Microoptical sensor and method
US5455178A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 28, 1993 |
| Grant date | Oct 3, 1995 |
| Priority date | — |
| Expiry date | May 28, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S436/805
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A microoptical sensor and a corresponding method for detecting chemical substances in a sample. The sample is brought into contact with the waveguiding layer of a planar optical waveguide. Coherent light is coupled into the waveguiding layer, propagates therein as a guided wave, and the latter is decoupled from the waveguiding layer. Both, coupling and decoupling of the light wave guided in the planar waveguide is effected by means of a multi-diffractive grating situated in the plane of the layer, i.e. a grating structure comprising two or more fundamental frequency components for in-coupling and out-coupling, respectively. The multi-diffractive grating coupler results in a directional separation of decoupled light from reflected, transmitted and directly diffracted sub-beams, respectively. This makes possible a background-free detection of guided light decoupled from the waveguiding layer, although the regions on the waveguiding layer in which coupling and decoupling of the guided light wave take place overlap in part.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.