{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T16:31:53Z","timestamp":1776357113040,"version":"3.51.2"},"reference-count":87,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,2,3]],"date-time":"2023-02-03T00:00:00Z","timestamp":1675382400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100007569","name":"Carl-Zeiss-Stiftung","doi-asserted-by":"publisher","award":["0563-2.8\/643\/2"],"award-info":[{"award-number":["0563-2.8\/643\/2"]}],"id":[{"id":"10.13039\/100007569","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Since the turn of the millennium, the development and commercial availability of optical frequency combs has led to a steadily increase of worldwide installed frequency combs and a growing interest in using them for industrial-related metrology applications. Especially, GPS-referenced frequency combs often serve as a \u201cself-calibrating\u201d length standard for laser wavelength calibration in many national metrology institutes with uncertainties better than u = 1 \u00d7 10\u221211. In this contribution, the application of a He-Ne laser source permanently disciplined to a GPS-referenced frequency comb for the interferometric measurements in a nanopositioning machine with a measuring volume of 200 mm \u00d7 200 mm \u00d7 25 mm (NPMM-200) is discussed. For this purpose, the frequency stability of the GPS-referenced comb is characterized by heterodyning with a diode laser referenced to an ultrastable cavity. Based on this comparison, an uncertainty of u = 9.2 \u00d7 10\u221212 (\u03c4 = 8 s, k = 2) for the GPS-referenced comb has been obtained. By stabilizing a tunable He-Ne source to a single comb line, the long-term frequency stability of the comb is transferred onto our gas lasers increasing their long-term stability by three orders of magnitude. Second, short-term fluctuations-related length measurement errors were reduced to a value that falls below the nominal resolving capabilities of our interferometers (\u0394L\/L = 2.9 \u00d7 10\u221211). Both measures make the influence of frequency distortions on the interferometric length measurement within the NPMM-200 negligible. Furthermore, this approach establishes a permanent link of interferometric length measurements to an atomic clock.<\/jats:p>","DOI":"10.3390\/s23031734","type":"journal-article","created":{"date-parts":[[2023,2,6]],"date-time":"2023-02-06T02:06:43Z","timestamp":1675649203000},"page":"1734","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["A GPS-Referenced Wavelength Standard for High-Precision Displacement Interferometry at \u03bb = 633 nm"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1398-8989","authenticated-orcid":false,"given":"Ulrike","family":"Blumr\u00f6der","sequence":"first","affiliation":[{"name":"Institute of Process Measurement and Sensor Technology, Technische Universit\u00e4t Ilmenau, 98693 Ilmenau, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paul","family":"K\u00f6chert","sequence":"additional","affiliation":[{"name":"Precision Engineering Division, Physikalisch Technische Bundesanstalt (PTB), 38116 Braunschweig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6060-7248","authenticated-orcid":false,"given":"Thomas","family":"Fr\u00f6hlich","sequence":"additional","affiliation":[{"name":"Institute of Process Measurement and Sensor Technology, Technische Universit\u00e4t Ilmenau, 98693 Ilmenau, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1832-7143","authenticated-orcid":false,"given":"Thomas","family":"Kissinger","sequence":"additional","affiliation":[{"name":"Institute of Process Measurement and Sensor Technology, Technische Universit\u00e4t Ilmenau, 98693 Ilmenau, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5611-7852","authenticated-orcid":false,"given":"Ingo","family":"Ortlepp","sequence":"additional","affiliation":[{"name":"Institute of Process Measurement and Sensor Technology, Technische Universit\u00e4t Ilmenau, 98693 Ilmenau, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jens","family":"Fl\u00fcgge","sequence":"additional","affiliation":[{"name":"Precision Engineering Division, Physikalisch Technische Bundesanstalt (PTB), 38116 Braunschweig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3137-924X","authenticated-orcid":false,"given":"Harald","family":"Bosse","sequence":"additional","affiliation":[{"name":"Precision Engineering Division, Physikalisch Technische Bundesanstalt (PTB), 38116 Braunschweig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1672-2978","authenticated-orcid":false,"given":"Eberhard","family":"Manske","sequence":"additional","affiliation":[{"name":"Institute of Process Measurement and Sensor Technology, Technische Universit\u00e4t Ilmenau, 98693 Ilmenau, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1279","DOI":"10.1103\/RevModPhys.78.1279","article-title":"Nobel Lecture: Defining and measuring optical frequencies","volume":"78","author":"Hall","year":"2006","journal-title":"Rev. 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