Glare Sensor - Redefining polished performance

Nov 24, 2014
Waldkirch/Nuremberg, November 2014

For Contrast, Color, Luminescence the glossiness is an optical property of objects which cause failures. As a result of this, for most sensors shiny objects are difficult to detect. The GLARE Sensor turns this failure into a function! The GLARE sensor detects define gloss levels or differentiate between gloss levels.

The Glare sensor is specially designed to recognize and differentiate objects on the basis of their gloss in order to control production processes. The Glare sensor analyzes the spatial distribution of reflected light using Delta-S technology, which allows the sensor to determine the gloss level of flat object surfaces and to differentiate between objects of differing gloss levels. The measurement result is transmitted to the process controls either via two digital switching outputs or IO-Link.Several operating modes are available, making the Glare sensor perfectly suited to a range of different applications. The combination of intelligent signal evaluation algorithms, the multi-sensor arrangement and sensitivity adjustments ensure increased operational safety in industrial applications. The Glare’s IO-Link interface enables the sensor to be integrated into the machine controller, featuring automatic, process-oriented configuration and online diagnostics.

GLARE offers a non-contact process for measuring and reliably assessing the gloss properties of different materials and surfaces regardless of color, transparency or pattern. In general terms, the optical property of 'gloss' in this context describes the relationship between light that is refracted non-directionally and that which is directionally reflected. When detecting transparent safety labels, the sensor distinguishes with maximum reliability between high-energy directed reflection from the plastic surface of the label and the scattered, diffuse reflections from the rougher surface of the packaging material. In contrast to gloss measuring devices, the GLARE gloss sensor is not only significantly more economical and simpler to integrate from a process technology viewpoint – it can also be used without reference to norms for the purpose of measuring high, medium and low gloss in reflectometric terms. The reading is a measurement not of the gloss level in GU ('gloss units') but of the change in gloss level as given by two digital switching outputs.

Gloss – a property which often interferes with sensor function – is for GLARE an advantageous characteristic of the object or surface that can be enormously useful. For a number of tasks where detection by means of color or contrast criteria is not possible, the gloss sensor with its Delta-S technology provides a reliable detection option. GLARE has a scanning range of 50 mm and uses two receiver fields and eight transmitter axes. The red LEDs transmit in various directions and create a light spot size of approximately 10 mm x 13 mm. This arrangement renders the sensor invulnerable to vibrations during machine operation and to any wobbling of the objects as they pass the sensor and thus ensures reliable detection of gloss changes between label and pack. "For us as machine engineers, it is also important that GLARE should not require time-consuming configuration, or need additional illumination or protection against ambient light," says Daniel Sanwald, referring to the ease with which the gloss sensor can be integrated into a system. During operation, GLARE distinguishes between directional and diffuse reflections, using an intelligent algorithm to evaluate the received signal in terms of its spatial distribution. By simultaneously observing the dynamic transitions between gloss states, GLARE also achieves good signal quality.

IO-Link option offers powerful benefits
GLARE can optionally be integrated into the machine controller by means of an IO-Link. This allows the sensor to be adjusted via the controller and a wide range of process data to be supplied during operation; this data can then be processed for specific purposes in the PLC or at the user interface. As required in a pharma environment, the configuration data is stored centrally in the machine controller.
GLARE opens up a range of interesting applications such as the monitoring of damp oil, adhesive or paint coatings in automobile production, the monitoring of smoothing, cleaning and polishing processes, the detection of glossy or transparent packaging in food and drink technology, the monitoring of glue applications in wood and furniture production, and the checking of coatings on assemblies and layers in the construction of solar panels and flat-screen monitors.