Sipke Wadman

9.3: The Use of an Imaging Sphere for High‐Throughput Measurements of Display Performance — Technical Challenges and Mathematical Solutions

For display metrology, two of the most important parameters are brightness and color as a function of angle. Here we describe a new technique based on an imaging sphere, featuring optomechanical simplicity and high data acquisition rates, compared to traditional techniques. We also show how raw data is converted into parametric information, illustrated with real test data.

Appearance characterization by a scatterometer employing a hemispherical screen

Characterization of optical appearance by measurement of the hemispherical scattering distribution using a concave projection screen and a camera is investigated. Secondary intensities by repeated internal screen reflections can be measured separately and compensated for. The concept is coupled to functional properties of product surfaces and we use it in an industrial environment. Only little less accurate than a photogoniometer, the hardware is much cheaper, contains no moving parts and is up to 1000 times faster.

Laser and materials technology for flexible decoration in mass production

Customization of products is an important factor in selling products. This will lead to an increasing number of types in the production. To control this, a flexible way of decoration should be integrated in the production. Without a flexible and high yield mass customization method, the integration of customization in a mass production cannot be achieved. Laser decoration is one of the possible techniques that is able to meet the demands for flexibility and high yield. There are already some methods available, but the combination of quality with price is, at the moment, an obstacle. Laser decoration is the only technique which is already integrated into a mass production environment and is able to join decorative marking with high yield and low costs. Color flexibility is, however, still a major challenge for laser decoration. In order to expand towards a more mature technique and to explain the necessary developments, we would like to focus on the process. The process is a combination of laser technology, material technology and software (decoration, engraving, marking, tunable lasers, multi color, process control).