CMOS active differential imaging device with single in-pixel analog memory

Active differential imaging is based a pixel-to-pixel differentiation between actively illuminated and non illuminated scene. This imaging device can give very useful ambient light suppression. We have developed an active differential imaging device in CMOS technology with a single in-pixel analog memory. With an original operation sequence, this device can give a differentiated image without any off-chip computation. This device is designed and realized in 0.5um CMOS technology giving a pixel pitch of 12um×12um. Associated with a LED based illuminator, it can be used in many vision applications such as industrial vision, robot navigation, and especially human face recognition.