OPTICAL MEASUREMENTS OF PROPERTIES IN SUBSTANCES USING PROPAGATION MODES OF LIGHT

• US 20110063616A1
• Filed: 11/16/2010
• Published: 03/17/2011
• Est. Priority Date: 06/04/2003
• Status: Abandoned Application

• Current Assignee: Tomophase Corporation
• Original Assignee: Tomophase Corporation
• Inventors: Wang, Feiling
• Application Number:
  US12/947,823
• Publication Number:
  US 20110063616A1
• Time in Patent Office: Days
• US Class Current: 356/369
• CPC Class Codes: A61B 2562/0242 for varying or adjusting the optical path length in the tissue
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/0066 Optical coherence imaging
• CPC Class Codes: A61B 5/0073 by tomography, i.e. reconstruction of 3D images from 2D projections A61B5/0066 takes precedence
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: A61B 5/14558 by polarisation
• CPC Class Codes: G01B 2290/35 Mechanical variable delay line
• CPC Class Codes: G01B 2290/40 Non-mechanical variable delay line
• CPC Class Codes: G01B 2290/45 Multiple detectors for detecting interferometer signals
• CPC Class Codes: G01B 2290/70 Using polarization in the interferometer
• CPC Class Codes: G01B 9/0201 using temporal phase variation
• CPC Class Codes: G01B 9/02044 Imaging in the frequency domain, e.g. by using a spectrometer
• CPC Class Codes: G01B 9/02057 by using common path configuration, i.e. reference and object path almost entirely overlapping
• CPC Class Codes: G01B 9/02091 Tomographic interferometers, e.g. based on optical coherence
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/021 using plane or convex mirrors, parallel phase plates, or particular reflectors
• CPC Class Codes: G01J 3/0218 using optical fibers
• CPC Class Codes: G01J 3/0224 using polarising or depolarising elements
• CPC Class Codes: G01J 3/42 Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry beam switching arrangements G01J3/08
• CPC Class Codes: G01N 2021/4709 : Backscatter
• CPC Class Codes: G01N 2021/4792 : Polarisation of scatter light
• CPC Class Codes: G01N 21/21 : Polarisation-affecting properties G01N21/19 takes precedence
• CPC Class Codes: G01N 21/27 : using photo-electric detection G01N21/31 takes precedence; circuits for computing concentration logarithmic circuits G06G7/24; photometric circuits in general G01J
• CPC Class Codes: G01N 21/474 : Details of optical heads therefor, e.g. using optical fibres
• CPC Class Codes: G01N 21/4795 : spatially resolved investigating of object in scattering medium in vivo A61B
• CPC Class Codes: G01N 21/49 : within a body or fluid
• CPC Class Codes: G01N 21/55 : Specular reflectivity
• CPC Class Codes: G02B 21/06 : Means for illuminating specimens

Abstract

This application describes designs, implementations, and techniques for controlling propagation mode or modes of light in a common optical path, which may include one or more waveguides, to sense a sample.

Claims

1. A device for optically measuring a sample, comprising:

a light source to produce an input beam for optically probing a sample;

a waveguide having a proximal end to receive the input beam from the light source and a distal end towards which the received input beam is guided by the waveguide;

a probe head coupled to the distal end of the waveguide to receive the input beam and to reflect a first portion of the input beam back to the waveguide and direct a second portion of the input beam to the sample, the probe head configured to overlap reflection of the second portion from the sample with the first portion and to export to the waveguide the reflection as a reflected second portion;

a differential delay modulator in optical communication with the proximate end of the waveguide to receive light in the first portion and the reflected second portion from the proximate end of the waveguide, the differential delay modulator operable to split the received light into a first beam and a second beam and to produce variable relative phase delays between the first beam and the second beam; and

a detection module to detect light that combines the first beam and the second beam and is output by the differential delay modulator, the detection module operable to extract information of the sample carried by the reflected second portion at different depths in the sample based the variable relative phase delays produced by the differential delay modulator.