Parallelized chromatic confocal sensor systems

摘要

In this paper we present chromatic confocal distance sensors for the parallelized evaluation at several lateral positions. The multi-point measurements are performed using either one- or two-dimensional detector arrays. The first sensor combines the concepts of confocal matrix sensing and snapshot hyperspectral imaging to image a two-dimensional array of laterally separated points with one single shot. In contrast to chromatic confocal matrix sensors which use an RGB detector our system works independently from the spectral reflectivity of the surface under test and requires no object-specific calibration. Our discussion of this sensor principle is supported by experimental results. The second sensor is a multipoint line sensor aimed at high speed applications with frame rates of several thousand frames per second. To reach this evaluation speed a one-dimensional detector is employed. We use spectral multiplexing to transfer the information from different measurement points through a single fiber and evaluate the spectral distribution with a conventional spectrometer. The working principle of the second sensor type is demonstrated for the example of a three-point sensor.