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Physical Mounting

A project log for Open Source Laser Power Meter

A simple USB silicon pin photodiode based laser power meter

b-a-bryceB. A. Bryce 06/10/2016 at 23:200 Comments

With the first cut electronic design largely squared away conceptually, I turn to the physical mounting of this power meter.

The expensive commercial power meters tend to have heatsinks on them to stabilize the detector. This could be a problem at high powers for the current design but it won't be clear until it is built.

Apart from dissipating heat the system has to be mounted to an optical post. In the past I have taken the approach of using a cage plate and tapping it to mount the PCB.

Here is an example of an amplified photodetector I did in the past.

In the current device I will probably use an SM1 thread cage plate, which is available for imperial and metric posts. This will allow lens tubes or mounted optics to be used with the power meter, which will simplify the use of neutral density (ND) filters use or focusing optics if the beam diameter is larger than 4 mm.

My standard mounting method is not shielded but a cover could be produced at need.

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