Reflection type display apparatus, reflection type display apparatus manufacturing method, and electronic appliance using the same

• US 6,774,964 B2
• Filed: 12/27/2001
• Issued: 08/10/2004
• Est. Priority Date: 12/28/2000
• Status: Expired due to Fees

• Current Assignee: Omron Corporation
• Original Assignee: Omron Corporation
• Inventors: Aoyama, Shigeru, Ikeda, Masaaki, Shinohara, Masayuki, Matsushita, Motohiko, Funamoto, Akihiro
• Primary Examiner(s): Nguyen, Dung T.
• Assistant Examiner(s): Duong, Thoi V.
• Application Number:
  US10/035,032
• Publication Number:
  US 20020085150A1
• Time in Patent Office: 957 Days
• Field of Search: 349/113-142, 349/67, 349/61, 349/62, 349/63
• US Class Current: 349/113
• CPC Class Codes: G02F 1/133553 Reflecting elements associated to illuminating devices G02F1/133605
• CPC Class Codes: G02F 1/133616 Front illuminating devices

Abstract

In a reflection type display apparatus in which a forward lightening apparatus is arranged in front of a reflection type display panel, lowering of contrast occurred when the forward lightening apparatus is turned ON is prevented. In this reflection type display apparatus, the forward lightening apparatus is adhered via an adhesive layer to a front surface of the reflection type display panel having a reflection plane. The reflection plane is constituted by a large number of first very fine patterns having a spherical shape, and a large number of second very fine patterns whose front surfaces are inclined. External light which is vertically entered into the front surfaces is reflected by the first patterns, and thereafter, the reflected external light is projected as a display along a forward direction. The forward lightening apparatus is arranged by providing a light source on a side surface of a light conducting plate having a wedge shape. The light is obliquely projected from a rear surface of the light conducting plate to the reflection type display panel. The light which is obliquely projected from the forward lightening apparatus to the reflection type display panel is reflected by the second patterns, and thereafter, is projected along the substantially same directions as reflection light of the external light.

Claims

1. A reflection type display apparatus comprising:

a reflection type display panel having a reflection plane used to reflect thereon light entered from a forward direction; and

a forward lightening apparatus arranged in front of said reflection type display panel;

wherein;

light which is entered from said forward lightening apparatus into said reflection type display panel is entered into said reflection type display panel along a direction different from a direction of external light entered into said reflection type display panel;

both the light which is derived from said forward lightening apparatus and is reflected on said reflection plane, and said external light which is reflected on said reflection plane are projected along the substantially same reflection direction; and

said reflection plane is subdivided into both a first region capable of reflecting thereon light which is obliquely entered from said forward lightening apparatus along said reflection direction, and a second region capable of reflecting thereon external light which is entered at a substantially right angle along said reflection direction,

wherein the first region accounts for a smaller portion of the reflection plane than the second region.

2. A reflection type display apparatus as claimed in claim 1 wherein:

said reflection plane is comprised of;

a first region on which a concave/convex pattern is formed, said concave/convex pattern reflecting thereon light which is obliquely entered from said forward lightening apparatus along said reflection direction; and

a second region on which another concave/convex pattern is formed, said concave/convex pattern reflecting thereon external light which is entered at a substantially right angle along said reflection direction.

3. A reflection type display apparatus as claimed in claim 1 wherein:

said reflection plane owns substantially no such a region located in parallel to a front surface of said reflection type display panel.

4. A reflection type display apparatus as claimed in claim 2 wherein:

a normal line stood on an averaged inclined plane of said concave/convex pattern formed on said first region is inclined from a direction perpendicular to the reflection plane toward a light source direction of said forward lightening apparatus.

5. A reflection type display apparatus as claimed in claim 1 wherein:

both a luminance center of light which is derived from said forward lightening apparatus and is reflected on said reflection plane, and another luminance center of external light which is reflected on said reflection plane are collected at a predetermined position in front of said reflection type display panel.

