Thermal laser power sensor or photodiode: making the right choice

greenTEG: Did you ever come across a situation where you had to decide between a thermal laser power sensor and a photodiode? Several parameters determine whether a photodiode or a thermopile sensor is the best choice for a specific application. To help you with this, we compared a silicon photodiode and the gRAY B0.5-SC regarding their spectral range, response time, linearity with power etc.

Compared to silicon photodiodes, thermopile sensors score with a large range of detectable wavelengths – especially outside the visible range. The gRAY B0.5-SC with a sensing area of 2 x 2 mm2 comes in a convenient SMD package which additionally ensures a superior thermal contact after soldering. This makes it a compact, affordable choice for measuring power levels larger than 100 μW in confined spaces. Photodiodes, however, possess a superior response time and are thus well-suited for the detection of fast power changes (such as single pulses) and very low intensities in the nW range.

Key Features of the gRAY B0.5-SC

• Very compact thermal detector
• Sensitive to all wavelengths from UV to MIR
• Powers of up to 500 mW
• Linear power response
• Attractive OEM pricing