| 摘要 |
A secondary flat mirror (8) is provided at the middle of a transparent glass plate (7) provided at the end of an adjustable case unit (4) attached to a tube case (1) with a threaded portion (5) in a case end (6). A movable ocular (3) is attached from the external to an eyepiece lens (17) provided in the tube case. A positive extension piece (10) inside the tube case is attached to the cover (13) of the tube case. The positive extension piece is provided with achromatic lenses (11,12). A primary mirror (14) is provided under the positive extension piece and centered with an opening (15) with optical axis at the middle. |
