Eye refractive power measuring apparatus having opacity discriminant function of crystalline lens
AssigneeNidek Co., Ltd.
InventorToshiaki Mizuno
Life of this patent
Estimating the term…
Abstract
An eye refractive power measuring apparatus having an opacity discriminant function of a crystalline lens comprising a projecting optical system for projecting a target for eye refractive power measurement onto a fundus of an eye to be examined, a detecting optical system for detecting the target image reflected from the eye fundus, a device coupled to the detecting optical system for measuring refractive power of the eye in response to the detected target image, an irradiating optical system for irradiating the eye fundus with a retroillumination light, and an observing optical system for observing a crystalline lens of the eye illuminated by the retroillumination light reflected from the eye fundus to determine the opacity of the crystalline lens.
Claims16
An eye refractive power measuring apparatus having a crystalline lens opacity discriminant function comprising:
- a projecting optical system for projecting a target onto a fundus of an eye under examination to measure the refractive power thereof;
- a detecting optical system for detecting an image of the target reflected from the eye fundus;
- means coupled to said detecting optical system for measuring the refractive power of the eye in response to said detected target image;
- an alignment observing optical system for observing the eye when measuring the refractive power thereof;
- an irradiating optical system for irradiating the eye fundus with a retroillumination light;
- and
- an observing optical system, for observing a crystalline lens of the eye illuminated by the retroillumination light reflected form the eye fundus to determine the opacity of the crystalline lens, including at least one magnification variable lens disposed on an optical path of said reflected retroillumination light;
- wherein said alignment observing optical system and said observing optical system for observing crystalline lens are included in an optical system, and the optical system displays selectively the image of the target reflected from the eye fundus for alignment observation and the image of the crystalline lens by selecting a magnification of the variable lens.
Dependencies are inferred from the claim text.