Trinitron
Encyclopedia
Trinitron is Sony
's brand name for its line of aperture grille
based CRTs
used in television set
s and computer display
monitors. One of the first truly new television systems to enter the market since the 1950s, the Trinitron was announced in 1966 to wide acclaim for its bright images, about 25% brighter than common shadow mask
televisions of the same era. Constant improvement in the basic technology and attention to overall quality allowed Sony to charge a premium for Trinitron devices into the 1990s.
Patent protection on the basic Trinitron design ran out in 1996, and it quickly faced a number of competitors at much lower prices. Sony responded by introducing their flat-screen FD Trinitron designs (WEGA), which maintained their premier position in the market into the early 2000s. However, these designs were surpassed relatively quickly by plasma and LCD designs. Sony removed the last Trinitron televisions from their product catalogs in 2006, and ceased production in early 2008. Video monitors are the only remaining Trinitron products being produced by Sony, at a low production rate, although the basic technology can still be found in downmarket televisions from 3rd parties.
The name Trinitron was derived from trinity
, meaning the union of three, and tron from electron tube, after the way that the Trinitron combined the three separate electron guns of other CRT designs into one.
") that rotated in front of an otherwise conventional black and white television tube. Because they broadcast separate signals for the different colors, all of these systems were incompatible with existing black and white sets. Another problem was that the mechanical filter made them flicker unless very high refresh rates were used. In spite of these problems, the United States Federal Communication Commission selected a sequential-frame 144 frame/s standard from CBS
as their color broadcast in 1950.
RCA
worked along different lines entirely, using the luminance-chrominance system. This system did not directly encode or transmit the RGB signals; instead it combined these colors into one overall brightness figure, the "luminance
". Luminance closely matched the black and white signal of existing broadcasts, allowing it to be displayed on existing televisions. This was a major advantage over the mechanical systems being proposed by other groups. Color information was then separately encoded and folded into the signal as a high-frequency modification to produce a composite video
signal – on a black and white television this extra information would be seen as a slight randomization of the image intensity, but the limited resolution of existing sets made this invisible in practice. On color sets the signal would be extracted, decoded back into RGB, and displayed.
Although RCA's system had enormous benefits, it had not been successfully developed because it was difficult to produce the display tubes. Black and white TVs used a continuous signal and the tube could be coated with an even deposit of phosphor. With Valensi's system, the color was changing continually along the line, which was far too fast for any sort of mechanical filter to follow. Instead, the phosphor had to be broken down into a discrete pattern of colored spots. Focusing the right signal on each of these tiny spots was beyond the capability of electron gun
s of the era, and RCA's early experiments used three-tube projectors, or mirror-based systems known as "Triniscope
".
. The shadow mask consists of a thin sheet of steel with tiny holes photo etched
into it, placed just behind the front surface of the picture tube. Three guns, arranged in a triangle, were all aimed at the holes. Stray electrons at the edge of the beam were cut off by the mask, creating a sharply focused spot that was small enough to hit a single colored phosphor on the screen. Since each of the guns was aimed at the hole from a slightly different angle, the spots of phosphor on the tube could be separated slightly to prevent overlap.
The disadvantage of this approach was that for any given amount of gun power, the shadow mask filtered out the majority of the energy. To ensure there was no overlap of the beam on the screen, the dots had to be separated and covered perhaps 25% of its surface. This led to very dim images, requiring much greater electron beam power in order to provide a useful picture. Moreover, the system was highly dependent on the relative angles of the beams between the three guns, which required constant adjustment by the user to ensure the guns hit the correct colors. In spite of this, the technical superiority of the RCA system was overwhelming compared to the CBS system, and was selected as the new NTSC standard in 1953. The first broadcast using the new standard occurred on New Year's Day in 1954, when NBC broadcast the Tournament of Roses Parade
.
In spite of this early start, only a few years after regularly scheduled television broadcasting had begun, consumer uptake of color televisions was very slow to start. The dim images, constant adjustments and high costs had kept them in a niche of their own. Low consumer acceptance led to a lack of color programming, further reducing the demand for the sets in a chicken or the egg situation. In the United States in 1960, only 1 color set was sold for every 50 sets sold in total.
, Sony's president and co-founder, steadfastly refused to develop a system based on RCA's shadow mask design, which he considered technically deficient. He insisted on developing a unique solution.
In 1961 a Sony delegation was visiting the IEEE trade show in New York City
, including Ibuka, Akio Morita
(Sony's other co-founder) and Nobutoshi Kihara
, who was promoting his new CV-2000
home video tape recorder
. This was Kihara's first trip abroad and he spent much of his time wandering the trade floor, where he came across a small booth by the small company Autometric
. They were demonstrating a new type of color television based on the Chromatron
system, which used a single electron gun and a mask of thin wires instead of a shadow mask. The resulting image was far brighter than anything the RCA design could produce, and lacked the convergence problems that required constant adjustments. He quickly brought Morita and Ibuka to see the design, and Morita was "sold" on the spot.
Morita arranged a deal with Paramount Pictures
, who was paying for Chromatic Labs' development of the Chromatron, taking over the entire project. In early 1963 Senri Miyaoka was sent to Manhattan to arrange the transfer of the technology to Sony, which would lead to the closing of Chromatic Labs. He was unimpressed with the labs, describing the windowless basement as "squalor". The American team was only too happy to point out the serious flaws in the Chromatron system, telling Miyaoka that the design was hopeless. By September 1964, a 17 inch prototype had been built in Japan, but mass-production test runs were demonstrating serious problems. Sony engineers were unable to make a version of Chromatron that could be reliably mass produced.
When sets were finally made available in late 1964, they were put on the market at a competitive 198,000 yen ($550), but cost the company over 400,000 yen to produce. Ibuka had bet the company on Chromatron and had already set up a new factory to produce them with the hopes that the production problems would be ironed out and the line would become profitable. After several thousand sets had shipped the situation was no better, while Panasonic
and Toshiba
were in the process of introducing sets based on RCA licenses. By 1966 the Chromatron was breaking the company financially.
on the screen. He also saw General Electric
's "Porta-color" design, using three guns in a row instead of a triangle, which allowed a greater portion of the screen to be lit. His report was cause for concern in Japan, where it seemed Sony was falling ever-farther behind the U.S. designs. They might be forced to license the shadow mask system if they wanted to remain competitive.
