Optical device and projection apparatus

• US 9,851,560 B2
• Filed: 08/05/2015
• Issued: 12/26/2017
• Est. Priority Date: 03/13/2015
• Status: Active Grant

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Chou, Ming-Chieh, Lee, Chi-Hung, Chen, Yi-Cheng
• Primary Examiner(s): HOWARD, RYAN D
• Application Number:
  US14/818,330
• Publication Number:
  US 20160266477A1
• Time in Patent Office: 874 Days
• Field of Search: 353 38, 359620, 359619, 359630, 359 13
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 27/48 Laser speckle optics
• 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

Abstract

An optical device including a first lens array is provided. The first lens array has micro-lens units arranged in an array. An outline of each of the micro-lens units is polygonal-shaped, circular or ellipsoidal. Moreover, a projection apparatus is also provided.

Claims

1. A projection apparatus, comprising:

a projection unit, emitting an image beam; and

a real image forming device, disposed on a transmitting path of the image beam, wherein the image beam forms an image on the real image forming device, and the real image forming device comprises;

a first lens array, having a plurality of micro-lens units, wherein the micro-lens units are arranged into an array, an outline of each of the micro-lens units is polygonal-shaped, circular, or ellipsoidal, and each of the micro-lens units comprises;

a first optical micro-structure, having the outline that is polygonal-shaped, circular, or ellipsoidal; and

a second optical micro-structure, wherein the first optical micro-structure surrounds the second optical micro-structure and is connected to the second optical micro-structure, and a shape of an outline of the second optical micro-structure is the same as or different from a shape of the outline of the first optical micro-structure; and

a second lens array, disposed beside the first lens array and having a plurality of columnar micro-lenses parallel to each other.

2. The projection apparatus as claimed in claim 1, wherein the first optical micro-structure has the polygonal-shaped outline, the shape of the outline of the second optical micro-structure is different from the shape of the outline of the first optical micro-structure, and the outline of the second optical micro-structure is circular or polygonal-shaped.

3. The projection apparatus as claimed in claim 2, wherein the first and second optical micro-structures protrude toward the same side.

4. The projection apparatus as claimed in claim 1, wherein a normal direction of a reference plane is parallel to an extending direction of each of the columnar micro-lenses, the reference plane takes a section of each of the columnar micro-lenses, a periphery of the section comprises a curved line, and a curvature radius of the curved line of one of the columnar micro-lenses is different from a curvature radius of the curved line of another of the columnar micro-lenses.

5. The projection apparatus as claimed in claim 1, wherein the columnar micro-lenses are arranged along a direction, each of the columnar micro-lenses has a width in the direction, and the width of one of the columnar micro-lenses in the direction is different from the width of another of the columnar micro-lenses in the direction.

6. The projection apparatus as claimed in claim 1, wherein a normal direction of a reference plane is parallel to an extending direction of each of the columnar micro-lenses, the reference plane takes a section of each of the columnar micro-lenses, and a periphery of the section comprises a portion of a curve, a portion of an ellipse, or a portion of a triangle.

7. The projection apparatus as claimed in claim 1, wherein each of the columnar micro-lenses has a convex surface.

8. The projection apparatus as claimed in claim 1, wherein each of the columnar micro-lenses has a first apex, each of the micro-lens unit has a second apex, a distance between the first apex of each of the columnar micro-lenses and the second apex of the corresponding micro-lens unit is D, a focal length of each of the columnar micro-lens is F1, and a focal length of each of the micro-lens units is F2, wherein F1≦

D≦

(30·

F1), F2≦

D≦

(30·

F2), or F1≦

D≦

(30·

F1) and F2≦

D≦

(30·

F2).

9. The projection apparatus as claimed in claim 1, wherein the real image forming device further comprises:

a third lens array, having a plurality of columnar micro-lenses parallel to each other, wherein the columnar micro-lenses of the second lens array are arranged along a first direction, the columnar micro-lenses of the third lens array are arranged along a second direction, and the first direction and the second direction are not parallel to each other.

