Apple patent application US20150312479 "Image sensor having a uniform digital power signature" by Andrew Mcmahon, Chiajen Lee, and Michael Malone says "there is a need for a system and technique for reducing the effect of digital logic interference on the quality of a digital image. The techniques disclosed herein can be used to produce a digital image having reduced or minimized visual artifacts without significantly increasing the size of the sensor or the drawbacks of some traditional noise reduction techniques."
Apple proposes to add dummy operations 525 to the digital pipeline, so that the digital noise is substantially constant in all time slots:
Wow, you increase the noise of the system to reduce it visually! Incredible new, patentable invention!
ReplyDeleteBTW: It's a well-known approach to stabilize the readout offset of CCDs by continously driving its readout circuitry!