with low color saturation blue-green tones begin to predominate (at a low brightness level, the color temperature increases; see measurement results). The image from the DVD is distinguished by bright, rich, sometimes overly saturated colors. The presence of digital noise slightly reduces the visual impression. Going through digital correction modes, if it improves the situation, does so only slightly.
The soundtrack is characterized by a large reserve of power. The developers tried to focus on the mid-frequency range to increase speech intelligibility.
Rich digital image processing capabilities, a set of theater decoders, amplifiers and acoustics, as well as convenient controls will be appreciated by supporters of integrated solutions when building a home theater.
Measurements
Color gamut chart
Technical Note
Excellent brightness and color clarity (500 and 150 TVL). The contrast was 32:1. The color gamut is narrowed on the red and green side, while the color temperature of the saturated white field turned out to be equal to 8150K. The color temperature value in fragments of low and medium brightness is overestimated and is about 9000K. The brightness uniformity is not the highest, the relative spread was 57%. The brightness response does not correspond to linear behavior only in the darkest fragments. Color uniformity is one of the best in the test - the difference across the screen field is only 750K. The tuner sensitivity is sufficient for urban reception conditions (–45/–65 dB).
Samsung WS-36Z4HFQ
The design of one of the largest representatives of the Plano model range from Samsung, along with corporate traditions, also carries individual features - the screen is enclosed in an elegant frame, visually distinguishing it from the background of the front panel. Front AV connectors are conveniently located on the side console. We also note the VGA input, which allows you to use the TV as a giant monitor.
Full access to TV control is possible only from the remote control; Using the buttons on the front panel, you can only enter the local menu and adjust the basic image parameters: brightness, contrast, color saturation; adjust the volume of speakers and headphones.
The presence of digital video signal processing systems Digital ProPicture and Total DSP System allows you to significantly adjust the image quality. The TV produces the most saturated, natural and devoid of “jagged” inclined lines image in the Progressive mode, however, in this case the flickering of the frame scan becomes noticeable. Among the design features is a rich set of connectors: in addition to the VGA input, there are three SCARTs (with RGB and S-Video inputs), an input for color difference component signals, connectors for connecting external acoustics and linear audio outputs of the Dolby Pro Logic decoder. The basis of the functional set is digital image processing modes, five gradations of color temperature, image and sound presets, six format adaptation modes, freeze frame, PIP and Multi PIP.
The conclusion that can be drawn based on a multifaceted assessment of image quality is that it is almost always possible to achieve realistic color reproduction by adjusting color saturation and selecting color temperature profiles. At the same time, a colossal reserve of brightness and one of the highest contrast values give the image volume and detail. The situation with noise is somewhat worse: on broadcast programs with a weakened signal level in SECAM, a small color noise is noticeable. When watching video material from DVD, the image is distinguished by good dynamics and rich color shades, and the minimal level of digital artifacts in dynamic fragments adds realism.
The sound picture has a distinct spatial organization, and the bass is well developed. However, there is some harshness at high frequencies, especially at high volumes (apparently due to increased distortion levels).
At a reasonable price, the Samsung WS-36Z4HFQ attracts with its rich picture, functionality and good quality design.
Measurements
Color gamut chart
Technical Note
The TV showed good results in terms of brightness and color clarity - 490 and 140 TVL. The image contrast is one of the highest in the test, 52:1. The color gamut is slightly narrowed on the green side and slightly narrowed in the red area. The device has excellent color uniformity (the spread was only 400K), but the average level was lower than the reference value (about 4200K). The brightness uniformity is average - the relative spread is 48%. Color uniformity is good, the difference between the maximum and minimum color temperature across the screen field was 1110K. The tuner sensitivity is one of the highest in the test (–60/–65 dB).
Sony KV-36HQ100K
Measurements
Color gamut chart
Technical Note
Brightness clarity turned out to be the highest in the test - 510 TVL, while color clarity was average - 120 TVL. The picture contrast of 1:60 is the best in the test. The color gamut is slightly distorted in the red region, but the white coordinates are close to the reference ones. The color temperature in dark areas varies over a wide range from 2000 to 8000K, and in medium and light areas, on the contrary, it is constant. Moreover, the average value for all shades of gray is very close to the reference value - 6700K. Brightness uniformity is not great - the relative difference was 72%. Color uniformity is also not record-breaking - the spread turned out to be 2380K. The tuner pleased with its sensitivity: –58/–65 dB.
How to choose a CRT TV? ">
1. Screen size.
The first thing you need to decide on when choosing a TV is what screen size is optimal for your room. You shouldn’t immediately focus on the large diagonal, as it will be very uncomfortable to watch in a small room. The diagonal size of the TV is indicated in inches, less often in centimeters (domestic TV models). The very name of the TV model contains a reference to the size of its diagonal (for example: Sony KV-29CL10K TV – 29” diagonal). TVs have standard screen sizes. The most common: 14” (37 cm), 20” (51 cm), 21” (54 cm), 25” (63 cm), 29” (72 cm), 32” (81 cm), 34” (87 cm), 36” (92 cm). As the diagonal of the TV increases, its overall dimensions also increase. The depth of televisions with a small diagonal, as a rule, is no less than their diagonal (14” - 27 cm), and for televisions of medium and large diagonals the depth is 47-60 cm. The optimal distance from your place from which you watch TV programs to the screen when watching A 4:3 TV (standard aspect ratio) is 3 to 5 screen diagonals. At the same time, a distance of 3 diagonals is acceptable for 4:3 format TVs with a 100 Hz scan and additional image processing systems, which greatly reduces screen flickering and, accordingly, minimizes eye strain. For 16:9 widescreen TVs, the recommended viewing distance is 2.5-3 screen diagonals. If you are going to put the TV in a niche, you must take into account that there must be a distance between the walls of the niche and the TV body to ensure free air circulation.
TVs 14”-15”. A very large family of televisions. In terms of image quality and functionality, they are very similar to each other, however, more well-known companies, as a rule, equip their TVs with higher-quality components and picture tubes. Therefore, when choosing, first of all, you should pay attention to the design you like, whether this TV has a flat or convex kinescope, the presence of one or two speakers and teletext. Manufacturers can equip them with an indoor antenna, however, the quality of reception with such an antenna is extremely low.
TVs 20”-21”. The most numerous group of televisions. Almost every manufacturer offers a wide selection of TV models of this diagonal, both with a conventional convex and flat screen. Functionally, TVs of this diagonal do not differ much. When choosing, you need to pay attention to the design, the presence of teletext, and the number of speakers. Some TV models have stereo sound and balance adjustment. Most manufacturers consider 20"-21" and large diagonal TVs as stationary and do not equip them with their own antenna, assuming that a cable one will be used.
