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Laser sensor

You may have seen those movies where the spy is trying to break into a high-security compound for some reason or another. There are usually laser beams spread out in places that are impossible to avoid.

Laser sensors are an important part of security applications. The following is a photograph of a laser sensor:

There are three pins in the preceding laser sensor. They are as follows:

VCC: For power
GND: For ground
DOUT: For digital output signal

The following is a simple alarm system using a laser sensor. As with our smart garden, the processing logic programmed onto the Raspberry Pi makes this an edge analytics application:

Light Amplification by Stimulated Emission of Radiation, or LASER for short, had its origins in the theoretical foundations of Albert Einstein in 1917. The year 2020 marks the 60 ^th anniversary of the laser as Theodore H. Maiman of Hughes Research Laboratories invented the first one in 1960. Early lasers were used in medical procedures. Today, we may find lasers in everything from DVD players to laser pointers and Light Detection and Ranging ( LiDAR).

By having the processing done on the Raspberry Pi, we can limit or modify the data sent to the cloud. For example, the logic may be programmed to send text messages only to certain people at night or on weekends.