diy projector lcd screen factory

Glass substrate with ITO electrodes. The shapes of these electrodes will determine the shapes that will appear when the LCD is switched ON. Vertical ridges etched on the surface are smooth.

A liquid-crystal display (LCD) is a flat-panel display or other electronically modulated optical device that uses the light-modulating properties of liquid crystals combined with polarizers. Liquid crystals do not emit light directlybacklight or reflector to produce images in color or monochrome.seven-segment displays, as in a digital clock, are all good examples of devices with these displays. They use the same basic technology, except that arbitrary images are made from a matrix of small pixels, while other displays have larger elements. LCDs can either be normally on (positive) or off (negative), depending on the polarizer arrangement. For example, a character positive LCD with a backlight will have black lettering on a background that is the color of the backlight, and a character negative LCD will have a black background with the letters being of the same color as the backlight. Optical filters are added to white on blue LCDs to give them their characteristic appearance.

LCDs are used in a wide range of applications, including LCD televisions, computer monitors, instrument panels, aircraft cockpit displays, and indoor and outdoor signage. Small LCD screens are common in LCD projectors and portable consumer devices such as digital cameras, watches, digital clocks, calculators, and mobile telephones, including smartphones. LCD screens are also used on consumer electronics products such as DVD players, video game devices and clocks. LCD screens have replaced heavy, bulky cathode-ray tube (CRT) displays in nearly all applications. LCD screens are available in a wider range of screen sizes than CRT and plasma displays, with LCD screens available in sizes ranging from tiny digital watches to very large television receivers. LCDs are slowly being replaced by OLEDs, which can be easily made into different shapes, and have a lower response time, wider color gamut, virtually infinite color contrast and viewing angles, lower weight for a given display size and a slimmer profile (because OLEDs use a single glass or plastic panel whereas LCDs use two glass panels; the thickness of the panels increases with size but the increase is more noticeable on LCDs) and potentially lower power consumption (as the display is only "on" where needed and there is no backlight). OLEDs, however, are more expensive for a given display size due to the very expensive electroluminescent materials or phosphors that they use. Also due to the use of phosphors, OLEDs suffer from screen burn-in and there is currently no way to recycle OLED displays, whereas LCD panels can be recycled, although the technology required to recycle LCDs is not yet widespread. Attempts to maintain the competitiveness of LCDs are quantum dot displays, marketed as SUHD, QLED or Triluminos, which are displays with blue LED backlighting and a Quantum-dot enhancement film (QDEF) that converts part of the blue light into red and green, offering similar performance to an OLED display at a lower price, but the quantum dot layer that gives these displays their characteristics can not yet be recycled.

Since LCD screens do not use phosphors, they rarely suffer image burn-in when a static image is displayed on a screen for a long time, e.g., the table frame for an airline flight schedule on an indoor sign. LCDs are, however, susceptible to image persistence.battery-powered electronic equipment more efficiently than a CRT can be. By 2008, annual sales of televisions with LCD screens exceeded sales of CRT units worldwide, and the CRT became obsolete for most purposes.

Each pixel of an LCD typically consists of a layer of molecules aligned between two transparent electrodes, often made of Indium-Tin oxide (ITO) and two polarizing filters (parallel and perpendicular polarizers), the axes of transmission of which are (in most of the cases) perpendicular to each other. Without the liquid crystal between the polarizing filters, light passing through the first filter would be blocked by the second (crossed) polarizer. Before an electric field is applied, the orientation of the liquid-crystal molecules is determined by the alignment at the surfaces of electrodes. In a twisted nematic (TN) device, the surface alignment directions at the two electrodes are perpendicular to each other, and so the molecules arrange themselves in a helical structure, or twist. This induces the rotation of the polarization of the incident light, and the device appears gray. If the applied voltage is large enough, the liquid crystal molecules in the center of the layer are almost completely untwisted and the polarization of the incident light is not rotated as it passes through the liquid crystal layer. This light will then be mainly polarized perpendicular to the second filter, and thus be blocked and the pixel will appear black. By controlling the voltage applied across the liquid crystal layer in each pixel, light can be allowed to pass through in varying amounts thus constituting different levels of gray.

The chemical formula of the liquid crystals used in LCDs may vary. Formulas may be patented.Sharp Corporation. The patent that covered that specific mixture expired.

Most color LCD systems use the same technique, with color filters used to generate red, green, and blue subpixels. The LCD color filters are made with a photolithography process on large glass sheets that are later glued with other glass sheets containing a TFT array, spacers and liquid crystal, creating several color LCDs that are then cut from one another and laminated with polarizer sheets. Red, green, blue and black photoresists (resists) are used. All resists contain a finely ground powdered pigment, with particles being just 40 nanometers across. The black resist is the first to be applied; this will create a black grid (known in the industry as a black matrix) that will separate red, green and blue subpixels from one another, increasing contrast ratios and preventing light from leaking from one subpixel onto other surrounding subpixels.Super-twisted nematic LCD, where the variable twist between tighter-spaced plates causes a varying double refraction birefringence, thus changing the hue.

LCD in a Texas Instruments calculator with top polarizer removed from device and placed on top, such that the top and bottom polarizers are perpendicular. As a result, the colors are inverted.

The optical effect of a TN device in the voltage-on state is far less dependent on variations in the device thickness than that in the voltage-off state. Because of this, TN displays with low information content and no backlighting are usually operated between crossed polarizers such that they appear bright with no voltage (the eye is much more sensitive to variations in the dark state than the bright state). As most of 2010-era LCDs are used in television sets, monitors and smartphones, they have high-resolution matrix arrays of pixels to display arbitrary images using backlighting with a dark background. When no image is displayed, different arrangements are used. For this purpose, TN LCDs are operated between parallel polarizers, whereas IPS LCDs feature crossed polarizers. In many applications IPS LCDs have replaced TN LCDs, particularly in smartphones. Both the liquid crystal material and the alignment layer material contain ionic compounds. If an electric field of one particular polarity is applied for a long period of time, this ionic material is attracted to the surfaces and degrades the device performance. This is avoided either by applying an alternating current or by reversing the polarity of the electric field as the device is addressed (the response of the liquid crystal layer is identical, regardless of the polarity of the applied field).

