Process for producing HOE's for use in combination to produce a telecentric beam
US4955694A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 27, 1988 |
| Grant date | Sep 11, 1990 |
| Priority date | — |
| Expiry date | Oct 27, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S359/90
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A light beam is repeatedly deflected in the longitudinal direction through a holographic element HOE by means of a rotating multi-faceted mirror. This HOE is so formed that the beam entering at different angles leaves the HOE as a telecentric beam. Through a further HOE the telecentric beam is diffracted onto an opto-electric transducer. In the region of the telecentric beam is located an object to be measured, and the time of the interruption of the telecentric beam by means of this object enables the dimension of the latter to be determined. The production of the telecentric beam and the deflection of the latter onto the transducer by means of the HOE allows a simple cost-effect manufacture as well as a simple evaluation of the measurements with increased precision. The manufacture of the HOE is likewise simple.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.