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51-540: While STN displays were once common in various electronic devices, they have been largely replaced by TFT (thin-film transistor) displays. In 1982, C. M. Waters and E. P. Raynes patented STN displays, and by 1984 researchers at Brown Boveri (later ABB ) built the first prototype STN matrix display, with 540 × 270 pixels. A key challenge was finding a way to address more pixels efficiently. Standard TN displays weren't ideal for this because of their voltage characteristics. STN displays, with their 180-270 degree twist, offered

102-536: A glass panel. The silicon layer for TFT-LCDs is typically deposited using the PECVD process. Transistors take up only a small fraction of the area of each pixel and the rest of the silicon film is etched away to allow light to easily pass through it. Polycrystalline silicon is sometimes used in displays that require higher TFT performance. Examples include small high-resolution displays such as those found in projectors or viewfinders. Amorphous silicon-based TFTs are by far

153-418: A voltage can be easily applied across just one segment of these types of displays without interfering with the other segments. This would be impractical for a large display , because it would have a large number of (color) picture elements ( pixels ), and thus it would require millions of connections, both top and bottom for each one of the three colors (red, green and blue) of every pixel. To avoid this issue,

204-487: A 2-by-18 matrix display driven by a hybrid circuit using the dynamic scattering mode of LCDs. In 1973, T. Peter Brody , J. A. Asars and G. D. Dixon at Westinghouse Research Laboratories developed a CdSe ( cadmium selenide ) TFT, which they used to demonstrate the first CdSe thin-film-transistor liquid-crystal display (TFT LCD). Brody and Fang-Chen Luo demonstrated the first flat active-matrix liquid-crystal display (AM LCD) using CdSe TFTs in 1974, and then Brody coined

255-407: A 3.1-megapixel image. The image would be a very low quality image (72ppi) if printed at about 28.5 inches wide, but a very good quality (300ppi) image if printed at about 7 inches wide. The number of photodiodes in a color digital camera image sensor is often a multiple of the number of pixels in the image it produces, because information from an array of color image sensors is used to reconstruct

306-433: A TFT LCD feature one or more analog VGA , DVI , HDMI , or DisplayPort interface, with many featuring a selection of these interfaces. Inside external display devices there is a controller board that will convert the video signal using color mapping and image scaling usually employing the discrete cosine transform (DCT) in order to convert any video source like CVBS , VGA , DVI , HDMI , etc. into digital RGB at

357-477: A digital video signal at the resolution determined by the panel pixel matrix designed at manufacture. Some screen panels will ignore the LSB bits of the color information to present a consistent interface (8 bit -> 6 bit/color x3). With analogue signals like VGA, the display controller also needs to perform a high speed analog to digital conversion. With digital input signals like DVI or HDMI some simple reordering of

408-402: A layer of insulating liquid crystal sandwiched between transparent conductive layers of indium tin oxide (ITO) . The circuit layout process of a TFT-LCD is very similar to that of semiconductor products. However, rather than fabricating the transistors from silicon , that is formed into a crystalline silicon wafer, they are made from a thin film of amorphous silicon that is deposited on

459-430: A low contrast ratio but later revisions have made marked improvements to these shortcomings. Because of its wide viewing angle and accurate color reproduction (with almost no off-angle color shift), IPS is widely employed in high-end monitors aimed at professional graphic artists, although with the recent fall in price it has been seen in the mainstream market as well. IPS technology was sold to Panasonic by Hitachi. This

510-687: A number of serial transmission lines synchronized to a clock whose rate is equal to the pixel rate. LVDS transmits seven bits per clock per data line, with six bits being data and one bit used to signal if the other six bits need to be inverted in order to maintain DC balance. Low-cost TFT displays often have three data lines and therefore only directly support 18 bits per pixel . Upscale displays have four or five data lines to support 24 bits per pixel ( truecolor ) or 30 bits per pixel respectively. Panel manufacturers are slowly replacing LVDS with Internal DisplayPort and Embedded DisplayPort, which allow sixfold reduction of

561-421: A particle's coordinates imposed by the measurement or existence of information regarding its momentum to any degree of precision. This fundamental limitation can, in turn, be a factor in the maximum imaging resolution at subatomic scales, as can be encountered using scanning electron microscopes . Radiometric resolution determines how finely a system can represent or distinguish differences of intensity , and