TVs 25”. They are not in great demand in our country. These TVs vary greatly in their functionality, the presence or absence of stereo sound, and design. The price of these TVs is significantly higher than 21” TVs. In addition, in the model range of televisions of this diagonal there are models with a scan rate of 100 Hz (relevant for CRT televisions). Their cost is often higher than that of 29-inch models with 50 Hz scan. Although these TVs have high-quality stable images, good functionality and stereo sound, they typically lack digital processors to improve picture quality, which prevents them from truly competing with 29-inch TVs in terms of picture quality.
TVs 29” and higher. These TVs have a huge range in their functionality and technical characteristics; many are equipped with digital image processors and 100 Hz scanning, as well as additional speakers to enhance the bass (which, however, still does not make their audio system full-fledged for watching DVDs). In addition, when choosing a large diagonal TV, its appearance is important. Some companies complete their TVs with bedside tables (or supply them additionally).
2. Technologies.
100 Hz technology.
Which is better, 50 or 100 Hz sweep?
According to the current television broadcasting standard, the picture is transmitted in 2 stages: in two half-frames, through a line - first all odd lines, and in the second stage - all even lines. This is called interlaced scanning. Half-frames are transmitted at a frequency of 50 Hz.
Main disadvantages: the “flickering” effect (the human eye notices this flickering frequency) when displaying an image on the screen, in addition, horizontal lines “shake” with a frequency of 25 Hz. This is especially noticeable on a white background and on a large screen.
100 Hz technology. – this is a digital technology that ensures that the screen is updated 2 times more often than with 50 Hz technology, i.e. "half-frames" appear 2 times more often. A video signal presented in digital form provides much greater processing capabilities than an analogue one. For example, you can remember a digitally represented frame of an image and play it back at the right time. This technology allows you to solve the problem of flickering images on the screen. The fact is that with a half-frame (field) changing frequency of 50 (60) Hz, image flickering, especially in bright areas, still remains noticeable.
However, this system is also not without drawbacks: when alternating half-frames first - first - second - second, the transition from odd to even lines occurs with the same frequency of 50 Hz. This is manifested in the shaking of the upper and lower edges of the image details due to the alternation of even and odd lines.
This drawback can be overcome by an improved system called Digital Scan, in which half-frames alternate in the sequence first - second - first - second. In this case, the frequency of changing half-frames with even and odd lines is already 100 Hz, and jitter becomes almost unnoticeable.
In addition, 100 Hz technology has several disadvantages, including digitization of the image and digital loop when objects move quickly. To better convey rapidly changing images, 100 Hz TVs use special digital signal processing technologies, such as Digital Scan with Natural Motion (Philips), Digital Plus (Sony), Digital Mastering and Intelligent Mastering (Thomson), Digital Scan and Super Digital Scan (Panasonic), Full Digital with DMI (Digital Motion Interpolation) system (Loewe) and others. In these systems, using a special algorithm, an intermediate frame is created, which is inserted between the frames from which it is formed. As a result, fast-moving objects on the screen look more natural.
3. Image format.
Today there are two TV screen formats: the traditional, familiar to everyone, 4:3 and the widescreen 16:9 image format.
When choosing a TV format, you must decide what you will mainly watch: If you mainly watch TV shows on TV, watch MPEG4 (DivX) movies or a VCR, then you should buy a 4:3 TV, because its format coincides with the format of television broadcasting. However, when viewing a 16:9 image (for example, DVDs), there will be black bars at the top and bottom of the TV screen (which, most often, can be removed by “cutting off” the edges of the image).
If you are a DVD lover and want to spend your leisure time watching your favorite films, then it makes sense for you to buy a 16:9 TV. Because most DVDs on the market today contain images in 16:9 format. However, we note that television broadcasting in Ukraine does not use a wide format. When watching regular TV programs on a 16:9 TV, there will be unused, black areas at the edges of the screen, i.e. The "effective" diagonal of the image will decrease. On the other hand, such televisions usually provide for an increase in the image size to fill the entire screen, which results in the loss of the upper and lower parts of the image, which, as a rule, are not very informative for television programs. Many wide-screen TVs also use “smart” image enlargement, when the image fills the entire screen, distorting nonlinearly - the central part remains practically unchanged (and it is the most informative), and the periphery of the screen is distorted (the upper and lower parts may shrink slightly, and the side parts - to stretch). It looks strange at first, but then you get used to it.
By the way, widescreen images can be not only 16:9, there is also a fully cinematic format of 2.35:1. When watching DVDs marked "2.35:1", even on 16:9 screens there are black stripes at the top and bottom.
16:9 TVs provide especially great opportunities for creating a home cinema. The viewing angle increases significantly, the perfection of the image in combination with the appropriate audio design allows you to feel full involvement in the events on the screen. Note that the source of a wide-format image can be not only a DVD player: there are satellites that provide broadcasting in a wide format and even with multi-channel Dolby Digital sound.
4. TV sound and power.
When choosing a TV, you should decide what kind of TV you want to have. There are two types of TVs: with mono and stereo sound. In this case, the TV can play stereo or only from an external source or from the air (A2, NICAM) and from an external source. In addition, mono TVs come with one or two speakers. Mono TVs with two speakers imitate stereo sound, but do not separate it into two channels, like stereo. It should be remembered that domestic television broadcasting predominantly works in mono and in this case there will be no effect from stereo sound on the TV. TVs with stereo sound are usually equipped with a large number of additional sound settings.
A number of TVs have built-in Dolby Pro Logic and/or Dolby Digital surround sound decoders. The TV set may include additional speakers, when connected, it is possible to realize 6-channel Dolby Digital sound and, by purchasing an additional DVD player, create a home theater. Nowadays there are even some satellite channels that broadcast with 6-channel Dolby Digital audio. However, in most cases, the source of multi-channel sound is a DVD player. Many TVs are equipped with a Virtual Dolby system instead of Dolby Pro Logic decoders, which allows you to simulate surround sound using a regular stereo system.
Speaker power is an important indicator of the sound quality of a TV; it is measured in watts; the higher the power indicator, the better sound quality you can get.
However, no matter how good the sound of TVs is, it will still be inferior to the sound quality of a home theater system.
5. Additional features.
Quite often a situation arises when interesting programs are broadcast simultaneously on several channels, or, for example, while watching a movie on one channel, you are afraid of missing the beginning of the news or an interesting match on another. At such moments, you want the TV screen to be divided into several parts, which would display different channels. Digital technologies make this possible.
