一种大动态范围近红外光功率测量电路设计

Design of A Near-Infrared Optical Power Meter Circuit with Large Dynamic Range

基于铟镓砷(InGaAs)光电二极管设计了一种大动态范围近红外光功率测量电路。在不使用外置光衰减片的条件下,它可以测量-95~10 dBm范围内的近红外光功率。该光功率测量电路采用了自动偏压控制、多档放大量程、差分采样电路等技术,并通过电磁屏蔽设计抑制了杂散光噪声和电路暗噪声,从而提高了测量动态范围。测试结果表明,这种近红外光功率测量电路的动态范围达到105 dB,在-60~10 dBm范围内的线性度优于±0.02 dB。

A near-infrared optical power meter circuit with large dynamic range is designed based on indium gallium arsenide(InGaAs)photodiode.It can measure near-infrared optical power in the range of-95--10 dBm without using an external optical attenuator.The optical power meter circuit adopts technologies such as automatic bias voltage control,multi-level amplification range,differential sampling circuit,etc.,and suppresses stray light noise and dark noise through electromagnetic shielding design,thereby improving the measurement dynamic range.The test results show that the dynamic range of this near-infrared optical power meter circuit reaches 105 dB,and the linearity in the range of-60-10 dBm is less than±0.02 dB.