Optical Lens, Method for Designing Optical Lens, and Apparatus for Manufacturing Optical Lens

• US 20130083288A1
• Filed: 09/13/2012
• Published: 04/04/2013
• Est. Priority Date: 09/30/2011
• Status: Active Grant

• Current Assignee: EHS Lens Philippines, Inc.
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: SHINOHARA, Toshihide, KAGA, Tadashi, MORI, Takateru
• Granted Patent: US 9,581,831 B2
• Time in Patent Office: Days
• US Class Current: 351/159.42
• CPC Class Codes: G02C 7/02 Lenses; Lens systems ; Methods of designing lenses
• CPC Class Codes: G02C 7/024 Methods of designing ophthalmic lenses
• CPC Class Codes: G02C 7/061 Spectacle lenses with progressively varying focal power
• CPC Class Codes: G02C 7/065 Properties on the principal line

Abstract

optical lens including, an object-side surface including an atoric surface element and an eyeball-side surface including an element that cancels a surface power shift produced by the atoric surface element, wherein the atoric surface element causes horizontal surface power at a fitting point to be greater than vertical surface power at the fitting point and causes a difference between the horizontal surface power and the vertical surface power to decrease along a horizontal reference line passing through the fitting point in a direction from the fitting point toward a periphery of the optical lens or causes a sign of the difference between the horizontal surface power and the vertical surface power to change along the horizontal reference line.

Claims

1. An optical lens comprising:

an object-side surface including an atoric surface element; and

an eyeball-side surface including an element that cancels a surface power shift produced by the atoric surface element,

wherein the atoric surface element causes horizontal surface power at a fitting point to be greater than vertical surface power at the fitting point and causes a difference between the horizontal surface power and the vertical surface power to decrease along a horizontal reference line passing through the fitting point in a direction from the fitting point toward a periphery of the optical lens or causes a sign of the difference between the horizontal surface power and the vertical surface power to change along the horizontal reference line.

2. The optical lens according to claim 1,

wherein the difference between the horizontal surface power and the vertical surface power at the fitting point is greater than or equal to 0.5 D but smaller than or equal to 3.5 D, where D represents dioptre.

3. The optical lens according to claim 1,

wherein an amount of decrease in the difference between the horizontal surface power and the vertical surface power is 0.3 D at maximum in an area within ±

10 mm from the fitting point along the horizontal reference line.

4. The optical lens according to claim 1,

wherein an amount of decrease in the difference between the horizontal surface power and the vertical surface power in an area within ±

25 mm from the fitting point along the horizontal reference line is greater than or equal to 0.3 times the difference between the horizontal surface power and the vertical surface power at the fitting point but smaller than or equal to 1.5 times of the difference between the horizontal surface power and the vertical surface power at the fitting point.

5. The optical lens according to claim 1,

further comprising a distance portion and a near portion having different power factors,

wherein the atoric surface element of the object-side surface includes at least one of the following elements:

an element where horizontal surface power is greater than vertical surface power of the distance portion along a principal meridian or a vertical reference line passing through the fitting point and an element where horizontal surface power is greater than vertical surface power of the near portion along the vertical reference line passing through the fitting point or the principal meridian.

6. The optical lens according to claim 5,

wherein the object-side surface includes any of the following elements:

a first element, a second element, and a third element,

the first element causes the vertical surface power of the distance portion to be greater than the vertical surface power of the near portion,

the second element causes the vertical surface power of the distance portion to be smaller than the vertical surface power of the near portion, and

the third element causes the vertical surface power of the distance portion to be equal to the vertical surface power of the near portion and the horizontal surface power of the distance portion to be equal to the horizontal surface power of the near portion.

7. A method for designing an optical lens having an object-side surface and an eyeball-side surface, the method comprising:

providing the object-side surface with an atoric surface element; and

providing the eyeball-side surface with an element that cancels a surface power shift produced by the atoric surface element of the object-side surface,

wherein the atoric surface element causes horizontal surface power at a fitting point to be greater than vertical surface power at the fitting point and the difference between the horizontal surface power and the vertical surface power to decrease along a horizontal reference line passing through the fitting point in a direction from the fitting point toward a periphery of the optical lens or the sign of the difference between the horizontal surface power and the vertical surface power to change along the horizontal reference line.