We present methods for evaluation of the visual sparkle of antiglare treated surfaces and compare the results to visual ratings of expert observers. In addition we measure and characterize the reduction of image clarity induced by the scattering of microstructured AG-surfaces and the reduction of unwanted reflections achieved by the anti-glare layers.

The concept of the BRDF (Bidirectional Reflectance Distribution Function) is applied to analyze, characterize and understand the reflective properties of LCDs and their components in more detail. BRDFs are measured in the plane of light incidence with a goniometric apparatus ("inplane BRDF") while the full 2-dimensional BRDF is measured with a conoscopic device. BRDF-curves of typical reflective LCDs clearly show the individual contributions of the first surface (unwanted reflections) and the component from the reflector, which is modulated by the LC-cell and is thus carrying the information to be displayed. The effect of anti-glare coatings on the front polarizer surface is analyzed via BRDF measurements.Based on the acquired BRDF data we explain the function of a device for diffuse reflective illumination that can be considered as the correspondence to the "dark-room condition" in the case of transmissive LCDs since it is designed to effectively avoid disturbing unwanted reflections from the first display to air interface and, at the same time assuring illumination over a wide solid angle (up to 70°).

We introduce the combination of a high resolution RGB-camera with an array spectroradiometer for fast and accurate evaluation of lateral variations of chromaticity and luminance in the field of display metrology. The paper provides an analysis of the performance of this instrument when applied to colorimetric calibrations of state-of-the-art computer display screens under the timing constraints of manufacturing lines.

This contribution introduces a first implementation of the measurement setup according to IEC 62341-6-2 for evaluation of the effect of ambient illumination on OLED display contrast and chromaticity. A sampling sphere is providing hemispherical diffuse illumination, with and without specular components, in the d/8-geometry, and a point-light source is providing directional illumination. From the spectral reflectance factors thus obtained contrast and chromaticity for arbitrary illuminants (i.e. spectra) and illuminance levels can easily be calculated.

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