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More accurate angle measurement with CCD

PTB-News 3.2019
Especially interesting for

manufacturers of autocollimators

manufacturers of measuring instruments with CCD

To measure small angular changes in objects, autocollimators are used. The detector used for this purpose, often a two-dimensional CCD sensor, is illuminated by a linear reticle pattern. Its position on the sensor is detected and has a limited resolution due to the pixel size. In the new procedure, this reticle is projected onto the sensor at an angle set specifically for this sensor, relative to the pixel grid. Its position is then calculated by means of line-by-line averaging. The interpolation errors in the sub-pixel critical range of the sphere and thus hardly generates any parasitic reflection at all. Luminous flux can now be measured with far less distortion, which makes the transmission measurement considerably more accurate. (Technology Offer 475) ■ range are minimized and allow a better resolution of the position of the reticle᾽s image without additional components.

(Technology Offer 428)

Angle measurement using an autocollimator


reduces the measurement error without additional material needed

easy to integrate into existing measuring instruments

no special previous knowledge necessary

Contact person for questions about technology transfer

Andreas Barthel, Phone: +49 531 592-8307, Opens window for sending emailandreas.barthel(at)ptb.de, Opens external link in new windowwww.technologietransfer.ptb.de/en