Large-screen television technology

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Large-screen_television_technology 

56 inch DLP rear-projection TV

 

Large-screen television technology (colloquially big-screen TV) developed rapidly in the late 1990s and 2000s. Previously, a video display that used large-screen television technology was called a jumbotron and was used at stadiums and concerts. Various thin-screen technologies are being developed, but only liquid crystal display (LCD), plasma display (PDP) and Digital Light Processing (DLP) have been released on the public market. However, recently released technologies like organic light-emitting diode (OLED), and not-yet-released technologies like surface-conduction electron-emitter display (SED) or field emission display (FED), are on their way to replacing the first flat-screen technologies in picture quality.

These technologies have almost completely displaced cathode ray tubes (CRT) in television sales, due to the necessary bulkiness of cathode ray tubes. The diagonal screen size of a CRT television is limited to about 40 inches because of the size requirements of the cathode ray tube, which fires three beams of electrons onto the screen, creating a viewable image. A larger screen size requires a longer tube, making a CRT television with a large screen (50 to 80 inches diagonally) unrealistic. The new technologies can produce large-screen televisions that are much thinner.

Viewing distances

Horizontal, vertical and diagonal field of view

Before deciding on a particular display technology size, it is very important to determine from what distances it is going to be viewed. As the display size increases so does the ideal viewing distance. Bernard J. Lechner, while working for RCA, studied the best viewing distances for various conditions and derived the so-called Lechner distance.

As a rule of thumb, the viewing distance should be roughly two to three times the screen size for standard definition (SD) displays.

Screen size (in)	Viewing distance (ft)	Viewing distance (m)
15–26	5–8	1.5-2.4
26–32	8–11.5	2.4-3.5
32–42	11.5–13	3.5-4
42–55	>13	>4

Display specifications

The following are important factors for evaluating television displays:

• Display size: the diagonal length of the display.
• Display resolution: the number of pixels in each dimension on a display. In general a higher resolution will yield a clearer, sharper image.
• Dot pitch: This is the size of an individual pixel, which includes the length of the subpixels and distances between subpixels. It can be measured as the horizontal or diagonal length of a pixel. A smaller dot pitch generally results in sharper images because there are more pixels in a given area. In the case of CRT based displays, pixels are not equivalent to the phosphor dots, as they are to the pixel triads in LC displays. Projection displays that use three monochrome CRTs do not have a dot structure, so this specification does not apply.
• Response time: The time it takes for the display to respond to a given input. For an LC display it is defined as the total time it takes for a pixel to transition from black to white, and then white to black. A display with slow response times displaying moving pictures may result in blurring and distortion. Displays with fast response times can make better transitions in displaying moving objects without unwanted image artefacts.
• Brightness: The amount of light emitted from the display. It is sometimes synonymous with the term luminance, which is defined as the amount of light per area and is measured in SI units as candela per square meter.
• Contrast ratio: The ratio of the luminance of the brightest color to the luminance of the darkest color on the display. High contrast ratios are desirable but the method of measurement varies greatly. It can be measured with the display isolated from its environment or with the lighting of the room being accounted for. Static contrast ratio is measured on a static image at some instant in time. Dynamic contrast ratio is measured on the image over a period of time. Manufacturers can market either static or dynamic contrast ratio depending on which one is higher.
• Aspect ratio: The ratio of the display width to the display height. The aspect ratio of a traditional television is 4:3, which is being discontinued; the television industry is currently changing to the 16:9 ratio typically used by large-screen, high-definition televisions.
• Viewing angle: The maximum angle at which the display can be viewed with acceptable quality. The angle is measured from one direction to the opposite direction of the display, such that the maximum viewing angle is 180 degrees. Outside of this angle the viewer will see a distorted version of the image being displayed. The definition of what is acceptable quality for the image can be different among manufacturers and display types. Many manufacturers define this as the point at which the luminance is half of the maximum luminance. Some manufacturers define it based on contrast ratio and look at the angle at which a certain contrast ratio is realized.
• Color reproduction/gamut: The range of colors that the display can accurately represent.

Display technologies

LCD television

A pixel on an LCD consists of multiple layers of components: two polarizing filters, two glass plates with electrodes, and liquid crystal molecules. The liquid crystals are sandwiched between the glass plates and are in direct contact with the electrodes. The two polarizing filters are the outer layers in this structure. The polarity of one of these filters is oriented horizontally, while the polarity of the other filter is oriented vertically. The electrodes are treated with a layer of polymer to control the alignment of liquid crystal molecules in a particular direction. These rod-like molecules are arranged to match the horizontal orientation on one side and the vertical orientation on the other, giving the molecules a twisted, helical structure. Twisted nematic liquid crystals are naturally twisted, and are commonly used for LCDs because they react predictably to temperature variation and electric current.

When the liquid crystal material is in its natural state, light passing through the first filter will be rotated (in terms of polarity) by the twisted molecule structure, which allows the light to pass through the second filter. When voltage is applied across the electrodes, the liquid crystal structure is untwisted to an extent determined by the amount of voltage. A sufficiently large voltage will cause the molecules to untwist completely, such that the polarity of any light passing through will not be rotated and will instead be perpendicular to the filter polarity. This filter will block the passage of light because of the difference in polarity orientation, and the resulting pixel will be black. The amount of light allowed to pass through at each pixel can be controlled by varying the corresponding voltage accordingly. In a color LCD each pixel consists of red, green, and blue subpixels, which require appropriate color filters in addition to the components mentioned previously. Each subpixel can be controlled individually to display a large range of possible colors for a particular pixel.

The electrodes on one side of the LCD are arranged in columns, while the electrodes on the other side are arranged in rows, forming a large matrix that controls every pixel. Each pixel is designated a unique row-column combination, and the pixel can be accessed by the control circuits using this combination. These circuits send charge down the appropriate row and column, effectively applying a voltage across the electrodes at a given pixel. Simple LCDs such as those on digital watches can operate on what is called a passive-matrix structure, in which each pixel is addressed one at a time. This results in extremely slow response times and poor voltage control. A voltage applied to one pixel can cause the liquid crystals at surrounding pixels to untwist undesirably, resulting in fuzziness and poor contrast in this area of the image. LCDs with high resolutions, such as large-screen LCD televisions, require an active-matrix structure. This structure is a matrix of thin-film transistors, each corresponding to one pixel on the display. The switching ability of the transistors allows each pixel to be accessed individually and precisely, without affecting nearby pixels. Each transistor also acts as a capacitor while leaking very little current, so it can effectively store the charge while the display is being refreshed.

