RM9 7Y70669 with Chopper

Overview of RM9 radiometer system:

User's Manual

RM9 radiometer system is a combination of sensor and beam chopper, which is used to measure the power of very low level CW or quasi CW light source. The RM9 sensor has a pyroelectric element, which can measure radiation in a wide dynamic range, from less than 100nW to 100mW. It has an 8mm aperture and covers the spectral range from 0.15 µ m to 12 µ m. The system has an RMC1 chopper placed between the source and the RM9 sensor.  When installing the chopper, the side marked "THIS SIDE TOWARD SENSOR" should face the sensor.

RM9 Radiometer Drawing：

Main parameters:

Problem summary:

How to use RM9 radiometer to greatly improve the measurement accuracy?

RM9 is only sensitive to signals chopped at 18 Hz, so placing the chopper as close to the laser source as possible can greatly reduce stray light entering the chopper and being read as part of the signal.

The noise specification is based on a 10 second moving average and the power meter is set to the average of the measured values for better performance.

It is recommended to zero the sensor before use by disconnecting the BNC cable between the RM9 sensor and the chopper or closing the chopper.

Can RM9 be used to measure pulsed laser power?

Yes, but RM9 will measure average power, not energy. In addition, pulse rates below 50 Hz may generate additional noise. A pulse rate close to 18 Hz may cause beat problems.