Displays for a small number of individual digits or fixed symbols (as in digital watches and pocket calculators) can be implemented with independent electrodes for each segment.alphanumeric or variable graphics displays are usually implemented with pixels arranged as a matrix consisting of electrically connected rows on one side of the LC layer and columns on the other side, which makes it possible to address each pixel at the intersections. The general method of matrix addressing consists of sequentially addressing one side of the matrix, for example by selecting the rows one-by-one and applying the picture information on the other side at the columns row-by-row. For details on the various matrix addressing schemes see passive-matrix and active-matrix addressed LCDs.

LCDs, along with OLED displays, are manufactured in cleanrooms borrowing techniques from semiconductor manufacturing and using large sheets of glass whose size has increased over time. Several displays are manufactured at the same time, and then cut from the sheet of glass, also known as the mother glass or LCD glass substrate. The increase in size allows more displays or larger displays to be made, just like with increasing wafer sizes in semiconductor manufacturing. The glass sizes are as follows:

Until Gen 8, manufacturers would not agree on a single mother glass size and as a result, different manufacturers would use slightly different glass sizes for the same generation. Some manufacturers have adopted Gen 8.6 mother glass sheets which are only slightly larger than Gen 8.5, allowing for more 50 and 58 inch LCDs to be made per mother glass, specially 58 inch LCDs, in which case 6 can be produced on a Gen 8.6 mother glass vs only 3 on a Gen 8.5 mother glass, significantly reducing waste.AGC Inc., Corning Inc., and Nippon Electric Glass.

In 1922, Georges Friedel described the structure and properties of liquid crystals and classified them in three types (nematics, smectics and cholesterics). In 1927, Vsevolod Frederiks devised the electrically switched light valve, called the Fréedericksz transition, the essential effect of all LCD technology. In 1936, the Marconi Wireless Telegraph company patented the first practical application of the technology, "The Liquid Crystal Light Valve". In 1962, the first major English language publication Molecular Structure and Properties of Liquid Crystals was published by Dr. George W. Gray.RCA found that liquid crystals had some interesting electro-optic characteristics and he realized an electro-optical effect by generating stripe-patterns in a thin layer of liquid crystal material by the application of a voltage. This effect is based on an electro-hydrodynamic instability forming what are now called "Williams domains" inside the liquid crystal.

In the late 1960s, pioneering work on liquid crystals was undertaken by the UK"s Royal Radar Establishment at Malvern, England. The team at RRE supported ongoing work by George William Gray and his team at the University of Hull who ultimately discovered the cyanobiphenyl liquid crystals, which had correct stability and temperature properties for application in LCDs.

The idea of a TFT-based liquid-crystal display (LCD) was conceived by Bernard Lechner of RCA Laboratories in 1968.dynamic scattering mode (DSM) LCD that used standard discrete MOSFETs.

On December 4, 1970, the twisted nematic field effect (TN) in liquid crystals was filed for patent by Hoffmann-LaRoche in Switzerland, (Swiss patent No. 532 261) with Wolfgang Helfrich and Martin Schadt (then working for the Central Research Laboratories) listed as inventors.Brown, Boveri & Cie, its joint venture partner at that time, which produced TN displays for wristwatches and other applications during the 1970s for the international markets including the Japanese electronics industry, which soon produced the first digital quartz wristwatches with TN-LCDs and numerous other products. James Fergason, while working with Sardari Arora and Alfred Saupe at Kent State University Liquid Crystal Institute, filed an identical patent in the United States on April 22, 1971.ILIXCO (now LXD Incorporated), produced LCDs based on the TN-effect, which soon superseded the poor-quality DSM types due to improvements of lower operating voltages and lower power consumption. Tetsuro Hama and Izuhiko Nishimura of Seiko received a US patent dated February 1971, for an electronic wristwatch incorporating a TN-LCD.

In 1972, the concept of the active-matrix thin-film transistor (TFT) liquid-crystal display panel was prototyped in the United States by T. Peter Brody"s team at Westinghouse, in Pittsburgh, Pennsylvania.Westinghouse Research Laboratories demonstrated the first thin-film-transistor liquid-crystal display (TFT LCD).high-resolution and high-quality electronic visual display devices use TFT-based active matrix displays.active-matrix liquid-crystal display (AM LCD) in 1974, and then Brody coined the term "active matrix" in 1975.

In 1972 North American Rockwell Microelectronics Corp introduced the use of DSM LCDs for calculators for marketing by Lloyds Electronics Inc, though these required an internal light source for illumination.Sharp Corporation followed with DSM LCDs for pocket-sized calculators in 1973Seiko and its first 6-digit TN-LCD quartz wristwatch, and Casio"s "Casiotron". Color LCDs based on Guest-Host interaction were invented by a team at RCA in 1968.TFT LCDs similar to the prototypes developed by a Westinghouse team in 1972 were patented in 1976 by a team at Sharp consisting of Fumiaki Funada, Masataka Matsuura, and Tomio Wada,

In 1983, researchers at Brown, Boveri & Cie (BBC) Research Center, Switzerland, invented the passive matrix-addressed LCDs. H. Amstutz et al. were listed as inventors in the corresponding patent applications filed in Switzerland on July 7, 1983, and October 28, 1983. Patents were granted in Switzerland CH 665491, Europe EP 0131216,

The first color LCD televisions were developed as handheld televisions in Japan. In 1980, Hattori Seiko"s R&D group began development on color LCD pocket televisions.Seiko Epson released the first LCD television, the Epson TV Watch, a wristwatch equipped with a small active-matrix LCD television.dot matrix TN-LCD in 1983.Citizen Watch,TFT LCD.computer monitors and LCD televisions.3LCD projection technology in the 1980s, and licensed it for use in projectors in 1988.compact, full-color LCD projector.

In 1990, under different titles, inventors conceived electro optical effects as alternatives to twisted nematic field effect LCDs (TN- and STN- LCDs). One approach was to use interdigital electrodes on one glass substrate only to produce an electric field essentially parallel to the glass substrates.Germany by Guenter Baur et al. and patented in various countries.Hitachi work out various practical details of the IPS technology to interconnect the thin-film transistor array as a matrix and to avoid undesirable stray fields in between pixels.