Ibuka was not willing to give up entirely, and had his 30 engineers explore a wide variety of approaches to see if they could come up with their own design. At one point Yoshida asked Senri Miyaoka if the in-line gun arrangement used by GE could be replaced by a single gun with three cathode
s; this would be more difficult to build, but be lower cost in the long run. Miyaoka built a prototype and was astonished how well it worked, although it had focussing problems. Later that week, on Saturday, Miyaoka was summoned to Ibuka's office while he was attempting to leave work to attend his weekly cello practice. Yoshida had just informed Ibuka about his success, and the two asked Miyaoka if they could really develop the gun into a workable product. Miyaoka, anxious to leave, answered yes, excused himself, and left. That Monday Ibuka announced that Sony would be developing a new color television design, based on Miyaoka's prototype. By February 1967 the focusing problems had been solved, and because there was a single gun, the focusing was achieved with permanent magnets instead of a coil, and required no after manufacturing manual adjustments.
During development, Sony engineer Akio Ohgoshi introduced another modification. GE's system improved on the RCA shadow mask by replacing the small round holes with slightly larger rectangles. Since the guns were in-line, their electrons would land onto three rectangular patches instead of three smaller spots, about doubling the lit area. Ohgoshi proposed removing the mask entirely and replacing it with a series of vertical slots instead, lighting the entire screen. Although this would require the guns to be very carefully aligned with the phosphors on the tube in order to ensure they hit the right colors; with Miyaoka's new tube this appeared possible. In practice this proved easy to build but difficult to place in the tube – the fine wires were mechanically weak and tended to move when the tubes were bumped, resulting in shifting colors on the screen. This problem was solved by running fine tungsten wires across the grille horizontally to keep them in place.
The combination of three-in-one electron gun and the replacement of the shadow mask with the aperture grille
resulted in a unique and easily patentable product. Officially introduced by Ikuba in April 1968, the original 12 inch Trinitron had a display quality that easily surpassed any commercial set in terms of brightness, color fidelity, and simplicity of operation. The tube was also nearly flat vertically, a side-effect of the vertical wires in the aperture grille, which gave it a unique and appealing look. It was also all solid state
, with the exception of the picture tube itself, which allowed it to be much more compact and cool running than designs like GE's Porta-color. (At least some Trinitron faceplates were actually toroidal segments, with a vertical-plane radius of curvature much larger than that for the horizontal plane. Observing bright reflections on the surface confirms this.)
Ikuba ended the press conference by claiming that 10,000 sets would be available by October, well beyond what engineering had told him was possible. Ikuba cajoled Yoshida to take over the effort of bringing the sets into production, and although Yoshida was furious at being put in charge of a task he felt was impossible, he finally accepted the assignment and successfully met the production goal. The KV-1210 was introduced in limited numbers in Japan in October as promised, and in the U.S. as the KV-1210U the following year.
In spite of Trinitron and Chromatron having no technology in common, the shared single electron gun has led to many erroneous claims that the two are similar, or the same.
Despite the statement above claiming that there were no valves inside Trinitron TV sets, for a brief period in the United Kingdom
between 1969 and 1971/72, the KV-1320UB was fitted with 3AT2 valves for the extra high tension
(high voltage). Later on, the KV-1320UB was redesigned internally and externally to become all solid-state. Despite containing vacuum tubes, the first version of the KV-1320UB was promoted as being all solid-state. The later version of this model is identified as having no wooden outer-shell. These early color sets intended for the UK market had a PAL decoder that was different from those invented and licensed by Telefunken
of Germany
, who invented this color system. The decoder inside the UK-sold Sony color Trinitron sets, from the KV-1300UB to the KV-1330UB had an NTSC
decoder adapted for PAL
. The decoder used a 64 microsecond delay line to store every other line, but instead of using the delay line to average out the phase of the current line and the "remembered" line (as with "Deluxe PAL"), it simply repeats the same line twice. Any phase errors can then be compensated for by using a Tint control on the front of the set.
for the Trinitron in 1973. On his 84th birthday in 1992, Ibuka claimed the Trinitron was his proudest product.
New models quickly followed. Larger sizes at 19" and then 27" were introduced, as well as smaller including a 7" portable. In the mid-1980s a new phosphor coating was introduced that was much darker than earlier sets, giving the screens a black color when turned off, as opposed to the earlier light grey. Early models were generally packaged in silver cases, but with the introduction of the darker screens Sony also introduced new all-black cases, following a similar change in color taking place in the hi-fi world. This line expanded with 32", 35" and finally 40" units in the 1990s.
In 1980 Sony introduced the "ProFeel" line of prosumer component televisions, consisting of a range of Trinitron monitors that could be connected to standardized tuners. The original lineup consisted of the KX-20xx1 20" and KX-27xx1 27" monitors (the "xx" is an identifier, PS for Europe, HF for Japan, etc.) the VTX-100ES tuner and TXT-100G TeleText decoder. They were often used with a set of SS-X1A stereo speakers, which matched the grey boxy styling of the suite. The concept was to build a market similar to contemporary stereo equipment, where components from different vendors could be mixed to produce a complete system. However, a lack of any major 3rd party components, along with custom connectors between the tuner and monitors, meant that the systems were never really mixable. They were popular high-end units, however, and found a strong following in production companies where the excellent quality picture made them effective low-cost monitors. A second series of all-black units followed in 1986, the ProFeel Pro, sporting a space-frame around the back of the trapezoidal enclosure that doubled as a carrying handle and holder for the pop-out speakers. These units were paired with the VT-X5R tuner and optionally the APM-X5A speakers.
Sony also produced lines of Trinitron professional studio monitors, the PVM (Pro Video Monitor) and BVM (Broadcast Video Monitor) lines. These models were packaged in grey metal cubes with a variety of inputs that accepted practically any analog format. They originally used tubes similar to the ProFeel line, but over time they gradually increased in resolution until the late 1990s when they offered over 900 lines. When these were cancelled as part of the wider Trinitron shutdown in 2007, professionals forced Sony to re-open two of the lines to produce the 20 and 14 inch models.
Among similar products, Sony produced the KV-1311 monitor/TV combination. It accepted NTSC-compatible video from Amiga
computers as well as analog broadcast TV. Along with its other functions, it had video and audio inputs and outputs as well as a wideband sound-IF decoded output. Its exterior looks much like the monitor illustrated here, with added TV controls.
By this time, Sony was well established as a supplier of reliable equipment; it was preferable to have minimal field failures instead of supporting an extensive service network for the entire USA.
