Sensors & Circuits: Difference between revisions
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===Reflective Optical Sensor=== | ===Reflective Optical Sensor=== | ||
The reflective optical sensor ( Datasheet ) consists of an infrared LED, labelled "E" for Emitter on the diagrand and on the package, and a phototransistor that passes an amount of current proportional to the reflected light received. The phototransistor is labelled "S" for Sensor. The one leg of the sensor is connected to +5V, which supplies current, and the voltage drop across the 10k resistor that we measure is proportional to the amount of current. | |||
There is a continuous voltage response for objects over a short range of proximity to the sensor. The response is not linear. Linearity can be approximated by the log of the log of the signal. | |||
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[[Image:optical.png]] | [[Image:optical.png]] | ||
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Revision as of 04:07, 26 June 2007
Hall Effect
Mulitplexing
IR Distance
Sharp
Reflective Optical Sensor
The reflective optical sensor ( Datasheet ) consists of an infrared LED, labelled "E" for Emitter on the diagrand and on the package, and a phototransistor that passes an amount of current proportional to the reflected light received. The phototransistor is labelled "S" for Sensor. The one leg of the sensor is connected to +5V, which supplies current, and the voltage drop across the 10k resistor that we measure is proportional to the amount of current.
There is a continuous voltage response for objects over a short range of proximity to the sensor. The response is not linear. Linearity can be approximated by the log of the log of the signal.
