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Code or name of LDR with special design

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New Member
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.



Well-Known Member
Most Helpful Member
From the photos that appears to be more like some type of large-element photodiode or tiny photovoltaic cell, not an LDR.
It's certainly not like any I have ever seen, with an even dark blue or near-black element area.

Normal LDRs typically have a very obvious "interleaved finger" appearance.
eg. https://leetechbd.com/wp-content/uploads/2018/01/LDR-10-mm-Photo-Resistor.jpg

If that actually is one, it may have some kind of optical filter layer over it to limit it's response?

This looks more like yours; note the element appearance:

Edit - just noticed it has "+" next to one terminal; LDRs are not polarised, so it is not one of those.
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Nigel Goodwin

Super Moderator
Most Helpful Member
$2.99 each seller is in Georgia FREE postage. For only $3 give it a try.

You can buy 30 of these from China $1.23 total with free postage but you have to wait a month for them to arrive. I bought 1 i only needed 1 and did not want to wait a month.

Perhaps you should try reading the previous posts?, or even looking at the picture the OP posted?, it's NOT an LDR so not much point buying any.
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