The following are types of LC display technologies:

• Twisted Nematic (TN): This type of display is the most common and makes use of twisted nematic-phase crystals, which have a natural helical structure and can be untwisted by an applied voltage to allow light to pass through. These displays have low production costs and fast response times but also limited viewing angles, and many have a limited color gamut that cannot take full advantage of advanced graphics cards. These limitations are due to variation in the angles of the liquid crystal molecules at different depths, restricting the angles at which light can leave the pixel.
• In-Plane Switching (IPS): Unlike the electrode arrangement in traditional TN displays, the two electrodes corresponding to a pixel are both on the same glass plate and are parallel to each other. The liquid crystal molecules do not form a helical structure and instead are also parallel to each other. In its natural or "off" state, the molecule structure is arranged parallel to the glass plates and electrodes. Because the twisted molecule structure is not used in an IPS display, the angle at which light leaves a pixel is not as restricted, and therefore viewing angles and color reproduction are much improved compared to those of TN displays. However, IPS displays have slower response times. IPS displays also initially suffered from poor contrast ratios but has been significantly improved with the development of Advanced Super IPS (AS – IPS).
• Multi-Domain Vertical Alignment (MVA): In this type of display the liquid crystals are naturally arranged perpendicular to the glass plates but can be rotated to control light passing through. There are also pyramid-like protrusions in the glass substrates to control the rotation of the liquid crystals such that the light is channeled at an angle with the glass plate. This technology results in wide viewing angles while boasting good contrast ratios and faster response times than those of TN and IPS displays. The major drawback is a reduction in brightness.
• Patterned Vertical Alignment (PVA): This type of display is a variation of MVA and performs very similarly, but with much higher contrast ratios.

Plasma display

Composition of plasma display panel

A plasma display is made up of many thousands of gas-filled cells that are sandwiched in between two glass plates, two sets of electrodes, dielectric material, and protective layers. The address electrodes are arranged vertically between the rear glass plate and a protective layer. This structure sits behind the cells in the rear of the display, with the protective layer in direct contact with the cells. On the front side of the display there are horizontal display electrodes that sit in between a magnesium-oxide (MgO) protective layer and an insulating dielectric layer. The MgO layer is in direct contact with the cells and the dielectric layer is in direct contact with the front glass plate. The horizontal and vertical electrodes form a grid from which each individual cell can be accessed. Each individual cell is walled off from surrounding cells so that activity in one cell does not affect another. The cell structure is similar to a honeycomb structure except with rectangular cells.

To illuminate a particular cell, the electrodes that intersect at the cell are charged by control circuitry and electric current flows through the cell, stimulating the gas (typically xenon and neon) atoms inside the cell. These ionized gas atoms, or plasmas, then release ultraviolet photons that interact with a phosphor material on the inside wall of the cell. The phosphor atoms are stimulated and electrons jump to higher energy levels. When these electrons return to their natural state, energy is released in the form of visible light. Every pixel on the display is made up of three subpixel cells. One subpixel cell is coated with red phosphor, another is coated with green phosphor, and the third cell is coated with blue phosphor. Light emitted from the subpixel cells is blended together to create an overall color for the pixel. The control circuitry can manipulate the intensity of light emitted from each cell, and therefore can produce a large gamut of colors. Light from each cell can be controlled and changed rapidly to produce a high-quality moving picture.

Projection television

A projection television uses a projector to create a small image from a video signal and magnify this image onto a viewable screen. The projector uses a bright beam of light and a lens system to project the image to a much larger size. A front-projection television uses a projector that is separate from the screen which could be a suitably prepared wall, and the projector is placed in front of the screen. The setup of a rear-projection television is similar to that of a traditional television in that the projector is contained inside the television box and projects the image from behind the screen.

Rear-projection television

The following are different types of rear-projection televisions, which differ based on the type of projector and how the image (before projection) is created:

• CRT rear-projection television: Small cathode ray tubes create the image in the same manner that a traditional CRT television does, which is by firing a beam of electrons onto a phosphor-coated screen; the image is projected onto a large screen. This is done to overcome the cathode ray tube size limit which is about 40 inches, the maximum size for a normal direct-view-CRT television set (see image). The projection cathode ray tubes can be arranged in various ways. One arrangement is to use one tube and three phosphor (red, green, blue) coatings. Alternatively, one black-and-white tube can be used with a spinning color wheel. A third option is to use three CRTs, one each for red, green, and blue.
• LCD rear-projection television: A lamp transmits light through a small LCD chip made up of individual pixels to create an image. The LCD projector uses dichroic mirrors to take the light and create three separate red, green, and blue beams, which are then passed through three separate LCD panels. The liquid crystals are manipulated using electric current to control the amount of light passing through. The lens system combines the three color images and projects them.
• DLP rear-projection television: A DLP projector creates an image using a digital micromirror device (DMD chip), which on its surface contains a large matrix of microscopic mirrors, each corresponding to one pixel (or sub-pixel) in an image. Each mirror can be tilted to reflect light such that the pixel appears bright, or the mirror can be tilted to direct light elsewhere (where it is absorbed) to make the pixel appear dark. Mirrors flip between light and dark positions, so subpixel brightness is controlled by proportionally varying the amount of time a mirror is in the bright position; its pulse-width modulation. The mirror is made of aluminum and is mounted on a torsion-supported yoke. There are electrodes on both sides of the yoke that control the tilt of the mirror using electrostatic attraction. The electrodes are connected to an SRAM cell located under each pixel, and charges from the SRAM cell move the mirrors. Color is created by a spinning color wheel (used with a single-chip projector) or a three-chip (red, green, blue) projector. The color wheel is placed between the lamp light source and the DMD chip such that the light passing through is colored and then reflected off the mirror array to determine brightness. A color wheel consists of a red, green, and blue sector, as well as a fourth sector to either control brightness or include a fourth color. This spinning color wheel in the single-chip arrangement can be replaced by red, green, and blue light-emitting diodes (LED). The three-chip projector uses a prism to split up the light into three beams (red, green, blue), each directed towards its own DMD chip. The outputs of the three DMD chips are recombined and then projected.