Television designers have developed a technology called Picture in Picture, or PIP for short. This technology allows you to display on the screen, against the background of the main channel, in a small rectangular window, any other channel of your choice, or an image received from an external video source (VCR, video camera, etc.). The soundtrack can be selected for both the main and additional programs. Usually, it is necessary to change the size of the additional picture and its location on the screen. It is also possible to exchange images between the main screen and an additional window by pressing one button on the remote control.
Even inexpensive TV models can be equipped with the simplest single-window PIP (passive PIP). In this case, one TV tuner is used, so in an additional window you can display only programs coming to the TV through a low-frequency input, for example from a VCR, camcorder or DVD. If you are viewing a recording played from a VCR on the main screen, you can follow one of the broadcast programs in a small window.
The capabilities of the simplest PIP system can be expanded by connecting a VCR (or DVD recorder with a TV tuner) to the low-frequency input. In this case, you can additionally output broadcast programs coming through the VCR tuner. If you connect a satellite tuner to your TV, using PIP you can view satellite programs in an additional window.
More expensive TV models may include a PIP unit equipped with its own (second) tuner (active PIP). In this case, in an additional window, or windows, you can view any programs coming to the TV. Many of the TVs with two tuners allow you to simultaneously display 3 - 9, and in widescreen TVs, even 16 windows, with various programs (Multi PIP, Multi Window EX systems and others). Widescreen TVs with a 16:9 screen format can implement the POP (Picture Out of Picture) mode. In this mode, three additional images are inscribed in the free part of the wide screen on the side of the main 4:3 picture, together with it completely filling the area of the TV screen. PAP (Picture and Picture) The screen is divided into two parts, each containing a slightly compressed active image.
PAT (Picture and Text) The screen is divided into two parts: a slightly compressed active image and a full page of text.
6. Connectors for connecting external devices
. If you want to watch videos on your TV from external devices, many questions arise at once. When choosing a TV, it is very important to keep in mind in advance all the devices that you will want to connect to it, not only now, but also in the future, and make sure that your TV is equipped with a sufficient number of necessary connectors. Otherwise, you will only have to regret the wrong choice.
However, TVs have many different connectors, and not everyone can understand them. The user of a TV equipped with every conceivable connector will be faced with another problem - choosing the most correct and best one from the many connection options through these connectors.
The most common (but not the best) standard for connecting additional devices to a TV is a composite signal (RCA, Cinch, “tulip”). It represents the combination of all components containing video information into one signal. It is the composite signal that is obtained at the output of the television tuner (i.e., the receiver of the terrestrial television signal). VCRs, camcorders, DVD players, etc. are equipped with composite video outputs. In fact, it is difficult to find a device that does not have these outputs. The advantages of the composite method are clear - combining signals allows you to obtain the most capacious and convenient signal for transmission, which requires only one wire. However, when the original RGB or component signal is converted to a composite signal, some of the information is lost, and when the TV subsequently converts the composite signal back to RGB, the information cannot be restored. As a result, the resulting image is somewhat worse in quality (although this is not noticeable for small-diagonal TVs). On the other hand, if you are not going to connect a component signal source device (DVD player, etc.) to your TV or your TV is not equipped with a picture tube above 21”, this circumstance should not worry you, and composite connectors will be quite sufficient. The composite connector is made in the form of RCA, and is usually adjacent to the audio connector (one if it is mono, and two if it is a stereo TV). Traditionally, they are indicated together - RCA audio/video. The TV may be equipped with an RCA audio/video input and an RCA audio/video output.
A color image is formed from the primary color signals R G B, that is, the red R, green G and blue B signals, based on the color and brightness data of each point in the image. If you are going to connect an external device that has an RGB output signal to the TV, it is correct to use the RGB input on the TV - this is a convenient way to ensure high-quality signal transmission. On TVs, the RGB input is usually implemented via a SCART connector. The high quality of connecting devices via the RGB input is quite comparable to another connection option - through the component input, which TVs can be equipped with.
Component signals are usually called a combination of a brightness signal (the “Y” component) and color-difference signals indicating the amount of color (the blue component “Pb” and the red component “Pr”). Via component input and RGB, various digital program sources can be connected to the TV: DVD player, digital satellite tuner, computer, digital television decoders, game console, etc. A component input connection is optimal for a DVD player, since all information on DVD discs is contained in component format, and the DVD player is the source of the component signal. Component connectors can be made with “tulips” (RCA) or bayonets (BNC), usually there are corresponding designations Y Pb Pr.
Another standard for connecting to a TV is S-Video (Separate Video, i.e., “separate video”). The S-video connection standard was developed when video players that were superior in quality to the over-the-air signal appeared on the market so that they could be seen as superior to TV programs on the TV screen. We are talking mainly about VCRs and video cameras of S-VHS, Hi8 standards, which use separate brightness and color channels for recording and playback; computer video cards may also contain such an output.
Very interesting is the universal SCART connector, which can allow you to connect signals at once: composite, RGB and stereo sound, and the connection is bidirectional. In addition, a control line is provided between the connected devices. Later versions of SCART provide for the connection of both S-Video and component signals, while the functions of transmitting a composite signal and RGB are limited - the number of pins in the SCART connector is limited. For S-Video and component connections, the TV must have 2 additional SCART connectors installed.
Connecting cables using a SCART connector may not be completely soldered - always check with the seller whether a particular cable will suit you or not.
The TV can also be equipped with separate RCA audio connectors. For example, the RCA audio output (R and L) of a TV allows you to connect to it a stereo system equipped with the appropriate inputs, and reproduce the TV sound through the stereo system, which significantly exceeds the sound power of the TV itself.
Some TVs are equipped with special VGA, or D-Sub, connectors that allow you to connect a computer to them and use them as monitors. However, it should be borne in mind that televisions are not designed to operate continuously for many hours, like monitors, and cannot replace them in this regard. Connecting a TV to a computer can be used, for example, for computer games and the like.
Please note that even if you have connected all the cables correctly, for the connected devices to work together, you may need to further configure the TV inputs, the procedure for which in this case will be described in the operating instructions.
When choosing a TV, pay attention not only to the number of connectors (remember, there should be no less than the number of devices you want to connect), but also to the location of the connectors.