Sony started developing the Trinitron for computer monitor use in the late 1970s. Demand was high, so high that there were examples of 3rd party companies removing Trinitron tubes from televisions to use as monitors. In response, Sony started development of the GDM (Graphic Display Monitor) in 1983, which offered high resolution and faster refresh rates. Sony aggressively promoted the GDM and it became a standard on high-end monitors by the late 1980s. Particularly common models include the Apple Inc. 13" model that was originally sold with the Macintosh II
starting in 1987. Other well known users included Digital Equipment Corporation
, IBM
, Silicon Graphics
, Sun Microsystems
and others. Demand for a lower cost solution led to the CDP series. In May 1988 they introduced the high-end 20 inch DDM model (Data Display Monitor) with a maximum resolution of 2,048 by 2,048, which went on to be used in the FAA's Advanced Automation System air traffic control
system.
These developments meant that Sony was well placed to introduce high-definition televisions (HDTV). In April 1981 they announced the High Definition Video System
(HDVS), a suite of MUSE
equipment including cameras, recorders, Trinitron monitors and projection TVs.
Sony shipped its 100 millionth Trinitron screen in July 1994, 25 years after it had been introduced. New uses in the computer field and the demand for higher resolution televisions to match the quality of DVD
when it was introduced in 1996 led to increased sales, delivering another 180 million units in the next decade.
Sony's patent on the Trinitron display ran out in 1996, after 20 years. After the expiration of Sony's Trinitron patent, manufacturers like Mitsubishi
(whose monitor production is now part of NEC Display Solutions) were free to use the Trinitron design for their own product line without license from Sony although they could not use the Trinitron name. For example, Mitsubishi's are called Diamondtron. To some degree the name Trinitron became a generic term referring to any similar set. At least some Diamondtron CRT faceplates are spherical sectors; reflections of such objects as ceiling light fixtures are reduced in size and do not change shape regardless of where they appear.
Sony responded with the FD Trinitron, which used computer controlled feedback systems to ensure sharp focus across a flat screen. Initially introduced on their 27, 32 and 36 inch models in 1998, the new tubes were offered in a variety of resolutions for different uses. The basic WEGA models supported normal 480i signals, but a larger version offered 16:9 aspect ratio
s. The technology was quickly applied to the entire Trinitron range, from 13 to 36 inch. High resolution versions, Hi-Scan and Super Fine Pitch, were also produced. With the introduction of the FD Trinitron, Sony also introduced a new industrial style, leaving the charcoal colored sets introduced in the 1980s for a new silver styling.
Sony was not the only company producing flat screen CRTs. Other companies had already introduced high-end brands with flat-screen tubes, like Panasonic's Tau. Many other companies entered the market quickly, widely copying the new silver styling as well. The FD Trinitron was unable to regain the cachet that the Trinitron brand had previously possessed; in the 2004 Christmas season they increased sales by 5%, but only at the cost of a 75% plunge in profits after being forced to lower costs to compete in the market.
At the same time, the introduction of plasma televisions, and then LCD-based ones, led to the high-end market being increasingly focused on the "thin" sets. A series of new experimental systems followed, including the Plasmatron and experiments with Organic light-emitting diode
s and other technologies, but Sony's attempts to introduce a best-of-breed system all failed.
Sony eventually "threw in the towel" on (stopped producing the) Triniton, ending production in Japan some time in 2004. In 2007, Sony announced that it would no longer market or sell Trinitrons in the USA or Canada, but continue to sell the Trinitron in China, India, and regions of South America using tubes delivered from their Singapore
plant. Production in Singapore finally ended in March 2008, only months after ending production of their rear-projection systems. Two lines of the factory were later brought back online to supply the professional market.
Today, Sony produces only LCD televisions in their BRAVIA line, based on screens initially from Samsung
and later Sharp
. Sony currently only sells their WEGA FD Trinitron televisions in developing nations like China.
.
The single gun consists of a long-necked tube with a single electrode at its base, flaring out into a horizontally-aligned rectangular shape with three vertically-aligned rectangular cathodes inside. Each cathode is fed the amplified signal from one of the decoded RGB signals.
The electrons from the cathodes are all aimed toward a single point at the back of the screen where they hit the aperture grille, a steel sheet with vertical slots cut in it. Due to the slight separation of the cathodes at the back of the tube, the three beams approach the grille at slightly different angles. When they pass through the grille they retain this angle, hitting their individual colored phosphors that are deposited in vertical stripes on the inside of the faceplate. The main purpose of the grille is to ensure that each beam strikes only the phosphor stripes for its color, much as does a shadow mask. However, unlike a shadow mask, there are essentially no obstructions along each entire phosphor stripe. (Larger CRTs have a few horizontal stabilizing wires part way between top and bottom, but in practice, they are not noticed.)
Another advantage of the aperture grille was that the distance between the wires remained constant vertically across the screen. In the shadow mask design the size of the holes in the mask is defined by the required resolution of the phosphor dots on the screen, which was constant. However, the distance from the guns to the holes changed; for dots near the center of the screen the distance was its shortest, at points in the corners it was at its maximum. To ensure that the guns were focused on the holes, a system known as dynamic convergence had to constantly adjust the focus point as the beam moved across the screen. In the Trinitron design the problem was greatly simplified, requiring changes only for large screen sizes, and only on a line-by-line basis.
For this reason, Trinitron systems are easier to focus than shadow masks, and generally had a sharper image. This was a major selling point of the Trinitron design for much of its history. In the 1990s new computer controlled real-time feedback focusing systems eliminated this advantage, as well as leading to the introduction of "true flat" designs.
sets due to larger scan lines of the video being displayed. On computer monitors, where the lines are much closer together, the wires are often visible. This is a minor drawback of the Trinitron standard which is not shared by shadow mask CRTs.
Sony
, commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....
