Patent ID: 7095440

Claim:
An active pixel sensor, comprising: a photodiode part located at least partially in a substrate and constructed to accumulate a signal indicative of incoming light during an integration period; a floating diffusion part located at a first side of said photodiode part, selectively connected to receive said signal from said photodiode part; a transfer barrier gate, having a bias level which allows said signal to pass from said photodiode part to said floating diffusion part; a buffer, connected to sample a signal on said floating diffusion part; a storage region located at a second side of said photodiode part in said substrate for receiving excess charge from said photodiode part at an end of said integration period; and at least one flood and spill control part, connected to at least said photodiode part and controlling flooding of at least said photodiode part to provide a known initial condition on said photodiode part.