Lens for a FT-raman microscope

US5493443A · kind A · utility

Assignee

• Bruker Analytische Messtechnik GmbH · DE

Inventors

• Arno Simon · Ettlingen, DE
• Reiner Schubel · Karlsruhe, DE

Key dates

• Filing date: Dec 10, 1993
• Grant date: Feb 20, 1996
• Expiry date: Dec 10, 2013

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B21/00
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

In a Raman microscope, in particular for a Fourier transform (FT) spectrometer with a lens for magnified imaging of a point-shaped region (1) on a surface of a measuring sample (2) and with a laser for irradiating laser radiation onto the point-shaped region (1), the laser radiation is in the infrared (IR), preferentially in the near-infrared (NIR) region and the lens is a Cassegrain mirror-lens (3, 4) with a convex mirror (3) arranged rotationally symmetrically to an optical axis (5) and with a concave mirror (4) which is likewise rotationally symmetric to the optical axis (5) of the lens, whereby the focal point of the concave mirror (4), lying on the optical axis (5), coincides with the point-shaped region (1) on the surface of the measuring sample (2). In this fashion distortion-free NIR Raman spectra can be taken with simple optical elements.