Laser based Alarm System. Sensor Circuit.17

It is easy to construct a Laser based Relay activator to operate Alarm systems or to switch on CCTV or Auto Camera when there is any attempt of theft. It can be used to guard, doors, entry passages etc. The circuit uses Laser beam so that the range of the circuit is more than 10 meters and there is no false triggering.

Laser diode is similar to LED and emits Monochromatic narrow laser beam that passes long distance through air. The Laser diode requires 3 volts and around 100 mA current for getting maximum range. So the current limiting resistor must be selected as per the range. A China make low cost laser torch can be used for the purpose.
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Trick to Exploit Calculator Solar panel

Don’t throw away your old calculator. Its Solar panel can be used to make a Broken beam alarm or Automatic LED lamp. Let us see two circuits exploiting the photovoltaic property of the tiny calculator solar panel .

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Laser Scan Confocal Microscopy

Confocal microscopy is an imaging technique used to increase image contrast and to reconstruct three-dimensional images by using a pinhole to eliminate out-of-focus light in specimens that are thicker than the focal plane.

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Laser is a narrow beam of Photons emitted by specially made laser diodes. Laser diode is similar to an ordinary LED, but it generates a beam of high intensity light. A laser is a device in which a number of atoms vibrate to produce a beam of radiation in which all the waves have single wavelength and are in Phase with each other.
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Compact Disc.How it store data?

A Compact Disc (CD) is an optical disc used to store digital data. CD-ROMs and CD-Rs remain widely used technologies in the computer industry.CD-ROM drives employ a near-infrared 780 nm laser diode. The laser beam is directed onto the disc via an opto-electronic tracking module, which then detects whether the beam has been reflected or scattered.

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