Line-scan laser ophthalmoscope

• US 20030231285A1
• Filed: 06/14/2002
• Published: 12/18/2003
• Est. Priority Date: 06/14/2002
• Status: Active Grant

• Current Assignee: Physical Sciences Incorporated
• Original Assignee: Physical Sciences Incorporated
• Inventors: Ferguson, R. Daniel
• Granted Patent: US 6,758,564 B2
• Time in Patent Office: Days
• US Class Current: 351/221
• CPC Class Codes: A61B 3/1025 for confocal scanning

Abstract

Systems and methods for providing a line-scanning laser ophthalmoscope (LSLO) are disclosed. The LSLO uses a substantially point source of light, such as an infrared laser or a super-luminescent diode. The point source is expanded to a line. The LSLO scans the line of light in a direction perpendicular to the line across a region of an eye having an undilated pupil The reflected light is received confocally, using monostatic beam geometry. A beam separator, such as a turning prism or mirror, diverts one of the incoming light and the reflected light to separate the light. An optical stop prevents non-confocally received light from reaching a one-dimensional detector, such as a linear CCD array. An electrical signal responsive to the output light at each of a plurality of locations along the line of output light is processed to provide images of the scanned portion of the eye.

Claims

1. A line-scanning laser ophthalmoscope, comprising:

a light source providing a substantially point source of light;

an optical apparatus comprising;

an optical component that accepts the light from the laser and provides a line of incoming light;

at least one optical component that (i) scans a portion of an eye with the incoming line of light in a direction perpendicular to the line, (ii) confocally receives reflected light from the illuminated portion of the eye, and (iii) provides output light in a line focus configuration; and

a turning mirror that redirects a selected one of the incoming light and the reflected light; and

a one-dimensional detector that detects the output light and provides an electrical signal responsive to the output light at each of a plurality of locations along the line of output light.

2. The line-scanning laser ophthalmoscope of claim 1, wherein the light source providing a substantially point source of light comprises a laser.

3. The line-scanning laser ophthalmoscope of claim 1, wherein the light source providing a substantially point source of light comprises a super-luminescent diode.

4. The line-scanning laser ophthalmoscope of claim 1, wherein the optical component that accepts the light from the light source and provides a line of light comprises one or more lenses.

5. The line-scanning laser ophthalmoscope of claim 1, wherein the optical component that accepts the light from the light source and provides a line of light comprises a holographic optical element.

6. The line-scanning laser ophthalmoscope of claim 1, further comprising:

a signal analysis module that decodes the electrical signal from the one-dimensional detector and that generates an array of data representative of reflected light from the illuminated portion of the eye.

7. The line-scanning laser ophthalmoscope of claim 6, further comprising:

a display module that displays information representative of the array of data generated by the signal analysis module.

8. The line-scanning laser ophthalmoscope of claim 1, wherein the one-dimensional detector is a linear CCD array.

9. The line-scanning laser ophthalmoscope of claim 1, wherein the one-dimensional detector is a linear CMOS array.

10. The line-scanning laser ophthalmoscope of claim 1, wherein the laser is an infrared laser.

11. The line-scanning laser ophthalmoscope of claim 10, wherein the infrared laser operates at a wavelength in the range of 700 nm to 950 nm.

12. The line-scanning laser ophthalmoscope of claim 11, wherein the infrared laser operates at a wavelength of substantially 830 nm.

13. The line-scanning laser ophthalmoscope of claim 1, wherein the optical apparatus further comprises:

a scanning mirror that provides a scanned line of light having a scan direction perpendicular to the line of light;

one or more lenses that focus the scanned line of light on a portion of an eye;

one or more lenses that confocally receive reflected light from the illuminated portion of the eye and provide a line of reflected light;

a scanning mirror that redirects the line of reflected light;

a pupil stop that prevents unwanted light from proceeding through the optical apparatus; and

an objective lens that focuses the redirected line of reflected light onto the one-dimensional detector.

