Sunday, November 7, 2010
Light Sensors are used to measure the radiant energy that exists in a very narrow range of frequencies basically called "light", and which ranges in frequency from "Infrared" to "Visible" up to "Ultraviolet" light. Light sensors are passive devices that convert this "light energy" whether visible or in the infrared parts of the spectrum into an electrical signal output. Light sensors are more commonly known as "Photoelectric Devices" or "Photosensors" which can be grouped into two main categories, those which generate electricity when illuminated, such as Photovoltaics or Photoemissives etc, and those which change their electrical properties such as Photoresistors or Photoconductors. This leads to the following classification of devices.
For more info, see http://www.ecs.umass.edu/ece/m5/tutorials/CdS_Flex_Sensor.html
Posted by Steve Spence at 7:35 AM