Phidget 1045 IR Sensor - Cover ?

[Alistair]

Hello,

I am using the 1045 IR Sensor as a cloud detector, and this is working well. I have the acrylic casing the IR sensor can be housed in, but still the barrel of the sensor is exposed to the elements. So I am looking for a suitable cover to fit over the top.

So far I hove found out the wavelength pass band of the optical filter used is from 5.5μm to 14μm. So my thought process is that if I can also make a cover that will pass this range then this should work. However I am having no luck.

Glass is obviously no good as it absorbs "thermal IR". White shopping bags seem to let about 60% of the IR through, but I was looking for something better without having to resort to exotic materials like Quartz\Germanium or Zinc Suphide (which are very expensive).

Is there some simple solution to cover the senor of this phidget ?

Thanks

Alistair

[mparadis]

This isn't exactly a cheap solution, but a readily-available one- there are photography lenses (longpass filters) that are designed to pass light beyond a specified wavelength. Maybe if you're lucky you could get a used one for cheap?