| 摘要 |
An optical system for endoscopes provided with a retrofocus type or two convex lenses type objective, a relay lens consisting of a graded refractive index lens for relaying an image of the objective and an eyepiece system for observing the image relayed by the relay lens, in order to make it possible to obtain a clear and high quality image of a wide visual field. The objective includes an aperture stop and a field stop provided between the objective and relay lens. The objective comprises a front lens group and rear lens group. The front lens group can be formed as of a straight viewing type, side viewing type or oblique viewing type. The rear lens group is movable along the optical axis through the relay lens.
|
