Ophthalmic lens
AssigneeHoya Lens Thailand Ltd.
InventorsShohei Matsuoka, Yuki Iguchi, Hiroyuki Mukaiyama
Life of this patent
Estimating the term…
Abstract
Provided are an ophthalmic lens and a technique related thereto, the ophthalmic lens including two lens elements 1 and 2 having powers with different signs, in which when the Abbe number (e-line reference) of the lens element 1 having a power with a smaller absolute value is νe1, and the Abbe number (e-line reference) of the other lens element 2 is νe2, Formula 1 below is satisfied, and νe1<νe2 (Formula 1) when a partial dispersion ratio PgF′1 between the g-line and F′-line in the lens element 1 having the power with the smaller absolute value, and a partial dispersion ratio PgF′2 between the g-line and F′-line in the other lens element 2 are set, the following Formula 2 is satisfied. PgF′1>PgF′2 (Formula 2).
Claims5
An ophthalmic lens including two lens elements 1 and 2 having powers with different signs,
- wherein when an Abbe number (e-line reference) of the lens element 1 having a power with a smaller absolute value is νe1, and an Abbe number (e-line reference) of the other lens element 2 is νe2, Formula 1 below is satisfied,
- νe1<νe2 (Formula 1), and
- when a partial dispersion ratio PgF′1 between a g-line and an F′-line in the lens element 1 having the power with the smaller absolute value, and a partial dispersion ratio PgF′2 between a g-line and an F′-line in the other lens element 2 are set, Formula 2 below is satisfied,
- P′gF′1>P′gF′2 (Formula 2),
- wherein when the absolute value of the power of the lens element 1 is D1 and the absolute value of the power of the lens element 2 is D2, Formula 3 below is satisfied,
- (D1/νe1)<(D2/νe2) (Formula 3)
- wherein when the absolute value of the power of the lens element 1 is D1 and the absolute value of the power of the lens element 2 is D2, Formula 4 below is satisfied,
- {D1×(1+3×P′gF′1)/νe1}>{D2×(1+3×P′gF′2)/νe2} (Formula 4).
Dependencies are inferred from the claim text.