加拿大外贸
镜头方面，请教！plano-convex or meniscus 具体是什么意思[ 本帖最后由 patty-chu 于 2010-10-26 16:43 编辑 ]
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no body
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google picture 。。。。。。
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googlr only show plano-convex.
难道是凹镜片和凸镜片的意思？
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plano-convex lens 凸透镜
Plano-Convex Lens that is positive (converging) spherical lens with one convex surface and one flat (plane) surface. These are most common type of lenses that are used for focusing, collecting and collimating light. Plano-convex lens are best suited at places, where one conjugate point (object distance or image distance) is more than five times the other. These optical lenses often used as simple imaging lens, where image quality requirement is not too critical. These lenses are usually offered to the clients at an economical price.
meniscus lens 凹透镜
meniscus (positive) lens that is shell-shaped, and has one convex and one concave surface. These lenses have a steeper convex surface and are thicker at the center than at the periphery. Designed in order to minimize spherical aberration, these lenses have a huge demand in the global market. When used in combination with another lens, a positive meniscus lens will shorten the focal length, and increase the na of the system. Further, these lenses are used to decrease the focal length of another lens, and maintain the angular resolution of the optical assembly.
[ 本帖最后由 vuwell 于 2010-10-26 16:31 编辑 ]
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