CCD
More info
- Creator
- Willard Boyle & George Smith
- Released
- 1969
- Type
- Image sensor
A light-sensitive chip that marches charge packets in line to an amplifier — the sensor in scanners, fax machines and early digital cameras.
The charge-coupled device was invented in 1969 by Willard Boyle and George Smith at Bell Labs — work that earned them the 2009 Nobel Prize in Physics. It is essentially an analog shift register: incoming light frees charge in each pixel, and clock pulses march the charge packets step by step to a single amplifier that reads them out in sequence.
A flatbed scanner uses a row of CCD elements behind a lens to capture one image line at a time; the same trick gave sharp reading heads to fax machines, barcode readers and the first digital cameras. Cheaper, lower-power CMOS sensors have displaced CCDs since the 2010s, except in scientific imaging.