DEVICE FOR ADJUSTING OPTICAL AXIS

摘要

PURPOSE:To make the adjustment of a slight directional angle with a simple construction possible by providing a deflecting material having the deflection angle varying according to the incident position of a light beam so as to be made movable in the direction intersecting orthogonally with the optical axis of an optical system. CONSTITUTION:The light beam emitted from a light projecting element 22 and collimated by a lens system 23 is deflected in the optical axis thereof in a vertical direction by a prism 1. The deflection angle beta changes as well as the vertical angle alpha of the part where the light beam passes changes when the prism 1 is moved in the direction of the ridge 1a thereof. The optional deflection angle is therefore obtd. according to the position of the prism 1. The optical axis of the light beam is similarly deflected in the horizontal direc tion by another prism 2 and the deflection angle thereof changes with the move ment of the prism 2. The prisms 1 and 2 are freely independently movable from each other and therefore the adjustment of the optical axis of the exit light beam in an optional direction as much as an optional angle is therefore possible. The optical axis adjustment is thus made possible by the mere opera tion of moving the prisms 1, 2.