# LDRs Preferably cadmium sulphide LDRs

1. Mar 3, 2004

### BLUE_CHIP

It would be really helpfull if you could give me a few links on LDRs

Preferably cadmium sulphide LDRs.

I'm looking for the internal structure, chemical properties of cdS, and relationships between light intensity and resistance and if possible, light wavelength and resistance.

I've been looking for a while but cant find anything.

thank you

2. Mar 3, 2004

### Integral

Staff Emeritus
Whats an LDR?

3. Mar 3, 2004

### BLUE_CHIP

Sorry, I didn't clarify.

A Cadmium Sulphide Light Dependant Resistor (LDR)

I thought that it was an accepted abbreviation.

4. Mar 3, 2004

### Integral

Staff Emeritus
I have never heard or seen that acronym, are these photo diodes? Perhaps your difficulty in finding information is because LDR in not a common term. (Just guessing)

5. Mar 3, 2004

### BLUE_CHIP

An "LDR" is a photoconductive cell for which the equation:

$$lnR=(ln[lux])^{-1}$$

applies, where R = Resistance of cell
lux = intensity of light falling on cell

6. Mar 3, 2004

### Integral

Staff Emeritus
Try including photo diode in your search string instead of LDR. I had some interesting hits with that.

7. Mar 3, 2004

### pallidin

Here's one link I found: www.electrovalue.co.uk/pdf/o-p.pdf [Broken]

THere are others. I used these search words in Google: Cadmium Sulphide Light Dependant Resistor

Last edited by a moderator: Apr 20, 2017 at 7:16 PM