Hitachi also improved the viewing angle dependence further by optimizing the shape of the electrodes (Super IPS). NEC and Hitachi become early manufacturers of active-matrix addressed LCDs based on the IPS technology. This is a milestone for implementing large-screen LCDs having acceptable visual performance for flat-panel computer monitors and television screens. In 1996, Samsung developed the optical patterning technique that enables multi-domain LCD. Multi-domain and In Plane Switching subsequently remain the dominant LCD designs through 2006.South Korea and Taiwan,

In 2007 the image quality of LCD televisions surpassed the image quality of cathode-ray-tube-based (CRT) TVs.LCD TVs were projected to account 50% of the 200 million TVs to be shipped globally in 2006, according to Displaybank.Toshiba announced 2560 × 1600 pixels on a 6.1-inch (155 mm) LCD panel, suitable for use in a tablet computer,transparent and flexible, but they cannot emit light without a backlight like OLED and microLED, which are other technologies that can also be made flexible and transparent.

In 2016, Panasonic developed IPS LCDs with a contrast ratio of 1,000,000:1, rivaling OLEDs. This technology was later put into mass production as dual layer, dual panel or LMCL (Light Modulating Cell Layer) LCDs. The technology uses 2 liquid crystal layers instead of one, and may be used along with a mini-LED backlight and quantum dot sheets.

Since LCDs produce no light of their own, they require external light to produce a visible image.backlight. Active-matrix LCDs are almost always backlit.Transflective LCDs combine the features of a backlit transmissive display and a reflective display.

CCFL: The LCD panel is lit either by two cold cathode fluorescent lamps placed at opposite edges of the display or an array of parallel CCFLs behind larger displays. A diffuser (made of PMMA acrylic plastic, also known as a wave or light guide/guiding plateinverter to convert whatever DC voltage the device uses (usually 5 or 12 V) to ≈1000 V needed to light a CCFL.

EL-WLED: The LCD panel is lit by a row of white LEDs placed at one or more edges of the screen. A light diffuser (light guide plate, LGP) is then used to spread the light evenly across the whole display, similarly to edge-lit CCFL LCD backlights. The diffuser is made out of either PMMA plastic or special glass, PMMA is used in most cases because it is rugged, while special glass is used when the thickness of the LCD is of primary concern, because it doesn"t expand as much when heated or exposed to moisture, which allows LCDs to be just 5mm thick. Quantum dots may be placed on top of the diffuser as a quantum dot enhancement film (QDEF, in which case they need a layer to be protected from heat and humidity) or on the color filter of the LCD, replacing the resists that are normally used.

WLED array: The LCD panel is lit by a full array of white LEDs placed behind a diffuser behind the panel. LCDs that use this implementation will usually have the ability to dim or completely turn off the LEDs in the dark areas of the image being displayed, effectively increasing the contrast ratio of the display. The precision with which this can be done will depend on the number of dimming zones of the display. The more dimming zones, the more precise the dimming, with less obvious blooming artifacts which are visible as dark grey patches surrounded by the unlit areas of the LCD. As of 2012, this design gets most of its use from upscale, larger-screen LCD televisions.

RGB-LED array: Similar to the WLED array, except the panel is lit by a full array of RGB LEDs. While displays lit with white LEDs usually have a poorer color gamut than CCFL lit displays, panels lit with RGB LEDs have very wide color gamuts. This implementation is most popular on professional graphics editing LCDs. As of 2012, LCDs in this category usually cost more than $1000. As of 2016 the cost of this category has drastically reduced and such LCD televisions obtained same price levels as the former 28" (71 cm) CRT based categories.

Monochrome LEDs: such as red, green, yellow or blue LEDs are used in the small passive monochrome LCDs typically used in clocks, watches and small appliances.

Today, most LCD screens are being designed with an LED backlight instead of the traditional CCFL backlight, while that backlight is dynamically controlled with the video information (dynamic backlight control). The combination with the dynamic backlight control, invented by Philips researchers Douglas Stanton, Martinus Stroomer and Adrianus de Vaan, simultaneously increases the dynamic range of the display system (also marketed as HDR, high dynamic range television or FLAD, full-area local area dimming).

The LCD backlight systems are made highly efficient by applying optical films such as prismatic structure (prism sheet) to gain the light into the desired viewer directions and reflective polarizing films that recycle the polarized light that was formerly absorbed by the first polarizer of the LCD (invented by Philips researchers Adrianus de Vaan and Paulus Schaareman),

Due to the LCD layer that generates the desired high resolution images at flashing video speeds using very low power electronics in combination with LED based backlight technologies, LCD technology has become the dominant display technology for products such as televisions, desktop monitors, notebooks, tablets, smartphones and mobile phones. Although competing OLED technology is pushed to the market, such OLED displays do not feature the HDR capabilities like LCDs in combination with 2D LED backlight technologies have, reason why the annual market of such LCD-based products is still growing faster (in volume) than OLED-based products while the efficiency of LCDs (and products like portable computers, mobile phones and televisions) may even be further improved by preventing the light to be absorbed in the colour filters of the LCD.

A pink elastomeric connector mating an LCD panel to circuit board traces, shown next to a centimeter-scale ruler. The conductive and insulating layers in the black stripe are very small.

A standard television receiver screen, a modern LCD panel, has over six million pixels, and they are all individually powered by a wire network embedded in the screen. The fine wires, or pathways, form a grid with vertical wires across the whole screen on one side of the screen and horizontal wires across the whole screen on the other side of the screen. To this grid each pixel has a positive connection on one side and a negative connection on the other side. So the total amount of wires needed for a 1080p display is 3 x 1920 going vertically and 1080 going horizontally for a total of 6840 wires horizontally and vertically. That"s three for red, green and blue and 1920 columns of pixels for each color for a total of 5760 wires going vertically and 1080 rows of wires going horizontally. For a panel that is 28.8 inches (73 centimeters) wide, that means a wire density of 200 wires per inch along the horizontal edge.

The LCD panel is powered by LCD drivers that are carefully matched up with the edge of the LCD panel at the factory level. The drivers may be installed using several methods, the most common of which are COG (Chip-On-Glass) and TAB (Tape-automated bonding) These same principles apply also for smartphone screens that are much smaller than TV screens.anisotropic conductive film or, for lower densities, elastomeric connectors.

Monochrome and later color passive-matrix LCDs were standard in most early laptops (although a few used plasma displaysGame Boyactive-matrix became standard on all laptops. The commercially unsuccessful Macintosh Portable (released in 1989) was one of the first to use an active-matrix display (though still monochrome). Passive-matrix LCDs are still used in the 2010s for applications less demanding than laptop computers and TVs, such as inexpensive calculators. In particular, these are used on portable devices where less information content needs to be displayed, lowest power consumption (no backlight) and low cost are desired or readability in direct sunlight is needed.

