M2131型测光探测器是由侧窗光电倍增管、高压电源、分压电路组成。该测光探测器直接输出电流信号，可以采用电阻调节或电压调节两种方式控制增益。 提供M2131-01和M2131-02两种型号可选。

The M2131 series is a photosensor module consisting of a side window photomultiplier tube and a high-voltage power supply circuit.The photosensor module can output the current directly, and the sensitivity can be adjusted by control voltage that connected externally or using a potentiometer. Two models are available: M2131-01 and M2131-02.