The connectors on the back of the TV are intended for permanent connection of equipment. It is advisable to have as many of them as the number of devices that will be permanently connected to the TV (plus one for the possibility of expanding the system). The connectors on the front (front) or side of the TV are intended for occasional and, as a rule, short-term connection of equipment (video cameras and game consoles). You should not consider them as an option for a permanent connection, since in most cases this is inconvenient and not very aesthetically pleasing.
When selecting equipment, we recommend that you try to ensure that the connectors are of the same type (for example, SCART on both the TV, DVD, and VCR), this will significantly simplify switching and eliminate the problems associated with finding specific cables, adapters, etc. .
7. Pros and cons of CRT TVs.
Advantages:
1. Low cost,
2. Technologies and circuitry developed to the limit,
3. A huge variety of CRT TV models,
4. High image quality,
5. The most natural color rendering,
6. Long service life (up to 15 years).
Flaws:
1. The size of the TV screen is technologically limited (about 38"),
2. Large dimensions and heavy weight of the device,
3. Problems - convergence of rays,
- geometric distortions,
- focusing.
4. Significant influence of magnetic fields on image quality and human health.
8. The most advanced manufacturing companies.
Philips, LG, Panasonic, Sony, Samsung
source of information www.pavleek.3dn.ru
How to provide the TV viewer with the “effect of presence”? You can just make the screen bigger - let it feel almost like being in a movie theater. Or you can show him a three-dimensional picture or literally surround him with an image. Today, in the “110 Years of Television” project, we recall how producers tried to embrace the viewer with a three-dimensional picture.
Bigger size, deeper dive
By increasing the size of the screen, it is really possible to ensure that the viewer has the feeling of an almost real cinematograph: they say, he is not looking at a box with pictures, but is sitting in a cinema.
By the way, this is exactly how the term “home theater” came about: a combination of a large screen TV and stereo sound with several sources placed throughout the room, including the obligatory subwoofer.
But how long can screens be enlarged? The largest CRT TV, according to our information, is the Sony Trinitron PVM-4300U. In the USA it was advertised as 43-inch, in other countries - as 45-inch: in American advertising, by law, it was necessary to indicate not the physical diagonal of the kinescope, but the diagonal of the visible part.
But even 43 inches is simply a huge figure: 109 cm. For comparison: the largest TV made in Belarus cost 950 dollars. This same “Japanese” is almost a third larger, but it cost much more: 40 thousand dollars.
Photo from AvsForum.com
Among projection TVs, the largest is called JVC HD-ILA with a diagonal of 110 inches (2.79 m). OLED TVs have a maximum diagonal of 77 inches (1.96 m), LCD - 108 inches (2.73 m), plasma - 152 inches (3.86 m).
True, televisions with a diagonal of more than two meters are no longer so easy to install in an ordinary apartment: a home theater risks taking up almost half the wall, and for maximum comfort the viewer must sit at the other end of the room or even in the hallway.
And since a simple “mechanical” increase in the diagonal does not lead to the desired effect, then other technologies must be used. For example, to give the image volume.
Stereo television: first broadcasts
Stereo cinema has been around for a hundred years: back in 1915, a test screening of experimental films shot using the anaglyph method with a separation of channels into red and green took place in New York. In the twenties and thirties, stereo films gained popularity, and various methods for producing stereo images appeared. And since you can show a stereo movie, you can try to show a stereo TV show.
The “father” of mechanical television systems, John Baird, experimented with the first three-dimensional television systems in the late 1920s. However, things never went further than experiments. It was only many years later that some television programs began to be broadcast in stereo.
For example, in 1975-1978, the television center in Leningrad, together with the television department of the Leningrad Electrotechnical Institute of Communications, conducted experimental stereo broadcasts; the first such transmission took place on March 25, 1975.
In England in February 1982, another series of the popular science magazine “The Real World” was shown, containing stereo footage made by Philips in the Netherlands. To view this program, you had to use the red-green glasses that came with the program guide. The glasses recreated a black and white image, but in December of the same year they also showed color stereo photography.
Soon, feature films began to be shown “in anaglyph”: the western “Fort T” in the UK and the horror film “Creature from the Black Lagoon” in Portugal.
Still from the stereo film "Creature from the Black Lagoon". Photo from Flickr.com Such programs were broadcast from time to time until the end of the 2000s, but by that time it had already become possible to establish full-fledged stereo television.
And I also put on glasses!
Gradually, several technologies were brought to market: with the use of glasses (anaglyph, polarizing and shutter) and without glasses (autostereoscopic displays).
Anaglyph glasses - the ones with red and blue lenses - are passive systems. However, they don’t make TVs specifically for color glasses, but you can keep such glasses (and they come in both simple cardboard and elegant plastic ones) in case you show an anaglyph stereo broadcast.
Such red-blue glasses are also used in some cinemas; they are also useful for looking at stereo pictures and some computer games.
Photo from Aliexpress.com Another passive system is polarized glasses. This system is also very old: stereoscopic images using polarization have been demonstrated since the late 19th century.
After Edwin Land patented polarizing lenses, the system began to be widely used, and stereo films also appeared. At the beginning of the millennium, with the growing interest in stereo television, polarized glasses became extremely popular. There are mainly two types used: linearly polarized and circularly polarized.
Photo from Mail.ru website Shutter glasses are a system of active glasses, the lenses of which are alternately darkened at a high frequency, thus creating a separate image for each eye.
The first prototypes of shutter glasses have been known since the twenties, although those devices almost a hundred years ago can hardly be called glasses - rather, they were some kind of binoculars. And since the eighties, shutter glasses began to be used in video games.
Samsung has been actively promoting shutter glasses for television since the late 2000s. Such glasses need power and synchronization with the TV.
Photo from DhGate.com Finally, autostereoscopic displays are those screens that show a three-dimensional image without the need for glasses.
Special barrier grids and Fresnel microlenses ensure that each eye sees a column of pixels intended only for it. As a result, the columns for the left eye are visible only to the left eye, and the columns for the right eye are visible only to the right. Of course, if the viewer is sitting in the right place.
The first for real and the first with reservations
In the race for the world's first 3D TV, there were, oddly enough, several winners. Many companies sought to attribute primacy to themselves, as a result, here and there they announced/presented/started selling the “world’s first” surround-image TV.
In the summer of 2008, Hyundai announced that it had begun selling the world's first 3D TV in Japan: the 46-inch model cost approximately $4,860. True, it was immediately said that a little earlier Samsung began selling 3D TVs in the USA, but there, unlike Japan, there are no corresponding TV channels with surround programs.
