| 摘要 |
<p>An optical system for an endoscope is configured in such a manner that, despite the fact that the direction of the field of view is made variable, the tip of the endoscope has a small diameter and an endoscope image having good image quality is obtained. An optical system for an endoscope is provided with: a first prism (11) for deflecting and emitting light, which enters along the incident light axis, in the direction of a first axis (A) perpendicular to the incident light axis; a second prism (12) provided with two reflective surfaces (12b) for bending back the light, which is emitted from the first prism (11), along a second axis (B) spaced from the first axis (A); a third prism (13) for deflecting the light, which is bent back by the second prism (12), in the direction along a plane perpendicular to the first axis (A) and containing the incident light axis. The first prism (11) is provided so as to be pivotable about the first axis (A) relative to the second prism (12), and the two reflective surfaces (12b) of the second prism (12) are arranged so as to form an obtuse angle relative to each other.</p> |
