Hyperspectral retinal imager

• US 6,992,775 B2
• Filed: 08/29/2003
• Issued: 01/31/2006
• Est. Priority Date: 08/29/2002
• Status: Active Grant

• Current Assignee: Kestrel Corp.
• Original Assignee: Kestrel Corp.
• Inventors: Soliz, Peter, Otten, Leonard John III, Truitt, Paul Wiley
• Primary Examiner(s): Turner, Samuel A.
• Application Number:
  US10/651,491
• Publication Number:
  US 20040085542A1
• Time in Patent Office: 886 Days
• Field of Search: 356/451, 356/456, 250/339.08, 250/339.09
• US Class Current: 356/456
• CPC Class Codes: A61B 3/12 for looking at the eye fundus, e.g. ophthalmoscopes A61B3/13 takes precedence
• CPC Class Codes: G01J 3/28 Investigating the spectrum using colour filters G01J3/51
• CPC Class Codes: G01J 3/2823 Imaging spectrometer
• CPC Class Codes: G01J 3/453 by correlation of the amplitudes

Abstract

An ophthalmic instrument (for obtaining high resolution, wide field of area hyperspectral retinal images for various sized eyes) includes a fundus retinal imager, (which includes optics for illuminating and imaging the retina of the eye); apparatus for generating a real time image of the area being imaged and the location of the hyperspectral region of interest; a high efficiency spatially modulated common path Fourier transform hyperspectral imager, a high resolution detector optically coupled to the hyperspectral and fundus imager optics; and a computer (which is connected to the real time scene imager, the illumination source, and the high resolution camera) including an algorithm for recovery and calibration of the hyperspectral images.

Claims

1. An apparatus for measuring a spectral intensity of a retina as a function of wavelength for a spatial region of the retina, the apparatus comprising:

an optical device for viewing the spatial region of the retina, the optical device being optically connected to a high efficiency spatially modulated Fourier imaging Interferometer;

an illumination source for illuminating the spatial region; and

at least one detector for detecting a spectral signature of a spatial region imaged.

2. The apparatus for measuring a spectral intensity of a retina as a function of wavelength for a spatial region of the retina as described in claim 1, wherein the spatial region of the retina is illuminated by a single exposure of light.

3. The apparatus for measuring a spectral intensity of a retina as a function of wavelength for the spatial region of the retina as described in claim 1, further comprising a calibration source.

4. The apparatus of claim 1 wherein the optical device is a fundus imager.

5. An apparatus for measuring a spectral intensity of a scene as a function of wavelength for a spatial region of the scene, the apparatus comprising:

a high efficiency spatially modulated Fourier imaging interferometer;

a fundus manager for observing a spatial region to be illuminated;

means for illuminating the spatial region with a single exposure of light;

means for collecting light from the spatial region illuminated;

optics adapted to pass collected light from the spatial region illuminated through the interferometer to one or more detectors thereby creating an image;

means far measuring an intensity from an illumination source with a calibration source; and

an output monitor for displaying a calibrated spectral signature of the spatial region.

6. A method for measuring a spectral intensity of a retina as a function of wavelength for a spatial region of the retina, the method comprising:

observing the spatial region with an optical device;

illuminating the spatial region with a single exposure of light;

collecting the light from the spatial region illuminated;

passing collected light through a high efficiency spatially modulated Fourier interferometer to one or more detectors;

calibrating an image collected with a signal measured from a calibration source; and

viewing a calibrated spectral signature of the spatial region.

7. A method for assessing metabolic function change of a retina based on hyperspectral images of the retina, the method comprising:

illuminating a spatial region of a retina with a single exposure of light at a first time;

collecting the light from the spatial region illuminated at the first time;

passing light collected at the fast time through a high efficiency spatially modulated Fourier interferometer to one or more detectors;

calibrating a first hyperspectral image of the retina from the light passed through the high efficiency spatially modulated Fourier interferometer at the first time with a signal measured from a calibration source at the first time;

recording the first hyperspectral image;

illuminating the spatial region of the retina with a single exposure of light at a second time;

collecting, the light from the spatial region illuminated at the second time;

passing light collected at the second time through the high efficiency spatially modulated Fourier interferometer to the one or more detectors;

calibrating a second hyperspectral image of the retina from the light passed through the high efficiency spatially modulated Fourier interferometer at the second time with a signal measured by the calibration source at the second time;

recording the second hyperspectral image; and

assessing metabolic function change of the retina based upon differences in spectral intensity between the first image and the second image.

8. The method for assessing metabolic function change of a retina as recited in claim 7, wherein assessing comprises applying principal components analysis to the reflectance differences.

9. The method for assessing metabolic function change of a retina as recited in claim 7, wherein assessing comprises applying a fast-Independent Component Analysis algorithm to the first and second images.

10. The method for assessing metabolic function change of a retina as recited in claim 7, wherein assessing comprises applying an extended spatial decorrelation algorithm to the images.