14. The line-scanning laser ophthalmoscope of claim 13, wherein the scanning mirror that intercepts the redirected line of light and provides a scanned line of light and the scanning mirror that redirects the line of reflected light are the same scanning mirror.

15. The line-scanning laser ophthalmoscope of claim 13, wherein the one or more lenses that focus the scanned line of light on a portion of an eye and the one or more lenses that confocally receive reflected light from the illuminated portion of the eye are the same one or more lenses.

16. The line-scanning laser ophthalmoscope of claim 13, wherein the pupil stop prevents non-confocally received light from proceeding through the optical apparatus.

17. A line-scanning ophthalmoscope, comprising:

a light source providing a substantially point source of light;

an optical apparatus (i) receiving light from the light source, (ii) scanning a portion of an eye with the line of light in a direction perpendicular to the line, (iii) confocally receiving reflected light from the illuminated portion of the eye, and (iv) providing output light in a line focus configuration; and

a one-dimensional detector detecting the output light and providing an electrical signal responsive to the output light at each of a plurality of locations along the line of output light.

18. A line-scanning laser ophthalmoscope, comprising:

a light source providing a substantially point source of light;

an optical apparatus comprising;

an optical component that accepts the light from the laser and provides a line of incoming light;

at least one optical component that (i) scans a portion of an eye having an undilated pupil with the incoming line of light in a direction perpendicular to the line, (ii) confocally receives reflected light from the illuminated portion of the eye, and (iii) provides output light in a line focus configuration; and

a turning mirror that redirects a selected one of the incoming light and the reflected light; and

a one-dimensional detector that detects the output light and provides an electrical signal responsive to the output light at each of a plurality of locations along the line of output light.

19. A line-scanning laser ophthalmoscope, comprising:

a light source providing a substantially point source of light;

an optical apparatus comprising;

an optical component that accepts the light from the laser and provides a line of incoming light;

at least one optical component that (i) scans a portion of an eye with the incoming line of light in a direction perpendicular to the line, (ii) confocally receives reflected light from the illuminated portion of the eye, the incoming line of light and the reflected light having monostatic beam geometry, and (iii) provides output light in a line focus configuration; and

a turning mirror that redirects a selected one of the incoming light and the reflected light; and

a one-dimensional detector that detects the output light and provides an electrical signal responsive to the output light at each of a plurality of locations along the line of output light.

20. A method of making a optical measurement of an object, comprising the steps of:

providing an incoming line of light;

scanning a portion of an object with the incoming line of light in a direction perpendicular to the line;

confocally receiving reflected light from the illuminated portion of the object;

providing output light in a line focus configuration from the received reflected light;

separating the incoming light and the output light;

detecting the output light; and

providing an electrical signal responsive to the output light at each of a plurality of locations along the line of output light.

21. The method of claim 20, wherein the object is an eye.

22. The method of claim 20, further comprising the steps of:

decoding the electrical signal; and

generating an array of data representative of reflected light from the illuminated portion of the object.

23. A method of making an ophthalmoscopic measurement, comprising the steps of:

providing an incoming line of light;

scanning a portion of an eye having an undilated pupil with the incoming line of light in a direction perpendicular to the line;

confocally receiving reflected light from the illuminated portion of the eye;

providing output light in a line focus configuration from the received reflected light;

separating the incoming light and the output light;

detecting the output light; and

providing an electrical signal responsive to the output light at each of a plurality of locations along the line of output light.

24. A method of making an ophthalmoscopic measurement, comprising the steps of:

providing an incoming line of light;

scanning a portion of an eye with the incoming line of light in a direction perpendicular to the line;

confocally receiving reflected light from the illuminated portion of the eye, using a monostatic beam geometry for the incoming line of light and the reflected light;

providing output light in a line focus configuration from the received reflected light;

separating the incoming light and the output light;

detecting the output light; and

providing an electrical signal responsive to the output light at each of a plurality of locations along the line of output light.