针对光电二极管电压型放大器在辐射探测系统引起的非线性响应,分析并验证了光电二极管电压放大器在稳定辐射探测中,主要因响应度受到调制而出现响应非线性;在脉冲辐射探测中,影响系统线性度的是电压放大器中的带宽调制现象;提出了将带有电压跟随器的互阻放大器作为各种辐射探测的解决方案;阐明了从线性度考虑出发,用光电二极管互阻放大器代替电压式放大器的合理性。
Photodiodes have many advantages that make them broadly used in radiation detection systems. However, the nonlinear responsivity caused by photodiode voltage amplifier still needs to be emphasized and investigated. In the article, it is analyzed and proved that if a photodiode voltage amplifier is applied, in cw measurement, nonlinearity is caused by the modulation of photodiode responsivity, and in pulse energy measurement, by the modulation of bandwidth. Linear responsivity of the transimpedance amplifier combined with bootstrapping is demonstrated and its necessity for being used as a solution to substitute voltage amplifier is pointed out.