Light modulation element

• US 7,199,930 B2
• Filed: 06/13/2005
• Issued: 04/03/2007
• Est. Priority Date: 04/22/2005
• Status: Active Grant

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Sun, Yi-Ting, Yao, Po-Hung, Huang, Heng-Chun, Pao, Yu-Nan, Pan, I-Kai
• Primary Examiner(s): Ben; Loha
• Application Number:
  US11/150,101
• Publication Number:
  US 20060238874A1
• Time in Patent Office: 659 Days
• Field of Search: 359/619, 359621-625, 359/251, 359455-457, 359/566, 359/569, 359/599, 359/831, 359/741, 359/742, 362/31, 362/32, 362/302, 362/309, 362/318, 362/330, 362/333, 362/339, 349/10, 349/61, 349/62, 349/65, 349/112, 385/36, 385/43, 385/133, 385/146
• US Class Current: 359/619
• CPC Class Codes: G02B 3/0031 Replication or moulding, e.g. hot embossing, UV-casting, injection moulding
• CPC Class Codes: G02B 3/0043 Inhomogeneous or irregular arrays, e.g. varying shape, size, height
• CPC Class Codes: G02B 3/0062 Stacked lens arrays, i.e. refractive surfaces arranged in at least two planes, without structurally separate optical elements in-between
• CPC Class Codes: G02B 5/0226 having particles on the surface
• CPC Class Codes: G02B 5/0231 the surface having microprismatic or micropyramidal shape macroscopic prism arrays G02B5/045
• CPC Class Codes: G02B 5/0268 characterized by the fabrication or manufacturing method
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: G02B 5/045 Prism arrays
• CPC Class Codes: G02B 6/0051 Diffusing sheet or layer
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer
• CPC Class Codes: G02B 6/0065 Manufacturing aspects; Material aspects

Abstract

The present invention discloses a light modulation element, having a first optical surface and a second optical surface receiving an incident light, the light modulation element comprising: at least a transparent diffusion unit, for scattering the incident light, each being placed on the first optical surface; and at least a transparent collimation unit, for collimating the incident light, each being formed on top of the diffusion unit.

Claims

1. An light modulation element, having a first optical surface and a second optical surface for receiving an incident light, the light modulation element comprising:

at least a transparent diffusion unit, for diffusing the incident light, each being formed on the first optical surface; and

at least a transparent collimation unit, for collimating the incident light, each being superposed on the diffusion unit.

2. The light modulation element of claim 1, wherein the diffusion unit further comprises at least one semi-lenticular lens.

3. The light modulation element of claim 2, wherein the at least one semi-lenticular lens is characterized by a specific depth.

4. The light modulation element of claim 3, wherein the specific depth is in the range of 5 microns to 500 microns.

5. The light modulation element of claim 3, wherein a plurality of prisms is formed on top of each of at least one semi-lenticular lens.

6. The light modulation element of claim 1, wherein the collimation unit further comprises at least a prism.

7. The light modulation element of claim 6, wherein prism is characterized by a vertex angle and a height.

8. The light modulation element of claim 7, wherein the vertex angle is in the range of 30°

to 140°

.

9. The light modulation element of claim 7, wherein the height is in the range of 0 micron to 500 microns.

10. The light modulation element of claim 1, wherein the second optical surface is a smooth surface.

11. The light modulation element of claim 1, wherein the second optical surface is a rugged surface.

12. The light modulation element of claim 1, wherein the light modulation element is formed by a method comprising the steps of:

coating a layer of an UV curable material 52 on a flexible substrate 50;

rolling a roller 56 embossed with microstructures 54 on the layer of UV curable material 52 for patterning the UV curable material 52; and

curing the layer of UV curable material 52.

13. A luminance control apparatus, comprising:

a reflector;

a light guide plate, arranged over the reflector;

at least a light source, arranged at a side of the light guide plate for emitting an incident light; and

at least a light modulation element, arranged at a position over the light guide plate, each having a first optical surface and a second optical surface for receiving the incident light, each light modulation element further comprising;

at least a transparent diffusion unit, for diffusing the incident light, each being formed on the first optical surface; and

at least a transparent collimation unit, for collimating the incident light, each superposed on the diffusion unit.

14. The light modulation element of claim 13, wherein the diffusion unit further comprises:

at least a semi-lenticular lens, characterized by a specific depth.

15. The light modulation element of claim 13, wherein the collimation unit further comprises:

at least a prism, characterized by a vertex angle and a height.

16. The light modulation element of claim 13, wherein the second optical surface is a smooth surface.

17. The light modulation element of claim 13, wherein the second optical surface is a rugged surface.

18. The light modulation element of claim 13, comprising two light modulation elements, wherein the orientation of one of the two light modulation elements is being rotate by an angle in the range of 0°

to 90°

to be placed overlapping another light modulation element.

19. The light modulation element of claim 18, wherein the second optical surface is the rugged surface integrally formed with the light modulation element.

20. The light modulation element of claim 18, wherein the second optical surface is substantially the rugged surface coated on a surface of the light modulation element.