Laser Phosphor Display

In Laser Phosphor Display technology, first demonstrated in June 2010 at InfoComm, the image is provided by the use of lasers, which are located on the back of the television, reflected off a rapidly moving bank of mirrors to excite pixels on the television screen in a similar way to cathode ray tubes. The mirrors reflect the laser beams across the screen and so produce the necessary number of image lines. The small layers of phosphors inside the glass emit red, green or blue light when excited by a soft UV laser. The laser can be varied in intensity or completely turned on or off without a problem, which means that a dark display would need less power to project its images.

Comparison of television display technologies

CRT

Though large-screen CRT TVs/monitors exist, the screen size is limited by their impracticality. The bigger the screen, the greater the weight, and the deeper the CRT. A typical 32-inch television can weigh about 150 ⁠lb or more. The Sony PVM-4300 monitor weighed 440 ⁠lb (200kg) and had the largest ever CRT with a 43" diagonal display. SlimFit televisions exist, but are not common.

LCD

Advantages

• Slim profile
• Lighter and less bulky than rear-projection televisions
• Is less susceptible to burn-in: Burn-in refers to the television displaying a permanent ghost-like image due to constant, prolonged display of the image. Light-emitting phosphors lose their luminosity over time and, when frequently used, the low-luminosity areas become permanently visible.
• LCDs reflect very little light, allowing them to maintain contrast levels in well-lit rooms and not be affected by glare.
• Slightly lower power usage than equivalent sized Plasma displays.
• Can be wall-mounted.

Disadvantages

• Poor black level: Some light passes through even when liquid crystals completely untwist, so the best black color that can be achieved is varying shades of dark gray, resulting in worse contrast ratios and detail in the image. This can be mitigated by the use of a matrix of LEDs as the illuminator to provide nearly true black performance.
• Narrower viewing angles than competing technologies. It is nearly impossible to use an LCD without some image warping occurring.
• LCDs rely heavily on thin-film transistors, which can be damaged, resulting in a defective pixel.
• Typically have slower response times than Plasmas, which can cause ghosting and blurring during the display of fast-moving images. This is also improving by increasing the refresh rate of LCDs.

Plasma display

Advantages

• Slim cabinet profile
• Can be wall-mounted
• Lighter and less voluminous than rear-projection television sets
• More accurate color reproduction than that of an LCD; 68 billion (2³⁶) colors vs. 16.7 million (2²⁴) colors 
• Produces deep, true blacks, allowing for superior contrast ratios (+ 1:1,000,000)
• Wider viewing angles (+178°) than those of an LCD; the image does not degrade (dim and distort) when viewed from a high angle, as occurs with an LCD
• No motion blur; eliminated with higher refresh rates and faster response times (up to 1.0 microsecond), which make plasma TV technology ideal for viewing the fast-moving film and sport images

Disadvantages

• No longer being produced
• Susceptible to screen burn-in and image retention; late-model plasma TV sets feature corrective technology, such as pixel shifting
• Phosphor-luminosity diminishes over time, resulting in the gradual decline of absolute image-brightness; corrected with the 60,000-hour life-span of contemporary plasma TV technology (longer than that of CRT technology)
• Not manufactured in sizes smaller than 37-inches diagonal
• Susceptible to reflective glare in a brightly lighted room, which dims the image
• High rate of electrical power consumption
• Heavier than a comparable LCD TV set, because of the glass screen that contains the gases
• Costlier screen repair; the glass screen of a plasma TV set can be damaged permanently, and is more difficult to repair than the plastic screen of an LCD TV set

Projection television

Front-projection television

Advantages

• Significantly cheaper than flat-panel counterparts
• Front-projection picture quality approaches that of movie theater
• Front-projection televisions take up very little space because a projector screen is extremely slim, and even a suitably prepared wall can be used
• Display size can be extremely large, typically limited by room height.

Disadvantages

• Front-projection more difficult to set up because projector is separate and must be placed in front of the screen, typically on the ceiling
• Lamp may need to be replaced after heavy usage
• Image brightness is an issue, may require darkened room.

Rear-projection television

Advantages

• Significantly cheaper than flat-panel counterparts
• Projectors that are not phosphor-based (LCD/DLP) are not susceptible to burn-in
• Rear-projection is not subject to glare

Disadvantages

• Rear-projection televisions are much bulkier than flat-panel televisions
• Lamp may need to be replaced after heavy usage
• Rear-projection has smaller viewing angles than those of flat-panel displays

Comparison of different types of rear-projection televisions

CRT projector

Advantages:

• Achieves excellent black level and contrast ratio
• Achieves excellent color reproduction
• CRTs have generally very long lifetimes
• Greater viewing angles than those of LCDs

Disadvantages:

• Heavy and large, especially depth-wise
• If one CRT fails the other two should be replaced for optimal color and brightness balance
• Susceptible to burn-in because CRT is phosphor-based
• Needs to be "converged" (primary colors positioned so they overlay without color fringes) annually (or after set relocation)
• May display colour halos or lose focus

LCD projector

Advantages:

• Smaller than CRT projectors
• LCD chip can be easily repaired or replaced
• Is not susceptible to burn-in

Disadvantages:

• The Screen-door effect: Individual pixels may be visible on the large screen, giving the appearance that the viewer is looking through a screen door.
• Possibility of defective pixels
• Poor black level: Some light passes through even when liquid crystals completely untwist, so the best black color that can be achieved is a very dark gray, resulting in worse contrast ratios and detail in the image. Some newer models use an adjustable iris to help offset this.
• Not as slim as DLP projection television
• Uses lamps for light, lamps may need to be replaced
• Fixed number of pixels, other resolutions need to be scaled to fit this
• Limited viewing angles

DLP projector

Advantages:

• Slimmest of all types of projection televisions
• Achieves excellent black level and contrast ratio
• DMD chip can be easily repaired or replaced
• Is not susceptible to burn-in
• Better viewing angles than those of CRT projectors
• Image brightness only decreases due to the age of the lamp
• defective pixels are rare
• Does not experience the screen-door effect

Disadvantages:

• Uses lamps for light, lamps need to be replaced on average once every year and a half to two years. Current models with LED lamps reduce or eliminate this. Estimated lifetime of LED lamps is over 100,000 hours.
• Fixed number of pixels, other resolutions need to be scaled to fit this. This is a limitation only when compared with CRT displays.
• The Rainbow Effect: This is an unwanted visual artifact that is described as flashes of colored light seen when the viewer looks across the display from one side to the other. This artifact is unique to single-chip DLP projectors. The Rainbow Effect is significant only in DLP displays that use a single white lamp with a "color wheel" that is synchronized with the display of red, green and blue components. LED illumination systems that use discrete red, green and blue LEDs in concert with the display of red, green and blue components at high frequency reduce, or altogether eliminate, the Rainbow effect.

