Non-progressive multifocal ophthamic lenses

• US 4,869,588 A
• Filed: 05/04/1988
• Issued: 09/26/1989
• Est. Priority Date: 09/14/1987
• Status: Expired due to Fees

• Current Assignee: Opticorp, Inc.
• Original Assignee: Opticorp, Inc.
• Inventors: Walach, Michael, Frieder, Philip M.
• Primary Examiner(s): Sugarman, Scott J.
• Application Number:
  US07/190,149
• Time in Patent Office: 510 Days
• Field of Search: 351/168, 351/169, 351/170, 351/171, 351/172
• US Class Current: 351/168
• CPC Class Codes: G02C 7/06 bifocal; multifocal ; progressive G02C7/041 takes precedence

Abstract

The present invention relates to a multifocal ophtalmic lens which comprises a first substantially spherical area for distance viewing, a second substantially spherical area for near viewing having a desired width and height and being surrounded on a plurality of sides by the first area, and relatively narrow areas intermediate the first and second areas for blending the second area into the first area. The lens design of the present invention may also include an optional third substantially spherical area adjacent the second area for increasing the near viewing range in a substantially contiguous manner.

Claims

1. A non-progressive multifocal ophthalmic lens which comprises a first substantially spherical, clear area for distance viewing, a second substantially spherical, clear area for near viewing, said second area having a desired width and depth and being surrounded on a plurality of sides by said first area, and areas intermediate said first and second areas for blending said second area into said first area, said lens being characterized by substantially no image jump.

2. A lens in accordance with claim 1 wherein said second area has a substantially flat top portion.

3. A lens in accordance with claim 2 wherein said second area is surrounded on at least three sides by said first area.

4. A lens in accordance with claim 3 which further comprises a third substantially spherical, clear area for intermediate viewing, said third area lying adjacent said second area and forming with said second area a substantially contiguous range of near vision.

5. A lens in accordance with claim 4 wherein said third area has a substantially flat top portion and is surrounded by said first area on at least three sides, said third area being blended into said first area.

6. A lens in accordance with claim 4 wherein said second and third areas each have a width in the range of from about 18 mm to about 45 mm.

7. A lens in accordance with claim 5 wherein said blending areas do not extend to the edges of said lens so as to minimize distortion.

8. A lens in accordance with claim 7 wherein said blending areas are each formed by sinusoidal curves and each have a width less than about 10 mm.

9. A lens in accordance with claim 4 wherein said second and third area are angled nasalward.

10. A lens in accordance with claim 4 wherein each of said first, second and third areas is defined by an arc, and a portion of said arc defining said first area coincides with a portion of said arc defining said third area and a portion of said arc defining said third area coincides with a portion of said arc defining said second area.

11. A lens in accordance with claim 10 wherein said first area has a central axis with its center lying along said axis and said second and third areas each having a center lying below said axis.

12. A non-progressive bifocal ophthalmic lens which comprises:

a first substantially spherical, clear area for distance viewing;

said first area being defined by a first arc having a first radius;

a second substantially spherical, clear area for near viewing;

said second area having a desired width and height and being surrounded on a plurality of sides by said first area;

said second area being defined by a second arc having a second radius different from said first radius;

said first and second areas coinciding for some distance and thereby negating any need to blend a first portion of said second area into said first area; and

areas intermediate said first and second areas for blending said second area into said first area where said first and second arcs do not coincide,

said lens being characterized by the absence of substantially any image jump.