Simultaneous stereo fundus camera

• US 5,315,329 A
• Filed: 04/08/1992
• Issued: 05/24/1994
• Est. Priority Date: 03/08/1990
• Status: Expired due to Fees

• Current Assignee: Nishika Limited
• Original Assignee: Nishika Limited
• Inventors: McAdams, John B.
• Primary Examiner(s): Ben, Loha
• Assistant Examiner(s): PAPALAS, MICHAEL
• Application Number:
  US07/865,079
• Time in Patent Office: 776 Days
• Field of Search: 351/206, 351/211, 351/213, 351/221, 354/62, 356/243
• US Class Current: 351/206
• CPC Class Codes: A61B 3/0091 Fixation targets for viewing direction
• CPC Class Codes: A61B 3/12 for looking at the eye fundus, e.g. ophthalmoscopes A61B3/13 takes precedence
• CPC Class Codes: A61B 3/1225 using coherent radiation
• CPC Class Codes: A61B 3/14 Arrangements specially adapted for eye photography apparatus or arrangements for taking photographs per se G03B

Abstract

A stereo eye fundus camera capable of simultaneously recording a stereo pair of images of the fundus of an eye of a patient onto color photographic film for processing into a 3-D color photograph includes a light source for illuminating the patient'"'"'s eye fundus and stereo optics for projecting a stereo pair of images of the eye fundus onto the film. Provisions are made in the camera for recording an image of a standardized gray color scale on the film using light from the light source, for generating a reference target light beam of a predetermined size and shape and parfocal with the optical means and projecting it onto the eye fundus within the field of view while the eye fundus images are formed, whereby the reference target is recorded on the film with the eye fundus image, and for selectively generating right and left eye fixation light beams and projecting a selected one of them onto the corresponding eye of the patient at a predetermined position outside of the field of view of the photographic optics, whereby when the patient fixes on the projected fixation beam, the patient'"'"'s optical nerve is at a predetermined position in the field of view.

Claims

1. A stereo eye fundus camera capable of simultaneously recording a stereo pair of images of the fundus of an eye of a patient onto color photographic film comprising:

light source means for illuminating the patient'"'"'s eye fundus,

stereo optical means for projecting the stereo pair of images of the patient'"'"'s eye fundus while it is illuminated onto the film so that the images are recorded on the film, the optical means having a field of view that includes the optic nerve,

and means for projecting an image of a standardized gray color scale onto the film using light from the light source so that the gray color scale is recorded on the film.

2. A stereo eye fundus camera according to claim 1 wherein the means for projecting the gray scale image is adapted to project it simultaneously with the recording of the fundus images.

3. A stereo eye fundus camera according to claim 1 and further comprising:

means for generating a reference target light beam of a predetermined size and shape and parfocal with the optical means and projecting it onto the eye fundus within the field of the view while the eye fundus images are formed, whereby the reference target is recorded on the film with the eye fundus image.

4. A stereo eye fundus camera according to claim 3 wherein the reference target generating means is adapted to project the reference target light beam onto the eye fundus at a location spaced apart from the optic nerve.

5. A stereo eye fundus camera according to claim 4 wherein the reference target generating means is adapted to project the reference target light beam onto the eye fundus only when the eye fundus images are being recorded.

6. A stereo eye fundus camera according to claim 1 and further comprising:

means for selectively generating right and left eye fixation light beams and projecting a selected one of them onto the corresponding eye of the patient at a predetermined position outside of the field of view of the optical means, whereby when the patient fixes on the projected fixation beam, the patient'"'"'s optical nerve is at a predetermined position in the field of view.

7. A stereo eye fundus camera capable of simultaneously recording a stereo pair of images of the fundus of an eye of a patient onto color photographic film comprising:

light source means for illuminating the patient'"'"'s eye fundus,

stereo optical means for projecting a stereo pair of images of the patient'"'"'s fundus while it is illuminated onto the film so that the stereo pair of images are recorded on the film, the optical means having a field of view that includes the optic nerve,

means for projecting an image of a standardized gray color scale onto the film using light from the light source so that the gray color scale is recorded on the film, and

means for generating a reference target and scaler light beam of a predetermined size and shape and including elements extending vertically and horizontally, the light beam being parfocal with the optical means, and for projecting the light beam onto the eye fundus within the field of view of the camera but outside of the optic nerve head of the eye fundus while the eye fundus images are formed, whereby an image of the reference target and scaler light beam is recorded as an indicia on the film with the eye fundus image.

8. A stereo eye fundus camera according to claim 7 wherein the reference target and scaler generating means is adapted to project the reference target and scaler light beam onto the eye fundus only when the eye fundus images are being recorded.

9. A stereo eye fundus camera according to claim 7 wherein the reference target and scaler light beam is in the form of a cross having a predetermined length in each direction.