THICKNESS MEASURING DEVICE

• Main Authors: WATANABE MOTOYUKI, MIYAGI MASASHI, MIYAZAKI TAKAHIRO
• Format: Patent
• Language: English
• Published: 15.10.2009
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; MEASURING; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS; MEASURING LENGTH, THICKNESS OR SIMILAR LINEARDIMENSIONS; PHYSICS; SEMICONDUCTOR DEVICES; TESTING

PROBLEM TO BE SOLVED: To provide a thickness measuring device capable of measuring the thickness of a measuring object of a wider range regarding a material or a surface condition. SOLUTION: A measuring light outputted from a measuring light source 11 becomes a reference light by being reflected on a mirror 14c, becomes a first reflected light by being reflected on a first face 2a of the measuring object 2, becomes a second reflected light by being reflected on a second face 2b of the measuring object 2, and becomes a third reflected light by being reflected on a mirror M5. The light path length of the reference light is variable. The reference light, the first reflected light, the second reflected light, and the third reflected light are received by a light detector 15. The thickness of the measuring object 2 is calculated by a thickness calculation part 16 based on the light path length of the reference light path when an interference light generated by interference of the reference light and the first reflected light is received by the light detector 15 and the detected light strength is at its peak, and the light path length of the reference light path when the interference light generated by interference between the reference light and the second reflected light is received by the light detector 15 and the detected light strength is at its peak. COPYRIGHT: (C)2010,JPO&INPIT