Flat-panel display

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Flat-panel_display 

 

A flat-panel display (FPD) is an electronic viewing device used to enable people to see content (still images, moving images, text, or other visual material) in a range of entertainment, consumer electronics, personal computer, and mobile devices, and many types of medical, transportation and industrial equipment. They are far lighter and thinner than traditional cathode ray tube (CRT) television sets and are usually less than 10 centimetres (3.9 in) thick. Flat-panel displays can be divided into two display device categories: volatile and static. Volatile displays require that pixels be periodically electronically refreshed to retain their state (e.g. liquid-crystal displays (LCD)). A volatile display only shows an image when it has battery or AC mains power. Static flat-panel displays rely on materials whose color states are bistable (e.g., e-book reader tablets from Sony), and as such, flat-panel displays retain the text or images on the screen even when the power is off. As of 2016, flat-panel displays have almost completely replaced old CRT displays. In many 2010-era applications, specifically small portable devices such as laptops, mobile phones, smartphones, digital cameras, camcorders, point-and-shoot cameras, and pocket video cameras, any display disadvantages of flat-panels (as compared with CRTs) are made up for by portability advantages (low power consumption from batteries, thinness and lightweightness).

Most 2010s-era flat-panel displays use LCD and/or light emitting diode (LED) technologies. Most LCD screens are back-lit as color filters are used to display colors. Flat-panel displays are thin, lightweight, provide better linearity and are capable of higher resolution than typical consumer-grade TVs from earlier eras. The highest resolution for consumer-grade CRT TVs was 1080i; in contrast, many flat-panels can display 1080p or even 4K resolution. As of 2016, some devices that use flat-panels, such as tablet computers, smartphones and, less commonly, laptops, use touchscreens, a feature that enables users to select onscreen icons or trigger actions (e.g., playing a digital video) by touching the screen. Many touchscreen-enabled devices can display a virtual QWERTY or numeric keyboard on the screen, to enable the user to type words or numbers.

A multifunctional monitor (MFM) is a flat-panel display that has additional video inputs (more than a typical LCD monitor) and is designed to be used with a variety of external video sources, such as VGA input, HDMI input from a VHS VCR or video game console and, in some cases, a USB input or card reader for viewing digital photos. In many instances, an MFM also includes a TV tuner, making it similar to a LCD TV that offers computer connectivity.

History

The first engineering proposal for a flat-panel TV was by General Electric in 1954 as a result of its work on radar monitors. The publication of their findings gave all the basics of future flat-panel TVs and monitors. But GE did not continue with the R&D required and never built a working flat panel at that time. The first production flat-panel display was the Aiken tube, developed in the early 1950s and produced in limited numbers in 1958. This saw some use in military systems as a heads up display and as an oscilloscope monitor, but conventional technologies overtook its development. Attempts to commercialize the system for home television use ran into continued problems and the system was never released commercially.

The Philco Predicta featured a relatively flat (for its day) cathode ray tube setup and would be the first commercially released "flat panel" upon its launch in 1958; the Predicta was a commercial failure. The plasma display panel was invented in 1964 at the University of Illinois, according to The History of Plasma Display Panels.

LCD displays

The MOSFET (metal-oxide-semiconductor field-effect transistor, or MOS transistor) was invented by Mohamed M. Atalla and Dawon Kahng at Bell Labs in 1959, and presented in 1960. Building on their work, Paul K. Weimer at RCA developed the thin-film transistor (TFT) in 1962. It was a type of MOSFET distinct from the standard bulk MOSFET. The idea of a TFT-based LCD was conceived by Bernard J. Lechner of RCA Laboratories in 1968. B.J. Lechner, F.J. Marlowe, E.O. Nester and J. Tults demonstrated the concept in 1968 with a dynamic scattering LCD that used standard discrete MOSFETs.

The first active-matrix addressed electroluminescent display (ELD) was made using TFTs by T. Peter Brody's Thin-Film Devices department at Westinghouse Electric Corporation in 1968. In 1973, Brody, J. A. Asars and G. D. Dixon at Westinghouse Research Laboratories demonstrated the first 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 TFTs in 1974.

By 1982, pocket LCD TVs based on LCD technology were developed in Japan. The 2.1-inch Epson ET-10 Epson Elf was the first color LCD pocket TV, released in 1984. In 1988, a Sharp research team led by engineer T. Nagayasu demonstrated a 14-inch full-color LCD display, which convinced the electronics industry that LCD would eventually replace CRTs as the standard television display technology. As of 2013, all modern high-resolution and high-quality electronic visual display devices use TFT-based active-matrix displays.

LED displays

The first usable LED display was developed by Hewlett-Packard (HP) and introduced in 1968. It was the result of research and development (R&D) on practical LED technology between 1962 and 1968, by a research team under Howard C. Borden, Gerald P. Pighini, and Mohamed M. Atalla, at HP Associates and HP Labs. In February 1969, they introduced the HP Model 5082-7000 Numeric Indicator. It was the first alphanumeric LED display, and was a revolution in digital display technology, replacing the Nixie tube for numeric displays and becoming the basis for later LED displays. In 1977, James P Mitchell prototyped and later demonstrated what was perhaps the earliest monochromatic flat panel LED television display. 

Ching W. Tang and Steven Van Slyke at Eastman Kodak built the first practical organic LED (OLED) device in 1987. In 2003, Hynix produced an organic EL driver capable of lighting in 4,096 colors. In 2004, the Sony Qualia 005 was the first LED-backlit LCD display.^[25] The Sony XEL-1, released in 2007, was the first OLED television.

Common types

Liquid crystal display (LCD)

An LCD screen used as an information display for travellers.

