| 摘要 |
A cylindrical covering cap for an eyepiece tube, the eyepiece tube having a conical soft eyecup, includes, in a cylindrical interior of the covering cap: two mutually opposite segment regions having a segment region inside radius that is greater than an inner aperture radius of the covering cap; and at least two mutually opposite segment surfaces, which may be circumferentially spaced so that the locations of the segment surfaces are approximately symmetric about a segment region axis that passes through a center of each of the segment regions. A shortest distance from each segment surface to a cylinder axis may be smaller than the inner aperture radius of the covering cap, and the inner aperture radius of the covering cap may be configured to adapt to a larger outside radius of the conical eyecup. The segment surfaces may be substantially flat or have a substantially cylindrical curvature.
|
