| 摘要 |
An imaging element[40, 110, 120] and an imaging array [100] constructed from such elements. The preferred imaging element[40, 110, 120] is constructed from a photodiode[41, 114] having a parasitic capacitance Cpd; and an amplifier for measuring the charge stored on the parasitic capacitor[42, 115]. The amplifier includes an opamp[43, 59, 111] having a signal input, reference input and output; the first terminal of the parasitic capacitor [42, 115] is connected to the signal input. The imaging element[40, 110, 120] includes a reset switch[45, 51, 113] for shorting the signal input and the output of the opamp[43, 59 111], and capacitive network. The capacitive network connects the signal input and the output of the opamp[43, 59, 111], and provides a capacitance of CT between the signal input and the output of the opamp[43, 59, 111] wherein CT<Cpd. The capacitive network is constructed from a plurality of component capacitors[46, 47, 48]. Preferably each component capacitor[46, 47, 48] has a capacitance greater than or equal to Cpd. An imaging array [100] according to the invention includes a plurality of imaging elements[110, 120], a signal bus [131], a reset bus [132], and a reset circuit. Each imaging element[40, 110, 120] also includes a coupling switch for connecting the output of the opamp[43, 59, 111] to the signal bus[131] and a reset coupling switch[134] for connecting the photodiode[41, 114] to the reset bus[132] via a low-pass filter[116, 117]. The reset circuit includes a second opamp[133] having a signal input, a reference input connected to a second reference potential, and an output connected to the reset bus[132]; and a reset coupling switch[134] for connecting the signal input of the second opamp[133] to the signal bus[131].
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