| 摘要 |
PURPOSE:To permit easy assembly by providing an annular part having the same radius of curvature as the radius of curvature of the other end of two adjacent lenses to the peripheral part of one of the opposed faces of said lenses and adhering the lenses by means of an adhesive agent in such a way that the optical axes thereof coincide with each other. CONSTITUTION:An annular joint surface 2c for a concave lens 2 is provided to the peripheral part of the face of a convex lens 1 facing the lens 2 and the radius of curvature of 2c is made equal to the radius of curvature of the lens 1. A similar annular joint surface 2d is also provided between the lens 2 and a convex lens 3 and the radius of curvature thereof is made equal to the radius of curvature of the lens 3. The respective joint surfaces 2c, 2d are adhered by the adhesive agent so as to align the centers of the six curvatures on both faces of the lenses 1-3. The lens groups 1-3 combined in the above-mentioned way are fixed to a lens barrel 7 by a retaining ring 8. The need for fitting exactly and separately the respective lenses to the lens barrel is thus eliminated and the assembly is made easy. |
