Digital Image Sensor by pawan

Apr 26, 2018 Written by Pawan Negi Digital Image sensor


                                               Digital image sensor

1.A digital camera uses an array of millions of tiny light cavities or "photosites" to record an image. When you press your camera's shutter button and the exposure begins, each o these is uncovered to collect photons and store those as an electrical signal. Once the exposure finishes, the camera closes each of these photosites, and then tries to assess how many photons fell into each cavity by measuring the strength of the electrical signal. 

2.A charge couple device (CCD) is a device for the movement of electrical charge, usually from within the device  to  an area where the charge can be manipulated, for example conversion into a digital value.

3.This  is achieved by shifting  the signals between stages within the  device one at time.

4.Although  CCDs  are not the only technology to allow for light detection, CCDs are widely  used in professional, medical , and scientific applications where high-quality image data is required.           

5.Complimentary metal – oxide- semiconducte (CMOS) is a technology for constructing integrated circuits.

6. CMOS technology is used in microproccessors , microcontroller, static  RAW, and other digital logic circuits.

7. Two important characteristics of CMOS device  are high  noise immunity and low static power consumption.

8. Three CCD or 3CCD is a term used to describe  an imaging system employed by some still cameras, video cameras, telecine and camcorder.

9. Three CCD cameras have  three separate charged –couple devices (CCDs),  each  one taking  a separate measurement of red, green, and blue light.

10. Compared to cameras with only one CCD , three-CCD cameras generally provide superior image quality and resolution.