| 摘要 |
FIELD: optics.SUBSTANCE: eyepiece comprises, in order from an object, a first positive lens a second negative lens and a third positive lens. Surface of first lens on object side has a convex shape, surface of second lens on observation side has a concave shape, and following expressions are satisfied: 0.65 < f11/f < 1.00; -0.75 < f22/f < -0.30 and -100,00 < (r2b+r1a)/(r2b-r1a) < -5.00, where f is focal distance of eyepiece, F11 is focal distance of surface of first lens on object side, F22 is focal distance of surface of second lens on observation side, R1A is radius of curvature of surface of first lens on object side and r2b is radius of curvature of surface of second lens on observation side.EFFECT: technical result is increase in distance from display surface to surface of first lens during high magnification.8 cl, 13 dwg, 1 tbl |
