If you want to know what happened, you have to return the sensors. Find another bad on that you have not taken apart and start the return process. It's called return for RMA. (Return Merchandise Authorization)
But the process is not simple. You have to send the parts back through the chain that you bought them from. Generally, this is a distributor. Sometimes the company doing your assembly bought them from the distributor. It all goes back to ST the same way it came.
That allows us to know who bought them, who soldered them, who stored them and for how long and a bunch of other bits of information that you are not aware of.
But looking at those pictures, there really is only one conclusion. Someone cooked them. They were cooked way too long at way too high a heat.
The sensor's expected lifetime is so long, that your 'cataract' is not age related. It's heat.
Start with your manufacturer, ask them for the refund. If they want to get that refund form their source, they have to provide all the information back up the chain.
Because every one of these sensors has to be calibrated for laser safety, they were all checked at the factory. So returns that were not abused is almost non-existent. But if you really want to know what happened, this is how you go about it.
- john
