Willen
Well-Known Member
According to few reading and few experiment, I know that each and every junctions produce light (tiny amount in transistor junction, huge amount in LED) during operation. So transistors and ICs are packed by black epoxy to save from light affect. So we can get some unusual benefit from transparent LEDs or dioodes (like 1N4148).
I experimented with a green light as a light detector, shown below. How actually it works? Sure not like a LDR. I think it passed few volt and current above than 0.6V (forward voltage across the LED) so PNP conducts. Few more analysis needed.
I experimented with a green light as a light detector, shown below. How actually it works? Sure not like a LDR. I think it passed few volt and current above than 0.6V (forward voltage across the LED) so PNP conducts. Few more analysis needed.
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