Multiwavelength digital holography with meter scale synthetic wavelengths at micrometer precision

Tobias Seyler; Jens Kiessling; Markus Fratz; Annelie Schiller; Jonas Stevanovic; Alexander Bertz; Daniel Carl

doi:10.1117/12.2621641

20 May 2022 Multiwavelength digital holography with meter scale synthetic wavelengths at micrometer precision

Tobias Seyler, Jens Kiessling, Markus Fratz, Annelie Schiller, Jonas Stevanovic, Alexander Bertz, Daniel Carl

Proceedings Volume 12137, Optics and Photonics for Advanced Dimensional Metrology II; 121370R (2022) https://doi.org/10.1117/12.2621641
Event: SPIE Photonics Europe, 2022, Strasbourg, France

Conference Poster

Abstract

Digital holography enables high-precision quality control in machining production and has already been introduced to several multi-axis systems1, 2. To meet the demanding measurement tasks in the quality control of complex components, accuracies in the sub-micrometer range with measurement ranges larger than several centimeters are required. Previous measurements have shown the potential of multiwavelength digital holography to allow unambiguous ranges of few millimeters3 . We present multiwavelength digital holographic measurements using synthetic wavelengths with two meters down to a few micrometers, potentially enabling measurements with meter-scale unambiguity at sub-micrometer accuracy. Measurements on a 10 cm step-height sample have been conducted using the compact digital-holographic sensor HoloTop NX for various multi-axis systems, supplied by an Ondax LMFC single frequency diode laser at 632.852 nm and the tunable laser Hübner C-Wave used in the wavelength range of 480.786 nm – 632.852 nm. The latter offers a frequency stability of 150 MHz on a time scale of several hours. The maximum laser drift during data acquisition was observed to be 0.02 pm. Thus, at the 2 m synthetic wavelength, this results in a maximum synthetic wavelength error of 200 mm. Random noise of 20 mm at the largest used synthetic wavelength of 2 m requires multiple synthetic wavelengths to get down to micrometer precision: Eight nested synthetic wavelengths from 2 µm to 2 m and numerical refocusing of the hologram were used to evaluate a milled sample with multiple step heights, machined on a Hermle C32U machine tool. Ten repetitive measurements confirm a machining uncertainty of 9 µm for this sample at its maximum step height of 10 cm.

Citation Download Citation

Tobias Seyler, Jens Kiessling, Markus Fratz, Annelie Schiller, Jonas Stevanovic, Alexander Bertz, and Daniel Carl "Multiwavelength digital holography with meter scale synthetic wavelengths at micrometer precision", Proc. SPIE 12137, Optics and Photonics for Advanced Dimensional Metrology II, 121370R (20 May 2022); https://doi.org/10.1117/12.2621641

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available