Cover glass for VL53L4ED

[kossiN]

I am putting together a water level sensor based on the vl53l4ed. The device will be in an outdoors setting with wild swings in environmental conditions. I am having hard time to design a cover / cover glass system for the TOF sensor. I have now concluded that it would be best to purchase a pre-made cover glass assembly for this sensor.  I expect accumulation of dust and other contaminants on the cover glass over time so I would prefer a zero calibration option with individual emitter and receiver covers separated by a divider. Are there commercial cover glass options available for the vl53l4ed model? I found a few options on the ST website but none for the vl53l4ed. Also, are there vendors in the USA who carry these cover glasses? If available, the vendor has to be NDAA-compliant.

Thanks

[John E KVAM]

Years ago, ST worked with a company - www.hornix.com.tw  to develop such a coverglass. It was for the VL53L0. But the L0, the VL53L3, the VL53L4 (Both CX, CD and ED) are all the same shape. So the same coverglass works for all of them. 

Hornix is in Taiwan (hence the .tw) in their name. However, they have proven to be a reliable vendor for many years. On the ST web site is another company - Gilisymo ToF Cover Glass Family

But Gilisymo deals in development quantities. And they re-sell the same Hornix coverglass in Europe. 

They are good folks, but not practical in large quantities or for US customers. 

Note that ST is not involved in either of these companies, but they distribute parts that make using the ToF easier. We are just good friends. 

I don't think NDAA is going to be an issue. Hornix is in Tiawan. So you are OK there.

Water detection is somewhat problematic. It works, but everyone wants more accuracy, and the signal return is challenging. Read the accuracy section of the datasheet as it relates to temperature. The ED device will work in extreme conditions, but not with the same accuracy. So be a little careful here.