6. A reflection type display apparatus as claimed in claim 1 wherein:

said forward lightening apparatus is comprised of;

a light source for projecting light; and

a light conducting plate for confirming incident light in the own light conducting plate and for propagating said confined light through the own light conducting plate.

7. A reflection type display apparatus as claimed in claim 1 wherein:

said forward lightening apparatus is comprised of;

a light source for projecting light; and

a directivity controlling unit for controlling directivity of light projected from said light source.

8. A reflection type display apparatus as claimed in claim 6 wherein:

a thickness of an edge portion of said light conducting plate, which is located far from said light source, is made thinner than a thickness of a portion of said light conducting plate, which is located in the vicinity of said light source.

9. A reflection type display apparatus as claimed in claim 8 wherein:

both a front surface and a rear surface of said light conducting plate are formed under smooth condition.

10. A reflection type display apparatus as claimed in claim 6 wherein:

a front surface of said light conducting plate is made smooth; and

a pattern inclined in such a manner that a thickness of said light conducting plate on the side located far from said light source becomes thin is repeatedly formed on a rear surface of said light conducting plate.

11. A reflection type display apparatus as claimed in claim 6 wherein:

a rear surface of said light conducting plate is optically adhered to said reflection type display panel; and

a low refractive index layer is formed between said light conducting plate and said reflection type display panel, the reflective index of said low refractive index layer being larger than a refractive index of air and smaller than a refractive index of said light conducting plate.

12. A reflection type display apparatus as claimed in claim 11 wherein:

a thickness of said light conducting plate becomes thin in accordance with a position where said light conducting plate reaches close to said light source within a region close to the light source.

13. A method for manufacturing the reflection type display apparatus recited in claim 1, wherein:

ultraviolet hardening type resin is supplied onto a board; and

under such a condition that said ultraviolet hardening type resin is sandwiched between a stamper having an inverted pattern of a reflection plane and said board, ultraviolet rays are irradiated to said ultraviolet hardening type resin so as to harden the ultraviolet hardening type resin, and then to transfer the inverted pattern of said stamper to said ultraviolet hardening type resin.

14. A method for manufacturing the reflection type display apparatus recited in claim 1, wherein:

under such a condition that resin supplied onto a board has not yet been hardened, or is softened, said resin is sandwiched between a stamper having an inverted pattern of a reflection plane and said board and then is depressed so as to transfer the inverted pattern of said stamper to said resin.

15. A reflection type display apparatus as claimed in claim 1 wherein:

while liquid crystal is sealed within said reflection type display panel, said liquid crystal display panel produces an image by utilizing a characteristic of said sealed liquid crystal.

16. A portable telephone comprising:

a dial unit for setting a transmission destination; and

a display unit with employment of the reflection type display apparatus recited in claim 1.

17. A portable information terminal comprising:

an input unit used to input data, or a command; and

a display unit with employment of the reflection type display apparatus recited in claim 1.

18. A portable type computer comprising:

input/output means; and

a display unit with employment of the reflection type display apparatus recited in claim 1.

19. A television comprising:

turning means; and

a display unit with employment of the reflection type display apparatus recited in claim 1.

20. An electronic appliance comprising:

a display unit with employment of the reflection type display apparatus recited in claim 1; and

an electronic circuit connected to said display unit.

21. In a light reflecting method of a reflection type display apparatus equipped with a reflection type display panel having a reflection plane used to reflect thereon light entered from a forward direction, and a forward lightening apparatus arranged in front of said reflection type display panel, said light reflecting method comprising:

a step for entering light which is entered from said forward lightening apparatus into said reflection type display panel into said reflection type display panel along a direction different from a direction of external light entered into said reflection type display panel; and

a step for projecting both the light which is derived from said forward lightening apparatus and is reflected on said reflection plane, and said external light which is reflected on said reflection plane along the substantially same reflection direction, wherein said reflection plane is subdivided into both a first region capable of reflecting thereon light which is obliquely entered from said forward lightening apparatus along said reflection direction, and a second region capable of reflecting thereon external light which is entered at a substantially right angle along said reflection direction;

wherein the first region accounts for a smaller portion of the reflection plane than the second region.