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612-479: A patent for a thin film MOSFET . Paul K. Weimer , also of RCA , implemented Wallmark's ideas and developed the thin-film transistor (TFT) in 1962, a type of MOSFET distinct from the standard bulk MOSFET. It was made with thin films of cadmium selenide and cadmium sulfide . The idea of a TFT-based liquid-crystal display (LCD) was conceived by Bernard Lechner of RCA Laboratories in 1968. In 1971, Lechner, F. J. Marlowe, E. O. Nester and J. Tults demonstrated

663-592: A secondary transistor gate in the single TFT cell to maintain the display of a pixel during a period of 1s without loss of image or without degrading the TFT transistors over time. By slowing the refresh rate of the standard frequency from 60 Hz to 1 Hz, DTP claims to increase the power efficiency by multiple orders of magnitude. Due to the very high cost of building TFT factories, there are few major OEM panel vendors for large display panels. The glass panel suppliers are as follows: External consumer display devices like

714-692: A solution. This twist allows for a clearer distinction between on and off states, making them suitable for passive-matrix addressing with more pixels. The main advantage of STN LCDs is their lower power consumption and affordability. They can also be made purely reflective for sunlight readability. In the late 1980s, they were used in portable computers and handheld devices like the Nintendo Game Boy . While still found in some simple digital products like calculators, STN displays have largely been replaced by TFT LCDs, which offer superior image quality and faster response times. CSTN (color super-twist nematic)

765-423: Is a color variant of STN displays, developed by Sharp . It uses red, green, and blue filters to create color images. Early CSTN displays had limitations like slow response times and ghosting. However, advancements have improved response times to 100 ms (still longer than the 8 ms for TFT), widened viewing angles to 140 degrees, and enhanced color quality, making them a more competitive option at about half

816-472: Is a list of traditional, analogue horizontal resolutions for various media. The list only includes popular formats, not rare formats, and all values are approximate, because the actual quality can vary machine-to-machine or tape-to-tape. For ease-of-comparison, all values are for the NTSC system. (For PAL systems, replace 480 with 576.) Analog formats usually had less chroma resolution. Many cameras and displays offset

867-721: Is also called CPA mode. A technology developed by Samsung is Super PLS, which bears similarities to IPS panels, has wider viewing angles, better image quality, increased brightness, and lower production costs. PLS technology debuted in the PC display market with the release of the Samsung S27A850 and S24A850 monitors in September 2011. TFT dual-transistor pixel or cell technology is a reflective-display technology for use in very-low-power-consumption applications such as electronic shelf labels (ESL), digital watches, or metering. DTP involves adding

918-538: Is an active matrix LCD, in contrast to passive matrix LCDs or simple, direct-driven (i.e. with segments directly connected to electronics outside the LCD) LCDs with a few segments. TFT LCDs are used in television sets , computer monitors , mobile phones , video game systems, personal digital assistants , navigation systems , projectors , and dashboards in some automobiles and in medium to high end motorcycles . In February 1957, John Wallmark of RCA filed

969-445: Is an LCD technology derived from the IPS by Boe-Hydis of Korea. Known as fringe field switching (FFS) until 2003, advanced fringe field switching is a technology similar to IPS or S-IPS offering superior performance and color gamut with high luminosity. Color shift and deviation caused by light leakage is corrected by optimizing the white gamut, which also enhances white/grey reproduction. AFFS

1020-474: Is an illustration of how the same image might appear at different pixel resolutions, if the pixels were poorly rendered as sharp squares (normally, a smooth image reconstruction from pixels would be preferred, but for illustration of pixels, the sharp squares make the point better). [REDACTED] An image that is 2048 pixels in width and 1536 pixels in height has a total of 2048×1536 = 3,145,728 pixels or 3.1 megapixels. One could refer to it as 2048 by 1536 or

1071-491: Is called spatial resolution, and it depends on properties of the system creating the image, not just the pixel resolution in pixels per inch (ppi). For practical purposes the clarity of the image is decided by its spatial resolution, not the number of pixels in an image. In effect, spatial resolution is the number of independent pixel values per unit length. The spatial resolution of consumer displays ranges from 50 to 800 pixel lines per inch. With scanners, optical resolution

