RELATIVE DISPLACEMENT MEASUREMENT DEVICE, POSITION MEASUREMENT DEVICE, AND ATTITUDE CONTROL DEVICE FOR MOVING BODY

摘要

PROBLEM TO BE SOLVED: To measure displacement (or position) of moving body set in the air with high precision. ;SOLUTION: A first moving body 12 is provided with two mirrors M₂ and M₃, while a second moving body 16 is provided with two mirrors M₄ and M₅. The mirror M₂ is tilted by θ while the mirror M₃ is tilted by π/2-θ. The mirrors M₄ and M₅ are allocated orthogonal to an optical axis. With these geometric conditions, by calculating a difference between output change amounts of light wave interferometers 10A and 10B before and after movement of the two moving bodies, relative displacement in moving direction is calculated. With the position of first moving body 12 identical with that of the second moving body 16, the position of second moving body 16 is measured at high precision as the position of the first moving body 12. A first space 14 is configured as a vacuum space while a second space 18 configured as an atmospheric space.;COPYRIGHT: (C)1999,JPO