A comparison between a blank passive-matrix display (top) and a blank active-matrix display (bottom). A passive-matrix display can be identified when the blank background is more grey in appearance than the crisper active-matrix display, fog appears on all edges of the screen, and while pictures appear to be fading on the screen.

STN LCDs have to be continuously refreshed by alternating pulsed voltages of one polarity during one frame and pulses of opposite polarity during the next frame. Individual pixels are addressed by the corresponding row and column circuits. This type of display is called response times and poor contrast are typical of passive-matrix addressed LCDs with too many pixels and driven according to the "Alt & Pleshko" drive scheme. Welzen and de Vaan also invented a non RMS drive scheme enabling to drive STN displays with video rates and enabling to show smooth moving video images on an STN display.

Bistable LCDs do not require continuous refreshing. Rewriting is only required for picture information changes. In 1984 HA van Sprang and AJSM de Vaan invented an STN type display that could be operated in a bistable mode, enabling extremely high resolution images up to 4000 lines or more using only low voltages.

High-resolution color displays, such as modern LCD computer monitors and televisions, use an active-matrix structure. A matrix of thin-film transistors (TFTs) is added to the electrodes in contact with the LC layer. Each pixel has its own dedicated transistor, allowing each column line to access one pixel. When a row line is selected, all of the column lines are connected to a row of pixels and voltages corresponding to the picture information are driven onto all of the column lines. The row line is then deactivated and the next row line is selected. All of the row lines are selected in sequence during a refresh operation. Active-matrix addressed displays look brighter and sharper than passive-matrix addressed displays of the same size, and generally have quicker response times, producing much better images. Sharp produces bistable reflective LCDs with a 1-bit SRAM cell per pixel that only requires small amounts of power to maintain an image.

Segment LCDs can also have color by using Field Sequential Color (FSC LCD). This kind of displays have a high speed passive segment LCD panel with an RGB backlight. The backlight quickly changes color, making it appear white to the naked eye. The LCD panel is synchronized with the backlight. For example, to make a segment appear red, the segment is only turned ON when the backlight is red, and to make a segment appear magenta, the segment is turned ON when the backlight is blue, and it continues to be ON while the backlight becomes red, and it turns OFF when the backlight becomes green. To make a segment appear black, the segment is always turned ON. An FSC LCD divides a color image into 3 images (one Red, one Green and one Blue) and it displays them in order. Due to persistence of vision, the 3 monochromatic images appear as one color image. An FSC LCD needs an LCD panel with a refresh rate of 180 Hz, and the response time is reduced to just 5 milliseconds when compared with normal STN LCD panels which have a response time of 16 milliseconds.

Samsung introduced UFB (Ultra Fine & Bright) displays back in 2002, utilized the super-birefringent effect. It has the luminance, color gamut, and most of the contrast of a TFT-LCD, but only consumes as much power as an STN display, according to Samsung. It was being used in a variety of Samsung cellular-telephone models produced until late 2006, when Samsung stopped producing UFB displays. UFB displays were also used in certain models of LG mobile phones.

In-plane switching is an LCD technology that aligns the liquid crystals in a plane parallel to the glass substrates. In this method, the electrical field is applied through opposite electrodes on the same glass substrate, so that the liquid crystals can be reoriented (switched) essentially in the same plane, although fringe fields inhibit a homogeneous reorientation. This requires two transistors for each pixel instead of the single transistor needed for a standard thin-film transistor (TFT) display. The IPS technology is used in everything from televisions, computer monitors, and even wearable devices, especially almost all LCD smartphone panels are IPS/FFS mode. IPS displays belong to the LCD panel family screen types. The other two types are VA and TN. Before LG Enhanced IPS was introduced in 2001 by Hitachi as 17" monitor in Market, the additional transistors resulted in blocking more transmission area, thus requiring a brighter backlight and consuming more power, making this type of display less desirable for notebook computers. Panasonic Himeji G8.5 was using an enhanced version of IPS, also LGD in Korea, then currently the world biggest LCD panel manufacture BOE in China is also IPS/FFS mode TV panel.

In 2011, LG claimed the smartphone LG Optimus Black (IPS LCD (LCD NOVA)) has the brightness up to 700 nits, while the competitor has only IPS LCD with 518 nits and double an active-matrix OLED (AMOLED) display with 305 nits. LG also claimed the NOVA display to be 50 percent more efficient than regular LCDs and to consume only 50 percent of the power of AMOLED displays when producing white on screen.

This pixel-layout is found in S-IPS LCDs. A chevron shape is used to widen the viewing cone (range of viewing directions with good contrast and low color shift).

Vertical-alignment displays are a form of LCDs in which the liquid crystals naturally align vertically to the glass substrates. When no voltage is applied, the liquid crystals remain perpendicular to the substrate, creating a black display between crossed polarizers. When voltage is applied, the liquid crystals shift to a tilted position, allowing light to pass through and create a gray-scale display depending on the amount of tilt generated by the electric field. It has a deeper-black background, a higher contrast ratio, a wider viewing angle, and better image quality at extreme temperatures than traditional twisted-nematic displays.

Blue phase mode LCDs have been shown as engineering samples early in 2008, but they are not in mass-production. The physics of blue phase mode LCDs suggest that very short switching times (≈1 ms) can be achieved, so time sequential color control can possibly be realized and expensive color filters would be obsolete.

Some LCD panels have defective transistors, causing permanently lit or unlit pixels which are commonly referred to as stuck pixels or dead pixels respectively. Unlike integrated circuits (ICs), LCD panels with a few defective transistors are usually still usable. Manufacturers" policies for the acceptable number of defective pixels vary greatly. At one point, Samsung held a zero-tolerance policy for LCD monitors sold in Korea.ISO 13406-2 standard.

Dead pixel policies are often hotly debated between manufacturers and customers. To regulate the acceptability of defects and to protect the end user, ISO released the ISO 13406-2 standard,ISO 9241, specifically ISO-9241-302, 303, 305, 307:2008 pixel defects. However, not every LCD manufacturer conforms to the ISO standard and the ISO standard is quite often interpreted in different ways. LCD panels are more likely to have defects than most ICs due to their larger size. For example, a 300 mm SVGA LCD has 8 defects and a 150 mm wafer has only 3 defects. However, 134 of the 137 dies on the wafer will be acceptable, whereas rejection of the whole LCD panel would be a 0% yield. In recent years, quality control has been improved. An SVGA LCD panel with 4 defective pixels is usually considered defective and customers can request an exchange for a new one.