's brand name for its line of aperture grille
Aperture grille
An aperture grille is one of two major technologies used to manufacture color cathode ray tube televisions and computer displays; the other is shadow mask....
based CRTs
Cathode ray tube
The cathode ray tube is a vacuum tube containing an electron gun and a fluorescent screen used to view images. It has a means to accelerate and deflect the electron beam onto the fluorescent screen to create the images. The image may represent electrical waveforms , pictures , radar targets and...
used in television set
Television set
A television set is a device that combines a tuner, display, and speakers for the purpose of viewing television. Television sets became a popular consumer product after the Second World War, using vacuum tubes and cathode ray tube displays...
s and computer display
Computer display
A monitor or display is an electronic visual display for computers. The monitor comprises the display device, circuitry, and an enclosure...
monitors. One of the first truly new television systems to enter the market since the 1950s, the Trinitron was announced in 1966 to wide acclaim for its bright images, about 25% brighter than common shadow mask
Shadow mask
The shadow mask is one of two major technologies used to manufacture cathode ray tube televisions and computer displays that produce color images. The other approach is aperture grille, better known by its trade name, Trinitron. All early color televisions and the majority of CRT computer monitors...
televisions of the same era. Constant improvement in the basic technology and attention to overall quality allowed Sony to charge a premium for Trinitron devices into the 1990s.
Patent protection on the basic Trinitron design ran out in 1996, and it quickly faced a number of competitors at much lower prices. Sony responded by introducing their flat-screen FD Trinitron designs (WEGA), which maintained their premier position in the market into the early 2000s. However, these designs were surpassed relatively quickly by plasma and LCD designs. Sony removed the last Trinitron televisions from their product catalogs in 2006, and ceased production in early 2008. Video monitors are the only remaining Trinitron products being produced by Sony, at a low production rate, although the basic technology can still be found in downmarket televisions from 3rd parties.
The name Trinitron was derived from trinity
Trinity (disambiguation)
- Religion :* Trinity, the Christian concept of God as three persons.* Trimurti, a concept in Hinduism* Ayyavazhi Trinity, the incarnation of God in Ayyavazhi theology* Trinity Church - Film :* Trinity , a 2001 science fiction film...
, meaning the union of three, and tron from electron tube, after the way that the Trinitron combined the three separate electron guns of other CRT designs into one.
Color television
Color television had been studied even before commercial broadcasting became common, but it was only in the late 1940s that the problem was seriously considered. At the time, a number of systems were being proposed that used separate red, green and blue signals (RGB), broadcast in succession. Most systems broadcast entire frames in sequence, with a colored filter (or "gelColor gel
A color gel or color filter , also known as lighting gel or simply gel, is a transparent colored material that is used in theatre, event production, photography, videography and cinematography to color light and for color correction...
") that rotated in front of an otherwise conventional black and white television tube. Because they broadcast separate signals for the different colors, all of these systems were incompatible with existing black and white sets. Another problem was that the mechanical filter made them flicker unless very high refresh rates were used. In spite of these problems, the United States Federal Communication Commission selected a sequential-frame 144 frame/s standard from CBS
CBS
CBS Broadcasting Inc. is a major US commercial broadcasting television network, which started as a radio network. The name is derived from the initials of the network's former name, Columbia Broadcasting System. The network is sometimes referred to as the "Eye Network" in reference to the shape of...
as their color broadcast in 1950.
RCA
RCA
RCA Corporation, founded as the Radio Corporation of America, was an American electronics company in existence from 1919 to 1986. The RCA trademark is currently owned by the French conglomerate Technicolor SA through RCA Trademark Management S.A., a company owned by Technicolor...
worked along different lines entirely, using the luminance-chrominance system. This system did not directly encode or transmit the RGB signals; instead it combined these colors into one overall brightness figure, the "luminance
Luminance
Luminance is a photometric measure of the luminous intensity per unit area of light travelling in a given direction. It describes the amount of light that passes through or is emitted from a particular area, and falls within a given solid angle. The SI unit for luminance is candela per square...
". Luminance closely matched the black and white signal of existing broadcasts, allowing it to be displayed on existing televisions. This was a major advantage over the mechanical systems being proposed by other groups. Color information was then separately encoded and folded into the signal as a high-frequency modification to produce a composite video
Composite video
Composite video is the format of an analog television signal before it is combined with a sound signal and modulated onto an RF carrier. In contrast to component video it contains all required video information, including colors in a single line-level signal...
signal – on a black and white television this extra information would be seen as a slight randomization of the image intensity, but the limited resolution of existing sets made this invisible in practice. On color sets the signal would be extracted, decoded back into RGB, and displayed.
Although RCA's system had enormous benefits, it had not been successfully developed because it was difficult to produce the display tubes. Black and white TVs used a continuous signal and the tube could be coated with an even deposit of phosphor. With Valensi's system, the color was changing continually along the line, which was far too fast for any sort of mechanical filter to follow. Instead, the phosphor had to be broken down into a discrete pattern of colored spots. Focusing the right signal on each of these tiny spots was beyond the capability of electron gun
Electron gun
An electron gun is an electrical component that produces an electron beam that has a precise kinetic energy and is most often used in television sets and computer displays which use cathode ray tube technology, as well as in other instruments, such as electron microscopes and particle...
s of the era, and RCA's early experiments used three-tube projectors, or mirror-based systems known as "Triniscope
Triniscope
The Triniscope was an early color television system developed by RCA. It used three separate video tubes with colored phosphors producing the primary colors, combining the images through dichroic mirrors onto a screen for viewing....
".
Shadow masks
RCA eventually solved the problem of displaying the color images with their introduction of the shadow maskShadow mask
The shadow mask is one of two major technologies used to manufacture cathode ray tube televisions and computer displays that produce color images. The other approach is aperture grille, better known by its trade name, Trinitron. All early color televisions and the majority of CRT computer monitors...
. The shadow mask consists of a thin sheet of steel with tiny holes photo etched
Photolithography
Photolithography is a process used in microfabrication to selectively remove parts of a thin film or the bulk of a substrate. It uses light to transfer a geometric pattern from a photomask to a light-sensitive chemical "photoresist", or simply "resist," on the substrate...
into it, placed just behind the front surface of the picture tube. Three guns, arranged in a triangle, were all aimed at the holes. Stray electrons at the edge of the beam were cut off by the mask, creating a sharply focused spot that was small enough to hit a single colored phosphor on the screen. Since each of the guns was aimed at the hole from a slightly different angle, the spots of phosphor on the tube could be separated slightly to prevent overlap.
The disadvantage of this approach was that for any given amount of gun power, the shadow mask filtered out the majority of the energy. To ensure there was no overlap of the beam on the screen, the dots had to be separated and covered perhaps 25% of its surface. This led to very dim images, requiring much greater electron beam power in order to provide a useful picture. Moreover, the system was highly dependent on the relative angles of the beams between the three guns, which required constant adjustment by the user to ensure the guns hit the correct colors. In spite of this, the technical superiority of the RCA system was overwhelming compared to the CBS system, and was selected as the new NTSC standard in 1953. The first broadcast using the new standard occurred on New Year's Day in 1954, when NBC broadcast the Tournament of Roses Parade
Tournament of Roses Parade
The Tournament of Roses Parade, better known as the Rose Parade, is "America's New Year Celebration", a festival of flower-covered floats, marching bands, equestrians and a college football game on New Year's Day , produced by the non-profit Pasadena Tournament of Roses Association.The annual...