Indeed: at the CES exhibition in early 2008, Samsung presented the plasma models PAVV Cannes 450 and PAVV Cannes 550. Diagonals are 42, 50 and 58 inches, screen resolution is up to FullHD, and the price is from 1,850 to 4,145 dollars.
Photo from Gizmodo.com In December 2010, Toshiba launched the first TV models that can display three-dimensional images without glasses. The 3D REGZA 12GL1 model with a 12-inch diagonal was priced at $1,900, and the 3D REGZA 20GL1 (20-inch) model was priced at $3,800.
Photo from GadgetReview.com But six months earlier, on April 1, 2010, many sites reported that the Ukrainian enterprise Electron had developed the world's first CRT 3D TV, model 63TK-3D. Allegedly, the 63-inch kinescope displays an image with a “resolution” of 2400 × 1800 pixels. As we know, picture tubes of this size were not produced. But the joke was still funny.
Photo from Gagadget.com When there was no longer any chance to claim the “very first”, companies began to promote the “very first with reservations” surround TVs.
So, in September 2010, Sharp introduced the world's first 3D TV made using Quattron technology (with additional yellow pixels). In November 2010, Philips announced the world's first 3D TV with a “cinema” screen: its aspect ratio was 21:9.
And in February 2011, LG introduced the LW5700 model - the world's first flicker-free 3D TV; This company was also noted for the “world’s first” 3D TV with Full LED Slim technology and the world’s first surround-image TV with ultra-high resolution 3840×2160 pixels.
Horizon presented its first 3D TV at the TIBO-2013 exhibition and priced the 42-inch new product at 7 million rubles, which at the official exchange rate was approximately $800.
The first TV channel to broadcast specialized 3D content for modern TVs was the private Japanese satellite channel DS11. Cable broadcasts of volumetric programs also begin in the spring of 2010.
Since then, several dozen 3D TV channels have been launched around the world (including even a couple of pornographic ones!). About one and a half dozen channels stopped broadcasting.
TV, surround!
Another way to immerse the viewer deeper into the broadcast is to try to “surround” him with the screen as much as possible. A few years ago, companies began offering curved TVs.
In January 2013, at the Consumer Electronics Show in Las Vegas, Samsung and LG simultaneously presented the “world’s first” curved TV.
Both are made using OLED technology, both have a diagonal of 55 inches (~140 cm) and both display images with a resolution of up to 1920x1080 pixels. In May of the same year, LG began accepting pre-orders for the 55EA9800 model, and in July, Samsung announced the start of sales of its KN55S9 model. In both cases, the cost of the TV was 15 million Korean won, or about 13 thousand dollars.
Photo from LesNumeriques.com In September 2013, Sony presented its “world’s first” curved TV - this time the monitor was made using LED TV technology; in other words, it’s a regular LCD TV with LED backlighting. The KDL-65S990A model has a larger screen - 65 inches, and it costs much less than its Korean competitors: only about four thousand dollars.
Photo from Gizmodo.com.au Of course, curved TVs have learned to display 3D content. In April 2013, LG introduced the world's first concave OLED TV with surround image support.
Bent diagonal race
Even two manufacturers are enough to start a “diagonal race,” and since several companies began producing curved TVs in the first year of life, the first releases with the words “the world’s largest curved...” did not have to wait long.
In September 2013, LG showed the world's largest 77-inch curved TV at the IFA exhibition in Berlin; it supports 4K resolution. In December, both LG and Samsung announced that they would show the world's largest 105-inch curved models at CES 2014 in January. And they showed: LG 105UC9 and Samsung 105U9500. And again, the parameters are almost completely identical: aspect ratio 21:9, resolution 5120x2160 pixels.
And already in September - and again at the Berlin IFA exhibition - the Chinese company TCL Multimedia showed a curved TV with a diagonal of 110 inches (almost 280 cm). Its radius of curvature is 7000R - that is, if you place these TVs one next to the other, then over time they will close into a circle with a radius of 7 meters. True, its resolution is lower than that of the Korean giants: 3840x2160 pixels.
Photo from T3me.com Curve on demand
Of course, curved TVs also have their drawbacks. One of the main ones is picture distortion.
If the viewer is alone and sits at a certain distance from the screen strictly along the center line, then he will feel the benefits of a “curved” TV (increased visual width, reduced glare, expanded viewing angles). But if several people are sitting on the sofa, then all of them, except the central viewer, are almost guaranteed to “catch” distortions.
How to be? It’s very simple: when you watch TV alone, let it be curved, and when you watch TV alone, let it be flat. How is this possible? Thanks to not just curved, but bendable TVs.
Back at CES 2014 in January, LG showed a 77-inch bendable TV, and Samsung showed an 85-inch one. Later, in September 2014, at the Berlin IFA exhibition, Samsung also demonstrated a 105-inch bendable TV. Servo drives turn a flat panel into a curved one and back in a few seconds.
Photo from WhoWired.com As they joke on the Internet, curved TVs are a well-forgotten old thing. Only now TVs are concave inward, but before they were curved outward.
TV "Neman", produced since 1960 in Minsk. Photo from the site Old-Cherdak.com.ua The new generation of Samsung SUHD TVs convey images as accurately and realistically as possible. Thanks to advanced quantum dot technology, even the smallest details and dark areas in an image are visible in any lighting conditions.
The idea of transmitting a moving image over a distance captured the minds of many scientists back in the first half of the nineteenth century. However, the main problem that enthusiasts faced was the lack of technical ability to convert a light signal into an electrical signal, which could be transmitted over wires over a considerable distance.
The first device with which it was possible to successfully transmit an image over electric wires can be considered the copying telegraph, patented in 1843 by Alexander Behn. Transferring one monochrome image using it was a complex and time-consuming process. The rectangular frame was tightly packed with parallel thin insulated pieces of wire about an inch long. Then, by moving individual wires, a picture-imprint was formed and the frame was filled with liquid sealing wax. After it hardened, grinding was carried out: on the side where the wires protruded above the general array, until they were stripped, and on the opposite side, the sealing wax was completely removed. Next, a line-by-line scanning of the image was performed with a special moving metal probe, and in a similar way, an image was constructed on the receiving side at the same time.
The copying telegraph turned out to be too complex, slow and expensive a device and did not find any real practical application. Nevertheless, it can well be considered the first step towards the invention of television, since Alexander Behn was the first to present the image in the form of individual dots, and to read and reproduce it he used progressive scanning with time? th synchronization.