Some manufacturers, notably in South Korea where some of the largest LCD panel manufacturers, such as LG, are located, now have a zero-defective-pixel guarantee, which is an extra screening process which can then determine "A"- and "B"-grade panels.clouding (or less commonly mura), which describes the uneven patches of changes in luminance. It is most visible in dark or black areas of displayed scenes.

The zenithal bistable device (ZBD), developed by Qinetiq (formerly DERA), can retain an image without power. The crystals may exist in one of two stable orientations ("black" and "white") and power is only required to change the image. ZBD Displays is a spin-off company from QinetiQ who manufactured both grayscale and color ZBD devices. Kent Displays has also developed a "no-power" display that uses polymer stabilized cholesteric liquid crystal (ChLCD). In 2009 Kent demonstrated the use of a ChLCD to cover the entire surface of a mobile phone, allowing it to change colors, and keep that color even when power is removed.

In 2004, researchers at the University of Oxford demonstrated two new types of zero-power bistable LCDs based on Zenithal bistable techniques.e.g., BiNem technology, are based mainly on the surface properties and need specific weak anchoring materials.

Resolution The resolution of an LCD is expressed by the number of columns and rows of pixels (e.g., 1024×768). Each pixel is usually composed 3 sub-pixels, a red, a green, and a blue one. This had been one of the few features of LCD performance that remained uniform among different designs. However, there are newer designs that share sub-pixels among pixels and add Quattron which attempt to efficiently increase the perceived resolution of a display without increasing the actual resolution, to mixed results.

Spatial performance: For a computer monitor or some other display that is being viewed from a very close distance, resolution is often expressed in terms of dot pitch or pixels per inch, which is consistent with the printing industry. Display density varies per application, with televisions generally having a low density for long-distance viewing and portable devices having a high density for close-range detail. The Viewing Angle of an LCD may be important depending on the display and its usage, the limitations of certain display technologies mean the display only displays accurately at certain angles.

Temporal performance: the temporal resolution of an LCD is how well it can display changing images, or the accuracy and the number of times per second the display draws the data it is being given. LCD pixels do not flash on/off between frames, so LCD monitors exhibit no refresh-induced flicker no matter how low the refresh rate.

Color performance: There are multiple terms to describe different aspects of color performance of a display. Color gamut is the range of colors that can be displayed, and color depth, which is the fineness with which the color range is divided. Color gamut is a relatively straight forward feature, but it is rarely discussed in marketing materials except at the professional level. Having a color range that exceeds the content being shown on the screen has no benefits, so displays are only made to perform within or below the range of a certain specification.white point and gamma correction, which describe what color white is and how the other colors are displayed relative to white.

Brightness and contrast ratio: Contrast ratio is the ratio of the brightness of a full-on pixel to a full-off pixel. The LCD itself is only a light valve and does not generate light; the light comes from a backlight that is either fluorescent or a set of LEDs. Brightness is usually stated as the maximum light output of the LCD, which can vary greatly based on the transparency of the LCD and the brightness of the backlight. Brighter backlight allows stronger contrast and higher dynamic range (HDR displays are graded in peak luminance), but there is always a trade-off between brightness and power consumption.

Usually no refresh-rate flicker, because the LCD pixels hold their state between refreshes (which are usually done at 200 Hz or faster, regardless of the input refresh rate).

No theoretical resolution limit. When multiple LCD panels are used together to create a single canvas, each additional panel increases the total resolution of the display, which is commonly called stacked resolution.

As an inherently digital device, the LCD can natively display digital data from a DVI or HDMI connection without requiring conversion to analog. Some LCD panels have native fiber optic inputs in addition to DVI and HDMI.

As of 2012, most implementations of LCD backlighting use pulse-width modulation (PWM) to dim the display,CRT monitor at 85 Hz refresh rate would (this is because the entire screen is strobing on and off rather than a CRT"s phosphor sustained dot which continually scans across the display, leaving some part of the display always lit), causing severe eye-strain for some people.LED-backlit monitors, because the LEDs switch on and off faster than a CCFL lamp.

Only one native resolution. Displaying any other resolution either requires a video scaler, causing blurriness and jagged edges, or running the display at native resolution using 1:1 pixel mapping, causing the image either not to fill the screen (letterboxed display), or to run off the lower or right edges of the screen.

Fixed bit depth (also called color depth). Many cheaper LCDs are only able to display 262144 (218) colors. 8-bit S-IPS panels can display 16 million (224) colors and have significantly better black level, but are expensive and have slower response time.

Input lag, because the LCD"s A/D converter waits for each frame to be completely been output before drawing it to the LCD panel. Many LCD monitors do post-processing before displaying the image in an attempt to compensate for poor color fidelity, which adds an additional lag. Further, a video scaler must be used when displaying non-native resolutions, which adds yet more time lag. Scaling and post processing are usually done in a single chip on modern monitors, but each function that chip performs adds some delay. Some displays have a video gaming mode which disables all or most processing to reduce perceivable input lag.

Dead or stuck pixels may occur during manufacturing or after a period of use. A stuck pixel will glow with color even on an all-black screen, while a dead one will always remain black.

In a constant-on situation, thermalization may occur in case of bad thermal management, in which part of the screen has overheated and looks discolored compared to the rest of the screen.

Loss of brightness and much slower response times in low temperature environments. In sub-zero environments, LCD screens may cease to function without the use of supplemental heating.

The production of LCD screens uses nitrogen trifluoride (NF3) as an etching fluid during the production of the thin-film components. NF3 is a potent greenhouse gas, and its relatively long half-life may make it a potentially harmful contributor to global warming. A report in Geophysical Research Letters suggested that its effects were theoretically much greater than better-known sources of greenhouse gasses like carbon dioxide. As NF3 was not in widespread use at the time, it was not made part of the Kyoto Protocols and has been deemed "the missing greenhouse gas".

Kawamoto, H. (2012). "The Inventors of TFT Active-Matrix LCD Receive the 2011 IEEE Nishizawa Medal". Journal of Display Technology. 8 (1): 3–4. Bibcode:2012JDisT...8....3K. doi:10.1109/JDT.2011.2177740. ISSN 1551-319X.

Explanation of CCFL backlighting details, "Design News — Features — How to Backlight an LCD" Archived January 2, 2014, at the Wayback Machine, Randy Frank, Retrieved January 2013.

