| 摘要 |
PURPOSE:To improve the reproducibility of mirror angles by sucking and driving a shaft mounted with a mirror at its leading end by means of stators and further supporting both end parts of the shaft freely slidably by means of bearings. CONSTITUTION:The movement in A, B directions of a shaft 12 mounted with a mirror 11 at its leading end is accomplished as the supporting parts 12a, 12a' of the shaft 12 are supported by the bearings 3, 3' disposed to stators 5, 5', wherein the shaft 12, hence the mirror 11, is moved without causing circumferential whirling by the engagement of the guide surfaces 12b, 12b, 12b', 12b' of the parts 12a, 12a' and the bearing elements 3b, 3b' of the bearings 3, 3', and in the projected state and the retreated state, it is surely circumferentially located by tapered guides 9b, 9b', 10b, 10b', whereby the whirling at the projecting of the mirror 11 is made extremely small. With such constitution, the reproducibility of the mirror angles is made extremely high. |
