A wide dynamic range CMOS image sensor based on a new gamma correction technique

Many kinds of wide dynamic range (WDR) CMOS Image Sensors (CIS) have been developed, such as a multiple sampling, a multiple exposure technique, and so on. However, those techniques have some drawbacks of noise increasing, large power consumption, and huge chip area. In this paper, a new Single-Slope ADC (SS-ADC) for gamma correction with a nonlinear counter is described. Since the proposed scheme is easily implemented with a simple algorithm, we can reduce power consumption and chip area drastically. Further, the new SS-ADC for gamma correction enhances the Dynamic Range (DR) by 24dB. The proposed ADC, which has been fabricated using a 0.13um CIS process, achieves a 57.6dB SNDR at 50kS/s.