{"id":3253,"date":"2011-02-08T21:08:48","date_gmt":"2011-02-08T20:08:48","guid":{"rendered":"https:\/\/www.adimec.com\/?p=3253"},"modified":"2018-07-27T17:13:52","modified_gmt":"2018-07-27T15:13:52","slug":"ccd-vs-cmos-image-sensors-in-machine-vision-cameras","status":"publish","type":"post","link":"https:\/\/www.adimec.com\/ja\/ccd-vs-cmos-image-sensors-in-machine-vision-cameras\/","title":{"rendered":"CCD vs. CMOS Image Sensors in Machine Vision Cameras"},"content":{"rendered":"
CCD vs. CMOS Image sensors:\u00a0 The lines are blurring<\/strong>\u00a0<\/strong><\/p>\n
On-Chip system integration<\/li>\n<\/ul>\n<\/td>\n<\/tr>\n
\n
\n
\n
Read noise performance<\/li>\n<\/ul>\n<\/td>\n
\n
\n
Low cost of manufacturing<\/li>\n<\/ul>\n<\/td>\n<\/tr>\n
\n
\n
\n
\u201cPerfect\u201d Global Shutter<\/li>\n<\/ul>\n<\/td>\n
\n
\n
High level of CMOS process innovation<\/li>\n<\/ul>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
In the past, CCDs have been considered superior to CMOS because of their quality. CCD has traditionally offered higher dynamic range and higher resolution. It is generally acknowledged that a lower image quality will result in a lower measurement accuracy and repeatability. Plus, CCD\u2019s inherent electronic shutter eliminates the need for a mechanical shutter. On the downside, CCD frame rates are slower, they require more power dissipation, and they cost more to manufacture and integrate than CMOS.<\/p>\n
Recently, CMOS sensors have shown significant improvements in quality. Now, in addition to the higher speed performance, lower power requirements and higher integration potential of CMOS, CMOS sensor resolutions and data quality are approaching those of CCD sensors. Many are now available with global shutters or snapshot shutters for capturing images of moving objects without distortion. CMOS sensors are closing the gap in noise levels, an area where CCD used to be clearly superior.<\/p>\n
Also, the speed of development in CMOS is faster, since it\u2019s produced in non-dedicated fabs. So sensor prototypes can be developed and incorporated in cameras faster. Sensors are being produced using the same processes as microprocessors and memory chips. These processes are constantly improved in order to make faster and lower power chips. CCD sensors are using dedicated processes with a much slower innovation cycle.<\/p>\n
Market data confirms that CMOS is gaining ground on CCD even in machine vision. This is somewhat distorted if viewed in general terms when consumer applications are considered (CMOS has distinct cost and integration benefits for consumer products). But even in high precision machine vision and other industrial applications, CMOS has emerged as a very viable alternative.<\/p>\n