Energy Efficiency Success Story: TV Energy Consumption Shrinks as Screen Size and Performance Grow, Finds New CTA Study; Consumer Technology Association; press release 12 July 2017; https://cta.tech/News/Press-Releases/2017/July/Energy-Efficiency-Success-Story-TV-Energy-Consump.aspx Archived November 4, 2017, at the Wayback Machine

LCD Television Power Draw Trends from 2003 to 2015; B. Urban and K. Roth; Fraunhofer USA Center for Sustainable Energy Systems; Final Report to the Consumer Technology Association; May 2017; http://www.cta.tech/cta/media/policyImages/policyPDFs/Fraunhofer-LCD-TV-Power-Draw-Trends-FINAL.pdf Archived August 1, 2017, at the Wayback Machine

New Cholesteric Colour Filters for Reflective LCDs; C. Doornkamp; R. T. Wegh; J. Lub; SID Symposium Digest of Technical Papers; Volume 32, Issue 1 June 2001; Pages 456–459; http://onlinelibrary.wiley.com/doi/10.1889/1.1831895/full

K. H. Lee; H. Y. Kim; K. H. Park; S. J. Jang; I. C. Park & J. Y. Lee (June 2006). "A Novel Outdoor Readability of Portable TFT-LCD with AFFS Technology". SID Symposium Digest of Technical Papers. 37 (1): 1079–1082. doi:10.1889/1.2433159. S2CID 129569963.

Jack H. Park (January 15, 2015). "Cut and Run: Taiwan-controlled LCD Panel Maker in Danger of Shutdown without Further Investment". www.businesskorea.co.kr. Archived from the original on May 12, 2015. Retrieved April 23, 2015.

NXP Semiconductors (October 21, 2011). "UM10764 Vertical Alignment (VA) displays and NXP LCD drivers" (PDF). Archived from the original (PDF) on March 14, 2014. Retrieved September 4, 2014.

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Explanation of why pulse width modulated backlighting is used, and its side-effects, "Pulse Width Modulation on LCD monitors", TFT Central. Retrieved June 2012.

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This Tripod Stand Projector Screen is made of flame retardant fabric, which is also resistant to mildew and stain. It is simple to install and easy to extend with a practical carry handle is integrated on the housing. The product has a high quality surface for excellent flatness and outstanding image reproduction. The screen design for temporary or mobile display place such as small meeting room, exhibition place, shopping mall or hotel. Beautiful design and excellent visual effect can satisfy the customers" needs very well. Our Tripod Stand Projector Screen is sold well both at domestic and abroad, highly praised by customers for the superior quality and reasonable price. Please let us know if you are interested!

a line of extreme and ultra-narrow bezel LCD displays that provides a video wall solution for demanding requirements of 24x7 mission-critical applications and high ambient light environments

Many of our competitors use rolled vinyl made from a calender process (a series of hard pressure rollers) to make their screens. This same vinyl is used to make a host of other products including car seats, window roller shades, indoor and outdoor signage, tarps, tents and pond liners. Our screen materials are made for one sole purpose only; to give you the best possible image resolution, color fidelity, and uniformity — no matter your application or your venue. We pour our heart and soul into furnishing the best possible image fidelity in virtually any size. Our stated aspiration is to leave you completely awed by the picture quality.

Stewart Filmscreen is the only projection screen manufacturer to build unrivaled optical screen materials from the molecular level up. Our proprietary process involves a unique multi-layer system, allowing us to craft the perfect custom screen material for each unique venue. Our screen fabrics can receive as many as 13 optical layers — each providing a specific, optical quality, resulting in a picture perfect image. Our vertically integrated manufacturing process guarantees that you will receive a high performance screen fabric specifically formulated to serve the venue for many years.

We build seamless projection screens because our customers demand them. Why is this important? The longevity and image fidelity of the screen is greatly improved when seams are eliminated. “Virtually seamless” is not the same as seamless. We’ve all seen the opposite result — aging, shabby seams showing up in the content whenever key or brightly lit scenes are shown. With Stewart, you’ll never have any seams.

Tab-tensioning was developed by Stewart Filmscreen over forty years ago as a complement to the development of stressed roller tubes. Stewart’s stressed tubes enabled screen images to go wider than any previously deployed roller screens by employing a process known as tab-tensioning. The Stewart family had a lot of sailors back then and they knew from experience that a clew could be used to pull a sail out to a flat position, pulling against a luff rope. They took this principle and added luff cables and a weighted batten to a roller screen. We now call those luff lines, side cords and we use tabs to luff the screen outward. The side cords are curved so that each tab is equally tensioned from top to bottom. The end result is the widest possible screen image with a flat, even surface in the vertical direction.

The catenary curve forms a “virtual frame,” applying equal tension on all points of the screen. The stressed roller tube suspends the material across the top. The batten tensions the bottom edge. And equal tension is provided on the sides by the curved, tab-tensioning system. The catenary curve provides a perfectly flat image — up to 45 feet wide — with up to 25 feet of screen material descending from the ceiling. The best part? Touch a button and up it goes, freeing the room for other activities.

The determination of the use of front projection versus rear projection is an important early dichotomy in determining screen selection. Rear projection has some basic advantages in contrast rendition in varying, uncontrolled viewing conditions and also provides a unique ability to allow a presenter to stand in front of the screen without interrupting screen content. Rear projection via rigid screens also provides an artful separation of the viewing area from the projector and helps to isolate any noise. The principle disadvantage of rear projection is the need to dedicate an area behind the screen for the light path. Front projection is efficient in that the light path is shared with the viewing audience.

Room lighting varies, and without particular efforts in screen technology, contrast falls rapidly as room light increases. Stewart offers reference materials for well controlled spaces where ambient and re-reflected light is managed. Stewart has also pioneered special products to enhance contrast performance in ambient light. We offer matte gray surfaces as well as intensely-engineered metallic and hybrid metallic surfaces with our Phantom HALR and FireHawk products to provide contrast in difficult lighting environments. It is always important that a candid assessment of room lighting be a key component of your screen selection process.

Throw distance is typically not problematic for matte screens and many rear projection screens that are designed for short throw use. Longer throw distances are synergistic with products tailored to perform in high ambient light as well as for polarization preserving fabrics for 3D use. Longer throw distances normalize and reduce the standard deviation of the angle of incidence of projected light hitting the screen. As throw distance increases the light hits the screen in angles much closer to 90 degrees. This is helpful with the redistribution of light in the viewing area, greatly reducing the penalty in uniformity which a niche specific, ambient light rejecting screen must offer. In 3D presentation spaces, longer throws reduce double bounces of light on the screen surface, preserving stereoscopic vision for content separation and contrast.

