Geodesic Lenses for Integrated Optic Circuits.
Abstract
Under this program, we have successfully developed the ultrasonic impact grinding technique for the fabrication of aspherical geodesic lens depressions. The lens radius is 4 mm and the depth is 1.374 mm. 15% of the lens aperture is allocated for a curved rounding at the edge of the depression. The designed focal length is 10.2 mm for an aberration free aperture of 6.8 mm. The technique of ultrasonic impact grinding is proved to be precise, fast and economic. Reproducible results can be easily obtained. The tool wear problem can be neglected if more than two tools are used for grinding the lens. We have demonstrated that depth variation within 7.5 micrometers for 5 depressions can be obtained using two tools. One of the 5 depressions has the exact designed depth. The consistency of the lens depressions can be further improved if a third tool is used. The grinding process is fast using the 200 W Bullen machine. It takes onlt 45 sec. to grind a 1.4 mm deep, 8 mm diameter depression in LiNbO3 substrate.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1979
- Accession Number
- ADA069711
Entities
People
- Bingjie Chen
- O. G. Ramer
Organizations
- HRL Laboratories