.
In spite of this early start, only a few years after regularly scheduled television broadcasting had begun, consumer uptake of color televisions was very slow to start. The dim images, constant adjustments and high costs had kept them in a niche of their own. Low consumer acceptance led to a lack of color programming, further reducing the demand for the sets in a chicken or the egg situation. In the United States in 1960, only 1 color set was sold for every 50 sets sold in total.
Chromatron
Sony had entered the television market in 1960 with the black and white TV8-301, the first transistorized television and the first portable design. A combination of factors, including its small screen size, limited its sales to niche markets. Sony engineers had been studying the color market, but the situation in Japan was even worse than the U.S.; they accounted for only 300 of the 9 million sets sold that year. But by 1961 dealers were asking the Sony sales department when a color set would be available, and the sales department put pressure on engineering in turn. Masaru IbukaMasaru Ibuka
Masaru Ibuka was a Japanese electronics industrialist. He co-founded what is now Sony....
, Sony's president and co-founder, steadfastly refused to develop a system based on RCA's shadow mask design, which he considered technically deficient. He insisted on developing a unique solution.
In 1961 a Sony delegation was visiting the IEEE trade show in New York City
New York City
New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...
, including Ibuka, Akio Morita
Akio Morita
Akio Morita KBE was a Japanese businessman and co-founder of Sony Corporation along with Masaru Ibuka.-Early life:...
(Sony's other co-founder) and Nobutoshi Kihara
Nobutoshi Kihara
Nobutoshi Kihara was an engineer at Sony, best known for his work on the original Walkman cassette-tape player in the 1970s and was commonly called Mr...
, who was promoting his new CV-2000
CV-2000
CV-2000 was one of the world's first home video tape recorders , introduced by Sony in August, 1965. The 'CV' in the model name stood for 'Consumer Video' and was also known as Portapak. This was Sony's domestic format throughout the 1960s....
home video tape recorder
Video tape recorder
A video tape recorder is a tape recorder that can record video material, usually on a magnetic tape. VTRs originated as individual tape reels, serving as a replacement for motion picture film stock and making recording for television applications cheaper and quicker. An improved form included the...
. This was Kihara's first trip abroad and he spent much of his time wandering the trade floor, where he came across a small booth by the small company Autometric
Autometric
Autometric Inc. was a company spun out of Paramount Pictures to work with early satellite imagery. The company created image analysis products for representing imagery on the earth, cataloging, and image augmentation. This company was purchase by Boeing Inc. at the end of 2000...
. They were demonstrating a new type of color television based on the Chromatron
Chromatron
The Chromatron is a color television cathode ray tube design invented by Nobel prize-winner Ernest Lawrence and developed commercially by Sony, Litton Industries and others. The Chromatron offered brighter images than conventional color television systems using a shadow mask, but a host of...
system, which used a single electron gun and a mask of thin wires instead of a shadow mask. The resulting image was far brighter than anything the RCA design could produce, and lacked the convergence problems that required constant adjustments. He quickly brought Morita and Ibuka to see the design, and Morita was "sold" on the spot.
Morita arranged a deal with Paramount Pictures
Paramount Pictures
Paramount Pictures Corporation is an American film production and distribution company, located at 5555 Melrose Avenue in Hollywood. Founded in 1912 and currently owned by media conglomerate Viacom, it is America's oldest existing film studio; it is also the last major film studio still...
, who was paying for Chromatic Labs' development of the Chromatron, taking over the entire project. In early 1963 Senri Miyaoka was sent to Manhattan to arrange the transfer of the technology to Sony, which would lead to the closing of Chromatic Labs. He was unimpressed with the labs, describing the windowless basement as "squalor". The American team was only too happy to point out the serious flaws in the Chromatron system, telling Miyaoka that the design was hopeless. By September 1964, a 17 inch prototype had been built in Japan, but mass-production test runs were demonstrating serious problems. Sony engineers were unable to make a version of Chromatron that could be reliably mass produced.
When sets were finally made available in late 1964, they were put on the market at a competitive 198,000 yen ($550), but cost the company over 400,000 yen to produce. Ibuka had bet the company on Chromatron and had already set up a new factory to produce them with the hopes that the production problems would be ironed out and the line would become profitable. After several thousand sets had shipped the situation was no better, while Panasonic
Panasonic
Panasonic is an international brand name for Japanese electric products manufacturer Panasonic Corporation, which was formerly known as Matsushita Electric Industrial Co., Ltd...
and Toshiba
Toshiba
is a multinational electronics and electrical equipment corporation headquartered in Tokyo, Japan. It is a diversified manufacturer and marketer of electrical products, spanning information & communications equipment and systems, Internet-based solutions and services, electronic components and...
were in the process of introducing sets based on RCA licenses. By 1966 the Chromatron was breaking the company financially.
Trinitron
In the autumn of 1966 Ibuka finally gave in, and announced he would personally lead a search for a replacement for Chromatron. Susumu Yoshida was sent to the U.S. to look for potential licenses, and was impressed with the improvements that RCA had made in overall brightness by introducing new rare earth phosphorsPhosphor
A phosphor, most generally, is a substance that exhibits the phenomenon of luminescence. Somewhat confusingly, this includes both phosphorescent materials, which show a slow decay in brightness , and fluorescent materials, where the emission decay takes place over tens of nanoseconds...
on the screen. He also saw General Electric
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...
's "Porta-color" design, using three guns in a row instead of a triangle, which allowed a greater portion of the screen to be lit. His report was cause for concern in Japan, where it seemed Sony was falling ever-farther behind the U.S. designs. They might be forced to license the shadow mask system if they wanted to remain competitive.
