Verfahren und Vorrichtung zur exakten Rekonstruktion der Objektwelle in digitaler off-axis Holographie

Details

Veröffentlichungs-Nr.

EP2565725

Aktenzeichen

EP11179946

Anmeldetag

2. September 2011

Veröffentlichung

30. April 2014

Erteilung

30. April 2014

Rechtsraum

EP

IPC

G03H1/08// G03H1/28

Abstract

The invention provides a method and an apparatus for preparing a digital hologram representing an object (9), comprising generating a measurement beam (11) and two reference beams (10,12), irradiating the object (9) by the measurement beam and guiding the reflected measurement beam to an optical sensor (7), guiding the reference beams to mirror means (5) extending under a slanting angle and guiding the reflected beams to the sensor (7) to make the beams generate an interference pattern on the sensor, providing a digital signal representing the pattern on the sensor, processing the signal to obtain a digital hologram, subjecting the digital hologram to a Fourier transform in the spatial frequency domain to obtain a spectrum comprising a DC-term, two image terms (R<1>*O,R<2>*O), and two conjugate image terms (R<1>O*,R<2>O*), filtering the spectrum to obtain a term representing the object and replacing a section of an image term overlapped by the DC-term by the corresponding section of the other image term.

Anmelder

Firma

Mitutoyo Corporation

Land

🇯🇵 Japan

Fachgebiete