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arXiv · 1812.06573

Innovative full-field chromatic confocal microscopy using multispectral sensors

Liang-Chia Chen·Pei-Ju Tan·Chih-Jer Lin·Duc Trung Nguyen·Yu-Shuan Chou·Nguyen Dinh Nguyen·Nguyen Thanh Trung
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Abstract

A full-field chromatic confocal microscopy using a multispectral sensor was developed for quasi-one-shot microscopic 3D surface measurement. An innovative optical configuration employs a digital micromirror device (DMD) and a multispectral sensor is used to realize chromatic confocal microscopy with full-field area scanning. In the optical design, an area-scan type chromatic dispersive objective is specially designed to achieve measuring specification. Based on an 8x chromatic dispersive objective, the FOV for one shot measurement can be reached to 1.8mm*1.3mm which is immersive to microscopic profilometry. The spectral image captured by the multispectral sensor at each pinhole position has a unique spectrum pattern corresponding to its conjugate measured depth. A normalized cross-correlation (NCC) algorithm is developed to establish a spectrum-depth response curve with its corresponding spectrum pattern sets for accurate reconstruction of the tested 3D surface profile. With real test on standard targets, the measurement repeatability for a single surface depth is less than 0.6 micrometer.

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Liang-Chia Chen, Pei-Ju Tan, Chih-Jer Lin, Duc Trung Nguyen, Yu-Shuan Chou, Nguyen Dinh Nguyen, Nguyen Thanh Trung. 2018-12-17. Innovative full-field chromatic confocal microscopy using multispectral sensors. https://arxiv.org/abs/1812.06573

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