Micro-Epsilon extends its range of colour recognition sensors

LED testing

Benchtop multi-point measurement systems enable faster, easier inspection of light-emitting diodes (LEDs). The colorCONTROL MFA series starts with a basic version that offers five measuring channels. The colorCONTROL MFA-5 is very compact and can verify the colour, intensity and colour temperature (in Kelvin) of up to five LEDs simultaneously. The measuring system is modular and can be extended by adding extra MFA-E modules in batches of five channels, up to a maximum of four modules (ie 20 channels).

MFA sensors are suitable for a wide range of applications, including LED tests (binning), indication and displays, front panels, dashboard sequence tests and self-luminous object inspection. The MFA series can be used by manufacturers and developers of LED luminaires, including architectural and street lighting, and LED lighting for automotive interiors.

Fibre optics for close inspection

Micro-Epsilon's colorSENSOR LT range of sensors operate using optical fibres. The sensor is connected to an optical fibre that is guided to the measurement target. Colour detection therefore takes place very close to the object, which reduces any environmental effects that could adversely affect the measurement reliability. More than 2000 different types of fibre optic cable are available, as well as a large number of lenses. These provide customers with an almost unlimited number of combinations of sensor and optical fibre, which, in turn, enables Micro-Epsilon to help customers select the optimum colour recognition sensor for their application.

The colorSENSOR LT range includes low-cost, entry-level sensors through to high-precision, multi-channel colour recognition systems. The LT family offers measuring distances from 2-200mm and up to 255 colour memory locations. As well as exact colour, these memory options enable the user to store specific tolerance limits for different applications. During colour recognition inspection, the sensor compares the colour it has been taught with the colour currently detected. The results are then made available via digital interfaces (RS232 or USB) as discrete values/numbers or OK/NOK statements. The sensors are supplied with their own set up and configuration software and a graphical user interface that enables users to adjust the sensor to suit different applications.

Using new LED light sources, LT sensors can now be mounted much further away from the measurement target if required, at distances of up to 900mm.

Longer-range colour sensing

Micro-Epsilon's colorSENSOR OT series of colour recognition sensors operates by using fixed optical systems. These sensors are able to recognise the colour of objects from longer distances (from 2mm to 800mm). Different models are available to suit various surfaces and materials, including shiny, reflective and structured surfaces, as well as versions for recognising UV markings. OT sensors can even recognise colour variations along or between target objects and materials. This is particularly beneficial for manufacturers of vehicle interiors, leather, embossed film, fabrics, wood veneers and large painted components, where small colour variations are deemed unacceptable by customers.

OT sensors use nine white-light LEDs, whose brightness can be controlled as required. These LEDs are used as light sources for diffuse illumination. The switching status is displayed using five yellow LEDs. The sensors are insensitive to external light and have a true colour detector that filters XYZ values in a similar way to the human eye. However, a 'best hit' mode uses vector formation to show colours that are so similar that they are almost indistinguishable to the human eye. This provides customers with unambiguous, process-safe colour differentiation.

Easy set-up

All sensors in Micro-Epsilon's colorSENSOR range benefit from a 'teach-in' function that enables the sensor to learn and adapt to the application by using samples of the correct colour. Following this process, the sensor is able to compare the colour samples it has been taught with the target object, then operate independently.

High-speed colour measurement

Many applications require colours and shades to be examined on-the-fly and to very high accuracies. The colorCONTROL ACS7000 from Micro-Epsilon is an inline (in-process) high-speed colour measurement system that measures the actual colour of the target by identifying their co-ordinates in the colour space. The system identifies colours using any of the XYZ, L*a*b*, L*u*v*, RGB and DIN99 measurement definitions (user selectable). The system can be configured to monitor a production process continually and output the colour measurement via Ethernet, EtherCAT or RS422, and can also be taught pass fail/limits and then output out-of-tolerance alarms using digital I/O.

Existing applications for the colorCONTROL ACS7000 include automotive paint inspection, colour measurement of car interiors, coloured glass, transparent film and sheet production, printing, packaging, medical technology, food, cosmetics, pharmaceuticals and in the processing of plastics, food, wood, paper, veneer and textiles. The system is equally suitable for offline R&D laboratory applications.

Follow the link for more information about colour sensors from Micro-Epsilon.