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Well that's a quite simple question. I tried my chance with Google Images without success and tried some lists of images to be able to know what is this component. But I don't find it and there is nothing written on it.

enter image description here

Chetan Bhargava
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rels
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1 Answers1

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This is Light dependent resistor (LDR).

Its similar to a normal resistor, but the resistance decreases with increasing light intensity.

Rev
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O.Blue
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  • Perfect! Thank you O.Blue I can put a sticker on it now :) – rels Feb 20 '16 at 14:19
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    If the answer seems good to you, don't forget to accept it (button just below the up/down vote arrows). It allows to mark the question as answered – MaximGi Feb 20 '16 at 14:37
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    Possibly worth mentioning that these are generally based on Cadmium Sulfide (CdS), and are therefore not RoHS-compliant (Cadmium is on the no-no list). Use ambient light sensor (the generic term) for plenty of RoHS-compliant options. – Calrion Feb 21 '16 at 05:57
  • Do they only work for visible light or can you get ones for ultraviolet, infrared, etc light as well? – Pikamander2 Feb 21 '16 at 06:31
  • @MiximG wanted to do it straightly but had to wait "10 minutes" and had to go, so it's done only now. – rels Feb 22 '16 at 07:43
  • @Pikamander2 the vast majority work in the visible light region. You'd probably want a different sensor for other regions (photodiode, etc.) – rdtsc Feb 24 '16 at 04:32
  • @Pikamander2 I know this is a couple years late, but a cadmium selenide photocell will work for visible light down to about 700nm wavelength (deep red, nearly infrared) and any higher energy (shorter wavelength) light. Pure cadmium sulfide cells won't work for red or yellow light, but they'll work for green light and any higher energy light. It depends on the bandgap of the semiconductor used in the photocell. – Hearth Apr 25 '18 at 18:00