| Merchant mask shop |
A mask shop that sells the photomasks to external customers. |
| Metal Halide |
Superior lamp technology offering high brightness and longevity at extra cost. See also Quartz Halogen. |
| Module |
LCD glass connected to a PCB with drivers on board. It may also have controllers, temperature compensation circuits, or other features. |
| Multiplex |
Using multiple backplanes in order to reduce the number of connections between the LCD and the drivers. |
| Mura |
A key quality requirement for display photomasks is the absence of mura. Mura is caused by systematic deviations in the photomask and can be visible as stripes. Mura compromises the image quality of the finished display. Usually the deviations causing the mura are very small, below a few hundred nanometers. Deviations of that size spread over a large area can be difficult to detect by measuring. Still the human eye can see them due to its high sensitivity to systematic changes in gray scale. Micronic´s extensive experience of eliminating mura in photomasks is one of the key success factors behind the display pattern generators. |
| Native Resolution |
Unlike traditional CRTs that can display multiple resolutions, LCD displays are manufactured to best display a single resolution, known as the native resolution. While it may be possible to change the resolution of an LCD (depending on the video card and software used with the LCD), setting the resolution to something other than the native resolution will result in a stretched image, a blurry image, or no image on the screen at all. |
| Nematic |
Describes a liquid crystal material whose elongated molecules rest parallel to each other but are not in layers. |
| NIT |
Measure of brightness properly called candela per meter square (cd/m2); equal to 1 cd/m2 or 0.292 ftL. |
| Normally Black |
A twisted nematic LCD design where the backlight is blocked when pixels are in the unselected state. Therefore, when no voltage is applied, the screen is black. |
| Normally White |
A twisted nematic LCD design where light is transmitted when pixels are in the unselected state. Therefore, when no voltage is applied, the screen is white. |
| NTSC |
The 525-line American colour TV format as specified by the National Television Systems Committee. |
| PAL |
The Phase Alternate by Line colour TV format used in the UK and in most of Europe, where each frame has 625 lines comprised of two interlaced fields. |
| Passive |
A technique by which each row and column of the display are multiplexed or addressed in turn ( also called duty type ). |
| Passive Matrix |
LCD design which does not have a transistor in each subpixel. Subpixels are switched entirely by row and column driver ICs. |
| Persistence |
The time it takes for the visible glow of a CRT's phosphor to darken after the scanning electron beam is removed. A long persistence means less flicker, but may create smearing when images are in motion. |
| Phosphor |
The coating on the inside of CRTs. Phosphor glows when struck with electrons. Images appear on a CRT by controlled scanning of an electron beam. |
| Photomask |
Can be described as a photo negative. The image on the negative is written with Micronic´s pattern generator. In the production of the end product, e.g. IC or FPD, the image on the photomask is transferred to the substrate via a photographic process. There are two types of microlithographic photomasks: standard photo emulsion on glass and chrome on glass. The photosensitive material on the chrome photomask is a layer of photoresist covering the chrome layer. Photoresist is a light sensitive material with properties such that it can be washed away after exposure. |
| Pitch |
Center dimension of adjacent conductive traces, dots, or connector holes. |
| Pixel |
Pixels are tiny picture elements comprised of three subpixels (one red, one green, and one blue.) Although a single pixel displays one color, collectively those pixels create a complete image recognizable by the human eye. A single LCD consists of thousands, even millions of pixels. |
| Pixel Anomaly |
A pixel anomaly is a pixel that displays only one color (white, black, red, green, or blue.) These are commonly referred to as "stuck" or "void" pixels. If a pixel on an LCD appears to be stuck on one color, it will sometimes come back to life by gently massaging the pixel and the area surrounding it in a circular pattern. A small number of pixel anomalies are considered normal, or at least inevitable, on LCDs. The number of pixel anomalies it takes for a display to be considered defective varies by hardware manufacturer. |
| Plasma Display Panels (PDP) |
PDPs use helium, neon and xenon gases, which are placed between two glass substrates. The gases are then activated with accelerated electrons, causing them to produce ultraviolet rays which simulate red, green and blue fluorescent materials at each pixel. PDP technology requires higher power and can be used in applications that do not have such stringent weight requirements while offering the obvious advantages of being thin and flat. Additionally, PDPs provide a better viewing angle. |
| PM-LCD |
(Passive Matrix Liquid Crystal Display) An LCD technology where the pixels have no internal drive transistors (cf. TFT-LCD). This is used for applications where the quality requirements are lower or the size is small. Typical applications include mobile phones and handheld electronic games. The photomasks required for PM-LCD have lower requirements than for TFT-LCD since there are no small transistors in the pattern. |
| Polarizer |
A light filter which only allows light waves of a certain rotation through. Polarized material with perpendicular filtering is used in LCDs to enclose the liquid crystal. The liquid crystal is then used as the medium which twists the light waves 90° in order to allow the light to pass through or not. |
| Polysilicon |
Newer LCD panel material that offers better performance and colour contrast than TFT. Usually requires three panels per projection device (Red, Green & Blue) and consequently tends to be more expensive. See also Amorphous TFT. |
| Portrait |
A page or screen orientation that is taller than it is wide. |
Glossary
