A three-CCD (3CCD) camera is a camera whose imaging system uses three separate charge-coupled devices (CCDs), each one receiving filtered red, green, or blue color ranges. Light coming in from the lens is split by a beam-splitter prism into three beams, which are then filtered to produce colored light in three color ranges or "bands". The system is employed by high quality still cameras, telecine systems, professional video cameras and some prosumer video cameras.
Compared to cameras with only one CCD, three-CCD cameras generally provide superior image quality by using full-frame dichroic filters to better separate the red, green and blue color bands, and better low-light performance. By separating red, green, and blue color ranges with a 1:1 pixel ratio (known as "4:4:4"), three-CCD cameras achieve much better precision than single-CCD cameras.
In contrast, almost all single-CCD cameras use a Bayer filter, using less accurate dye filters in front of each pixel to separate the colors. Because each pixel on a single CCD sensor is covered with its own tiny color filter, a frame is necessary to keep the dye filters from leaking into adjacent pixels. The result is less light absorbed compared to a CCD without a Bayer filter. Typically there is a 2:1 ratio of green and red/blue pixels, producing less color detail.
A charge-coupled device (CCD) is an integrated circuit containing an array of linked, or coupled, capacitors. Under the control of an external circuit, each capacitor can transfer its electric charge to a neighboring capacitor. CCD sensors are a major technology used in digital imaging.
In digital imaging, a pixel, pel, or picture element is the smallest addressable element in a raster image, or the smallest addressable element in an all points addressable display device; so it is the smallest controllable element of a picture represented on the screen.
The RGB color model is an additive color model in which the red, green, and blue primary colors of light are added together in various ways to reproduce a broad array of colors. The name of the model comes from the initials of the three additive primary colors, red, green, and blue.
A digital camera is a camera that captures photographs in digital memory. Most cameras produced today are digital, largely replacing those that capture images on photographic film. Digital cameras are now widely incorporated into mobile devices like smartphones with the same or more capabilities and features of dedicated cameras. While there are still dedicated digital cameras, many more cameras are now incorporated into mobile devices like smartphones. High-end, high-definition dedicated cameras are still commonly used by professionals and those who desire to take higher-quality photographs.
Telecine is the process of transferring film into video and is performed in a color suite. The term is also used to refer to the equipment used in the post-production process. Telecine enables a motion picture, captured originally on film stock, to be viewed with standard video equipment, such as television sets, video cassette recorders (VCR), DVD, Blu-ray Disc or computers. Initially, this allowed television broadcasters to produce programmes using film, usually 16mm stock, but transmit them in the same format, and quality, as other forms of television production. Furthermore, telecine allows film producers, television producers and film distributors working in the film industry to release their productions on video and allows producers to use video production equipment to complete their filmmaking projects. Within the film industry, it is also referred to as a TK, because TC is already used to designate timecode. Motion picture film scanners are similar to telecines.
LBCAST is a type of photo sensor which the manufacturer claims is simpler and thus smaller and faster than CMOS sensors. It was developed over ten years by Nikon, in parallel with other manufacturer's development of CMOS, and resulted in shipping product in 2003.
Color photography is photography that uses media capable of capturing and reproducing colors. By contrast, black-and-white or gray-monochrome photography records only a single channel of luminance (brightness) and uses media capable only of showing shades of gray.
A professional video camera is a high-end device for creating electronic moving images. Originally developed for use in television studios or with outside broadcast trucks, they are now also used for music videos, direct-to-video movies, corporate and educational videos, wedding videos, among other uses. Since the 2000s, most professional video cameras are digital professional video cameras.
The Foveon X3 sensor is a digital camera image sensor designed by Foveon, Inc., and manufactured by Dongbu Electronics. It uses an array of photosites that consist of three vertically stacked photodiodes. Each of the three stacked photodiodes has a different spectral sensitivity, allowing it to respond differently to different wavelengths. The signals from the three photodiodes are then processed as additive color data that are transformed to a standard RGB color space.
A Bayer filter mosaic is a color filter array (CFA) for arranging RGB color filters on a square grid of photosensors. Its particular arrangement of color filters is used in most single-chip digital image sensors used in digital cameras, camcorders, and scanners to create a color image. The filter pattern is half green, one quarter red and one quarter blue, hence is also called BGGR,RGBG, GRBG, or RGGB.
A dichroic prism is a prism that splits light into two beams of differing wavelength (colour). A trichroic prism assembly combines two dichroic prisms to split an image into 3 colours, typically as red, green and blue of the RGB colour model. They are usually constructed of one or more glass prisms with dichroic optical coatings that selectively reflect or transmit light depending on the light's wavelength. That is, certain surfaces within the prism act as dichroic filters. These are used as beam splitters in many optical instruments.
A digital camera back is a device that attaches to the back of a camera in place of the traditional negative film holder and contains an electronic image sensor. This lets cameras that were designed to use film take digital photographs. These camera backs are generally expensive by consumer standards and are primarily built to be attached on medium- and large-format cameras used by professional photographers.
Image noise is random variation of brightness or color information in images, and is usually an aspect of electronic noise. It can be produced by the image sensor and circuitry of a scanner or digital camera. Image noise can also originate in film grain and in the unavoidable shot noise of an ideal photon detector. Image noise is an undesirable by-product of image capture that obscures the desired information.
A demosaicing algorithm is a digital image process used to reconstruct a full color image from the incomplete color samples output from an image sensor overlaid with a color filter array (CFA). It is also known as CFA interpolation or color reconstruction.
Digital photography uses cameras containing arrays of electronic photodetectors interfaced to an analog-to-digital converter (ADC) to produce images focused by a lens, as opposed to an exposure on photographic film. The digitized image is stored as a computer file ready for further digital processing, viewing, electronic publishing, or digital printing.
An image sensor or imager is a sensor that detects and conveys information used to make an image. It does so by converting the variable attenuation of light waves into signals, small bursts of current that convey the information. The waves can be light or other electromagnetic radiation. Image sensors are used in electronic imaging devices of both analog and digital types, which include digital cameras, camera modules, camera phones, optical mouse devices, medical imaging equipment, night vision equipment such as thermal imaging devices, radar, sonar, and others. As technology changes, electronic and digital imaging tends to replace chemical and analog imaging.
In digital photography, the CYGM filter is an alternative color filter array to the Bayer filter (GRGB). It similarly uses a mosaic of pixel filters, of cyan, yellow, green and magenta, and so also requires demosaicing to produce a full-color image.
In digital imaging, a color filter array (CFA), or color filter mosaic (CFM), is a mosaic of tiny color filters placed over the pixel sensors of an image sensor to capture color information.
A laser beam profiler captures, displays, and records the spatial intensity profile of a laser beam at a particular plane transverse to the beam propagation path. Since there are many types of lasers — ultraviolet, visible, infrared, continuous wave, pulsed, high-power, low-power — there is an assortment of instrumentation for measuring laser beam profiles. No single laser beam profiler can handle every power level, pulse duration, repetition rate, wavelength, and beam size.
This glossary defines terms that are used in the document "Defining Video Quality Requirements: A Guide for Public Safety", developed by the Video Quality in Public Safety (VQIPS) Working Group. It contains terminology and explanations of concepts relevant to the video industry. The purpose of the glossary is to inform the reader of commonly used vocabulary terms in the video domain. This glossary was compiled from various industry sources.