Diagnostic ophthalmic lens using extra-low dispersion (ED) material

Abstract

An improved diagnostic ophthalmic lens using extra-low dispersion material, defined by having an Abbe Number, Vd>80, is provided. Such a single element diagnostic ophthalmic lens may be used for examination of the eye in conjunction with either an Indirect Ophthalmoscope or a Slit Lamp Biomicroscope.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the retinal image formation by a diagnostic ophthalmic lens of the presently described embodiments.

FIG. 2 illustrates the use of a diagnostic ophthalmic lens of the presently described embodiments with either an indirect ophthalmoscope or a slit lamp biomicroscope.

FIG. 3 shows a graphical representation of material dispersion via a plot of wavelength versus index of refraction.

FIG. 4 shows a cross-sectional view of an exemplary lens mounted in a housing as one example of an embodiment of those presently described.

FIG. 5 is a perspective view of the lens of FIG. 4.

Claims

1. A diagnostic ophthalmic lens assembly comprising: a lens element formed from a material having an Abbe Number greater than 80 (Vd>80); and,a housing in which said lens element is positioned.

2. The diagnostic ophthalmic lens assembly of claim 1, wherein surfaces of the lens element are aspheric.

3. The diagnostic ophthalmic lens assembly of claim 1, wherein surfaces of the lens element are spherical.

4. The diagnostic ophthalmic lens assembly of claim 1, wherein one surface of the lens element is aspheric and another surface of the lens element is spherical.

5. The diagnostic ophthalmic lens assembly of claim 1, wherein said lens assembly is used in conjunction with an Indirect Ophthalmoscope.

6. The diagnostic ophthalmic lens assembly of claim 1, wherein the optical power of said lens element is about 10 to about 55 diopters.

7. The diagnostic ophthalmic lens assembly of claim 1, wherein said lens assembly is used in conjunction with a Slit Lamp Biomicroscope.

8. The diagnostic ophthalmic lens assembly of claim 1, wherein the optical power of said lens element is about 60 to about 130 diopters.

9. The diagnostic ophthalmic lens assembly of claim 1 wherein the material is a fluor-crown glass.

10. The diagnostic ophthalmic lens assembly of claim 1 wherein the material is extra-low dispersion glass.

11. The diagnostic ophthalmic lens assembly of claim 1 wherein the material is a fluorite.

12. The diagnostic ophthalmic lens assembly of claim 1 wherein the material is a polymer.

13. The diagnostic ophthalmic lens assembly of claim 1 wherein the lens element is a single lens element.

14. A method for forming a diagnostic ophthalmic lens assembly comprising: forming a lens element for diagnostic ophthalmic use from an extra-low dispersion material; and,positioning the lens element within a housing.

15. The method of claim 14 further comprising using the lens assembly in conjunction with an Indirect Ophthalmoscope.

16. The method of claim 14 further comprising using the lens assembly in conjunction with a Slit Lamp Biomicroscope.

17. The method of claim 14 wherein the extra-low dispersion material has an Abbe number greater than 80.

18. A diagnostic ophthalmic lens system comprising: a lens element formed from an Extra-low dispersion material; and,a housing in which the lens element is positioned.

19. The system of claim 18 further comprising an Indirect Ophthalmoscope.

20. The system of claim 18 further comprising a Slit Lamp Biomicroscope.