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1122-455: Is developed by Hydis Technologies Co., Ltd, Korea (formally Hyundai Electronics, LCD Task Force). In 2004, Hydis Technologies Co., Ltd licensed its AFFS patent to Japan's Hitachi Displays. Hitachi is using AFFS to manufacture high end panels in their product line. In 2006, Hydis also licensed its AFFS to Sanyo Epson Imaging Devices Corporation. Hydis introduced AFFS+ which improved outdoor readability in 2007. It achieved pixel response which

1173-409: Is often considered equivalent to pixel count in digital imaging , though international standards in the digital camera field specify it should instead be called "Number of Total Pixels" in relation to image sensors, and as "Number of Recorded Pixels" for what is fully captured. Hence, CIPA DCG-001 calls for notation such as "Number of Recorded Pixels 1000 × 1500". According to the same standards,

1224-541: Is sometimes used to distinguish spatial resolution from the number of pixels per inch. In remote sensing , spatial resolution is typically limited by diffraction , as well as by aberrations, imperfect focus, and atmospheric distortion. The ground sample distance (GSD) of an image, the pixel spacing on the Earth's surface, is typically considerably smaller than the resolvable spot size. In astronomy , one often measures spatial resolution in data points per arcsecond subtended at

1275-435: Is the precision of a measurement with respect to time. Movie cameras and high-speed cameras can resolve events at different points in time. The time resolution used for movies is usually 24 to 48 frames per second (frames/s), whereas high-speed cameras may resolve 50 to 300 frames/s, or even more. The Heisenberg uncertainty principle describes the fundamental limit on the maximum spatial resolution of information about

1326-443: Is toxic. High-resolution Image resolution is the level of detail of an image . The term applies to digital images, film images, and other types of images. "Higher resolution" means more image detail. Image resolution can be measured in various ways. Resolution quantifies how close lines can be to each other and still be visibly resolved . Resolution units can be tied to physical sizes (e.g. lines per mm, lines per inch), to

1377-430: Is usually expressed as a number of levels or a number of bits , for example 8 bits or 256 levels that is typical of computer image files. The higher the radiometric resolution, the better subtle differences of intensity or reflectivity can be represented, at least in theory. In practice, the effective radiometric resolution is typically limited by the noise level, rather than by the number of bits of representation. This

1428-479: The "Number of Effective Pixels" that an image sensor or digital camera has is the count of pixel sensors that contribute to the final image (including pixels not in said image but nevertheless support the image filtering process), as opposed to the number of total pixels , which includes unused or light-shielded pixels around the edges. An image of N pixels height by M pixels wide can have any resolution less than N lines per picture height, or N TV lines. But when

1479-676: The 16.7 million color shades (24-bit truecolor ) that are available using 24-bit color. Instead, these panels display interpolated 24-bit color using a dithering method that combines adjacent pixels to simulate the desired shade. They can also use a form of temporal dithering called Frame Rate Control (FRC), which cycles between different shades with each new frame to simulate an intermediate shade. Such 18 bit panels with dithering are sometimes advertised as having "16.2 million colors". These color simulation methods are noticeable to many people and highly bothersome to some. FRC tends to be most noticeable in darker tones, while dithering appears to make

1530-458: The NTSC color gamut, a difference that is easily seen by the human eye. The transmittance of a pixel of an LCD panel typically does not change linearly with the applied voltage, and the sRGB standard for computer monitors requires a specific nonlinear dependence of the amount of emitted light as a function of the RGB value. In-plane switching (IPS) was developed by Hitachi in 1996 to improve on

1581-521: The bits is needed before feeding it to the rescaler if the input resolution does not match the display panel resolution. Liquid crystals are constantly subjected to toxicity and eco-toxicity testing for any hazard potential. The result is that: The statements are applicable to Merck KGaA as well as its competitors JNC Corporation (formerly Chisso Corporation) and DIC (formerly Dainippon Ink & Chemicals). All three manufacturers have agreed not to introduce any acutely toxic or mutagenic liquid crystals to