Ibuka was not willing to give up entirely, and had his 30 engineers explore a wide variety of approaches to see if they could come up with their own design. At one point Yoshida asked Senri Miyaoka if the in-line gun arrangement used by GE could be replaced by a single gun with three cathode
Cathode
A cathode is an electrode through which electric current flows out of a polarized electrical device. Mnemonic: CCD .Cathode polarity is not always negative...
s; this would be more difficult to build, but be lower cost in the long run. Miyaoka built a prototype and was astonished how well it worked, although it had focussing problems. Later that week, on Saturday, Miyaoka was summoned to Ibuka's office while he was attempting to leave work to attend his weekly cello practice. Yoshida had just informed Ibuka about his success, and the two asked Miyaoka if they could really develop the gun into a workable product. Miyaoka, anxious to leave, answered yes, excused himself, and left. That Monday Ibuka announced that Sony would be developing a new color television design, based on Miyaoka's prototype. By February 1967 the focusing problems had been solved, and because there was a single gun, the focusing was achieved with permanent magnets instead of a coil, and required no after manufacturing manual adjustments.
During development, Sony engineer Akio Ohgoshi introduced another modification. GE's system improved on the RCA shadow mask by replacing the small round holes with slightly larger rectangles. Since the guns were in-line, their electrons would land onto three rectangular patches instead of three smaller spots, about doubling the lit area. Ohgoshi proposed removing the mask entirely and replacing it with a series of vertical slots instead, lighting the entire screen. Although this would require the guns to be very carefully aligned with the phosphors on the tube in order to ensure they hit the right colors; with Miyaoka's new tube this appeared possible. In practice this proved easy to build but difficult to place in the tube – the fine wires were mechanically weak and tended to move when the tubes were bumped, resulting in shifting colors on the screen. This problem was solved by running fine tungsten wires across the grille horizontally to keep them in place.
The combination of three-in-one electron gun and the replacement of the shadow mask with the aperture grille
Aperture grille
An aperture grille is one of two major technologies used to manufacture color cathode ray tube televisions and computer displays; the other is shadow mask....
resulted in a unique and easily patentable product. Officially introduced by Ikuba in April 1968, the original 12 inch Trinitron had a display quality that easily surpassed any commercial set in terms of brightness, color fidelity, and simplicity of operation. The tube was also nearly flat vertically, a side-effect of the vertical wires in the aperture grille, which gave it a unique and appealing look. It was also all solid state
Solid state (electronics)
Solid-state electronics are those circuits or devices built entirely from solid materials and in which the electrons, or other charge carriers, are confined entirely within the solid material...
, with the exception of the picture tube itself, which allowed it to be much more compact and cool running than designs like GE's Porta-color. (At least some Trinitron faceplates were actually toroidal segments, with a vertical-plane radius of curvature much larger than that for the horizontal plane. Observing bright reflections on the surface confirms this.)
Ikuba ended the press conference by claiming that 10,000 sets would be available by October, well beyond what engineering had told him was possible. Ikuba cajoled Yoshida to take over the effort of bringing the sets into production, and although Yoshida was furious at being put in charge of a task he felt was impossible, he finally accepted the assignment and successfully met the production goal. The KV-1210 was introduced in limited numbers in Japan in October as promised, and in the U.S. as the KV-1210U the following year.
In spite of Trinitron and Chromatron having no technology in common, the shared single electron gun has led to many erroneous claims that the two are similar, or the same.
Despite the statement above claiming that there were no valves inside Trinitron TV sets, for a brief period in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
between 1969 and 1971/72, the KV-1320UB was fitted with 3AT2 valves for the extra high tension
Extra high tension
The definition of extra high tension or extra high voltage depends on the context of the discussion.In electric power transmission engineering this refers to equipment designed for more than 235,000 volts between conductors....
(high voltage). Later on, the KV-1320UB was redesigned internally and externally to become all solid-state. Despite containing vacuum tubes, the first version of the KV-1320UB was promoted as being all solid-state. The later version of this model is identified as having no wooden outer-shell. These early color sets intended for the UK market had a PAL decoder that was different from those invented and licensed by Telefunken
Telefunken
Telefunken is a German radio and television apparatus company, founded in Berlin in 1903, as a joint venture of Siemens & Halske and the Allgemeine Elektricitäts-Gesellschaft...
of Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
, who invented this color system. The decoder inside the UK-sold Sony color Trinitron sets, from the KV-1300UB to the KV-1330UB had an NTSC
NTSC
NTSC, named for the National Television System Committee, is the analog television system that is used in most of North America, most of South America , Burma, South Korea, Taiwan, Japan, the Philippines, and some Pacific island nations and territories .Most countries using the NTSC standard, as...
decoder adapted for PAL
PAL
PAL, short for Phase Alternating Line, is an analogue television colour encoding system used in broadcast television systems in many countries. Other common analogue television systems are NTSC and SECAM. This page primarily discusses the PAL colour encoding system...
. The decoder used a 64 microsecond delay line to store every other line, but instead of using the delay line to average out the phase of the current line and the "remembered" line (as with "Deluxe PAL"), it simply repeats the same line twice. Any phase errors can then be compensated for by using a Tint control on the front of the set.
Reception
Reviews of the Trinitron were universally positive, although they all mentioned its high cost. Sony won an Emmy AwardEmmy Award
An Emmy Award, often referred to simply as the Emmy, is a television production award, similar in nature to the Peabody Awards but more focused on entertainment, and is considered the television equivalent to the Academy Awards and the Grammy Awards .A majority of Emmys are presented in various...
for the Trinitron in 1973. On his 84th birthday in 1992, Ibuka claimed the Trinitron was his proudest product.
New models quickly followed. Larger sizes at 19" and then 27" were introduced, as well as smaller including a 7" portable. In the mid-1980s a new phosphor coating was introduced that was much darker than earlier sets, giving the screens a black color when turned off, as opposed to the earlier light grey. Early models were generally packaged in silver cases, but with the introduction of the darker screens Sony also introduced new all-black cases, following a similar change in color taking place in the hi-fi world. This line expanded with 32", 35" and finally 40" units in the 1990s.
In 1980 Sony introduced the "ProFeel" line of prosumer component televisions, consisting of a range of Trinitron monitors that could be connected to standardized tuners. The original lineup consisted of the KX-20xx1 20" and KX-27xx1 27" monitors (the "xx" is an identifier, PS for Europe, HF for Japan, etc.) the VTX-100ES tuner and TXT-100G TeleText decoder. They were often used with a set of SS-X1A stereo speakers, which matched the grey boxy styling of the suite. The concept was to build a market similar to contemporary stereo equipment, where components from different vendors could be mixed to produce a complete system. However, a lack of any major 3rd party components, along with custom connectors between the tuner and monitors, meant that the systems were never really mixable. They were popular high-end units, however, and found a strong following in production companies where the excellent quality picture made them effective low-cost monitors. A second series of all-black units followed in 1986, the ProFeel Pro, sporting a space-frame around the back of the trapezoidal enclosure that doubled as a carrying handle and holder for the pop-out speakers. These units were paired with the VT-X5R tuner and optionally the APM-X5A speakers.
