Fiber grating encoders and methods for fabricating the same
US6087655A · kind A · utility
Inventor
Key dates
| Filing date | May 19, 1998 |
| Grant date | Jul 11, 2000 |
| Priority date | — |
| Expiry date | May 19, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/02147
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Very long linear large diameter rotational, and arbitrary shape conformal fiber encoders are suggested. These devices are based on detection of non-zeroth diffraction order or interference pattern of selected diffraction orders from the fiber grating. Relative and absolute position detection or movement detection can be realized. Depending on the variety of disclosed configurations of fiber encoders, fiber grating could be either a fiber Bragg grating (refractive index modulation grating), a fiber surface-relief phase grating, or fiber amplitude or amplitude phase grating. Each of these fiber gratings may have a uniform or chirped period, and the fiber grating encoders may be implemented using transmission, reflection, or Bragg angle reflection schemes. An optical fiber may be manufactured on a continuous basis by drawing it from preform. Consequently, there is really no limitation to the length of the linear fiber based encoders. In addition, since fiber grating can be mounted on a circularly symmetric figure of arbitrary diameter, there is therefore no limitation on the manufacturable size of a rotary encoder. Due to flexibility of fibers, the proposed gratings can be mounted on …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.