A CMOS focal-plane rotation sensor with retinal processing circuit

Abstract

In this paper, a CMOS focal-plane rotation sensor with the retinal processing circuit is proposed and implemented. The proposed rotation sensor has a polar structure and is selective to the angular velocity and direction (clockwise and counterclockwise) of the rotating images. The selected angular velocity depends on the frequency of an external clock signal, which can be precisely adjusted. In the proposed rotation sensor, there are 104 pixels, which form five concentric circles. The area of a single pixel is 91x84 mum(2) with a fill factor of 20% whereas the chip area is 1812x1825 mum(2). It is found from the experimental results that the detectable angular velocity and illumination range of this rotation sensor are from 2x10(-2) pi/sec to 206 pi/sec as well as from 0.91 lux to 366 lux under a contrast of 80%, respectively.