Sony also produced lines of Trinitron professional studio monitors, the PVM (Pro Video Monitor) and BVM (Broadcast Video Monitor) lines. These models were packaged in grey metal cubes with a variety of inputs that accepted practically any analog format. They originally used tubes similar to the ProFeel line, but over time they gradually increased in resolution until the late 1990s when they offered over 900 lines. When these were cancelled as part of the wider Trinitron shutdown in 2007, professionals forced Sony to re-open two of the lines to produce the 20 and 14 inch models.
Among similar products, Sony produced the KV-1311 monitor/TV combination. It accepted NTSC-compatible video from Amiga
computers as well as analog broadcast TV. Along with its other functions, it had video and audio inputs and outputs as well as a wideband sound-IF decoded output. Its exterior looks much like the monitor illustrated here, with added TV controls.
By this time, Sony was well established as a supplier of reliable equipment; it was preferable to have minimal field failures instead of supporting an extensive service network for the entire USA.
Sony started developing the Trinitron for computer monitor use in the late 1970s. Demand was high, so high that there were examples of 3rd party companies removing Trinitron tubes from televisions to use as monitors. In response, Sony started development of the GDM (Graphic Display Monitor) in 1983, which offered high resolution and faster refresh rates. Sony aggressively promoted the GDM and it became a standard on high-end monitors by the late 1980s. Particularly common models include the Apple Inc. 13" model that was originally sold with the Macintosh II
Macintosh II
The Apple Macintosh II was the first personal computer model of the Macintosh II series in the Apple Macintosh line and the first Macintosh to support a color display.- History :...
starting in 1987. Other well known users included Digital Equipment Corporation
Digital Equipment Corporation
Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...
, IBM
IBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
, Silicon Graphics
Silicon Graphics
Silicon Graphics, Inc. was a manufacturer of high-performance computing solutions, including computer hardware and software, founded in 1981 by Jim Clark...
, Sun Microsystems
Sun Microsystems
Sun Microsystems, Inc. was a company that sold :computers, computer components, :computer software, and :information technology services. Sun was founded on February 24, 1982...
and others. Demand for a lower cost solution led to the CDP series. In May 1988 they introduced the high-end 20 inch DDM model (Data Display Monitor) with a maximum resolution of 2,048 by 2,048, which went on to be used in the FAA's Advanced Automation System air traffic control
Air traffic control
Air traffic control is a service provided by ground-based controllers who direct aircraft on the ground and in the air. The primary purpose of ATC systems worldwide is to separate aircraft to prevent collisions, to organize and expedite the flow of traffic, and to provide information and other...
system.
These developments meant that Sony was well placed to introduce high-definition televisions (HDTV). In April 1981 they announced the High Definition Video System
Sony HDVS
Sony HDVS was a range of high-definition video equipment developed in the 1980s to support an early analog high-definition television system thought to be the broadcast television systems that would be in use today...
(HDVS), a suite of MUSE
Multiple sub-nyquist sampling Encoding system
MUSE , was a dot-interlaced digital video compression system that used analog modulation for transmission to deliver 1125-line high definition video signals to the home. Japan had the earliest working HDTV system, which was named Hi-Vision with design efforts going back to 1979...
equipment including cameras, recorders, Trinitron monitors and projection TVs.
Sony shipped its 100 millionth Trinitron screen in July 1994, 25 years after it had been introduced. New uses in the computer field and the demand for higher resolution televisions to match the quality of DVD
DVD
A DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....
when it was introduced in 1996 led to increased sales, delivering another 180 million units in the next decade.
End of Trinitron
Mitsubishi Electric
is a multinational electronics and information technology company headquartered in Tokyo, Japan. It is one of the core companies of the Mitsubishi Group....
(whose monitor production is now part of NEC Display Solutions) were free to use the Trinitron design for their own product line without license from Sony although they could not use the Trinitron name. For example, Mitsubishi's are called Diamondtron. To some degree the name Trinitron became a generic term referring to any similar set. At least some Diamondtron CRT faceplates are spherical sectors; reflections of such objects as ceiling light fixtures are reduced in size and do not change shape regardless of where they appear.
Sony responded with the FD Trinitron, which used computer controlled feedback systems to ensure sharp focus across a flat screen. Initially introduced on their 27, 32 and 36 inch models in 1998, the new tubes were offered in a variety of resolutions for different uses. The basic WEGA models supported normal 480i signals, but a larger version offered 16:9 aspect ratio
Aspect ratio
The aspect ratio of a shape is the ratio of its longer dimension to its shorter dimension. It may be applied to two characteristic dimensions of a three-dimensional shape, such as the ratio of the longest and shortest axis, or for symmetrical objects that are described by just two measurements,...
s. The technology was quickly applied to the entire Trinitron range, from 13 to 36 inch. High resolution versions, Hi-Scan and Super Fine Pitch, were also produced. With the introduction of the FD Trinitron, Sony also introduced a new industrial style, leaving the charcoal colored sets introduced in the 1980s for a new silver styling.
Sony was not the only company producing flat screen CRTs. Other companies had already introduced high-end brands with flat-screen tubes, like Panasonic's Tau. Many other companies entered the market quickly, widely copying the new silver styling as well. The FD Trinitron was unable to regain the cachet that the Trinitron brand had previously possessed; in the 2004 Christmas season they increased sales by 5%, but only at the cost of a 75% plunge in profits after being forced to lower costs to compete in the market.
At the same time, the introduction of plasma televisions, and then LCD-based ones, led to the high-end market being increasingly focused on the "thin" sets. A series of new experimental systems followed, including the Plasmatron and experiments with Organic light-emitting diode
Organic light-emitting diode
An OLED is a light-emitting diode in which the emissive electroluminescent layer is a film of organic compounds which emit light in response to an electric current. This layer of organic semiconductor material is situated between two electrodes...
s and other technologies, but Sony's attempts to introduce a best-of-breed system all failed.
