Coherent and incoherent combination of Gaussian beams employing a lens array distributed on the spherical chamber is theoretically analyzed. The output field of each source in the array is coupled through an individual optical system whose local optical axis coincides with the radial direction of the chamber. The resulting intensity profile near the origin is derived. The intensity profile and power in the bucket on the target for rectangular and hexagonal arrangement are numerically calculated. The influences of the center-to-center separation and the ring number of the focusing lens array are given. The synthetic intensity profile of incoherent combination changes little for a lens array scale much smaller than the chamber size. In contrast, the synthetic intensity profile of coherent combination shows an interference pattern with a sharp central peak and sidelobes.
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http://dx.doi.org/10.1364/AO.51.001546 | DOI Listing |
Sensors (Basel)
January 2025
College of Geodesy and Geomatics, Shandong University of Science and Technology, Qingdao 266590, China.
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Sustainable Manufacturing Systems Centre, Faculty of Engineering and Applied Sciences, Cranfield University, Cranfield MK43 0AL, UK.
As urbanisation and infrastructure development continue to drive rising cement demand, the imperative to significantly reduce emissions from this emissions-intensive sector has become increasingly urgent, especially in the context of global climate goals such as achieving net zero emissions by 2050. This review examines the status, challenges and prospects of low-carbon cement technologies and mitigation strategies through the lens of the U.K.
View Article and Find Full Text PDFBiomark Res
January 2025
Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, Shanghai, 200032, China.
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January 2025
Department of Optometry, University of Benin, Benin City, Nigeria.
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January 2025
Institute of Modern Optics, Nankai University, Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Tianjin, 300350, China.
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