In the circuit, the voltage at pin 3 is set by VR1 so as to keep the output high in a particular light level. The high output keeps the LED off. The PN Photodiode act as the light sensor. When the ...

The circuits works off a well regulated 5Volt dc supply. When power is turned to ON, light transmitter D1 starts emitting visible red color beam towards outside through a red colored filter glass. If ...

Automation light grids take many forms and cover applications from simple to complex. Sizes range from a few inches to several feet, and resolutions from 2 to 100 mm. Nearly every sensor ...

The sensor in this application, a BPW21R photocell (from Vishay), is used to generate photocurrent proportional to the ambient light intensity (see the figure).

Finally, they also tested how fast the sensor reacts to an object which appears in the beam. They did this by shooting a knife blade into the laser beam with a speed of 27 metres per second. The laser ...