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公开(公告)号:US20230301775A1
公开(公告)日:2023-09-28
申请号:US18023704
申请日:2021-10-07
Applicant: KOWA COMPANY, LTD.
Inventor: Shuji ABE , Yasuhiro HISHINUMA , Kotaro MITSUMOTO , Haruo ISHIKAWA , Norio SHIMIZU
IPC: A61F2/16
CPC classification number: A61F2/1618 , A61F2/1654 , G02B27/4205
Abstract: A multifocal diffractive lens is provided which achieves efficient use of light. The multifocal diffractive lens 100 includes a diffraction grating 1c. Negative-order light L2 produces a focal point f2 for far vision and 0-order light L1 produces a focal point f1 nearer to that for far vision. The number of focal points is two or more. The focal position fc for far vision in polychromatic performance evaluation is located nearer to the multifocal diffractive lens than the focal position fs for far vision in monochromatic performance evaluation.
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公开(公告)号:US20190167416A1
公开(公告)日:2019-06-06
申请号:US16309903
申请日:2017-06-14
Applicant: Kowa Company, Ltd.
Inventor: Haruo ISHIKAWA , Akemi TANIGUCHI , Norio SHIMIZU
IPC: A61F2/16
Abstract: There is provided a toric intraocular lens which improves the visibility of a toric axis. The toric intraocular lens is a toric intraocular lens including a lens body provided with an astigmatic axis. A mark indicating the astigmatic axis is formed at an optical surface of an outer rim portion of the lens body, and a length in a radial direction of the lens body and a length in a circumferential direction of the lens body of external dimensions of the mark are different from each other in top view of the optical surface.
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