Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
104 words
A method of correcting or alleviating presbyopia in a human comprising fitting contact lenses to the two eyes, at least one of the contact lenses having an optical zone adapted to provide a corrected near image and a corrected far image by reason of refractive power to provide one and diffractive power to provide the other, one of said corrected near and far images being of greater intensity than the other, and the other contact lens being adapted to provide a corrected high intensity image corresponding (in terms of near or far) to the corrected lower intensity image provided by said one contact lens.
Claim 2
Dependent Claim
209 words
A method of correcting or alleviating presbyopia in humans according to Claim 1 comprising (a) fitting a first contact lens to a first eye, said first contact lens having an optical zone adapted to provide a corrected near and far image for said first eye, and (b) fitting a second contact lens to the other eye, said second contact lens having an optical zone adapted to provide a corrected near and far image for said other eye, each lens having a first power provided by the shape, curvature and material of the lens to provide one corrected image and a second power provided by diffractive means to provide the other corrected image, said second power being additive to (or subtracted from) the first power, in which the diffractive means are arranged so that the amount of the light directed into the near image by one lens is substantially greater than that directed into the far image by that lens, and the amount of light directed into the far image by the other lens is substantially greater than that directed into the near image by that other lens, whereby each of the two eyes can see an image of relatively high intensity whilst retaining a large amount of stereoscopic vision.
Claim 3
Dependent Claim
40 words
A method in accordance with claim 1 or claim 2, wherein the contact lenses are fitted to a wearer so that refractive distance vision is provided by the dominant eye and refractive near vision is provided by the other eye.
Claim 4
Dependent Claim
83 words
A method in accordance with claim 2 or claim 3, wherein the distance eye is fitted with a lens having a refractive base power for distance images and a diffractive additive optical power of -2 dioptres with 25% of the light going into the diffractive image for near images, and the near eye having a refractive base power for near images and a diffractive additive optical power of +2 dioptres with 25% of the light going into the diffractive image for distance images.
Claim 5
Dependent Claim
74 words
A set of contact lenses for treating presbyopia in a human comprising a pair of lenses at least one of which provides one corrected image by refractive power and another corrected image by diffractive power, the two corrected images being near and far images of different intensities, the other lens providing a corrected high intensity image corresponding (in terms of near or far) to the corrected lower intensity image provided by said one lens.
Claim 6
Dependent Claim
117 words
A set of contact lenses for treating presbyopia in humans comprising a pair of lenses, each lens having a first power provided by the shape, curvature and material of the lens to provide one corrected image, and a second power provided by diffractive means to provide another corrected image, the lenses being paired so that one lens has diffractive means arranged so that the amount of light directed into the near image by the lens is substantially greater than that directed into the far image, and the other lens has diffractive means arranged so that the amount of light directed into the far image by the lens is substantially greater than that directed into the near image.