Product portfolio
Laser differential sensors  – Differential, contrast and color sensors

Laser differential sensors

  • For monitoring position tolerances
  • Object detection on unsteady conveyor belts
  • Detection of min.-max. deviations in processes
  • Optional variant for step / edge detection
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Small laser contrast sensors

Small laser contrast sensors

  • Stong-focus laser beam for high-precision detection
  • Optional variant with linear laser beam to suppress material impurities
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Laser contrast sensors with an additional analog output

Laser contrast sensors with an additional analog output

  • Detection of gradual changes, e.g. in surface polishing
  • Short response time down to < 0.05 ms
  • Variants with current output
  • Strong-focus laser beam for high-precision detection
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White light contrast sensor

White light contrast sensor

  • For fast print mark detection
  • Cost-effective solution for print marks of all colors
  • Short response time down to < 0.05 ms
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Color sensors

Color sensors LOGIPAL®

  • Up to 4 color channels
  • Configurable color tolerance
  • Short response time 0.34 ms
  • Different spot sizes
  • PNP/NPN output
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Your benefits
  • Reliable detection
    • of the finest color shades - color sensor with up to 4 color channels
    • In artificial or changing lighting
    • at high speed - short response time of < 0.05 ms
    • of any position discrepancy thanks to differential sensors
  • Detection of very small objects
    • Detecting even tiny objects and surfaces by their difference in intensity
  • Space-saving installation
    • Very small contrast sensors in 10 mm design
    • Quick and convenient teach-in
    • Standardized teaching operations, optional potentiometer variants



Differential sensors
Precise and reliable object detection by fine laser beam and thanks to the sensor's outstanding color tolerance. Five different sensors variants with individual functionalities to optimally match the task.

Differential sensor with step evaluation
In step evaluation, objects are detected by their height difference (step) which is transferred int a digital output signal. The sensor evaluates the positive or negative height difference within a given time window of max. 5 ms. The difference exceeding the teached value by 50% will output a pulse of at least 10 ms. As soon as the value is inferior to 50%, the sensor goes back to OFF state. Where the height difference within the time window is below 50% of the teached limit (e.g. unsteady conveyor belt), the sensor remains in the OFF state.

  • Configuration of the step/edge limit in object detecion (minimum height 0.2 mm)
  • Defined output pulse of 10 ms (for read-in by standard PLC)
  • Detection of objects on unsteady conveyor belt
  • Step or edge detection
  • Object positioning by edge from any distance

Differential sensor with min./max. evaluation
With min./max. evaluation, object inspection and monitoring is by their scanned contour or shape. Object scanning is activated by an external control signal. At the end of the detection sequence, the detected measured values are evaluated and the difference between the minimum and maximum limit is determined. The difference exceeding the defined target is indicated as ON signal which remains active until starting a new detection sequence. Starting the next sequence will reset the output to OFF. If the difference is  below the target, the output remains in the OFF state.

  • Difference detection from any distance
  • User-configurable start and stop of the measuring cycle
  • Easy evaluation of good-bad signal 
  • Radial or lateral runout inspection at wheels / disks from any distance
  • Identificaton of misshaped plastic parts after cooling down

Differential sensor with tolerance evaluation
Tolerance evaluation is to check the dimensional stability of an object. In the continous detection of object distances, all detected values are verified to see if they are any above or below the specified tolerance. If so, an ON signal is provided at the output. If the distance remains within the specified tolerance the sensor remains in the OFF state.

  • Caliper in the form of a sensor
  • Easy distance monitoring within the tolerance range (good-bad information)
  • Individual teaching of tolerance and nominal distance
  • Checks on material thickness after the milling processl
  • Checks on material thickness at extruders

Differential sensor with tolerance evaluation
Tolerance evaluation allows for object classification based on a specified switching range. In doing so, the switching range is defined by teaching a maximum and minimum limit. An object being outside the limits will trigger an output signal.

  • Foreground and background suppression in one sensor
  • Individual teaching of several positions
  • Optional foreground or background suppression of interfering objects
  • Object detection on lamella-type conveyors

Differential sensor with 2-point comparison
In 2-point comparison, two distances measured at two selected points are compared against each other. A sync signal defines the point in time of the comparison. The first point is acquired at the positive sginal edge, the second at the negative signal edge. Once the second point has been acquired, the sensor evaluates the difference between the two points and compares it against the previously by teach-in defined maximum permissible deviation. Exceeding the tolerance will make the output go into ON state.

  • Comparirson of object heights from any distance
  • Teachable tolerances (min. 0.3 mm)
  • External signal for user-configurable point in time of the measuring operation
  • Verifcation of the press-in depth of bolts
  • Comparison of object  distance / height against a reference value

Technical and Application Reports / White Paper

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