| 摘要 |
PURPOSE:To make the result of integration accurate by correcting automatically the error generated by dark current, offset voltage and bias current. CONSTITUTION:When dark current is inputted to an inverted end of an OP amplifier in reset auto-zero mode, dark current component converted to voltage, offset voltage of the OP amplifier itself 3 and error voltage Vd including bias current are generated in the output end of the OP amplifier 3. Input offset voltage of an OP amplifier 15 itself is applied as it is to the noninversion input end of an OP amplifier 16, and becomes integration mode through hold mode. The result of integration of signal component outputted from a detector appears in the output end of the OP amplifier 16 and error component due to dark current, offset voltage etc. does not appear. This is because above mentioned error component is cancelled as it is inputted to differential input end of the OP amplifier 16. |