10. The projection apparatus as claimed in claim 1, further comprising:

a virtual image forming unit, enlarging the image into a virtual image, wherein the virtual image forming unit comprises;

a concave lens, having a concave surface, wherein the concave surface partially reflects and partially transmits the image.

11. The projection apparatus as claimed in claim 10, wherein a periphery of the virtual image forming unit and a light field distribution of the image are rectangular.

12. The projection apparatus as claimed in claim 1, wherein the image beam is divided into a plurality of sub-image beams carrying different information, the sub-image beams are arranged along a first direction on the projection unit, the image is divided into a plurality of sub-images respectively formed by the sub-image beams, the sub-images are arranged along a second direction on the real image forming device, and the first direction and the second direction are not parallel to each other.

13. The projection apparatus as claimed in claim 1, wherein the first lens array further comprises:

a plurality of sub-micro-lens units, wherein an area of each of the sub-micro-lens units is smaller than an area of each of the micro-lens units, and the sub-micro-lens units are interspersed between the micro-lens units, wherein the outline of each of the sub-micro-lens units is circular.

14. The projection apparatus as claimed in claim 13, wherein the sub-micro-lens units are regularly or irregularly interspersed between the micro-lens units.

15. The projection apparatus as claimed in claim 13, wherein a ratio between an area of each of the micro-lens units and an area of the smallest sub-micro-lens unit of the sub-micro-lens units is greater than or equal to 3.

16. An optical device, comprising:

a first lens array, having a plurality of micro-lens units, wherein the micro-lens units are arranged into an array, an outline of each of the micro-lens units is polygonal-shaped, circular, or ellipsoidal, and each of the micro-lens units comprises;

a first optical micro-structure, having the outline that is polygonal-shaped, circular, or ellipsoidal; and

a second optical micro-structure, wherein the first optical micro-structure surrounds the second optical micro-structure and is connected to the second optical micro-structure, and a shape of an outline of the second optical micro-structure is the same as or different from a shape of the outline of the first optical micro-structure; and

a second lens array, disposed beside the first lens array and having a plurality of columnar micro-lenses parallel to each other.

17. The optical device as claimed in claim 16, wherein the first optical micro-structure has the polygonal-shaped outline, the shape of the outline of the second optical micro-structure is different from the shape of the outline of the first optical micro-structure, and the outline of the second optical micro-structure is circular or polygonal-shaped.

18. The optical device as claimed in claim 16, further comprising:

a third lens array, having a plurality of columnar micro-lenses parallel to each other, wherein the columnar micro-lenses of the second lens array are arranged along a first direction, the columnar micro-lenses of the third lens array are arranged along a second direction, and the first direction and the second direction are not parallel to each other.

19. The optical device as claimed in claim 16, wherein the first lens array further comprises:

a plurality of sub-micro-lens units, wherein an area of each of the sub-micro-lens units is smaller than an area of each of the micro-lens units, and the sub-micro-lens units are interspersed between the micro-lens units.

20. A projection apparatus, comprising:

a projection unit, emitting an image beam; and

a real image forming device, disposed on a transmitting path of the image beam, wherein the image beam forms an image on the real image forming device, and the real image forming device comprises;

a first lens array, having a plurality of micro-lens units, wherein the micro-lens units are arranged into an array, an outline of each of the micro-lens units is circular, and there is a circular hole inside each of the micro-lens units.

21. A projection apparatus, comprising:

a projection unit, emitting an image beam; and

a real image forming device, disposed on a transmitting path of the image beam, wherein the image beam forms an image on the real image forming device, and the real image forming device comprises;

a first lens array, having a plurality of micro-lens units, wherein the micro-lens units are arranged into an array, and an outline of each of the micro-lens units is polygonal-shaped, circular, or ellipsoidal; and

a second lens array, disposed beside the first lens array and having a plurality of columnar lenses parallel to each other.

22. The projection apparatus as claimed in claim 21, wherein the real image forming device further comprises:

a third lens array, having a plurality of columnar micro-lenses parallel to each other, wherein the columnar micro-lenses of the second lens array are arranged along a first direction, the columnar micro-lenses of the third lens array are arranged along a second direction, and the first direction and the second direction are not parallel to each other.