Measuring High Precision Color Measurements on Curved Surfaces

On curved or structured surfaces, traditional color sensors do not effectively provide accurate measurement results. Micro-Epsilon’s colorCONTROL ACS7000 inline color measurement system is particularly suitable for such tasks as it has a very small measurement spot size. It is considered to be one of the world’s most precise inline color measurement systems.

colorCONTROL ACS7000

The colorCONTROL ACS7000 inline color measurement system is used in many different fields. For instance, the highest requirements in the automotive industry must have zero defects. The colorCONTROL ACS7000 can easily measure structured surfaces in the car interior, such as the interior door trim, curved mirrors or cockpit surfaces, and bumpers or the B-pillar. Robot-controlled systems can also be used to detect contours.

Micro-Epsilon’s colorCONTROL inline color measurement system can also be used in the manufacture of the latest, popular personal communication devices. The system can recognize the latest colors and shapes of mobile phone designs, which are becoming more and more curvaceous, due its tiny measurement spot size.

The colorCONTROL inline color measurement system from Micro-Epsilon provides accurate measurement results on curved or structured surfaces, for example on fuel/tank caps.

The colorCONTROL inline color measurement system from Micro-Epsilon provides accurate measurement results on curved or structured surfaces, for example on fuel/tank caps.

Traditional measurement systems are not able to measure colors precisely because of the curvatures, however these measurements are achievable with the colorCONTROL system. Measurements can be carried out with the help of the continuous, homogeneous lighting, irrespective of the angular position of the measurement object.

The sensor with the designation ACS2-R45/0-28-1200(001) is designed as a circular sensor with a measurement spot of 3 x 2 mm. This is the reason why the new sensor head is perfectly suitable for the quality control of curved objects. The curvature radius should be at least 20 mm.

colorCONTROL ACS2 recognizes colors and shapes of mobile phone covers

colorCONTROL ACS2 recognizes colors and shapes of mobile phone covers

Structured and highly reflective surfaces and lustrous metals can be measured using the ACS2 circular sensor. Twenty-four lighting optics, arranged in a circular fashion around the receiving optics, provide uninterrupted lighting. This lighting allows measurements to be taken irrespective of the angular position of the measurement object.

The colorCONTROL ACS7000 inline color measurement system recognizes colors by comparing them to reference values as well as by using their coordinates in the respective color space to ensure unique identification. In applications where colors and shades need to be inspected on-the-fly and to very high accuracies, the colorCONTROL ACS7000 is suitable as it has very high measurement speeds.

The color measurement also ensures the production of correct color in the desired quality. The system’s high measurement accuracy makes it suitable for laboratory operations and the production of plastics and textiles. Wooden veneers, textiles, and floor coverings can also be easily inspected.

Measuring Principle

The most accurate method of color measurement is the spectral procedure. Initially, a homogeneous white LED light is used to illuminate the sample. A white reference is then used to calculate the spectrum of the reflected light. Subsequently, the coordinates in the CIE-XYZ color system are measured for all wavelengths of visible light (390 to 780 nm) and output in the desired color space.

Different observation conditions such as the type of light (illuminant) and standard observer are considered by the controller. The colorCONTROL ACS7000 comes with three operating modes: in the first mode, the system measures the color difference (ΔE) from the taught-in reference value. The system can be operated with up to 15 taught values.

In the second operating mode, the reflectivity spectrum of the sample is determined and displayed. In the third mode, color coordinates are determined and displayed in the desired color space.

A trend analysis can be performed for quality inspection purposes over any time period via L*a*b*; XYZ or L*c*h color values. Measurement speeds up to 2 kHz are supported in all three operating modes.

The ACS1 standard sensor is used for common measuring tasks, for example, in the manufacture of high quality material strips and boards from titanium zinc where the surfaces are subjected to specific heat treatment. Therefore, during the production process, it is possible to determine the coloring of the zinc products beforehand.

Constant product quality is ensured by the highly precise and fast color measurement system. The transmitter and the receiver present inside the sensor are arranged at an angle of 30°/0° or 45°/0° to each other, providing a working distance of 50 mm or 38 mm.

Using the 30°/0° sensor in tactile measurements is enabled by using an optionally available adapter. To measure self-luminous objects and transparent objects such as glass, film, and Plexiglas®, the ACS3 transmission sensor can be used. Additionally, the color of self-luminous objects can also be detected, for which only the receiver unit is needed. A transmitter (TT) and receiver unit (TR) can be easily installed using a mounting set to measure transparent objects.

colorCONTROL ACS7000 is one of the most advanced inline color measurement systems in the world. Different sensor models are available to suit various measurement tasks.

colorCONTROL ACS7000 is one of the most advanced inline color measurement systems in the world. Different sensor models are available to suit various measurement tasks.

This information has been sourced, reviewed and adapted from materials provided by Micro Epsilon.

For more information on this source, please visit Micro Epsilon.

Ask A Question

Do you have a question you'd like to ask regarding this article?

Leave your feedback
Submit