Laser Interferometer System for Straightness Measurements
A laser interferometer system can be used to measure the straightness of an object. A typical Hewlett-Packard's straightness interferometer system uses a Wollaston prism to split a laser beam traveling along a principal axis into two secondary beams. However, the resolution and the range of the respective interferometers are limited by the angular deviation of the secondary beams. In addition, the Wollaston prism has to be accurately paired with the straightness reflector, which makes them expensive. The straightness reflectors have to be accurately aligned with the Wollaston prism to ensure that the reflected beams re-combine in the prism.
A novel triangular prism laser interferometer system for measuring straightness of an object is invented. This interferometer employs special designed triangular prisms to refract the beams by certain angles with respect to the principal axis of the incident beam. There are two configurations of arrangement of the triangular prisms for the interferometer. One is for short range with high accuracy. Another is for long range with reasonable resolution. The invention utilizes a novel device to overcome the drawbacks of the current straightness interferometers in the areas of dynamics range and resolutions. The device has unlimited range and high resolution.
1. Unlimited range
2. High resolution
3. Lower cost
- Metrology
- Alignment techniques
- Precision engineering
- Manufacturing
Patent Number: US5757491A
Application Number: US1996699348A
Inventor: Cai, Lilong | Zhang, Jihua
Priority Date: 19 Aug 1996
Priority Number: US5757491A
Application Date: 19 Aug 1996
Publication Date: 26 May 1998
IPC Current: G01B001130
US Class: 356508 | 356358 | 356496 | 356361
Assignee Applicant: The Hong Kong University of Science & Technology
Title: Laser interferometer system for straightness measurements
Usefulness: Laser interferometer system for straightness measurements
Summary: USE For transverse vibration monitoring and server control systems.
Novelty: Laser interferometer for linearity measurement in metrology engineering fields has third and fourth triangular prisms that change optical path length of first and second beams and reflects first and second beams towards first and second triangular prisms,
光學
激光
19 Aug 1996
US 5757491
TTC.PA.034
香港