LCDs are lightweight, compact, portable, cheap, more reliable, and easier on the eyes than CRT screens. LCD screens use a thin layer of liquid crystal, a liquid that exhibits crystalline properties. It is sandwiched between two electrically conducting plates. The top plate has transparent electrodes deposited on it, and the back plate is either fitted with a reflector or is illuminated from behind so that the viewer can see the images on the screen. By applying controlled electrical signals across the plates, various segments of the liquid crystal can be activated, causing changes in their light diffusing or polarizing properties. These segments can either transmit or block light. An image is produced by passing light through selected segments of the liquid crystal to the viewer. They are used in various electronics like watches, calculators, and notebook computers.

LCD with backlit light-emitting diode (LED)

Some LCD screens are back-lit with a number of LEDs. LEDs are two-lead semiconductor light sources. The image is still generated by the LCD. LED-backlit LCD displays are the most prevalent in the 2010s.

Plasma panel

A plasma display consists of two glass plates separated by a thin gap filled with a gas such as neon. Each of these plates has several parallel electrodes running across it. The electrodes on the two plates are at right angles to each other. A voltage applied between the two electrodes one on each plate causes a small segment of gas at the two electrodes to glow. The glow of gas segments is maintained by a lower voltage that is continuously applied to all electrodes. By 2010, consumer plasma displays had been discontinued by numerous manufacturers.

Electroluminescent panel

In an electroluminescent display (ELD), the image is created by applying electrical signals to the plates which makes the phosphor glow.

Organic light-emitting diode

An OLED (organic light-emitting diode) is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound which emits light in response to an electric current. This layer of organic semiconductor is situated between two electrodes; typically, at least one of these electrodes is transparent. OLEDs are used to create digital displays in devices such as television screens, computer monitors, portable systems such as mobile phones, handheld game consoles and PDAs.

Quantum dot light emitting diode

QLED or quantum dot LED is a flat panel display technology introduced by Samsung under this trademark. Other television set manufacturers such as Sony have used the same technology to enhance the backlighting of LCD TVs already in 2013.  Quantum dots create their own unique light when illuminated by a light source of shorter wavelength such as blue LEDs. This type of LED TV enhances the color gamut of LCD panels, where the image is still generated by the LCD. In the view of Samsung, quantum dot displays for large-screen TVs are expected to become more popular than the OLED displays in the coming years; Firms like Nanoco and Nanosys compete to provide the QD materials. In the meantime, Samsung Galaxy devices such as smartphones are still equipped with OLED displays manufactured by Samsung as well. Samsung explain on their website that the QLED TV they produce can determine what part of the display needs more or less contrast. Samsung also announced a partnership with Microsoft that will promote the new Samsung QLED TV.

Volatile

A large LED display at the Taipei Arena displays commercials and movie trailers.

Volatile displays require that pixels be periodically refreshed to retain their state, even for a static image. As such, a volatile screen needs electrical power, either from mains electricity (being plugged into a wall socket) or a battery to maintain an image on the display or change the image. This refresh typically occurs many times a second. If this is not done, for example, if there is a power outage, the pixels will gradually lose their coherent state, and the image will "fade" from the screen.

Examples

The following flat-display technologies have been commercialized in 1990s to 2010s:

• Plasma display panel (PDP)
• Active-matrix liquid-crystal display (AMLCD)
• Rear projection: Digital Light Processing (DLP), LCD, LCOS
• Electronic paper: E Ink, Gyricon
• Light-emitting diode display (LED)
• Active-matrix organic light-emitting diode (AMOLED)
• Quantum dot display (QLED)

Technologies that were extensively researched, but their commercialization was limited or has been ultimately abandoned:

• Active-matrix electroluminescent display (ELD)
• Interferometric modulator display (IMOD)
• Field emission display (FED)
• Surface-conduction electron-emitter display (SED, SED-TV)

Static

Amazon's Kindle Keyboard e-reader displaying a page of an e-book. The Kindle's image of the book's text will remain onscreen even if the battery runs out, as it is a static screen technology. Without power, however, the user cannot change to a new page.

 

Static flat-panel displays rely on materials whose color states are bistable. This means that the image they hold requires no energy to maintain, but instead requires energy to change. This results in a much more energy-efficient display, but with a tendency toward slow refresh rates which are undesirable in an interactive display. Bistable flat-panel displays are beginning deployment in limited applications (cholesteric liquid crystal displays, manufactured by Magink, in outdoor advertising; electrophoretic displays in e-book reader devices from Sony and iRex; anlabels; interferometric modulator displays in a smartwatch).

Television show

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Television_show 

A live television show set and cameras

A television show (often simply TV show) is any content produced for viewing on a television set and broadcast via over-the-air, satellite, cable, - excluding breaking news, advertisements, or trailers that are typically placed between shows. Television shows are most often scheduled for broadcast well ahead of time and appear on electronic guides or other TV listings, but streaming services often make them available for viewing anytime.

A television show is also called a television program (British English: programme), especially if it lacks a narrative structure. A television series is usually released in episodes that follow a narrative, and are usually divided into seasons (US and Canada) or series (UK) – yearly or semiannual sets of new episodes. A show with a limited number of episodes may be called a miniseries, serial, or limited series. A one-time show may be called a "special". A television film ("made-for-TV movie" or "television movie") is a film that is initially broadcast on television rather than released in theaters or direct-to-video. 

Television shows can be viewed as they are broadcast in real time (live), be recorded on home video or a digital video recorder for later viewing, or be viewed on demand via a set-top box or streamed over the internet.

History

The first television shows were experimental, sporadic broadcasts viewable only within a very short range from the broadcast tower starting in the 1930s. Televised events such as the 1936 Summer Olympics in Germany, the 1937 coronation of King George VI in the UK, and David Sarnoff's famous introduction at the 1939 New York World's Fair in the US spurred a growth in the medium, but World War II put a halt to development until after the war. The 1947 World Series inspired many Americans to buy their first television set and then in 1948, the popular radio show Texaco Star Theater made the move and became the first weekly televised variety show, earning host Milton Berle the name "Mr Television" and demonstrating that the medium was a stable, modern form of entertainment which could attract advertisers. The first national live television broadcast in the US took place on September 4, 1951 when President Harry Truman's speech at the Japanese Peace Treaty Conference in San Francisco was transmitted over AT&T's transcontinental cable and microwave radio relay system to broadcast stations in local markets.

The first national color broadcast (the 1954 Tournament of Roses Parade) in the US occurred on January 1, 1954. During the following ten years most network broadcasts, and nearly all local programming, continued to be in black-and-white. A color transition was announced for the fall of 1965, during which over half of all network prime-time programming would be broadcast in color. The first all-color prime-time season came just one year later. In 1972, the last holdout among daytime network shows converted to color, resulting in the first completely all-color network season.

