Patent ID: 9261404
Filing Date: 2016-02-16
CPC Classification: G01J,G01N

Claim Text:
1. An apparatus for measuring Raman radiation scattered from a target sample exposed to excitation radiation, characterised in that the apparatus comprises: a wall structure optically non-transparent to excitation radiation and having an optically transparent aperture therein, configured to have a sample located within or adjacent to said aperture during measurement of Raman radiation, the wall structure being located between a transmitter of excitation radiation and a receiver for Raman radiation; an optically reflecting surface, comprising a first hemispherical concave surface and second hemispherical concave surface; the first concave surface and the second concave surface being configured to face each other with an optical axis between them, and to have a distance of at least their combined hemispherical radii along the optical axes between them; the wall structure being between the concave surfaces and configured to optically isolate the concave surfaces from each other; the first concave surface comprising an input aperture for transmission of excitation radiation to the sample; the second concave surface comprising an output aperture for reception of the Raman radiation formed on the interaction between the sample and the excitation radiation on its way through the sample to the receiver, the second concave surface being configured to reflect the optical radiation passed through or reflected from the sample without hitting the output aperture back to the sample; and the reflecting surface being configured to reflect optical radiation scattered from the sample back to the sample for enhancing Raman radiation at the receiver.