| 摘要 |
<p>An interference measuring device (1) comprises light sources (11 and 12), lenses (21 to 25), an aperture (31), an optical multiplexer (41), an optical branching filter (42), a half mirror (43), an imaging unit (51), an analyzing unit (52), a light receiving unit (61), a displacement detecting unit (62), a piezo-actuator (71), a drive unit (72), a mirror (73), a stage (81), a drive unit (82) and a control unit (90). On the basis of an optical path length difference detection result by the displacement detecting unit (62), the control unit (90) controls the optical path length difference adjusting operations by the piezoelectric actuator (71) and the stage (81) through the drive units (72 and 82) so that the optical path length difference may become a plurality of target values sequentially. In the moving operation by the stage (81), too, the control unit (90) subjects the moving operation by the piezoelectric actuator (71) to a feedback control so that the optical path length difference may become each of the target values.</p> |
