Microlens array substrate, method of manufacturing the same, and display device

• US 20030207484A1
• Filed: 04/04/2003
• Published: 11/06/2003
• Est. Priority Date: 05/11/1998
• Status: Active Grant

• Current Assignee: Takao Nishikawa
• Original Assignee: Takao Nishikawa
• Inventors: Nishikawa, Takao
• Granted Patent: US 6,909,121 B2
• Time in Patent Office: Days
• US Class Current: 438/31
• CPC Class Codes: G02B 3/0031 Replication or moulding, e.g. hot embossing, UV-casting, injection moulding

Abstract

The present invention provides a method of manufacturing a microlens array substrate comprising the steps of: closely providing a substrate precursor (30) between a first master mold (10) having a plurality of curved surfaces (12) and a second master mold (20) having a plurality of projections (22) to form a substrate (32) having a plurality of lenses (34) formed by the curved surfaces (12) and recesses (36) formed by the projections (22); removing the first and second master molds (10, 20) from the substrate (32); and filling the recesses (36) with a shading material (42) after the second master mold (20) is removed.

Claims

1. A method of manufacturing a microlens array substrate comprising the steps of:

closely providing a substrate precursor between a first master mold having a plurality of curved surfaces and a second master mold having a plurality of projections to form a substrate having a plurality of lenses formed by the curved surfaces and recesses formed by the projections;

removing the first and second master molds from the substrate; and

filling the recesses with a shading material after the second master mold is removed.

2. The method of manufacturing a microlens array substrate as defined in claim 1, wherein the substrate precursor is closely placed between the first and second master molds such that each of the projections avoids being positioned right above the center of each of the curved surfaces.

3. The method of manufacturing a microlens array substrate as defined in claim 1, further comprising a step of forming a protective film by placing a protective film precursor on at least one of the shading material in the recesses and the lenses, and by solidifying the protective film precursor.

4. The method of manufacturing a microlens array substrate as defined in claim 3,

wherein the protective film precursor is of a material which can be cured by applying energy.

5. The method of manufacturing a microlens array substrate as defined in claim 4,

wherein the energy is at least one of light and heat.

6. The method of manufacturing a microlens array substrate as defined in claim 5,

wherein the protective film precursor is a UV-curable resin.

7. The method of manufacturing a microlens array substrate as defined in any one of claims 3 to 6,

wherein the protective film precursor is solidified after placing a reinforcing plate on the protective film precursor.

8. The method of manufacturing a microlens array substrate as defined in any one of claims 1 to 6,

wherein the substrate precursor is of a material which can be cured by applying energy.

9. The method of manufacturing a microlens array substrate as defined in claim 8,

wherein the energy is at least one of light and heat.

10. The method of manufacturing a microlens array substrate as defined in claim 9,

wherein the substrate precursor is a UV-curable resin.

11. The method of manufacturing a microlens array substrate as defined in any one of claims 1 to 6,

wherein the recesses are filled with the shading material by an ink jet method.

12. The method of manufacturing a microlens array substrate as defined in any one of claims 1-6,

wherein at least part of an inner surface of each of the recesses is tapered such that an opening portion is wider than a bottom portion.

13. The method of manufacturing a microlens array substrate as defined in claim 12,

wherein only the opening portion of the inner surface is tapered.

19. A microlens array substrate manufactured by the method as defined in any one of claims 1 to 6.

14. A microlens array substrate comprising:

a plurality of lenses formed on one surface of the microlens array substrate;

a plurality of recesses formed on the other surface of the microlens array substrate such that each of the recesses avoids being positioned right above the center of each of the lenses; and

a shading layer formed in the recesses.

15. The microlens array substrate as defined in claim 14, further comprising a protective film on at least one of the lenses and the shading layer.

16. The microlens array substrate as defined in claim 15, further comprising a reinforcing plate on the protective film.

17. The microlens array substrate as defined in any one of claims 14 to 16,

wherein at least part of an inner surface of each of the recesses is tapered such that an opening portion is wider than a bottom portion.

18. The microlens array substrate as defined in claim 17,

wherein only the opening portion of the inner surface is tapered.

20. A display device comprising the microlens array substrate as defined in any one of claims 14 to 16, and a light source which emits light toward the microlens array substrate,

wherein the microlens array substrate is placed such that a surface on which the lenses are formed faces the light source.

21. The display device as defined in claim 20,

wherein the relation between the light refractive index “

na”

of the material forming the microlens array substrate and the light refractive index “

nb”

outside the lenses is “

na>

nb”

, when the lenses are convex lenses.

22. The display device as defined in claim 20,

wherein the relation between the light refractive index “

na”

of the material forming the microlens array substrate and the light refractive index “

nb”

outside the lenses is “

na<

nb”

, when the lenses are concave lenses.