Lens array

• US 7,952,809 B2
• Filed: 07/10/2007
• Issued: 05/31/2011
• Est. Priority Date: 07/10/2006
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Takai, Yuichi
• Primary Examiner(s): Spector; David N
• Application Number:
  US12/306,909
• Publication Number:
  US 20090268303A1
• Time in Patent Office: 1,421 Days
• Field of Search: 359/290, 359/297, 359/665, 359/666, 359/721, 359/886
• US Class Current: 359/666
• CPC Class Codes: G02B 26/005 based on electrowetting
• CPC Class Codes: G02B 3/0056 arranged along two different directions in a plane, e.g. honeycomb arrangement of lenses G02B3/0043 takes precedence; miniaturised objectives for electronic devices employing wafer level optics G02B13/0085
• CPC Class Codes: G02B 3/14 of variable focal length

Abstract

A lens array capable of making the characteristics of lens elements uniform is provided. A lens array 10 according to the present invention includes first liquid 11 that is conductive, second liquid 12 that is insulative and that has a refractive index different from that of the first liquid, and a plurality of lens elements 13 forming lens surfaces 13A at an interface between the first liquid 11 and the second liquid 12. The lens surfaces 13A of the lens elements 13 reversibly vary in accordance with output control of an applied voltage. The lens array is structured such that the adjacent lens elements 13 liquidly communicate with each other, whereby differences in the amounts of the first liquid 11 and the second liquid 12 between the lens elements can be avoided and the lens characteristics can be made uniform.

Claims

1. A lens array comprising:

a first liquid that is conductive;

a second liquid that is insulative and that has a refractive index different from that of the first liquid; and

a plurality of lens elements having lens surfaces at an interface between the first liquid and the second liquid,

wherein the lens surfaces of the lens elements reversibly vary in accordance with output control of an applied voltage, and

wherein the lens array is characterized in that horizontally adjacent lens elements are separated by a barrier and fluid channels are provided between the adjacent lens elements respectively providing transfer of the first liquid and the second liquid between the adjacent lens elements.

2. The lens array according to claim 1, characterized in that

the lens elements are two-dimensionally arranged in a liquid chamber formed between a common substrate and a lid body that faces the common substrate, and

at least one of the first liquid and the second liquid communicates between the adjacent lens elements with respect to each other.

3. The lens array according to claim 2, characterized in that

a perforated plate is disposed in the liquid chamber, the perforated plate forming passages that allow liquid communication at least between the perforated plate and the common substrate, and

the lens elements are sectioned by an opening-free portion of the perforated plate.

4. The lens array according to claim 3, characterized in that

openings in the perforated plate have a circular shape.

5. The lens array according to claim 3, characterized in that

at least peripheral portions of the openings in the perforated plate are formed of a conductive body, and the peripheral portions of the openings are covered with a water repellent film.

6. The lens array according to claim 2, characterized in that

a liquid inlet that guides the first liquid and the second liquid to the inside of the liquid chamber from the outside and a liquid outlet that discharges the first liquid and the second liquid to the outside of the liquid chamber from the inside are provided between the common substrate and the lid body.

7. The lens array according to claim 1, characterized in that

the lens elements are sectioned by a plurality of projections provided so as to stand upright on the common substrate.

8. The lens array according to claim 7, characterized in that

the projections are rod-shaped projections disposed at four corners of each of the lens elements.

9. The lens array according to claim 7, characterized in that

the projections are linear projections which are disposed between the adjacent lens elements and in which passages for allowing liquid communication between the adjacent lens elements are formed.

10. The lens array according to claim 7, characterized in that

a distance between the adjacent projections is set equal to or less or less than a capillary length.

11. The lens array according to claim 7, characterized in that

surfaces of the projections are covered with a transparent electrode film, and a surface of the transparent electrode film is covered with a water repellent film.