How to protect the lidar from the weather?

Question

Do it yourself

There is a circular lidar with an open body:

laser lidar. From the description of the lidar, the maximum laser power is 3MW (as the page on aliexpress says), the laser wavelength is 780nm.
I plan to use it outdoors. He will get caught in the rain. I want to make some kind of case to protect it from water ingress. The question arose of what to make a cap for the sensor itself. I tried a cap made of ordinary glass. It gives small curvature (which is not very critical) and greatly cuts the measurement distance (which is already critical). What are screen protectors usually made of? I met repeatedly lidars with a protective case. Maybe someone knows what material is used as this "colored glass"?

Answer 1

LIDARs do use protective glasses made of plastic, but they can be coated with an anti-reflective coating.
The Chinese sell them - here's an example: https://russian.alibaba.com/product-detail/lidar-l...

Answer 2

Ordinary polycarbonate, it normally passes the near IR up to 1100 nm (lidar usually works at 960 nm). "Colored glass" is a narrow-band filter so that the lidar is not blinded by external illumination.

Answer 3

a large roof in lapping to the laser beam, so that not a drop of rain would fly inside.
and periodic maintenance to erase dust and clean optics.

Answer 4

Judging by Google, which they themselves could use - you need quartz glass.
https://laserspart.ru/katalog-volokonniy-laser/exp...

Answer 5

Glass does not transmit IR rays very well, you should look for a polycarbonate casing.
As for the color of the plastic, dark red plastic is usually used, because red plastic transmits red and IR light but blocks the rest of the radiation. This has a positive effect on the work of lidars. They don't like too much sun exposure.
Expensive lidars use special filters for a certain wavelength and are damn expensive.

Answer 6

As already indicated above, in China there are covers for lidars https://russian.alibaba.com/product-detail/customi...
Pay also attention to the temperature range of the lidar in the datasheet