Visible and Infrared Light Detectors

Posted on Jun 4, 2012

The sensors used are silicon phototransistors and Cadmium Sulfide (CdS) photocells. Both of these sensors allow less current to flow when they are dark than when lighted. Phototransistors change their conductance while photocells change their resistance depending on the intensity of the light falling on them. All of the detectors on this page use LM339 Quad or LM393 dual voltage comparator integrated circuits to detect the change in voltage across the sensor. For information on Voltage Comparators please see the Voltage Comparator Information page at this site.

Visible and Infrared Light Detectors
Click here to download the full size of the above Circuit.

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Navigateur   Jul 1, 2008

Top top top class website! Thank you so much to the author R Paisley!!! What a hero. You teach people and change the world by doing so. 10 stars rating given, highly, highly, highly recommended to everybody reading.

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