The next step on the long path to a modern television was the discovery in 1873 by the English scientist Willoughby Smith of the photoelectric effect - the ability of selenium to change its conductivity under the influence of light. In the next couple of decades, the German Heinrich Hertz and the Russian physicist Alexander Stoletov were engaged in research on the photoelectric effect. One of the practical results of the latter’s work was the invention in 1887 of the “electric eye” - the prototype of the modern photocell.
Parallel O Other discoveries were made in the scientific world that created the preconditions for the invention of television. In 1879, the Englishman William Crookes discovered substances that can glow under the influence of cathode irradiation - phosphors. In 1887, German physicist Karl Braun introduced the first cathode ray tube - the prototype of the kinescope.
Mechanical TV
In the first half of the eighties of the nineteenth century, the German engineer Paul Nipkow created a device in which the problem of progressive scanning and synchronization of the transmitter and receiver was solved in an extremely simple and elegant way. Its removal device contained a rotating disk of opaque material with several dozen holes (in some models the number of holes reached two hundred), which were located in a diverging spiral. On one side of the rotating disk there was an illuminated image, and on the other there was a single photocell that read the intensity of the light flux passing through the moving holes.
Nipkow’s TV had the same disk, but instead of a photocell, a powerful neon lamp was installed, the light of which was regulated by a signal received from the “TV camera.” As a result, a blurry, but still quite visible image was projected onto a small screen.
British mechanical televisions Baird and Plessey
With minor modifications, mechanical televisions were produced until the end of the thirties of the twentieth century, and only the spread of televisions with cathode ray tubes led to their disappearance.
The main disadvantages of mechanical TVs, compared to CRT models, were insufficient reliability due to the complexity of the mechanical part, as well as, of course, significantly lower image quality. Nevertheless, it was with the help of a mechanical television system that, for the first time in the world, a photograph of a person’s face was transmitted over a distance in a quality sufficient for its recognition.
CRT era
After Brown created the simplest cathode ray tube, scientists around the world explored the possibilities of its practical application. In 1907, the Russian scientist Boris Rosing received a patent called “Method of electrical transmission of images over a distance,” and already in 1911 he was the first to transmit and receive images of the simplest geometric figures at a distance, as well as display them using a television system on the cathode -ray tube. The images were still, and they were captured using a Nipkow disk.
On July 26, 1928, the young inventor Borisov Grabovsky in Soviet Tashkent was the first to transmit a moving image using radio waves and reproduce it on the screen of a cathode ray tube. Many researchers (including American ones) consider this event to be the birth of modern television.
In parallel with Grabovsky, Russian emigrant Vladimir Zvorykin worked on solving the problem of using cathode ray tubes to obtain images in the United States. Back in 1923, he filed a patent application for an electronic television system, but was able to obtain a patent only in 1938. By that time, he had already developed and created in 1929 a high-vacuum receiving cathode ray tube, which he called a kinescope. And in 1931, also a transmitting tube - an iconoscope. In 1933, at the annual conference of the largest American Society of Radio Engineers, Zvorykin presented a fully completed electronic television broadcasting system. For this reason, some researchers give him the palm in the invention of television.
The world's first serial TV
In 1936, in his own RCA research laboratory, Zworykin presented the first television, which was no longer an experimental model, but was completely suitable for mass use. And in 1939, production of the first serial television with a cathode ray tube, called RCS TT-5, began. It had a tiny five-inch screen housed in a bulky and heavy case, but it provided reliable reception and was therefore quite popular.
KVN-49 - the legendary Soviet TV
The first Soviet mass television, which was produced between 1949 and 1967, was the famous KVN-49. Its name is an abbreviation of the names of the creators (Kenigson, Varshavsky and Nikolaevsky), and a television game with the same name appeared much later and received its name due to the coincidence with the name of the legendary TV. KVN-49 had a small screen measuring 180 mm diagonally (the kinescope itself was round and was simply covered with a rectangular frame with rounded edges). To increase the size of the image, a large lens was used, located directly in front of the screen. In order not to make the TV too heavy and expensive, this lens was not solid, but was a specially shaped flask filled with distilled water.
Until the early fifties of the twentieth century, laboratories around the world struggled to develop color television systems. Back in 1928, the same Zworykin described the basic principles of color television broadcasting and methods of decomposing the visible spectrum into its components. However, practical implementation took place only in 1954 - the RCA laboratory presented the first color television with a fifteen-inch screen. However, the widespread adoption of color television was delayed for decades due to serious problems with the organization of color television broadcasting. For this reason, until the end of the seventies, the mass production of black and white devices continued (in the USSR until the early nineties).
First mass-produced color TV Westinghouse H840CK15
Throughout the second half of the twentieth century, the world's leading manufacturers of consumer electronics made serious efforts to improve the televisions themselves. The size of screens grew (there were models with a screen diagonal of 36 inches), overall dimensions decreased, and special means were used to achieve a flat screen (first with the help of leveling lenses, and then they actually moved on to producing picture tubes with a flat front part and a complex system for adjusting the electron beam). Much attention was paid to improving the sound - expensive models provided quality close to the sound of Hi-Fi stereo systems.
Toshiba 36SW9UR - one of the largest CRT TVs
Nevertheless, by the end of the millennium it became obvious that CRT TV models were doomed and would soon completely disappear from world markets.
Projection, plasma, liquid crystals
Even at the dawn of the development of television, developers tried to increase the size of the visible picture. The lens in the KVN-49 TV is only the most obvious solution. The creators of projection systems took a different path. In the fifties, interesting solutions were produced in the Soviet Union and the West that made it possible to obtain a television image measuring more than a meter diagonally. These devices were a system of a high-brightness transmitting kinescope, an optical system and a screen on which the image was projected.
The sixties - the first attempts to get a big TV screen
Due to the excessively high cost, such television projectors were mainly used in clubs, cafes and other public institutions. They were not widely used, but in the eighties, projection televisions were created on the same principle, which at relatively affordable prices made it possible to watch television programs on a screen with a diagonal size of 25-45 inches.
Projection TV - large screen and considerable dimensions
Compared to conventional TVs, projection TVs had a number of significant disadvantages. Firstly, the sector for comfortable viewing was quite narrow. Secondly, due to the fact that the luminosity of the picture tubes was too high, it was recommended to watch only dynamic films on these TVs - the frozen picture literally burned through the phosphor on the surface of the picture tube and image artifacts appeared on the screen, interfering with viewing. Thirdly, the high power of picture tubes and backlight lamps led to the release of a large amount of heat and the need to install special cooling systems, which led to an increase in the level of extraneous noise. And lastly, projection televisions were quite large devices. But with all these shortcomings, it was only in the new millennium that they were supplanted by new technologies - plasma and liquid crystal.
