Hello everyone, I'm new to these forums and hope to get some help. During the maintenance to a broken equipment, I could find that the error was a ldr of special design (not sensitive enough to respond to the stimulus of a laser). I have searched all the electronic stores that I know but they had never seen the model. I would appreciate if any of you gave me the name of this ldr or the code to buy a spare part from abroad. Thanks.

 

Welcome to AAC
Are you sure it's not a conventional CdS cell? They're normally that shape. Their resistive element is spread out, so a sharply focussed laser beam might not affect them much.
CdS cells are becoming rarer, because of Cd being toxic, but you still find them in things like cheap auto-turn-on night lights from dollar-stores.

Edit: The + and - marks suggest it's a polarised device, which rules out its being a CdS cell.

 

If you can make sure that it is a LDR then you can buy one from your local store to try, because it could be a product made by order, so you can't buy it in the local store or online shop.

 

That is a silicon photosensor
SG
.https://www.alliedelec.com/product/...0219662/?&mkwid=suL8Np2F5&pcrid=30980760979&p