| 摘要 |
Objective lenses for endoscopes are made substantially of sapphire. The high refractive index of sapphire results in optical components with shallower curvatures, leading to smaller geometric aberrations, and consequently fewer components are required to correct for these aberrations, Chromatic aberrations are less severe because of sapphire's low dispersion. The objectives may be either of the landscape or retrofocus type, and are compact with moderate field of view, low f-number, and less distortion than most conventional designs.
|