Modern plasma TV with a diagonal of 51 inches
In 1993, the Japanese Fujitsu began selling a color plasma TV with a diagonal of 21 inches, and in 1995 it already introduced a model with a screen size of 42 inches, unimaginable at that time. At the same time, the picture quality was close to the best models of CRT televisions, and the thickness of the television was about 10 cm. Plasma models were only prevented from instantly capturing the entire market of television receivers by their too high cost - there were not many people willing to shell out thousands of dollars for a television. And yet, by the end of the millennium, various models of plasma devices were already presented in all retail chains dealing with consumer electronics.
B 198 7 The Japanese company Sony introduced the first color liquid crystal display with a diagonal of three inches. For ten long years, technologies for the production of fairly inexpensive and high-quality LCD matrices have been developed, and in 1998 several manufacturers introduced televisions with fifteen-inch screens. The first models could not boast of good picture quality in dynamic scenes due to the rather large inertia of switching each pixel. Nevertheless, the development of technology has led to a sharp reduction in the cost of matrices, an increase in size and an improvement in their parameters, and already in the early tenths of the new millennium, liquid crystal televisions completely replaced the more expensive plasma ones from the market.
Television and modernity
In March 2014, a significant event occurred. One of the pioneers and leaders in the global consumer electronics market, Panasonic, has stopped producing and selling plasma TVs. Today, only South Korean Samsung and LG continue to produce plasma panels, but experts predict that this trend will be curtailed in their country in the coming years. Thus, in the near future, only various models of LCD TVs will remain on the world market.
However, the average consumer has no reason to be upset. The matrices of modern LCD televisions are superior to any other types of television screens in their characteristics. The maximum screen size is one hundred and ten inches diagonally (there is even a street version with a diagonal size of 201 inches, but since it has a composite matrix, we will not consider it a leader). Excellent color rendering, brightness and contrast, minimal power consumption, minimal weight and dimensions, 4K matrix resolution, full 3D - and all this at a lower cost than any other technology.
The largest (at the beginning of 2014) LCD TV
All of the above is the reason that LCD TVs have now supplanted all their competitors. However, there is every reason to believe that such hegemony will not last very long. Various laboratories around the world are currently developing holographic three-dimensional television, which will provide a full immersive viewing experience without the need to use 3D glasses. So it is quite possible that in a decade or two we will be watching (or is it better to use the word “present”?) television programs without any screens at all, perceiving the image simply hanging in the air in front of the viewer.
Briefly about the article: Televisions based on picture tubes and liquid crystals, plasma and projection - today we will look at all known types of these “pets”, because the TV not least determines how pleasant it will be to watch your favorite films.
The story of four "boxes"
Types of modern TVs
Not so long ago, the problem of choosing a TV was not a problem for most domestic consumers. Soviet industry produced two or three models for more than two hundred million people, and everyone was extremely happy. Today, hundreds of different televisions dazzle your eyes. Modern “boxes” differ not only in price and diagonal size, but also in the principle of image formation. Dark forest? So let's find clear guidelines in it.
One gun - one screen
Televisions based on picture tubes (CRT - cathode ray tubes) appeared a long time ago, which is why they are the most common today. The operating principle of such “boxes” is extremely simple. The back side of the screen is covered with a phosphor (when this substance is bombarded with charged particles, it begins to glow). An electron beam passes through it line by line, “igniting” multi-colored phosphor dots.
The problem is that only a few lines are lit on the screen in one very short period of time. We see the whole picture only because of the peculiarities of our vision. The subconscious still “understands” such deception, and we have to keep the components of the image in memory. That is, even relaxing in front of such a TV, we tense up a little.
For a long time, CRT TV screens were convex. The engineers managed to get a “plain” instead of a “hill” about ten years ago. Today, only the smallest and cheapest TVs are equipped with non-flat screens. By the way, price is one of the most significant advantages of CRT models. Such TVs have now finally moved into the category of inexpensive solutions for people on a limited budget. This even applies to models from famous brands, including Sony , Philips And Panasonic .
Another advantage is that CRT technology has been refined to its limits. Improving it is like reinventing the wheel or editing a classic novel. This means that almost all CRT TVs are equally good. The quality of the CRT picture is highly satisfactory. The kinescope is naturally endowed with fast response, good contrast and natural color. If you add a reasonable price and long service life to the list of advantages, you get a completely worthy candidate for purchase.
CRT TVs also have disadvantages. Remember that the subconscious reveals the deception about the whole image on the screen? So, if you come close to the TV and look closely, your eyes will catch the flickering of the picture. Still, the change of personnel is not so fast as to go completely unnoticed. This problem can be partly solved by purchasing a high-quality TV with a frame scan of 100 Hz (fortunately, the majority of them are now). The image on it is updated 100 times per second, which significantly reduces eye fatigue.
In addition, the “kinescope” image has such problems as poor convergence of rays (can manifest itself in a slight “iridescence” of objects), imperfect focusing (the picture loses clarity), as well as noticeable geometric distortions (a straight line looks curved).
We are so used to large TVs that we design the furniture arrangement in the room taking into account the “hefty black TV box”. But this is a drawback. Yes, yes, the TV can be smaller and lighter, and in general it can be hung on the wall. But, of course, not CRT. These are destined to live out their lives “on the floor.”
The conclusion regarding CRT TVs is the following: if you are strapped for budgetary funds (like our government), opt for the good old CRT “box”. It will become a rare item no sooner than in seven or eight years.
Picture from gas
A short lesson in physics: plasma is the fourth state of matter (there are also liquid, solid and gaseous, in case anyone doesn’t know). It is a fully or partially ionized gas, where the densities of positive and negative charges are approximately the same.
Why do we need to know this? For a better understanding of the operating principles of plasma TVs. After all, today they can increasingly be found on store shelves and in the living rooms of middle-income families. A plasma screen consists of two glass panels, between which there are many tiny cells filled with an inert gas - neon or xenon. Each dot on the display consists of three separate cells coated with red, green or blue phosphor.
Under the influence of an electric current, the gas inside the pixels turns into plasma and begins to emit ultraviolet rays. UV radiation causes the phosphor to glow. The longer the cell glows, the greater the brightness. In this case, the brightest points may not go out at all, and the dark ones simply do not light up. There is flicker in the image, but it is not noticeable to our eyes.
The advantages of “plasma” are obvious: a perfectly flat screen of small thickness, a huge diagonal (can reach two to three meters), bright and rich colors, no problems with focusing and convergence of beams, a relatively long service life, good viewing angles (colors are distorted when viewed from the side insignificant).