Formats and genres

Television shows are more varied than most other forms of media due to the wide variety of formats and genres that can be presented. A show may be fictional (as in comedies and dramas), or non-fictional (as in documentary, news, and reality television). It may be topical (as in the case of a local newscast and some made-for-television films), or historical (as in the case of many documentaries and fictional series). They could be primarily instructional or educational, or entertaining as is the case in situation comedy and game shows.

A drama program usually features a set of actors playing characters in a historical or contemporary setting. The program follows their lives and adventures. Before the 1980s, shows (except for soap opera-type serials) typically remained static without story arcs, and the main characters and premise changed little.^{[citation needed]} If some change happened to the characters' lives during the episode, it was usually undone by the end. Because of this, the episodes could be broadcast in any order.^{[citation needed]} Since the 1980s, many series feature progressive change in the plot, the characters, or both. For instance, Hill Street Blues and St. Elsewhere were two of the first American prime time drama television series to have this kind of dramatic structure while the later series Babylon 5 further exemplifies such structure in that it had a predetermined story running over its intended five-season run. In 2012, it was reported that television was growing into a larger component of major media companies' revenues than film. Some also noted the increase in quality of some television programs. In 2012, Academy-Award-winning film director Steven Soderbergh, commenting on ambiguity and complexity of character and narrative, stated: "I think those qualities are now being seen on television and that people who want to see stories that have those kinds of qualities are watching television."

Production

Development

United States

When a person or company decides to create a new series, they develop the show's elements, consisting of the concept, the characters, the crew, and cast. Then they often "pitch" it to the various networks in an attempt to find one interested enough to order a prototype first episode of the series, known as a pilot. Eric Coleman, an animation executive at Disney, told an interviewer, "One misconception is that it's very difficult to get in and pitch your show, when the truth is that development executives at networks want very much to hear ideas. They want very much to get the word out on what types of shows they're looking for."

To create the pilot, the structure and team of the whole series must be put together. If audiences respond well to the pilot, the network will pick up the show to air it the next season (usually Fall). Sometimes they save it for mid-season, or request rewrites and additional review (known in the industry as development hell). Other times, they pass entirely, forcing the show's creator to "shop it around" to other networks. Many shows never make it past the pilot stage.

The show hires a stable of writers, who usually work in parallel: the first writer works on the first episode, the second on the second episode, etc. When all the writers have been used, episode assignment starts again with the first writer. On other shows, however, the writers work as a team. Sometimes they develop story ideas individually, and pitch them to the show's creator, who folds them together into a script and rewrites them.

If the show is picked up, the network orders a "run" of episodes—usually only six or 13 episodes at first, though a season typically consists of at least 22 episodes. The midseason seven and last nine episodes are sometimes called the "mid-seven" and "back nine"—borrowing the colloquial terms from bowling and golf.

United Kingdom

The method of "team writing" is employed on some longer dramatic series (usually running up to a maximum of around 13 episodes). The idea for such a program may be generated "in-house" by one of the networks; it could originate from an independent production company (sometimes a product of both). For example, the BBC's long-running soap opera EastEnders is wholly a BBC production, whereas its popular drama Life on Mars was developed by Kudos in association with the broadcaster.

There are still a significant number of programs (usually sitcoms), however, that are built by just one or two writers and a small, close-knit production team. These are "pitched" in the traditional way, but since the creators handle all the writing requirements, there is a run of six or seven episodes per series once approval has been given. Many of the most popular British comedies have been made this way, including Monty Python's Flying Circus (albeit with an exclusive team of six writer-performers), Fawlty Towers, Blackadder and The Office.

Other nations

The production company is often separate from the broadcaster. The executive producer, often the show's creator, is in charge of running the show. They pick the crew and help cast the actors, approve and sometimes write series plots—some even write or direct major episodes—while various other producers help to ensure that the show runs smoothly. Very occasionally, the executive producer will cast themselves in the show. As with filmmaking or other electronic media production, producing of an individual episode can be divided into three parts: pre-production, principal photography, and post-production.

Estonia also has television and it has been active for many years as seen by all the years in estonian television: https://en.wikipedia.org/wiki/List_of_years_in_Estonian_television

Pre-production

Arthur Schlesinger Jr.

Pre-production begins when a script is approved. A director is chosen to plan the episode's final look.

Pre-production tasks include storyboarding; construction of sets, props, and costumes; casting guest stars; budgeting; acquiring resources like lighting, special effects, stunts, etc. Once the show is planned, it must then be scheduled: scenes are often filmed out of sequence, guest actors or even regulars may only be available at certain times. Sometimes the principal photography of different episodes must be done at the same time, complicating the schedule (a guest star might shoot scenes from two episodes on the same afternoon). Complex scenes are translated from storyboard to animatics to further clarify the action. Scripts are adjusted to meet altering requirements.

Some shows have a small stable of directors, but also usually rely on outside directors. Given the time constraints of broadcasting, a single show might have two or three episodes in pre-production, one or two episodes in principal photography, and a few more in various stages of post-production. The task of directing is complex enough that a single director can usually not work on more than one episode or show at a time, hence the need for multiple directors.

Principal photography

Principal photography is the actual filming of the episode. Director, actors and crew gather at a television studio or on location for filming or videoing a scene. A scene is further divided into shots, which should be planned during pre-production. Depending on scheduling, a scene may be shot in non-sequential order of the story. Conversations may be filmed twice from different camera angles, often using stand-ins, so one actor might perform all their lines in one set of shots, and then the other side of the conversation is filmed from the opposite perspective. To complete a production on time, a second unit may be filming a different scene on another set or location at the same time, using a different set of actors, an assistant director, and a second unit crew. A director of photography supervises the lighting of each shot to ensure consistency.

Live events are usually covered by Outside Broadcast crews using mobile television studios, known as scanners or OB trucks. Although varying greatly depending on the era and subject covered, these trucks were normally crewed by up to 15 skilled operators and production personnel. In the UK for most of the 20th century, the BBC was the preeminent provider of outside broadcast coverage. BBC crews worked on almost every major event, including Royal weddings and funerals, major political and sporting events, and even drama programmes.

