Touch

A type of switch that has to be touched by an object (usually the finger) to operate. It is used in many lamps and wall switches as well as on public computer terminals. There is an array of touch switches on a touch screen display.

Laser Ranging

Laser ranging, known as LIDAR (Light Detection And Ranging) is an optical remote sensing technology which measures the properties of scattered light to find the range of a distant target. The most common method to determine the distance to an object is to use laser pulses. Often used by police in capturing speeds of vehicles.

Ultrasonic

A cyclic sound pressure with a frequency greater than the upper limit of human hearing. The production of ultrasound is used in a variety of fields, typically to penetrate a medium and measure the reflective properties or achieve focused energy.

Rotary Encoders

Also referred to as a shaft encoder. This is a sensor which generates an electrical signal responding to rotational movement. The signal is then used to ascertain or control the speed/position of a mechanical device.

Light

An electronic or mechanical device that can detect light. Primarily used to supply information on distance, speed, dimensions, shape and even types of substances found in a variety of objects.

Motion

A motion sensor is used for electronic motion detectors which converts the detection of movement into an electrical signal. This is accomplished by measuring the optical or acoustical variance in its field of view. Most of these devices can detect up to 15-25 meters (50-80 feet).