Meanwhile, the technology for producing “plasma” itself is very complex. Therefore, few people are engaged in the manufacture of such screens. Plasma TV manufacturers include the following: joint venture Fujitsu And Hitachi , NEC , Pioneer , LG And Samsung . All. Not much, right?
Well, now a few words about those very ones that you cannot live without - shortcomings. The first is the price is too high. Many plasma TVs cost no less than a car. The second is high “gluttony.” Powering a 42-inch panel requires at least 350 W. CRT TVs are noticeably more economical.
For those who like to pause the player in the middle of watching a movie and go about their business for a long time, “plasma” is not the best choice. Due to the peculiarities of the phosphor coating, when a static image is displayed for a long time, the glow intensity of individual pixels noticeably decreases. That is, over time, the screen brightness may decrease. In addition, due to its impressive weight (30-70 kg), hanging a plasma TV on the wall is quite difficult. But it is possible. Otherwise, why would it be so thin?
It is worth distinguishing between plasma panels and plasma TVs. Otherwise, by paying several thousand conventional units, you can get a “TV” to which you can’t even connect a television cable. Yes, that’s right: to receive TV programs on your plasma panel you need a TV tuner. If you don't have it, you'll have to buy it separately.
Lately there has been a lot of talk about high definition television ( HDTV - High Definition TV). This highest clarity is achieved due to the large number of dots that form the image. So, modern plasma TVs for the most part have sufficient resolution (that is, the number of dots that form the picture) to display a new type of signal without distortion. At the same time, they are well suited to modern television standards.
Liquid image
Liquid crystal screen technology ( LCD - Liquid Crystal Display) has been around for several decades. The most natural LCD boom began in the late nineties of the last century and continues to this day. Today, more than half of computers are purchased with LCD monitors. Laptops have also been equipped with them for the last 15 years. The only thing left to do is to oust CRT TVs from living rooms.
What are the benefits of LCD TVs? Let's turn to theory. A layer of liquid crystals is located between two transparent panels made of film or very pure and sodium-free glass. Under the influence of an electromagnetic field, crystals change the polarization axis of light passing through them. As a result, one cell can change its value from maximally transparent (white) to opaque (black). All intermediate values are shades of gray. To get a color image, just apply color filters to the cells. Thin-film transistors control the “transparency” of pixels ( TFT - Thin Film Transistor), which are sprayed onto the screen in a special way. The number of thin film transistors can be in the millions. The process of creating an LCD screen is quite complex, so it is not surprising that in the early days of their existence, LCD displays were more expensive than the most powerful computers.
With LCD TVs the situation is somewhat more complicated. They began to appear on the market relatively recently. Previously, the biggest problem was the inability to create large LCD screens - the largest ones barely reached a diagonal of 30 inches. But modern technologies make it possible to make screens up to 60 inches in size. On the other hand, one important advantage follows from this disadvantage. Not only large LCD TVs are produced, but also small ones, with a diagonal of 15-17 inches. This trick will not work with plasma ones. And there is no need to cover half the wall in the kitchen with a TV screen. A thin and elegant LCD TV will be much preferable.
LCD TV electronics constantly struggle to bring image clarity to an acceptable level. The resolution of liquid crystal matrices is strictly fixed, since the number of cells cannot be reduced or increased. But the video signal often does not match the resolution of the TV. In this case, the image has to be scaled, which inevitably leads to distortion.
In general, LCD TVs are gradually becoming “adult”, and not only in size. The picture is more and more pleasing every day, getting closer to ideal. The weight of such TVs is quite small: 24-inch models usually weigh no more than 13 kg. Energy consumption is negligible. The price is almost always reasonable.
And one warrior in the field
There is another type of TV - projection. Outwardly, they are similar to picture tubes, but their screen diagonal is usually much larger. Inside the body of such a “box” is hidden a powerful lamp that projects an image onto a white screen. Between the screen and the lamp there are a large number of components that form and improve the image.
There are two types of projection TVs. Some are based on cathode ray tubes, others are based on liquid crystals. In the first case, three small picture tubes (for red, green and blue colors) are hidden inside the case, the rays of each of which travel a long way through a system of prisms, lenses and mirrors. The resulting image is projected onto the screen. Such TVs, like CRT models, have a disadvantage with the screen refresh rate: it can be either 50 Hz or 100 Hz.
Liquid crystal projection televisions contain either one three-color LCD matrix or three (one each for red, green and blue). The formed image is illuminated by a lamp, then passes through a complex system of lenses and hits the screen. This type is preferable to the CRT version. Projection LCD TVs weigh less, have no geometry issues, and boast high resolution (meaning high definition).
Often the lamp that provides the backlight gets very hot, so projection TVs are equipped with a fan for cooling. So don't be surprised if you suddenly hear some noise in the room - this is the TV cooling down.
| Bourgeois option |
There is also one subtype of projection TVs. It is based on technology DLP (Digital Light Processing- digital light processing), which was developed and patented by the company Texas Instruments in 1996. In such TVs, a fully completed optical-mechanical module is installed, which contains special DMD-chips (they consist of a huge number of micromirrors) that process the image and project it onto the screen. From one to three such chips can be installed. Of course, it's best when there are three of them. The image in this case is of the highest quality. There is only one problem - the price is not at all affordable: for a TV with three chips you will have to pay more than tens of thousands of American money, while single-chip models can be found for about $3,000. The main advantages of DLP TVs include good contrast, accurate color reproduction, high definition and brightness. At the same time, micromirrors do not have the effect of illumination of neighboring pixels, so such TVs are excellent for displaying any drawings where there are a large number of thin lines in the picture. But the lifetime of the backlight lamp is usually short. And one more thing: these TVs use a color drum, so an unpleasant rainbow effect is often visible on the screen. DLP devices are strictly not recommended for viewers who are sensitive to this effect. |
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“So what should I choose?” - you ask. The answer is simple: it all depends on the funds you allocated for the purchase of a new TV. If money is tight, you should take a closer look at a 100 Hz CRT TV. It will provide acceptable picture quality and will last for decades. The only “but” is that the large size can become a problem when installing such a “box”.
Buying an LCD TV can be no less profitable. The main advantages of this option are high image clarity, compactness and enviable lightness. It makes sense to buy plasma and projection TVs if you want to get not just a big, but a huge screen. Today, a 50-inch projection TV is cheaper than a similarly sized LCD. The same applies to plasma. But such giants are unlikely to be suitable for the kitchen and bedroom.
