Patent ID: 7623169

Claim:
A method of operating a charge gain hybrid imaging system comprising: activating an amplifier reset switch to reset a charge amplifier; collecting a charge of a pixel of the imaging system; storing the collected pixel charge in a pixel capacitor (C p ); selecting the pixel via a pixel select switch; activating a pixel reset switch to reset the pixel; deactivating the amplifier reset switch, wherein a gate-source capacitive charge is injected into a front end of the charge amplifier; transferring the pixel charge stored on the pixel capacitor (C p ) to a data line capacitor (C d ) of a data line until a full data line charge, which is associated with an effective charge gain of C d /C p , is reached; activating an amplifier select switch connecting the data line to the charge amplifier, the gate-source capacitive charge detected by a first sampling action of a sample switch, wherein the active state of the amplifier select switch encompasses the first active state of the sample switch and the charge of the data line capacitance is transferred to the charge amplifier as the charge gain defined by the relationship C d /C p ; sensing the data line charge by the charge amplifier; deactivating the amplifier select switch after the pixel is selected, to isolate the pixel from the charge amplifier; and activating the sample switch a second time, wherein an output of the charge amplifier due to the charge gain is detected.