Abstract
We present a high-speed double-slit interferometer (HS-DSI) for in-line thickness measurement of large-sized glass panels. Because the HS-DSI has a differential and common-path configuration, it is robust to external disturbance and vibration of glass panels. For the in-line measurement, the interferometer employs a position sensitive detector (PSD) to detect an interference fringe shift with high speed, which corresponds to the differential thickness variation. We present the method and the results of theoretical analysis on the performance of the HS-DSI in respect of sensitivity and nonlinearity error to determine the optimal design parameter values, and the optimal design strategy. A calibration method using a cylindrical lens is also proposed. In the comparison with an interferometric thickness measurement system, the deviations were less than 70 nm and 15 nm for thickness profiles and their waviness components, respectively. When a glass plate was translated with speed of 300 mm/s, the measurement repeatability was less than 0.4 nm for the waviness component of the thickness profile.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
ISO 428., “Geometrical Product Specifications (GPS) — Surface Texture: Profile Method — Terms, Definitions and Surface Texture Parameters,” 1997.
Lapp, J. C., “AMLCD Substrates Trends In Technology,” http://www.corning.com/media/worldwide/cdt/documents/TIP_102.pdf (Accessed 6 JUL 2015)
Räsänen, J. and Peiponen, K.-E., “On-Line Measurement of the Thickness and Optical Quality of Float Glass with a Sensor based on a Diffractive Element,” Applied Optics, Vol. 40, No. 28, pp. 5034–5039, 2001.
Hibino, K., Oreb, B. F., Fairman, P. S., and Burke, J., “Simultaneous Measurement of Surface Shape and Variation in Optical Thickness of a Transparent Parallel Plate in Wavelength-Scanning Fizeau Interferometer,” Applied Optics, Vol. 43, No. 6, pp. 1241–1249, 2004.
Kim, S., Na, J., Kim, M. J., and Lee, B. H., “Simultaneous Measurement of Refractive Index and Thickness by Combining Low-Coherence Interferometry and Confocal Optics,” Optics Express, Vol. 16, No. 8, pp. 5516–5526, 2008.
Protopopov, V. V., Cho, S., Kim, K., Lee, S., Kim, H., and Kim, D., “Heterodyne Double-Channel Polarimeter for Mapping Birefringence and Thickness of Flat Glass Panels,” Review of Scientific Instruments, Vol. 77, No. 5, Paper No. 053107, 2006.
Protopopov, V., Cho, S., Kim, K., Lee, S., and Kim, H., “Differential Heterodyne Interferometer for Measuring Thickness of Glass Panels,” Review of Scientific Instruments, Vol. 78, No. 7, Paper No. 076101, 2007.
Liu, C.-H., and Li, Z.-H., “Application of the Astigmatic Method to the Thickness Measurement of Glass Substrates,” Applied Optics, Vol. 47, No. 21, pp. 3968–3972, 2008.
Kim, J.-A., Kang, C.-S., Eom, T. B., Jin, J., Suh, H. S., and Kim, J. W., “Quadrature Laser Interferometer for In-Line Thickness Measurement of Glass Panels using a Current Modulation Technique,” Applied Optics, Vol. 53, No. 20, pp. 4604–4610, 2014.
Kim, J.-A., Kim, J. W., Eom, T. B., Jin, J., and Kang, C.-S., “Vibration-Insensitive Measurement of Thickness Variation of Glass Panels using Double-Slit Interferometry,” Optics Express, Vol. 22, No. 6, pp. 6486–6494, 2014.
Hamamats., “Characteristic and Use,” https://www.hamamatsu.com/resources/pdf/ssd/psd_techinfo_e.pdf (Accessed 6 JUL 2015)
ISO 1661., “Geometrical Product Specifications (GPS) — Filtration — Part 21: Linear Profile Filters: Gaussian Filters,” 2011.
Godina, A., Acko, B., and Druzovec, M., “New Approach to Uncertainty Evaluation in the Calibration of Gauge Block Comparators,” Measurement, Vol. 40, No. 6, pp. 607–614, 2007.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Kim, JA., Kim, J.W., Kang, CS. et al. High-speed double-slit interferometer using a position sensitive detector for in-line thickness variation measurement of glass panels. Int. J. Precis. Eng. Manuf. 16, 1955–1961 (2015). https://doi.org/10.1007/s12541-015-0254-3
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12541-015-0254-3