| 摘要 |
PURPOSE:To enable optical paths to almost coincide even using an ordinary slide base with the correction of mal-alignment in the optical paths by providing a detector for detecting mal-alignment in the optical paths to turn a mobile flat mirror longitudinally or horizontally depending on the detection output. CONSTITUTION:A mal-alignment detector 51 comprising a 4-split photoelectric element 63 is provided to detect mal-alignment of a mobile flat mirror 5 and electrostrictive elements 71 and 74 to turn the flat mirror 5 longitudinally or horizontally. Mal-alignment signal 52 of the detector 51 is separated into two i.e. vertical oscillation signal and the eccentrical oscillation signal. The former drives a vertical oscillation displacing mechanism 57 through a displacement driving circuit 55 while the latter does an eccentrical oscillation displacing mechanism 58 through a displacement driving circuit 56 to drive the electrostrictive elements 71-74 so that the mirror 5 is turned longitudinally or horizontally to decrease the mal-alignment of the flat mirror 5. This enables the correction of difference between the optical paths to almost coincide with both of the optical paths even using an ordinary slide base. |
