Wafer level lens system and method of fabricating the same

Patent metadata

Field	Value
Publication number	US-10175462-B2
Application number	US-201514807454-A
Country	US
Kind code	B2
Filing date	Jul 23, 2015
Priority date	Jul 23, 2015
Publication date	Jan 8, 2019
Grant date	Jan 8, 2019

Abstract

A wafer level lens system includes a target lens and a wafer level lens group. The target lens includes a first surface, a second surface, and a first fitting structure. The second surface is opposite to the first surface. The first fitting structure is disposed at the second surface. The wafer level lens group includes a first transparent plate and a second fitting structure. The first transparent plate has a third surface and a fourth surface opposite to the third surface. The second fitting structure is disposed on the third surface. The first fitting structure is fitted into the second fitting structure, and there is a space encapsulated between the second surface and the third surface.

First claim

What is claimed is:

1. A wafer level lens system, comprising:
a monolithic lens having a first surface and a second surface opposite to the first surface, wherein each of the first surface and the second surface comprises a curved surface, and the monolithic lens is a single piece of continuous material and comprises:
a first fitting structure disposed at least at the second surface; and
a composite wafer level lens group comprising:
a first transparent plate having a third surface and a fourth surface opposite to the third surface, wherein the third surface and the fourth surface are planar; and
a second fitting structure, which is a material layer covering the entire third surface of the first transparent plate, wherein the first fitting structure is fitted into the second fitting structure, such that the monolithic lens and the composite wafer level lens group are fixed to each other, and there is a space encapsulated between the second surface and the third surface.

2. The wafer level lens system of claim 1 , wherein the first surface comprises a convex aspheric surface, and the second surface comprises a concave aspheric surface.

3. The wafer level lens system of claim 2 , wherein the first fitting structure comprises a flange surrounding the concave aspheric surface, the second fitting structure comprises a recess, and the flange is fitted into the recess.

4. The wafer level lens system of claim 3 , wherein a sidewall of the recess is in contact with the concave aspheric surface of the second surface.

5. The wafer level lens system of claim 3 , wherein the second fitting structure comprises a flat portion surrounded by the recess, and the flat portion is fitted into the concave aspheric surface.

6. The wafer level lens system of claim 5 , wherein the space is disposed between a concave aspheric surface of the second surface and the flat portion.

7. The wafer level lens system of claim 5 , wherein the second fitting structure comprises a first lens structure surrounded by the flat portion.

8. The wafer level lens system of claim 1 , wherein the monolithic lens is made of a reflowable material.

9. The wafer level lens system of claim 1 , wherein the composite wafer level lens group comprises a second lens structure disposed on the fourth surface.

10. The wafer level lens system of claim 1 , wherein the composite wafer level lens group comprises:
a second transparent plate having a fifth surface and a sixth surface opposite to the fifth surface, wherein the second transparent plate is disposed on a side of the first transparent plate opposite to the monolithic lens; and
a spacer disposed between an edge of the fourth surface and an edge of the fifth surface to form a lens group space therebetween.

11. The wafer level lens system of claim 10 , wherein the composite wafer level lens group comprises a third lens structure and a fourth lens structure, the third lens structure is disposed on the fifth surface, and the fourth lens structure is disposed on the sixth surface.

12. The wafer level lens system of claim 1 , wherein the space is filled with air.

13. A method for fabricating a wafer level lens system, comprising:
disposing an imprintable material layer on a first surface of a transparent plate, wherein the first surface of the transparent plate is planar;
producing an imprint in the imprintable material layer to form a first fitting structure on the first surface of the transparent plate and covering the entire first surface of the transparent plate;
hardening the first fitting structure to form at least one first composite wafer level lens group comprising the transparent plate and the first fitting structure; and
fitting a second fitting structure of a monolithic lens into the first fitting structure such that the monolithic lens and the first composite wafer level lens group are fixed to each other, wherein the monolithic lens is a single piece of continuous material and has a first surface and a second surface opposite to the first surface, wherein each of the first surface and the second surface comprises a curved surface.

14. The method of claim 13 , wherein the imprinting process is performed by applying a surface of a master to the imprintable material layer.

15. The method of claim 13 , wherein the number of the first composite wafer level lens group is plural, and the method further comprising:
separating the first composite wafer level lens groups.

16. The method of claim 13 , wherein the first fitting structure comprises a recess, and the bonding process is performed by attaching a sidewall of the recess to a concave aspheric surface of the monolithic lens.

17. The method of claim 13 , wherein the monolithic lens is formed by a molding process comprising:
forming a mold cavity having dimensions substantially the same as the monolithic lens between at least two molds;
injecting a lens-forming fluid into the mold cavity;
hardening the lens-forming fluid within the mold cavity to form the monolithic lens; and
separating the monolithic lens from the molds.

18. The method of claim 13 , wherein the monolithic lens is formed by an imprinting process.

Assignees

• Himax Tech Ltd

Inventors

• Lu Yin-Dong
• Lin Han-Ching

Classifications

• G02B13/0035

  having three lenses · CPC title

• B29D11/00307

  Producing lens wafers · CPC title

• G02B13/004

  having four lenses · CPC title

• G02B3/0075

  characterized by non-optical structures, e.g. having integrated holding or alignment means · CPC title

• B29D11/0073

  Optical laminates · CPC title