US 2010/0141956 A1 · DUAL BEAM HETERODYNE FOURIER DOMAIN OPTICAL COHERENCE TOMOGRAPHY

Abstract

The present invention relates to an apparatus and a method combining achromatic complex FDOCT signal reconstruction with a common path and dual beam configuration. The complex signal reconstruction allows resolving the complex ambiguity of the Fourier transform and to enhance the achievable depth range by a factor of two. The dual beam configuration shares the property of high phase stability with common path FDOCT. This is of importance for a proper complex signal reconstruction and is in particular useful in combination with handheld probes such as in endoscopy and catheter applications. The advantages of the present invention are in particular the flexibility to choose arbitrarily positioned interfaces in the sample arm as reference together with the possibility to compensate for dispersion.

Claims9

Dependent claims

An optical apparatus comprising:

a) a broad spectral bandwidth light source, a sample area and an illuminated region adapted to illuminate a sample, b) optical means to split the source field and to produce a reference light field and a sample light field, c) optical means to combine said light fields, d) optical and electronic means to record the spectral interference pattern between said light fields, e) means to introduce a controlled dynamic phase shift between the sample and the reference light field during signal integration, f) means to synchronize the above phase shift with the detection, where the dynamic phase change is adapted to be-tuned to detect, independent of the detection rate and with high sensitivity, the signal of a sample, or of any sample interface moving at arbitrary velocity.

Dependencies are inferred from the claim text.

Facts

Application

12/523,398Filed 21 Jan 2008

Priority

IB PCT/IB2007/05019320 Jan 2007

Published

10 Jun 2010

Term ends

Not estimatedThe source records don’t support an estimate.

Classification10 codes

G01N 21/4795
Scattering, i.e. diffuse reflection: spatially resolved investigating of object in scattering medium
G01B 9/02003
Using two or more frequencies: using beat frequencies
G01B 9/02044
Characterised by particular imaging or detection techniques: imaging in the frequency domain, e.g. by using a spectrometer
G01B 9/02057
Passive reduction of errors: by using common path configuration, i.e. reference and object path almost entirely overlapping

Dual beam heterodyne fourier domain optical coherence tomography

Life of this patent

Dual beam heterodyne fourier domain optical coherence tomography

Life of this patent

Abstract

Claims9