Post-production

Once principal photography is complete, producers coordinate tasks to begin the video editing. Visual and digital video effects are added to the film; this is often outsourced to companies specializing in these areas. Often music is performed with the conductor using the film as a time reference (other musical elements may be previously recorded). An editor cuts the various pieces of film together, adds the musical score and effects, determines scene transitions, and assembles the completed show.

Budgets and revenues

Most television networks throughout the world are 'commercial', dependent on selling advertising time or acquiring sponsors. Broadcasting executives' main concern over their programming is on audience size. Once the number of 'free to air' stations was restricted by the availability of channel frequencies, but cable TV (outside the United States, satellite television) technology has allowed an expansion in the number of channels available to viewers (sometimes at premium rates) in a much more competitive environment.

In the United States, the average broadcast network drama costs $3 million an episode to produce, while cable dramas cost $2 million on average. The pilot episode may be more expensive than a regular episode. In 2004, Lost's two-hour pilot cost $10 to $14 million, in 2008 Fringe's two-hour pilot cost $10 million, and in 2010, Boardwalk Empire was $18 million for the first episode. In 2011, Game of Thrones was $5 to $10 million, Pan Am cost an estimated $10 million, while Terra Nova's two-hour pilot was between $10 to $20 million.

Many scripted network television shows in the United States are financed through deficit financing: a studio finances the production cost of a show and a network pays a license fee to the studio for the right to air the show. This license fee does not cover the show's production costs, leading to the deficit. Although the studio does not make its money back in the original airing of the show, it retains ownership of the show. This ownership retention allows the studio to make its money back and earn a profit through syndication and sales of DVDs and Blu-rays. This system places most of the financial risk on the studios, however a show that is a hit in the syndication and home video markets can more than make up for the misses. Although the deficit financing system places minimal financial risk on the networks, they lose out on the future profits of big hits since they are only licensing the shows.

Costs are recouped mainly by advertising revenues for broadcast networks and some cable channels, while other cable channels depend on subscription revenues. In general, advertisers, and consequently networks that depend on advertising revenues, are more interested in the number of viewers within the 18–49 age range than the total number of viewers. Advertisers are willing to pay more to advertise on shows successful with young adults because they watch less television and are harder to reach than older adults. According to Advertising Age, during the 2007–08 season, Grey's Anatomy was able to charge $419,000 per commercial, compared to only $248,000 for a commercial during CSI, despite CSI having almost five million more viewers on average. Due to its strength in young demos, Friends was able to charge almost three times as much for a commercial as Murder, She Wrote, even though the two series had similar total viewer numbers during the seasons they were on the air together. Glee and The Office drew fewer total viewers than NCIS during the 2009–10 season, but earned an average of $272,694 and $213,617 respectively, compared to $150,708 for NCIS.

Distribution

After production, the show is handed over to the television network, which sends it out to its affiliate stations, which broadcast it in the specified broadcast programming time slot. If the Nielsen ratings are good, the show is kept alive as long as possible. If not, the show is usually canceled. The show's creators are then left to shop around remaining episodes, and the possibility of future episodes, to other networks. On especially successful series, the producers sometimes call a halt to a series on their own like Seinfeld, The Cosby Show, Corner Gas, and M*A*S*H and end it with a concluding episode, which sometimes is a big series finale.

On rare occasions, a series that has not attracted particularly high ratings and has been canceled can be given a reprieve if home video viewership has been particularly strong. This has happened in the cases of Family Guy in the US and Peep Show in the UK.

In the United States, if the show is popular or lucrative, and a minimum number of episodes (usually 100) have been made, it can go into broadcast syndication, where rights to broadcast the program are then resold for cash or put into a barter exchange (offered to an outlet for free in exchange for airing additional commercials elsewhere in the station's broadcast day).

Seasons/series

The terminology used to define a set of episodes produced by a television series varies from country to country.

North American usage

In North American television, a series is a connected set of television program episodes that run under the same title, possibly spanning many seasons. Since the late 1960s, this broadcast programming schedule typically includes between 20 and 26 episodes. Before then, a regular television season could average at least 30 episodes, and some TV series may have had as many as 39 episodes in a season.

Until the 1980s, most (but certainly not all) new programs for the American broadcast networks debuted in the "fall season", which ran from September through March and nominally contained from 24 to 26 episodes. These episodes were rebroadcast during the spring (or summer) season, from April through August. Because of cable television and the Nielsen sweeps, the "fall" season now normally extends to May. Thus, a "full season" on a broadcast network now usually runs from September through May for at least 22 episodes.

A full season is sometimes split into two separate units with a hiatus around the end of the calendar year, such as the first season of Jericho on CBS. When this split occurs, the last half of the episodes sometimes are referred to with the letter B as in "The last nine episodes (of The Sopranos) will be part of what is being called either "Season 6, Part 2" or "Season 6B", or in "Futurama is splitting its seasons similar to how South Park does, doing half a season at a time, so this is season 6B for them." Since the 1990s, these shorter seasons also have been referred to as ".5" or half seasons, where the run of shows between September and December is labeled "Season X", and the second run between January and May labeled "Season X.5". Examples of this include the 2004 incarnation of Battlestar Galactica, ABC's FlashForward, Fox Kids's Rhino Man: The Series and ABC Family's Make It or Break It. 

Since at least the 2000s, new broadcast television series are often ordered (funded) for just the first 10 to 13 episodes, to gauge audience interest. If a series is popular, the network places a "back nine order" and the season is completed to the regular 20 to 26 episodes. An established series which is already popular, however, will typically receive an immediate full-season order at the outset of the season. A midseason replacement is a less-expensive short-run show of generally 10 to 13 episodes designed to take the place of an original series that failed to garner an audience and has not been picked up. A "series finale" is the last show of the series before the show is no longer produced. (In the UK, it means the end of a season, what is known in the United States as a "season finale").

A standard television season in the United States runs predominantly across the fall and winter, from late September to May. During the summer months of June through roughly mid-September, network schedules typically feature reruns of their flagship programs, first-run series with lower ratings expectations, and other specials. First-run scripted series are typically shorter and of a lower profile than those aired during the main season and can also include limited series events. Reality and game shows have also been a fixture of the schedule.

