Photocell
(Redirected from Photoresistor)

From bildr

Jump to: navigation, search


ImageNeeded.png

A photocell, also known as a photoresistor, photoconductor, light dependant resistor (LDR), or cadmium sulfide (CdS) cell, is a resistor while resistance varies according to light intensity.

Photocells are inexpendive light detectors with a slow rate of light detection, making them ideal for many comsumer applications such as camera light meters and street lamps.

Photocells are typically cadmium sulfide cells, but some specialty applications may use different sensors, such as Lead sulfide (PbS) and indium antimonide (InSb) sensors for the mid-infrared spectral region, and germanium copper (GeCu) photocells for the far-infrared spectral region.


Contents

Technical Details

A photoresistor is made from a high-resistance semi-conductor whose face is exposed to light. Light of high enough frequency causes photons of the semi-conductor to give off electrons, causing the semi-conductor to switch into the conductor band, thus changing its overall resistance.

Photocells do not provide linear voltage in respect to the amount of light.

Code



This page is a Component on bildr. Components are pages about specific parts, and include connection details and code when available.

Retrieved from "http://wiki.bildr.org/index.php?title=Photocell&oldid=7615"

NOTE: All information contained within this article is pure opinion. Although this article is intended to help people, it may contain faulty or misleading information. This article is not to be considered professional opinion or advice, and is in no way a replacement for reading all safety/instructional documentation. Always remember to protect yourself when handling/using hazardous materials, as well as test new techniques before using them on projects/work intended to be handed in or used.

bildr and its contributers take NO responsibility for the information contained within.