charge-coupled device

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Related to CCD imager: charge-coupled device, CCD sensor

charge-coupled device

See CCD.

charge-coupled device

[′chärj ¦kəp·əld di′vīs]
(electronics)
A semiconductor device wherein minority charge is stored in a spatially defined depletion region (potential well) at the surface of a semiconductor and is moved about the surface by transferring this charge to similar adjacent wells. Abbreviated CCD.

charge-coupled device

(electronics)
(CCD) A semiconductor technology used to build light-sensitive electronic devices such as cameras and image scanners. CCDs can be made to detect either colour or black-and-white. Each CCD chip consists of an array of light-sensitive photocells. The photocell is sensitised by giving it an electrical charge prior to exposure.

CCD sensor

(Charge-Coupled Device sensor) An electronic memory that records the intensity of light as a variable charge. Although mostly replaced by CMOS sensors to capture images in cameras, camcorders and scanners, CCDs are still used in astronomy, microscopy and biomedical imaging because of their excellent sensitivity during long exposures.

CCDs are analog devices. Their charges equate to shades of light for monochrome images or shades of red, green and blue when used with color filters. Devices may use three CCDs, one for each of the red, green and blue colors.

Why Coupled?
The CCD comprises an array of imaging pixels and a matching array of storage pixels that are coupled together. After the imaging array is exposed to light, its charges are quickly transferred to the storage array. While the imaging CCDs are being exposed to the next picture, the storage CCDs from the last picture are being read out a row at a time to the analog-to-digital converters (A/D converters) that transform the voltages into binary data to be processed. Contrast with CMOS sensor. See Bayer pattern, X3, Super CCD, blooming and digital camera.


Charge-Coupling Methods
The storage CCDs are either a separate array (frame transfer) or individual photosites (interline transfer) coupled to each imaging photosite. The charges can be transferred faster with the interline method because each storage component is closer to its imaging counterpart.







CCDs Record Light
In a camera, CCDs take the place of film. They are exposed to light, recording the intensities, or shades, of light as variable charges. In the digital camera above, the variable, analog charges in the CCD are converted to binary data by analog-to-digital converter chips.







CCDs Are Sensitive
This CCD from Jet Propulsion Labs is used in astronomy. Sensing the output of telescopes, it detects ultraviolet light from distant planets. (Image courtesy of JPL's Microdevices Laboratory; Robert M. Brown, photographer)
References in periodicals archive ?
The new DSC-P31 and DSC-P51 models offer 2.0 megapixels (effective) of resolution, while the top-of the-line DSC-P71 provides 3.2 megapixels (effective) from its CCD imager.
For example, a CCD imager has a life span of at least five years compared to the two years of a general purpose tube.
While the MiniDV format delivers a powerful combination of precise image detail and vivid colors, three of Sony's new MiniDV models take video resolution even further with the incorporation of megapixel CCD imagers. Two models, the DCR-TRV25 and the DCR-TRV27, feature a 1,070k-pixel CCD imager, which produces outstanding video at 520 lines of horizontal resolution.
There is clearly more work to be done here by both the visual observer and the CCD imager, and I would like to suggest this as an observing project suitable even for those with modest telescopes.
Some astrophotographers, like Portuguese CCD imager Antonio Cidadao, take only R and B exposures and create the G component by averaging the first two.
For the dedicated deep-sky observer and CCD imager who needs a source of interesting objects and the finder charts to go with them, MegaStar is probably close to ideal.
Khan, a respected astrophotographer and CCD imager, stepped forward to run the WSP because he believes it's an important event.
Senior editor Dennis di Cicco, an experienced CCD imager, used the AP8p with optics ranging from medium-format camera lenses to a Meade 40-cm (16-inch) LX200.
Although a tough visual challenge, Amalthea is well within reach of skilled CCD imagers. For instance, professional astronomers recorded eclipses of Amalthea during the marvelous series of mutual events among the Galilean satellites from September 2014 to June 2015.
The Ikegami HDL-45E is a multi-purpose HD camera with three 2/3-inch 2.3 megapixel AIT CCD imagers, an LSI processor and high quality 14-bit analog to digital converters.
The instrument simplifies assay transfer from development to screening labs by delivering the object recognition of CCD imagers combined with the fast reads of bulk fluorescence readers.
The first was CCD imagers and the need to get them to photographic resolution.