Patent attributes
Provided is an optical image receiving device having a high and rapid sensitivity and a wide dynamic range manufacture in a CMOS process. The image receiving device includes a capacitor transistor for a special purpose in addition to a general structure of three transistors and a light receiving portion. The capacitor transistor has first and second source/drain ports connected to the capacitance node and the floating diffusion node, respectively, and is gated in response to activation of a predetermined capacitor control signal. In the CMOS optical image receiving device, the floating diffusion node is pumped over an external power voltage. Thus, the electronic potential of the floating diffusion node in the initialization state is much higher than the maximum voltage of the light receiving portion. Thus, the CMOS active pixel has a very high sensitivity in a region where the intensity of light is weak. Furthermore, since the sensitivity decreases in a region where the intensity of light is strong, the dynamic range thereof can be increased very large.
