Power Meters FAQ's

Thermal Laser Power Sensors

Radiometer

Why does the chopper have a defined orientation "THIS SIDE TOWARD SENSOR"?

08/26/20

Typical choppers have the same type of surface on both faces: either metallic, low emissivity or black, high emissivity.
When blocking the laser beam, metallic surfaces will reflect or scatter a significant portion of the laser power which may result in stray reflections reaching the sensor.
Black surfaces solve this issue, but if the chopper is positioned close to the RM9 or RM9-THz sensor, they will pick up a thermal signal from the chopper blades.
Stray reflections and thermal signal from the blades can impair measurement accuracy.
Our chopper enjoys the best of both worlds. It has a black surface that should face the laser beam and a low emissivity surface that should face the sensor.

I know the “SH to BNC Adapter” can be used to get a raw analog signal from power sensors. Can I use it to get a raw analog signal from an “RM9” radiometer sensor?

02/14/21

The SH-to-BNC adapter will not work with the RM9 series. The RM9 needs software control from the host meter to set up its scales and settings; it is not a simple voltage or current source like a regular Thermal or Photodiode sensor. It has its own PCB and it needs power from the host meter.