Sony eventually "threw in the towel" on (stopped producing the) Triniton, ending production in Japan some time in 2004. In 2007, Sony announced that it would no longer market or sell Trinitrons in the USA or Canada, but continue to sell the Trinitron in China, India, and regions of South America using tubes delivered from their Singapore
Singapore
Singapore , officially the Republic of Singapore, is a Southeast Asian city-state off the southern tip of the Malay Peninsula, north of the equator. An island country made up of 63 islands, it is separated from Malaysia by the Straits of Johor to its north and from Indonesia's Riau Islands by the...
plant. Production in Singapore finally ended in March 2008, only months after ending production of their rear-projection systems. Two lines of the factory were later brought back online to supply the professional market.
Today, Sony produces only LCD televisions in their BRAVIA line, based on screens initially from Samsung
Samsung
The Samsung Group is a South Korean multinational conglomerate corporation headquartered in Samsung Town, Seoul, South Korea...
and later Sharp
Sharp Corporation
is a Japanese multinational corporation that designs and manufactures electronic products. Headquartered in Abeno-ku, Osaka, Japan, Sharp employs more than 55,580 people worldwide as of June 2011. The company was founded in September 1912 and takes its name from one of its founder's first...
. Sony currently only sells their WEGA FD Trinitron televisions in developing nations like China.
Basic concept
The Trinitron design incorporates two unique features: the single-gun three-cathode picture tube, and the vertically aligned aperture grilleAperture grille
An aperture grille is one of two major technologies used to manufacture color cathode ray tube televisions and computer displays; the other is shadow mask....
.
The single gun consists of a long-necked tube with a single electrode at its base, flaring out into a horizontally-aligned rectangular shape with three vertically-aligned rectangular cathodes inside. Each cathode is fed the amplified signal from one of the decoded RGB signals.
The electrons from the cathodes are all aimed toward a single point at the back of the screen where they hit the aperture grille, a steel sheet with vertical slots cut in it. Due to the slight separation of the cathodes at the back of the tube, the three beams approach the grille at slightly different angles. When they pass through the grille they retain this angle, hitting their individual colored phosphors that are deposited in vertical stripes on the inside of the faceplate. The main purpose of the grille is to ensure that each beam strikes only the phosphor stripes for its color, much as does a shadow mask. However, unlike a shadow mask, there are essentially no obstructions along each entire phosphor stripe. (Larger CRTs have a few horizontal stabilizing wires part way between top and bottom, but in practice, they are not noticed.)
Advantages
In comparison to early shadow mask designs, the Trinitron grille cuts off much less of the signal coming from the electron guns. RCA sets built in the 1950s cut off about 85% of the incoming signal, while the grille cuts off about 25%. Improvements to the shadow mask designs continually narrowed this difference in the two designs, and by the late 1980s the difference in performance, at least theoretically, was eliminated.Another advantage of the aperture grille was that the distance between the wires remained constant vertically across the screen. In the shadow mask design the size of the holes in the mask is defined by the required resolution of the phosphor dots on the screen, which was constant. However, the distance from the guns to the holes changed; for dots near the center of the screen the distance was its shortest, at points in the corners it was at its maximum. To ensure that the guns were focused on the holes, a system known as dynamic convergence had to constantly adjust the focus point as the beam moved across the screen. In the Trinitron design the problem was greatly simplified, requiring changes only for large screen sizes, and only on a line-by-line basis.
For this reason, Trinitron systems are easier to focus than shadow masks, and generally had a sharper image. This was a major selling point of the Trinitron design for much of its history. In the 1990s new computer controlled real-time feedback focusing systems eliminated this advantage, as well as leading to the introduction of "true flat" designs.
Visible Support Wires
Even small changes in the alignment of the grille over the phosphors can cause the coloring to shift. Since the wires are thin, small bumps can cause the wires to shift alignment if they are not held in place. Monitors using this technology have one or more thin tungsten wires running horizontally across the grille to prevent this. Screens 15" and below have one wire located about two thirds of the way down the screen, while monitors greater than 15" have 2 wires at the one-third and two-thirds positions. These wires are less apparent or completely obscured on standard definitionStandard-definition television
Sorete-definition television is a television system that uses a resolution that is not considered to be either enhanced-definition television or high-definition television . The term is usually used in reference to digital television, in particular when broadcasting at the same resolution as...
sets due to larger scan lines of the video being displayed. On computer monitors, where the lines are much closer together, the wires are often visible. This is a minor drawback of the Trinitron standard which is not shared by shadow mask CRTs.
Anti Glare Coating
This is a polyurethane sheet coated to scatter reflections and can be very easily damaged. The fix is to simply remove the sheet entirely, which one can do on Trinitron and Diamondtron CRT Monitors using a stanley blade and a chopstick.Partial list of other aperture grille brands
- NEC/Mitsubishi "Diamondtron"
- ViewSonicViewSonicViewSonic Corporation is a manufacturer and provider of visual technology, specifically CRT monitors, liquid crystal displays, projectors, plasma displays, HDTV technology, and mobile products, including Mini and All-in-One PCs and wireless monitors....
"SonicTron" - MAG InnovisionMAG InnovisionMAG Innovision is a Taiwan-headquartered manufacturer and provider of visual technology, specifically CRT monitors, liquid crystal displays, projectors, plasma displays, and HDTV technology....
"Technitron" - Gateway Computer "Vivitron"
See also
- Allen B. DuMontAllen B. DuMontAllen Balcom DuMont also spelled Du Mont, was an American scientist and inventor best known for improvements to the cathode ray tube in 1931 for use in television receivers. Seven years later he manufactured and sold the first commercially practical television set to the public...
- aperture grilleAperture grilleAn aperture grille is one of two major technologies used to manufacture color cathode ray tube televisions and computer displays; the other is shadow mask....
- ChromatronChromatronThe Chromatron is a color television cathode ray tube design invented by Nobel prize-winner Ernest Lawrence and developed commercially by Sony, Litton Industries and others. The Chromatron offered brighter images than conventional color television systems using a shadow mask, but a host of...
- FD Trinitron
- Geer tubeGeer tubeThe Geer tube was an early single-tube color television cathode ray tube, developed by Willard Geer. The Geer tube used a pattern of small phosphor-covered three-sided pyramids on the inside of the CRT faceplate to mix together separate red, green and blue signals from three electron guns...
- shadow maskShadow maskThe shadow mask is one of two major technologies used to manufacture cathode ray tube televisions and computer displays that produce color images. The other approach is aperture grille, better known by its trade name, Trinitron. All early color televisions and the majority of CRT computer monitors...