Digitisation of interferograms in Fourier transform spectroscopy
US5914780A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 8, 1997 |
| Grant date | Jun 22, 1999 |
| Priority date | — |
| Expiry date | Oct 8, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J3/453
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Interferograms produced by a Michelson type interferometer used in Fourier Transform spectroscopy are processed by an arrangement which includes an analogue-to-digital converter (12) which is sampled by a fixed frequency clock signal to provide a digital representation of the interferogram. This signal is processed by a digital data processor (18) which also receives a digital representation of the reference fringe waveform to provide a digital output representing the interferogram. The digital representation of the reference fringe waveform may be produced by a second analogue-to-digital converter or by a timer. The analogue-to-digital converter may be arranged to produce oversampled representations of the interferogram or reference fringe waveforms. In one form of the invention the analogue-to-digital converter or converters include a delta sigma modulator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.