OPTICAL MEASURING APPARATUS

• US 20140340694A1
• Filed: 05/14/2014
• Published: 11/20/2014
• Est. Priority Date: 05/20/2013
• Status: Active Grant

• Current Assignee: Mitutoyo Corporation
• Original Assignee: Mitutoyo Corporation
• Inventors: FUKUDA, Shinji, IMAIZUMI, Ryoichi
• Granted Patent: US 9,423,241 B2
• Time in Patent Office: Days
• US Class Current: 356/635
• CPC Class Codes: G01B 11/08 for measuring diameters
• CPC Class Codes: G01B 11/2433 for measuring outlines by shadow casting

Abstract

An optical measuring apparatus includes a light emitter, a scanner, a polarizing plate, a photoreceiver, and a CPU. The light emitter emits a laser beam. The scanner uses the laser beam emitted from the light emitter and scans a measurement region where a work piece is placed. The polarizing plate allows passage for only a laser beam, among the laser beams fired by the scanner, directed orthogonally to an emission direction of the laser beam and an axis direction of the work piece. The photoreceiver receives the laser beam that has passed through the measurement region and the polarizing plate. The CPU calculates a dimension of the work piece from a pattern of light and dark in a scan direction, the pattern being obtained by the photoreceiver.

Claims

1. An optical measuring apparatus comprising:

a light emitter configured to emit a laser beam;

a scanner configured to convert the laser beam to a plurality of scanning laser beams, the scanner further configured to direct the plurality of scanning laser beams toward a measurement region where an object to be measured is placed;

a polarizing plate configured to allow passage of only a scanning laser beam of the plurality of scanning laser beams from the scanner orthogonally directed to an emission direction of the laser beam and an axis direction of the object to be measured;

a photoreceiver configured to receive the scanning laser beam that has passed through the measurement region and the polarizing plate; and

a dimension calculator configured to calculate a dimension of the measured object from a pattern of light and dark in a scanning direction, the pattern being obtained by the photoreceiver.

2. The optical measuring apparatus according to claim 1, wherein the polarizing plate is located between the scanner and the object to be measured.

3. The optical measuring apparatus according to claim 1, wherein the polarizing plate is located between the object to be measured and the photoreceiver.

4. The optical measuring apparatus according to claim 1, wherein the polarizing plate is detachable.

5. The optical measuring apparatus according to claim 2, wherein the polarizing plate is detachable.

6. The optical measuring apparatus according to claim 3, wherein the polarizing plate is detachable.