Point Grey publishes a white paper comparing EMVA1288 measurements of Sony ICX274 CCD with global shutter CMOS sensor IMX174:
Point Grey also promises to reveal Sony's new generation global shutter CMOS sensor, the IMX249, in its pre-Vision Show Youtube video.
ICX274 with 65% QE? Old charts give it ~45% max.
ReplyDeleteI don't understand in all sense the CMOS is better than CCD? What are we missing here? Or perhaps a badly designed CCD?
ReplyDeleteIndeed, why does a CCD still exist? Is it cheaper to produce or is it due to processors expecting CCD-like digital signals?
DeleteModern CMOS is a tiny CCD inside each pixel. The readout is in parallel by line, so the bandwidth is smaller than CCD which uses pure sequential high speed readout. That is why average noise is low, but some other noise sources emerge in CMOS, such as 1/f, fixed pattern noise, etc.
ReplyDeleteThis SONY GS sensor is master piece !
Anyone knows the shutter efficiency? How do they shield the tiny CCD element inside pixel?
ReplyDeleteCMOS IMX174 is a new technology (2 years) and the CCD ICX274 is a much older technology (14 years). A better comparison would be the the CCD ICX674. This CCD has a QE max of about 75%. QE comes down to AR coatings, and the later technologies are just better for AR. CMOS and CCD for QE are to first order, irrelevant. In fact, for pixels this begin, there is little benefit for even going backside.
ReplyDelete