The measurement of optical components using Experimental Ray Tracing (ERT) has proven its abilities in numerous applications. In this paper, we show how the measurement speed can be boosted by using a position sensitive detector (PSD). The results are compared with the measurement results using a camera. The idea of ERT is based on the linear propagation of a beam’s centroid through a homogenous medium. Therewith, detecting the centroid position of a beam in two parallel planes with a known distance leads to the beams direction. By introducing narrow laser beams at known positions and directions into an optical component or system and measuring the direction of the beams behind the component or systems as described above, the optical function of the component or system can be determined. To get this measurement technique working accurately, we used a movable camera chip as detector in two parallel planes. This brings the advantage of a good linearity and repeatability of the centroid detection. However, in contrast with a PSD, a camera chip is slow due to the generation and processing of many unused data. A PSD can achieve a measurement rate 20 times faster than a camera chip. Although, a good calibration is needed to achieve the same linearity and repeatability as a camera chip. In this paper we show the advantages and disadvantages of the use of a camera chip and a PSD in ERT. By measuring the same optical component, the detectors characteristics can be compared.
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