| 摘要 |
PURPOSE:To gauge the directivity of deviation of an optical axis due to the temperature change and prevent an unreversible deviation by providing an adhering means which sticks an optical assembly and a housing to each other and spanning this adhering means between both of them in one or several positions in a uniform spanning direction. CONSTITUTION:A position-adjusted optical assembly 14 is practically fixed with an adhesive 19 so that it is deviated approximately reversibly in accordance with the temperature change, and the adhesive 19 is so fixed that it is spanned between the optical assembly 14 and a housing 13 in the Y'-axis direction of an X'-Y' coordinate system in the figure where the center position to be adjusted between the optical assembly 14 and the housing 13 is the origin. In this adhering structure where the relative position relation between the optical assembly 14 and the housing 13 is determined by the spanning direction, it is clarified experimentally that the micro deviation of the optical assembly 14 appears remarkably in the Y'-axis direction in the figure and is restrained in the X'-axis direction; and that is, the deviation depends upon temperature characteristics in the same directions of the adhesive 19, and a deviated position (X', Y') of the X'-Y' coordinate system is restrained approximately to (0, Y'), and thus, the deviation is Y'- axis deviation. |