The best seat will always vary from viewer to viewer. Some prefer the visual envelopment of the front of the house while others prefer to be more central. Stewart Filmscreen is very driven to make sure that each seat is as pleasing as possible. If compromises in quality from seat to seat must be made, Stewart will predict those outcomes and assist in preparing all vested parties with accurate information and ensure your expectations will be met.

Stewart Filmscreen is technology neutral with regard to projector types. We have the greatest respect for our partners in two-piece projection. We also pay close attention as tech evolves and we frequently collaborate with most leading projector companies. Many projector companies utilize our screens in their Q.C. and product development efforts. Currently, there is a lot of discussion about laser illuminant equipped projectors, and Stewart Filmscreen has been an eager partner for all participants in solid state illumination. We have exemplary products for laser projection — whether hybrid or phosphor wheel — and we have superb products for 3P/6P direct laser DCI compliant projectors.

Screen gain and half gain are measured in reference to specially developed pure white “gain standards” which are optical surfaces which reflect light in hemispheric, “Lambertian” distribution. Just about any surface can be manipulated to deliver specific results on-axis. It is a very different level of sophistication to control what happens off-axis. At Stewart, we hold ourselves to a standard of continuous monitoring and improvement in off-axis performance at all gain levels. Many competing fabrics drop the ball in off-axis performance resulting in hot spotting (a luminous, distracting and non-uniform ball of concentrated light) which follows the viewer regardless of position. Poor off-axis uniformity also results in color shift, a phenomena where colors change depending on viewer position.

Aspect ratios are dictated by projector technology, coupled with the source material to be displayed. At Stewart we furnish an endless array of screen configurations including retractable systems upon which any aspect ratio can be displayed. We also offer the world’s most advanced precision masking screen systems which include digital memories, allowing the viewer to select not only the proper aspect ratio, but also the capability to display that ratio at the scale most appropriate to the resolution of the content.

We take color very seriously. We have to. Our customers will not tolerate anything less. Our goal is to do no harm to the color space defined by content creators. We constantly measure our fabrics with exacting instruments to verify that proper color rendition is just a projector calibration away.

Stewart Filmscreen serves the most particular and demanding customers in any given niche of the audio visual market — the filmmaking industry. These professionals are not shy about what they expect and require from a projection screen. Filmmakers need to do their work without having any concerns that the screen itself is altering or skewing the results of their work. Post-production and presentation work is very costly and the screen needs to be a constant factor of quality which can be relied upon throughout the post-production process. We have carefully listened and have developed a unique grouping of reference quality, front projection screen fabrics in response to the continuous dialog we maintain with our most exacting customers. These screens are the reference screens for the Academy of Motion Pictures Arts and Sciences.

Matte white screens offer reference quality pictures in environments where ambient and re-reflected light sources are controlled. Not all matte screens are created equal. Variations in texture and surface gloss separate the high performers from the average offerings. Stewart Filmscreen makes matte white screens tailored for post-production clients who work long days in front of screens. These customers are an important, core market for Stewart Filmscreen. However, you don’t have to be in the movie business to enjoy reference viewing. We can help bring reference viewing to your own home.

Gray screens were pioneered by Stewart Filmscreen. Our early GrayMatte line was specifically engineered to preserve contrast in circular theme park and simulation environments. GrayHawk was developed to offer a near unity gain gray screen with enhanced contrast for home theater, calibrating properly for color rendition. Stewart has continued to improve these products and develop additional versions for larger formats. In rear projection, FilmScreen 100, offered at unity gain, and FilmScreen 150 which is 50% above unity, are both category leading screen fabrics for contrast preserving performance.

Stewart offers FireHawk G5, FireHawk LS, and Phantom HALR screen fabrics in high and ultra-high ambient light categories. These unique products are quite capable of preserving black levels and contrast. Stewart can offer these stellar fabrics in anything from a small, borderless version to a 45 foot wide retractable, perforated screen. The image to the right shows a 50/50 screen with Phantom HALR and SnoMatte 100 as shown in a room with high ambient light. We take great pride in the careful production of these charcoal screens and have found great success in their continued, high demand for venues which have uncontrollable levels of ambient light.

Silver screens are produced for 3D presentations utilizing polarized light to maintain separation between left and right eye content. Stewart Filmscreen offers two superb performers in this segment — Silver 3D, a higher gain iteration with exemplary stereoscopic separation and luminance recovery, and Silver 5D, a lower gain, wider viewing cone version which works best with shorter throws and with wider seating arrangements.

We offer optional screen perforation for realistic sound so you can place speakers behind the screen to create big theater sound in your own personal theater. During post-production audio film mixing, soundtracks are assigned to designated speakers with left, center and right channel speakers in the front, and surround sound speakers behind the viewer. As a result, the sound comes from where you expect it and the audio is aligned with the action sequences seen on the screen.

There is a lot of talk about 16K resolution. But, what really matters when we talk about 16K is the size of the display and how far away the viewer is from the display. The resolution ability of the human eye is constant. However, the eye’s ability to see intricate details changes significantly as you create distance and move away from the display. For instance, the level of detail you can see on a phone or laptop screen is very different from the level of detail you can see on a projected screen surface when viewed from the appropriate viewing distance. For front projection, all Stewart fabrics are capable of resolving in excess of 16K on a ten foot wide screen which is at least double what the human eye can resolve when viewed from the appropriate distance. For rear projection, Stewart Filmscreen serves simulation clients who are aggressively combining multiple projectors on single screen surfaces resulting in astounding pixel densities, reaching a minimum of six line pairs per millimeter.

Stewart Filmscreen was founded in Southern California — the home of the movie industry and the home of theme based entertainment. We embrace custom applications and we always have. We look forward to challenging custom designs because it’s in our DNA. We are a trusted partner for the most particular clients in the world. We execute and honor non-disclosure agreements with government contractors as well as private sector entities who are at the cutting edge of possibilities in imaging and color science. This is not a stretch for us, it’s everyday business. We can make it happen for you.

For multiview 3D display technologies, we will review occlusion-based technologies (parallax barrier, time-sequential aperture, moving slit, and cylindrical parallax barrier), refraction-based (lenticular sheet, multiprojector, prism, and integral imaging), reflection-based, diffraction-based, illumination-based, and projection-based 3D display mechanisms. We also briefly discuss recent developments in super-multiview and multiview with eye-tracking technologies.