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1632-575: The color of a single pixel. The image has to be interpolated or demosaiced to produce all three colors for each output pixel. The terms blurriness and sharpness are used for digital images but other descriptors are used to reference the hardware capturing and displaying the images. Spatial resolution in radiology is the ability of the imaging modality to differentiate two objects. Low spatial resolution techniques will be unable to differentiate between two objects that are relatively close together. The measure of how closely lines can be resolved in an image

1683-497: The cost of TFT displays. A newer passive-matrix technology, high-performance addressing (HPA), offers even better performance than CSTN. Other STN display variations were introduced, attempting to improve image quality and response times. They include: TFT LCD A thin-film-transistor liquid-crystal display ( TFT LCD ) is a type of liquid-crystal display that uses thin-film-transistor technology to improve image qualities such as addressability and contrast. A TFT LCD

1734-408: The hardware capturing and displaying the images. Spectral resolution is the ability to resolve spectral features and bands into their separate components. Color images distinguish light of different spectra . Multispectral images can resolve even finer differences of spectrum or wavelength by measuring and storing more than the traditional 3 of common RGB color images. Temporal resolution (TR)

1785-567: The individual pixels of the LCD visible. Overall, color reproduction and linearity on TN panels is poor. Shortcomings in display color gamut (often referred to as a percentage of the NTSC 1953 color gamut ) are also due to backlighting technology. It is common for older displays to range from 10% to 26% of the NTSC color gamut, whereas other kind of displays, utilizing more complicated CCFL or LED phosphor formulations or RGB LED backlights, may extend past 100% of

1836-442: The latter (although more difficult to achieve) is key to visualizing how individual atoms interact. In Stereoscopic 3D images, spatial resolution could be defined as the spatial information recorded or captured by two viewpoints of a stereo camera (left and right camera). Pixel encoding limits the information stored in a digital image, and the term color profile is used for digital images but other descriptors are used to reference

1887-525: The market. They cover more than 90 percent of the global liquid crystal market. The remaining market share of liquid crystals, produced primarily in China, consists of older, patent-free substances from the three leading world producers and have already been tested for toxicity by them. As a result, they can also be considered non-toxic. The complete report is available from Merck KGaA online. The CCFL backlights used in many LCD monitors contain mercury , which

1938-458: The most common, due to their lower production cost, whereas polycrystalline silicon TFTs are more costly and much more difficult to produce. The twisted nematic (TN) display is one of the oldest and frequently cheapest kind of liquid crystal display technologies. TN displays have fast pixel response times and less smearing than other types of LCDs like IPS displays , but suffer from poor color reproduction and limited viewing angles, especially in

1989-441: The native resolution of the display panel. In a laptop the graphics chip will directly produce a signal suitable for connection to the built-in TFT display. A control mechanism for the backlight is usually included on the same controller board. The low level interface of STN , DSTN , or TFT display panels use either single ended TTL 5 V signal for older displays or TTL 3.3 V for slightly newer displays that transmits

2040-426: The number of differential pairs. Backlight intensity is usually controlled by varying a few volts DC, or generating a PWM signal, or adjusting a potentiometer or simply fixed. This in turn controls a high-voltage ( 1.3 kV ) DC-AC inverter or a matrix of LEDs . The method to control the intensity of LED is to pulse them with PWM which can be source of harmonic flicker. The bare display panel will only accept

2091-456: The off state. The bottom sub-pixel has continuously covered electrodes, while the upper one has a smaller area electrode in the center of the subpixel. When the field is on, the liquid crystal molecules start to tilt towards the center of the sub-pixels because of the electric field; as a result, a continuous pinwheel alignment (CPA) is formed; the azimuthal angle rotates 360 degrees continuously resulting in an excellent viewing angle. The ASV mode

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2142-455: The off-angle gamma shift. Some high-end Sony BRAVIA LCD TVs offer 10-bit and xvYCC color support, for example, the Bravia X4500 series. S-PVA also offers fast response times using modern RTC technologies. Advanced super view, also called axially symmetric vertical alignment was developed by Sharp . It is a VA mode where liquid crystal molecules orient perpendicular to the substrates in

