| 摘要 |
<p>A telecentric image-forming optical system comprises: a first lens group including a double-convex lens (r1, r2), a meniscus lens (r3, r4) whose convex side faces an object or a plano-convex lens, and a double-concave lens (r5, r6) arranged in this order; and a second lens group including a double-convex lens (r13, r14), a meniscus lens (r11, r12) whose convex side faces an image or a plano-convex lens, and a double-concave lens (r9, r10) arranged in this order. The secondary focal point of the first lens group and the principal focal point of the second lens group substantially coincide in the vicinity of a double-convex lens (r7, r8). The telecentric image-forming optical system is compact and forms a large-sized image for its optical length.</p> |
