| 摘要 |
PURPOSE:To obtain a bright ocular lens improved at the flatness of an image surface by constituting the ocular lens of the 1st and 2nd positive lens groups arranged successively from the image side and constituting the lens system with prescribed conditions. CONSTITUTION:The 1st lens group is constituted by adhering the 1st positive lens turning its large curvature side to the eye side, the 2nd negative lens having concave surfaces on both the sides and the 3rd positive lens having convex surfaces on both the sides. The optical system is satisfied with various conditions in equations I-VII. In the equations, ni is the refractive index of the i-th lens, nui is the Abee's number of the i-th lens, (f) is a focal distance, the ri is the radius of curvature of the i-th surface.
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