A laser-based sensor is another option for detecting clear objects. A laser-based sensor operates with a laser instead of an LED, allowing for easier alignment, greater precision, detection of smaller objects, and detection of smaller gaps compared to an LED-based sensor. Some laser-based sensors, like the Q4X from Banner Engineering, also do not require a retro-reflector or receiving unit.
How Laser-Based Sensors Detect Clear Objects
In addition to measuring distance, laser sensors with dual mode capability can also detect changes in light intensity from a stable background condition. In other words, a laser distance sensor with dual mode can detect not only when the target is present within a certain distance but also when it returns a certain amount of light to the receiver.
For this to work, a stable reference surface must be taught, and the distance and intensity of the reference surface are recorded and used as a baseline. The presence of a transparent object entering the sensing range of the beam alters the perceived distance and light intensity from the background condition.
Laser-based sensors provide a highly visible laser spot for easy alignment, and a small laser spot ensures greater precision for detection of small objects. A laser-based sensor that does not require a reflector allows for more flexible mounting as well as reduced inventory and maintenance costs.