The light output inspection process of cathode ray tubes, flat panels and other displays often requires extremely precise and time-consuming manual steps. This paper describes the PR-900 Video Photometer, a PC-based photometric, spatial and colorimetric instrument which automates this inspeCtion process - eliminating operator error and greatly reducing measurement time. The PR-900 digitizes the displayed image as acquired in video form and converts the data into an accurate NBS-traceable measurement. The IBM PC/AT-based photometer is designed for speed and resolution. The system includes a personal computer, an image digitizer, a customized CCD-array Video Sensor Assembly (VSA), interwhangeable objective lenses and proprietary VideoView software. Optionally, an automatic VSA Positioning Stage is added for Automatic Test Environment (ATE) applications. With its modular approach, the hardware and software of the video photometer is readily optimized to meet diverse measurement requirements. This versatile instrument is used to calculate such a wide scope of parameters as luminance (brightness) uniformity, line width, luminance profiles, character size, spot contours, modulation transfer function (MTF), misconvergence, geometric distortion and relative chromaticity (color) coordinates.
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