Abstract: A Contact Image Sensor (CIS) system with high resolution, high sensitivity, low noise, low-power dissipation, and low-cost scanning has a CIS pixel structure that utilizes a junction photodiode as a detector element and a single-stage, high-gain, low-power inverter functioning as a charge integrating amplifier. The inverter clamps the photodetector at a fixed bias voltage and removes any signal charge generated by the incident light. A very small integrating capacitor is used on the integrating inverter amplifier for high pixel gain. The pixel further includes a noise cancellation circuit to eliminate the reset noise of the integrating capacitor. The pixel signal is then read out by a differential stage to cancel the dark offset. This structure allows the implementation of high-performance CIS arrays using low-cost standard CMOS manufacturing process.