Optical: systems and elements – Compound lens system – Telescope
Patent
1991-01-09
1992-08-11
Gonzalez, Frank
Optical: systems and elements
Compound lens system
Telescope
359744, 359831, 359894, G02B 2504, G02B 2302
Patent
active
051384876
ABSTRACT:
A door viewer includes two prisms of rectangular isosceles triangle shape in cross section whose hypotenuse surface abut horizontally, a front convex lens and a plano-convex eyepiece lens. The front convex lens has a front concave surface and a rear convex surface to correct chromatic aberration. The convex surfaces of the front and eyepiece lens are positioned face to face with each other to correct barrel distortion. The view casts an image onto a ground glass section formed on or provided abutting the eyepiece lens.
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Gonzalez Frank
Han Seung H.
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