Shape measurement device and shape measurement method

A shape measurement method of a shape measurement device,

• wherein the shape measurement device comprises:
• a laser range finder part being fixed to a flat table and being capable of measuring a distance from a starting point of a laser beam to an irradiation point irradiated by the laser beam;
• a cylindrical rotation part being installed at an end part of the flat table, and making a rotational axis of a rotatable cylinder part coincide with the laser beam from the laser range finder part;
• a holding part having a first surface and a second surface, the first surface having a passage hole through which the laser beam passes and fixed to an end part of the cylinder part of a cylindrical rotation part irradiating the laser beam, and the second surface having a cylindrical hole and being provided in a direction perpendicular to the first surface;
• a mirror rotation part being fixed to the second surface, and rotatably attaching an end part of a columnar part to the cylindrical hole in a state where a rotation axis of the columnar part coincides with the laser beam from the laser range finder part;
• and
• a mirror being fixed to an end part of the columnar part, disposing a reflection surface on an extension line of the rotation axis of the columnar part, and reflecting the laser beam from the laser range finder part,
• wherein the shape measurement method comprises:
• a first point measurement control step for rotating the cylinder part to a predetermined reference cylindrical angle, rotating the columnar part to a predetermined reference mirror angle, making the laser beam irradiate, and measuring a position of a predetermined first point in a hollow from a reflection point of the laser beam on the mirror;
• a first rotation control step for rotating the cylinder part from the reference cylindrical angle to 180 degrees;
• a second rotation control step for rotating the columnar part from the reference mirror angle to an inversion angle that is line-symmetric with respect to the laser beam irradiated from an end part of the cylinder part;
• a second point measurement control step for making the laser beam irradiate after the cylinder part is rotated by 180 degrees, and the columnar part is rotated by the inversion angle, and measuring a position of a predetermined second point in the hollow from the reflection point of the laser beam on the mirror;
• and
• a correction control step for correcting a rotation operation of the cylinder part from the reference cylindrical angle to 180 degrees, and correcting a rotation operation of the columnar part from the reference mirror angle to the inversion angle so that the position of the second point coincides with the position of the first point.