The Benefits
Reliable detection of labels of a wide range of materials h3>
Quick and easy sensor configuration h3>
Precise label recognition even at high conveyor speeds h3>
Product Portfolio Label Sensors
Functional Principles of Label Sensors
An optical label sensor works with infrared light. An emitter and a receiver form a forked sensor, with the receiver measuring the light intensity. When passing through a label, light is partially absorbed or scattered. This makes it possible to distinguish reliably between the label material and the label.
With ultrasound-based recognition, a sensor emits ultrasonic waves, which are evaluated by the receiver. The signal changes due to different sound attenuation of the materials. This technology is particularly suitable for metalized films and transparent and paper labels.
Application Examples for Label Recognition
Glossy Label on Label Material
Challenge: Glossy labels create strong reflections, reflecting back the light emitted by the sensor.
Solution:
Ultrasonic fork sensors detect labels regardless of color, transparency or surface finish. Glossy materials are not a challenge.
Reflex gloss sensors can be used if there is sufficient difference in gloss between the label and the label material.
High Contrast Between Label and Label Material
Challenge: Labels and label material often differ significantly in color or brightness. These contrast differences must be reliably detected even at high line speeds and changing material batches.
Solution:
Optical label sensors detect even slight changes in light intensity and enable reliable label detection.
Ultrasonic label sensors detect labels regardless of color and contrast based on different sound attenuation.
Contrast, color and gloss sensors enable precise detection of differences in brightness, color and surface.
Low Contrast Differences Between Label and Label Material
Challenge: The optical properties of the label and the label material are almost identical. Small differences in reflection and light transmission make it difficult to reliably detect the edge of the label.
Solution:
Ultrasonic label sensors detect labels regardless of their optical properties based on the different sound attenuation between the label and the label material.
Optical label sensors detect even the smallest changes in the received light signal and enable reliable detection.
Selection Aid for Choosing the Right Sensor for Every Label Application
| Label | Contrasting | Glossy/metal | Transparent | Luminescent | Colored | |
| Label medium | Bright | Bright | Transparent/bright | Bright | Bright | |
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Label fork (optical) | |||||
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Label fork (ultrasound) | |||||
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Fiber-optic sensors | |||||
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Color sensors | |||||
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Luminescence sensors |
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Label
Label medium
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Contrasting
Bright
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Glossy/metal
Bright
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Transparent
Transparent/bright
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Luminescent
Bright
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Colored
Bright
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Label
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Contrasting
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Glossy/metal
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Transparent
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Luminescent
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Colored
|
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Label
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Contrasting
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Glossy/metal
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Transparent
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Luminescent
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Colored
|
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Label
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Contrasting
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Glossy/metal
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Transparent
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Luminescent
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Colored
|
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Label
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Contrasting
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Glossy/metal
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Transparent
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Luminescent
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Colored
|
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Label
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Contrasting
|
Glossy/metal
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Transparent
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Luminescent
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Colored
|
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Label
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Contrasting
|
Glossy/metal
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Transparent
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Luminescent
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Colored
|
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Label
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Contrasting
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Glossy/metal
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Transparent
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Luminescent
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Colored
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