A Fresnel lens is a type of composite compact lens developed by the French physicist Augustin-Jean Fresnel (1788–1827) for use in lighthouses.It has been called "the invention that saved a million ships. The design allows the construction of lenses of large aperture and short focal length without ... Read More
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MANUFACTURING FRESNEL LENSES The first Fresnel lenses were made by tediously grinding and polishing glass by hand. Eventually, molten glass was poured into molds, but it was only with the development of optical-quality plastics and injection-molding technology in the 20th-century that the use of ... Read More
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A passive infrared sensor (PIR sensor) is an electronic sensor that measures infrared (IR) light radiating from objects in its field of view. They are most often used in PIR-based motion detectors. PIR sensors are commonly used in security alarms and automatic lighting applications. Read More
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A Fresnel lens is a type of composite compact lens developed by the French physicist Augustin-Jean Fresnel (1788–1827) for use in lighthouses.It has been called "the invention that saved a million ships. The design allows the construction of lenses of large aperture and short focal length without ... Read More
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Theory | Manufacturing | Applications Fresnel lenses consist of a series of concentric grooves etched into plastic. Their thin, lightweight construction, availability in small as well as large sizes, and excellent light gathering ability make them useful in a variety of applications. Fresnel lenses ... Read More
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