A measurement method based on the Radon transformation of plane orthogonal-grating image is proposed for measuring the micro-displacement and rotation of a precision worktable. A test table is constructed
which is mainly composed of micro-photography device and plane orthogonal-grating. The grating spaces and angles of the plane orthogonal-grating images are identified under different conditions
and the displacement experiment of the precision worktable is conducted. The experiment results show that Radon transformation is insensitive to measuring noise and the grating position and angles of plane orthogonal-grating image can be easily identified; the displacement of the worktable can be measured accurately
and the measuring error gets within 1 μm. By a analyzing the resolution capacity of the current measuring system
the measuring system configuration for further enhancing precision is proposed
where the camera lens and adapter in micro-photography device become unnecessary
and the amplified grating image is directly received by CCD sensor.
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