In Canada, the commercial networks air most US programming in tandem with the US television season, but their original Canadian shows follow a model closer to British than American television production. Due to the smaller production budgets available in Canada, a Canadian show's season normally runs to a maximum of 13 episodes rather than 20 or more, although an exceptionally popular series such as Corner Gas or Murdoch Mysteries might receive 20-episode orders in later seasons. Canadian shows do not normally receive "back nine" extensions within the same season, however; even a popular series simply ends for the year when the original production order has finished airing, and an expanded order of more than 13 episodes is applied to the next season's renewal order rather than an extension of the current season. Only the public CBC Television normally schedules Canadian-produced programming throughout the year; the commercial networks typically now avoid scheduling Canadian productions to air in the fall, as such shows commonly get lost amid the publicity onslaught of the US fall season. Instead, Canadian-produced shows on the commercial networks typically air either in the winter as mid-season replacements for cancelled US shows or in the summer (which may also improve their chances of being picked up by a US network for a summer run).

Miniseries, limited series, and event series

While network orders for 13- or 22-episode seasons are still pervasive in the television industry, several shows have deviated from this traditional trend. Written to be closed-ended and of shorter length than other shows, they are marketed with a variety of terms.

• Miniseries: a very short, closed-ended series, typically six or more hours in two or more parts (nights), similar to an extended television movie. Many early miniseries were adaptations of popular novels of the day, such as The National Dream (1974), Roots (1977), and North and South (1985). In recent years, as described by several television executives interviewed by The Hollywood Reporter, the term miniseries has grown to have negative connotations within the industry, having become associated with melodrama-heavy works that were commonly produced under the format, while limited series or event series receive higher respect.

• Limited series: distinct from miniseries in that the production is seen to have potential to be renewed, but without the requirement of it having as many episodes as a typical order per season. Under the Dome, Killer Women, and Luther were marketed as limited series. Individual season-length stories of anthology series such as American Horror Story, Fargo, and True Detective are also described as "limited series". The Primetime Emmys have had to make numerous changes to their miniseries/limited series category to accommodate anthology and other limited series.
• Event series: largely considered a marketing term, falling under the general category of event television. The term can be applied to almost any new, short-run series, such as 24: Live Another Day. It has also been used to describe game shows like The Million Second Quiz which aired for just two weeks.

India

In India, the shows are particularly referred to as serials, wherein the production is complex as well. The shows usually amount to at least 200 episodes, of 20 to 25 minutes each. On special episodes, referred to as Maha-Episodes, the duration last up to about 45 to 50 minutes. The show airs till the TRP (television rating point) is a little less than decent. The rating points depend on various criteria. Usually, shows which fail to attract TRP for a long time are shut down.

UK, Ireland and Australia usage

In the United Kingdom and other countries, these sets of episodes are referred to as a "series". In Australia, the broadcasting may be different from North American usage. The terms series and season are both used and are the same. For example, Battlestar Galactica has an original series as well as a remake, both are considered a different series each with their own number of individual seasons. 

Australian television does not follow "seasons" in the way that US television does; for example, there is no "fall season" or "fall schedule". For many years, popular night-time dramas in Australia would run for much of the year, and would only go into recess during the summer period (December to February, as Australia is in the Southern Hemisphere), when ratings are not taken. Therefore, popular dramas would usually run from February through November each year. This schedule was used in the 1970s for popular dramas including Number 96. Many drama series, such as McLeod's Daughters, have received between 22 and 32 episodes per season. Typically, soap operas, which have always run in season format in Australia, such as Home and Away, would usually begin a new season in late January, while the season finale would air in late November, as the show is off air for two months, or sometimes longer, depending on the schedule. In recent years, a new season would begin in early February, and the season finale would broadcast in early December. Since Home and Away's inception, it normally receives 230 episodes per season. Some seasons have seen between 205 and 235 episodes commissioned. During the Olympics, Home and Away would often go on hiatus, which was referred to as an "Olympic cliffhanger". Therefore, the number of episodes would decrease. Australian situation comedy series' seasons are approximately 13 episodes long and premiere any time between February and November. 

British shows have tended toward shorter series in recent years. For example, the first series of long-running science fiction show Doctor Who in 1963 featured forty-two 25‑minute episodes, this dropped to twenty-five by 1970 to accommodate changes in production and continued to 1984. For 1985 fewer but longer episodes were shown, but even after a return to shorter episodes in 1986, lack of support within the BBC meant fewer episodes were commissioned leading to only fourteen 25‑minute episodes up to those in 1989 after which it was cancelled. The revival of Doctor Who from 2005 has comprised thirteen 45‑minute installments. There are some series in the UK that have a larger number of episodes, for example Waterloo Road started with 8 to 12 episodes, but from series three onward it increased to twenty episodes and series seven will contain 30 episodes. Recently, American non-cable networks have also begun to experiment with shorter series for some programs, particularly reality shows, such as Survivor. They often air two series per year, resulting in roughly the same number of episodes per year as a drama.

This is a reduction from the 1950s, in which many American shows (e.g. Gunsmoke) had between 29 and 39 episodes per season. Actual storytelling time within a commercial television hour has also gradually reduced over the years, from 50 minutes out of every 60 to the current 44 (and even less on some networks), beginning in the early 21st century.

The usage of "season" and "series" differ for DVD and Blu-ray releases in both Australia and the UK. In Australia, many locally produced shows are termed differently on home video releases. For example, a set of the television drama series Packed to the Rafters or Wentworth is referred to as "season" ("The Complete First Season", etc.), whereas drama series such as Tangle are known as a "series" ("Series 1", etc.). British-produced shows such as Mrs. Brown's Boys are referred to as "season" in Australia for the DVD and Blu-ray releases.

In the UK and Ireland, most programmes are referred to as 'series' while 'season' is starting to be used for some American and international releases.

Running time

In the United States, dramas produced for hour-long time slots typically are 39 to 42 minutes in length (excluding advertisements), while sitcoms produced for 30-minute time slots typically are 18 to 21 minutes long. There are exceptions: subscription-based TV channels, such as HBO, Starz, Cinemax, and Showtime, have episodes that are 45 to 48 minutes long, similar to Britain. 

In Britain dramas typically run from 46 to 48 minutes on commercial channels, and 57 to 59 minutes on the BBC. Half-hour programs are around 22 minutes on commercial channels and around 28 minutes on the BBC. The longer duration on the BBC is due to the lack of advertising breaks.

In France most television shows (whether dramas, game shows or documentaries) have a duration of 52 minutes. This is the same on nearly all French networks (TF1, France 2, France 5, M6, Canal+, etc.).