Title:
眼鏡用レンズ
Document Type and Number:
Japanese Patent JP7142956
Kind Code:
B2
Abstract:
To provide a lens for spectacles capable of obtaining better depth of field extension effect than before in a region close to a lens peripheral edge, and having a lens front surface with a curvature radius of 150 mm or less.SOLUTION: In a lens for spectacles, a front surface of the lens is set to have a curvature radius of 150 mm or less. In a depth of field extension area set on the entire surface or part of the lens, the average power measured with the wearer's frontal line of sight and the optical axis of the lens aligned, or the average power measured with the optical axis of the lens tilted at a predetermined warpage angle with respect to the wearer's front line of sight changes from the optical center of the lens toward the periphery of the lens on the minus side, and at the same time, the amount of change in power in a first region where a rotation angle of the eyeball is within the range of 0 to 20 degrees and the amount of change in power in a second region where the rotation angle of the eyeball is within the range of 20 to 40 degrees are both within the range of 0.14 to 0.46 diopter.SELECTED DRAWING: Figure 5
Inventors:
Yasushi Miyajima
Application Number:
JP2020188046A
Publication Date:
September 28, 2022
Filing Date:
November 11, 2020
Export Citation:
Assignee:
Ito Optical Co., Ltd.
International Classes:
G02C7/02
Domestic Patent References:
| JP2017058632A | ||||
| JP2016206338A | ||||
| JP2006030316A | ||||
| JP2006337516A | ||||
| JP2005284059A | ||||
| JP2014522672A | ||||
| JP58024112A |
Attorney, Agent or Firm:
Akio Iida
Michiko Ema
Chiori Ueda
Toshiyuki Ando
Isao Namagawa
Michiko Ema
Chiori Ueda
Toshiyuki Ando
Isao Namagawa