The options when specifying sensors for long-range object detection or positioning usually boil down to two alternatives: optical sensors using either infrared or visible-red light and ultrasonic.

The usual way of detecting objects of varying shapes, heights, or positions has been through the use of an array of single-beam photoelectric sensors or a thru-beam light grid: a photoelectric array ...

Laser Proximity Sensors use laser beams to detect the presence or absence of objects within a certain range. They are used in security systems, robotics, automation, and industrial processes, where ...