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A sinusoidal phase modulating absolute distance measurement (ADM) interferometer combining frequency-sweeping interferometry (FSI) and multi-wavelength interferometry (MWI) is proposed in this paper. The swept frequency in FSI and the wavelengths for MWI are calibrated by an optical frequency comb, so the distance measurement can be directly traced back to the SI definition of a meter. With a simple optical structure, an ADM interferometer consisting of a measurement interferometer and a monitor interferometer is constructed without polarization optics. A near-infrared external cavity diode laser (ECDL) calibrated by an optical frequency comb is used as a work source of the measurement interferometer for frequency sweeping and hopping. The monitor interferometer using a He-Ne laser runs parallel to the measurement interferometer to monitor the fluctuation of the measured distance during the measurement. Experiments for absolute distance measurements in a range of 8.25 m were carried out to verify the feasibility of the proposed ADM interferometer. The experimental results show that the maximum measurement error is less than 1 μm compared with an incremental-type laser interferometer.
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http://dx.doi.org/10.1364/OE.26.009273 | DOI Listing |
Am J Biol Anthropol
September 2025
Magyar Gyula Horticultural, Technical and Vocational Training School, Budapest, Hungary.
Objectives: This study explores cranial morphological variation and population continuity in the Carpathian Basin from the 1st to 13th centuries CE. It focuses on assessing biological differences and similarities across major archaeological periods, with particular emphasis on the Avar, Hungarian Conquest, and Árpádian Age populations.
Materials And Methods: A total of 1,597 adult crania (864 males, 733 females) were analyzed using six neurocranial measurements.
J Appl Stat
February 2025
Faculty of Pure and Applied Mathematics, Wrocław University of Science and Technology, Wrocław, Poland.
Inequality (concentration) curves such as Lorenz, Bonferroni, Zenga curves, as well as a new inequality curve - the curve, are broadly used to analyse inequalities in wealth and income distribution in certain populations. Quantile versions of these inequality curves are more robust to outliers. We discuss several parametric estimators of quantile versions of the Zenga and curves.
View Article and Find Full Text PDFClin Ophthalmol
September 2025
Università degli studi di Milano, Milan, Italy.
Purpose: To report clinical outcomes in patients implanted with an isofocal optic-design intraocular lens (IOL) with double C-loop haptics following cataract surgery.
Methods: This was a multicentre-prospective-study involving 108 eyes (54 subjects) implanted with the Isopure Serenity (BVI, Inc). IOL.
Biophys J
September 2025
Biophysical and Biomedical Measurement Group, Microsystems and Nanotechnology Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, USA. Electronic address:
Macromolecular structure is central to biology. Yet, not all biomolecules have a well-defined fold. Intrinsically disordered regions are ubiquitous, conveying a versatility to function even in otherwise folded structures.
View Article and Find Full Text PDFArch Public Health
September 2025
Centre for Clinical Research, Region Värmland, Karlstad, 651 85, Sweden.
Background: Physical inactivity, impaired physical mobility and poor mental health are common in the older population and increasing as the population ages. We examined the relationships between physical activity, physical mobility, and mental health in the general population of older adults.
Methods: The study is based on 12 959 men and women aged 70 years or older answering a survey questionnaire sent to a random population sample in Mid-Sweden in 2022 (response rate 66%).