Richard E Farrell

US Patent:

6511420, Jan 28, 2003

Filed:

Aug 6, 1999

Appl. No.:

09/370646

Inventors:

Richard A. Farrell - Laurel MD
Russell L. McCally - Columbia MD

Assignee:

The Johns Hopkins University - Baltimore MD

International Classification:

A61B 104

US Classification:

600167, 600162, 600200, 351205

Abstract:

A hand-held ophthalmoscope modified by the removal or augmentation of the focusing wheel and the addition of a manual or automatic focusing lens system. An electronic imager (CCD array or video camera) is placed optically conjugate to a viewing screen such that focus operations performed by the examiner to adjust the image seen by the examiner on the screen also focuses the image on the electronic imager. This is accomplished by an optical system which includes a straight path from the viewing screen to the patients eye with a beam splitter interposed to cause the image of the patients eye to be reflected onto the imager. As a result, when the examiner uses the focusing lens system, manual or automatic, positioned between the beam splitter and the patients eye, to affect the image viewed by the examiner, the focus of the imager is simultaneously affected as well. Alternatively, the image from the imager is sent to a liquid crystal display (LCD) in the instruments eye piece; when the examiner focuses the image on the LCD, the image on the imager is focused simultaneously. Also provided is an automatic focusing system for the imager that operates independently of the examiners focusing adjustments.

US Patent:

20030114733, Jun 19, 2003

Filed:

Jan 27, 2003

Appl. No.:

10/351879

Inventors:

Richard Farrell - Laurel MD, US
Lorenz Happel - Ellicott City MD, US
Russell McCally - Columbia MD, US
Donald Duncan - Silver Spring MD, US
Kevin Baldwin - Baltimore MD, US

International Classification:

A61B001/267

US Classification:

600/167000, 600/200000

Abstract:

A hand-held ophthalmoscope modified by the removal or augmentation of the focusing wheel and the addition of a manual or automatic focusing lens system. An electronic imager (CCD array or video camera) is placed optically conjugate to a viewing screen such that focus operations performed by the examiner to adjust the image seen by the examiner on the screen also focuses the image on the electronic imager. This is accomplished by an optical system which includes a straight path from the viewing screen to the patient's eye with a beam splitter interposed to cause the image of the patient's eye to be reflected onto the imager. As a result, when the examiner uses the focusing lens system, manual or automatic, positioned between the beam splitter and the patient's eye, to affect the image viewed by the examiner, the focus of the imager is simultaneously affected as well. Alternatively, the image from the imager is sent to a liquid crystal display (LCD) in the instrument's eye piece; when the examiner focuses the image on the LCD, the image on the imager is focused simultaneously. Also provided is an automatic focusing system for the imager that operates independently of the examiner's focusing adjustments. An automatic focusing system for the imager can also be incorporated in the other two embodiments. The output from the electronic imager can be in digital or analog form and can consist of a single frame or a video stream.

US Patent:

20050234300, Oct 20, 2005

Filed:

Jun 15, 2005

Appl. No.:

11/153203

Inventors:

Richard Farrell - Laurel MD, US
Lorenz Happel - Ellicott City MD, US
Russell McCally - Columbia MD, US
Donald Duncan - Silver Spring MD, US
Kevin Baldwin - Baltimore MD, US

International Classification:

A61B001/04

US Classification:

600167000, 600109000

Abstract:

A hand-held ophthalmoscope modified by the removal or augmentation of the focusing wheel and the addition of a manual or automatic focusing lens system. An electronic imager (CCD array or video camera) is placed optically conjugate to a viewing screen such that focus operations performed by the examiner to adjust the image seen by the examiner on the screen also focuses the image on the electronic imager. This is accomplished by an optical system which includes a straight path from the viewing screen to the patient's eye with a beam splitter interposed to cause the image of the patient's eye to be reflected onto the imager. As a result, when the examiner uses the focusing lens system, manual or automatic, positioned between the beam splitter and the patient's eye, to affect the image viewed by the examiner, the focus of the imager is simultaneously affected as well. Alternatively, the image from the imager is sent to a liquid crystal display (LCD) in the instrument's eye piece; when the examiner focuses the image on the LCD, the image on the imager is focused simultaneously. Also provided is an automatic focusing system for the imager that operates independently of the examiner's focusing adjustments. An automatic focusing system for the imager can also be incorporated in the other two embodiments. The output from the electronic imager can be in digital or analog form and can consist of a single frame or a video stream.