2193-549: The overall size of a picture (lines per picture height, also known simply as lines, TV lines, or TVL), or to angular subtense. Instead of single lines, line pairs are often used, composed of a dark line and an adjacent light line; for example, a resolution of 10 lines per millimeter means 5 dark lines alternating with 5 light lines, or 5 line pairs per millimeter (5 LP/mm). Photographic lens are most often quoted in line pairs per millimeter. The resolution of digital cameras can be described in many different ways. The term resolution

2244-486: The pixel clock, horizontal sync , vertical sync , digital red, digital green, digital blue in parallel. Some models (for example the AT070TN92) also feature input/display enable , horizontal scan direction and vertical scan direction signals. New and large (>15") TFT displays often use LVDS signaling that transmits the same contents as the parallel interface (Hsync, Vsync, RGB) but will put control and RGB bits into

2295-814: The pixel counts are referred to as "resolution", the convention is to describe the pixel resolution with the set of two positive integer numbers, where the first number is the number of pixel columns (width) and the second is the number of pixel rows (height), for example as 7680 × 6876 . Another popular convention is to cite resolution as the total number of pixels in the image, typically given as number of megapixels , which can be calculated by multiplying pixel columns by pixel rows and dividing by one million. Other conventions include describing pixels per length unit or pixels per area unit, such as pixels per inch or per square inch. None of these pixel resolutions are true resolutions , but they are widely referred to as such; they serve as upper bounds on image resolution. Below

2346-401: The pixels are addressed in rows and columns, reducing the connection count from millions down to thousands. The column and row wires attach to transistor switches, one for each pixel. The one-way current passing characteristic of the transistor prevents the charge that is being applied to each pixel from being drained between refreshes to a display's image. Each pixel is a small capacitor with

2397-585: The point of observation, because the physical distance between objects in the image depends on their distance away and this varies widely with the object of interest. On the other hand, in electron microscopy , line or fringe resolution is the minimum separation detectable between adjacent parallel lines (e.g. between planes of atoms), whereas point resolution is instead the minimum separation between adjacent points that can be both detected and interpreted e.g. as adjacent columns of atoms, for instance. The former often helps one detect periodicity in specimens, whereas

2448-466: The poor viewing angle and the poor color reproduction of TN panels at that time. Its name comes from the main difference from TN panels, that the crystal molecules move parallel to the panel plane instead of perpendicular to it. This change reduces the amount of light scattering in the matrix, which gives IPS its characteristic wide viewing angles and good color reproduction. Initial iterations of IPS technology were characterised by slow response time and

2499-506: The term "active matrix" in 1975. By 2013, most modern high-resolution and high-quality electronic visual display devices used TFT-based active matrix displays. As of 2024, TFT LCD displays are still dominant, but compete with OLED for high brightness and high resolution displays, and compete with electronic paper for low power displays. The liquid crystal displays used in calculators and other devices with similarly simple displays have direct-driven image elements, and therefore

2550-645: The vertical direction. When viewed at an angle that is not perpendicular to the display, colors will shift, sometimes to the point of completely inverting. Modern, high end consumer products have developed methods to overcome the technology's shortcomings, such as RTC (Response Time Compensation / Overdrive) technologies . Modern TN displays can look significantly better than older TN displays from decades earlier, but overall TN has inferior viewing angles and poor color in comparison to other technology like IPS. Most TN panels can represent colors using only six bits per RGB channel, or 18 bit in total, and are unable to display

2601-848: Was fast for its time, wide viewing angles, and high contrast at the cost of brightness and color reproduction. Modern MVA panels can offer wide viewing angles (second only to S-IPS technology), good black depth, good color reproduction and depth, and fast response times due to the use of RTC ( Response Time Compensation ) technologies. When MVA panels are viewed off-perpendicular, colors will shift, but much less than for TN panels. There are several "next-generation" technologies based on MVA, including AU Optronics' P-MVA and AMVA , as well as Chi Mei Optoelectronics' S-MVA . Less expensive PVA panels often use dithering and FRC , whereas super-PVA (S-PVA) panels all use at least 8 bits per color component and do not use color simulation methods. S-PVA also largely eliminated off-angle glowing of solid blacks and reduced

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