Method of obtaining an optical FT spectrum

US5923422A · kind A · utility

Assignee

• Bruker Analytik GmbH · DE

Inventors

• Axel Keens · Karlsruhe, DE
• Norbert Rapp · Malsch, DE

Key dates

• Filing date: Feb 2, 1998
• Grant date: Jul 13, 1999
• Expiry date: Feb 2, 2018

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2021/3595
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method of obtaining an FT spectrum according to Brault is improved in that the compensation filter is determined by recording a broad-band effective interferogram, carrying out complex Fourier transformation, forming a mean value of the phase spectra, converting the abscissa values into electrical frequencies, and establishing the transfer function of the detector and of the further signal processing elements, wherein the free parameters of the transfer function are chosen such that the phase response of the transfer function deviates as little as possible from the mean value of the phase spectrum of the effective recorded interferogram. If necessary, the determined transfer function is then digitized. The compensation filter is then determined as the inverse of the discrete transfer function. In this way, deconvolution of the signal processing elements transfer function from the spectra is facilitated in a particularly simple and effective manner.