Optical level sensors

Optical level sensors are devices used to detect the presence or absence of a liquid at a specific point within a container, tank, or vessel. These sensors operate using the principles of light transmission and reflection, making them highly reliable for a wide range of applications where accurate and maintenance-free level detection is required.

optical level sensors use light and reflection

Level sensors – Optical – ALP Industry

  • High media compatibility
  • Compact design
  • High temperature devices available

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Level sensors – Optical – ALP Digital

  • High media compatibility
  • Compact design
  • High temperature devices available

More information »

How optical level sensors work

Optical level sensors typically consist of an infrared LED and a photodetector. The basic working principle involves the interaction of light with the liquid being monitored:

  • Light transmission: The infrared LED emits light into a prism or a small glass or plastic probe that is part of the sensor.
  • Light reflection: In the absence of liquid, the light reflects off the internal surfaces of the prism and returns to the photodetector. When the liquid reaches the sensor and immerses the probe, the light is refracted into the liquid rather than reflected back to the detector.
  • Detection: The change in the amount of light reaching the photodetector indicates the presence or absence of the liquid. This signal can then be used to trigger alarms, switches, or other control mechanisms.
women operating gages at a tank that run with optical level sensors

High-precision
sensors

Highest precision for lowest pressures, reliable MEMS pressure sensors.

Innovative
technologies

Innovative CoBeam²™ technology and dual die technology.

Customised
system solutions

Individual system solutions for perfect integration of measurement technology in sophisticated applications.

Comprehensive
product range

Standard solutions on a modular product platform.