Patent Number: 6,166,818

Title: Interference measurement apparatus, interference measurement probe and interference measurement control system

Abstract: An optical system is fabricated in the form of one device, so that the simplified optical system is realized. A displacement is measured with a high resolving power utilizing an interference fringe. An interference measurement probe 2 receives a coherent light from a light source section 1, and divides the coherent light into a plurality of luminous fluxes. The interference measurement probe 2 emits a plurality of irradiation luminous fluxes at different angles. The plurality of irradiation luminous fluxes form an interference fringe and the interference fringe is irradiated onto an objective 8. A light receiving section 3 is disposed at a position where a reflection luminous flux from the objective 8 interferes, and receives an interference light reflected from the objective 8, thereby outputting a light receiving signal which is converted to an electric signal. A measurement section 4 performs processing for obtaining displacement of positions of the interference measurement probe 2 and the light receiving section 3 as well as displacement of the objective 8. A control section 5 is connected to a driving section 6, and controls the driving section 6 based on a measurement result of the measurement section 4, thereby making a stage 7 move in the Z-direction. On the stage 7, the objective 8 is mounted or provided.

Inventors: Nagano; Shigenori (Tokyo, JP), Hori; Nobuo (Tokyo, JP), Fujino; Makoto (Tokyo, JP)

Assignee: Kabushiki Kaisha Topcon

International Classification: G01B 9/02 (20060101); G01D 5/26 (20060101); G01B 009/02 ()

Expiration Date: 12/26/2017