For volumetric 3D display technologies, we will review static screen (solid-state upconversion, gas medium, voxel array, layered LCD stack, and crystal cube) and swept screen (rotating LED array, cathode ray sphere, varifocal mirror, rotating helix, and rotating flat screen). Both passive screens (no emitter) and active screens (with emitters on the screen) are discussed.

We also provide a section to discuss a few very popular “pseudo 3D display” technologies that are often mistakenly called holographic or true 3D displays and include on-stage telepresence, fog screens, graphic waterfalls, and virtual reality techniques, such as Vermeer from Microsoft.

Conventional 2D display devices, such as cathode ray tubes (CRTs), liquid crystal devices (LCDs), or plasma screens, often lead to ambiguity and confusion in high-dimensional data/graphics presentation due to lack of true depth cues. Even with the help of powerful 3D rendering software, complex data patterns or 3D objects displayed on 2D screens are still unable to provide spatial relationships or depth information correctly and effectively. Lack of true 3D display often jeopardizes our ability to truthfully visualize high-dimensional data that are frequently encountered in advanced scientific computing, computer aided design (CAD), medical imaging, and many other disciplines. Essentially, a 2D display apparatus must rely on humans’ ability to piece together a 3D representation of images. Despite the impressive mental capability of the human visual system, its visual perception is not reliable if certain depth cues are missing.

Figure 1 illustrates an example of an optical illusion that demonstrates how easy it is to mislead the human visual system in a 2D flat display. On the left of the figure are some bits and pieces of an object. They look like corners and sides of some 3D object. After putting them together, a drawing of a physically impossible object is formed in a 2D screen (right-hand side of Fig. 1). Notice that, however, there is nothing inherently impossible about the collection of 2D lines and angles that make up the 2D drawing. The reason for this optical illusion to occur is lack of proper depth cues in the 2D display system. To effectively overcome the illusion or confusion that often occurs in visualizing high-dimensional data/images, true volumetric 3D display systems that preserve most of the depth cues in an image are necessary.

What is a “perfect” 3D display? A perfect 3D display should function as a “window to the world” through which viewers can perceive the same 3D scene as if the 3D display screen were a transparent “window” to the real-world objects. Figure 2 illustrates the “window to the world” concept. In Fig. 2(a), a viewer looks at 3D objects in the world directly. We now place a 3D display screen between the viewer and the 3D scene. The 3D display device should be able to totally duplicate the entire visual sensation received by the viewer. In other words, a perfect 3D display should be able to offer all depth cues to its viewers [Fig. 2(b)].

What is a perfect 3D display? (a) A viewer looks at 3D scene directly. (b) A perfect 3D display should function as a “window to the world” through which viewers can perceive the same 3D scene as if the 3D display screen were a transparent “window” to the real world objects.

Computer graphics enhance our 3D sensation in viewing 3D objects. Although an enhanced 3D image appears to have depth or volume, it is still only 2D, due to the nature of the 2D display on a flat screen. The human visual system needs both physical and psychological depth cues to recognize the third dimension. Physical depth cues can be introduced only by true 3D objects; psychological cues can be evoked by 2D images.

Some 3D display devices can provide all of these physical depth cues, while other autostereoscopic 3D display techniques may not be able to provide all of these cues. For example, 3D movies based on stereo eyeglasses may cause eye fatigue due to the conflict of accommodation and convergence, since the displayed images are on the screen, not at their physical distance in 3D space [28].

Most 2D display screens produce pixels that are points emitting light of a particular color and brightness. They never take on a different brightness or color hue no matter how or from where they are viewed. This omnidirectional emission behavior prevents 2D display screens from producing a true 3D sensation.

Each element (voxel or hoxel) in a true 3D display should consist of multiple directional emitters: if tiny projectors radiate the captured light, the plenoptic function of the display is an approximation to that of the original scene when seen by an observer.

Since 1080p home theater projectors have dropped below $1,000, the demand for inexpensive screens is bigger than ever. When you spend less than $1,000 on a projector, you don"t want to spend big bucks on a screen to go with it. So for hobbyists with a creative, DIY bent, let"s focus on how to paint the perfect screen for under $100. We will look for a good paint solution because it is easy, cheap, and it doesn"t warp and ripple over time like fabric screens can do.

First, if we are going to build a great screen, we need a standard of perfection to compare it to. That, to us, is the Stewart Studiotek 100, a perfectly neutral 1.0 gain white screen that reflects back exactly what the projector puts out. It has absolutely no color bias, no gain, with a pure smooth finish that reflects the maximum amount of image detail. Since white paint will have a gain of about 1.0, the Studiotek 100 is a good benchmark against which to compare our results.

Many people are interested in gray screens and paints due to their increased black level. So we started our evaluation with the popular Behr Silver Screen formula. We painted a test board and mounted it in front of the Studiotek 100. Illuminating these two surfaces with a variety of test patterns and video clips revealed significant differences in contrast and color balance.

The one advantage the Behr Silver Screen had over the Studiotek 100 was black level, which is expected from gray paint--the darker the screen, the darker the black level. In scenes with a black background and white highlights such as rolling credits, the paint showed a higher contrast image and a much more solid black. The Behr Silver Screen is the perfect solution for people who watch rolling credits. Unfortunately, that"s not what 99% of one"s viewing subject matter consists of.

The Behr image was 27% dimmer than the Studiotek 100. That, in itself, is not a problem if you have a small enough screen or a bright enough projector. But the Behr Silver Screen kills color saturation, and it appears to reduce vibrancy in the warmer end of the spectrum. This should not be surprising. Imagine, what do you get when you mix gray with yellow? You get a grayish yellow. If you mix gray and blue you get a grayish blue. But the compromise of the yellow is more noticeable.

On the Behr gray paint, flesh tones looked horrible, appearing dirty or ash-colored in comparison to the Studiotek 100. Red and yellow color saturation is the most muted, and white highlights appear as subdued grays. Overall, the Behr Silver Screen paint does not deliver a balanced image. It certainly is not showing you what the projector is putting out. On its own, due to its increased black level, it may look fine if you don"t have anything to compare it to, and the deep black creates an impressive sense of contrast under the right circumstances. But it is not a paint we would recommend for optimum home theater performance.

Gray screens were invented to compensate for the low contrast projectors of years past. But with today"s high contrast models, we favor the use of white screens unless you have chronic uncontrolled ambient light. Since white paint should have a gain of about 1.0,