Display device and electronic timepiece

• US 6,385,139 B1
• Filed: 09/06/2000
• Issued: 05/07/2002
• Est. Priority Date: 01/13/1999
• Status: Expired due to Term

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Matsui, Tsuyoshi, Arikawa, Yasuo
• Primary Examiner(s): MISKA, VIT W
• Application Number:
  US09/623,626
• Time in Patent Office: 608 Days
• Field of Search: 368/82-84, 368/239-242, 349/61, 349/64, 349/68, 349/69, 349/80, 349/96, 349/97, 349/104, 349/113, 359/483, 359/487, 359/488, 359/497, 359/502
• US Class Current: 368/239
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133545 Dielectric stack polarisers
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 2203/02 reflective
• CPC Class Codes: G04G 9/0035 constructional

Abstract

A display device is provided which is able to effect high visibility display utilizing external light, and which is able to effect reflective display with a combination of various textures and color. The display device includes a first polarized-light separating member for transmitting a linearly polarized light component polarized in a first direction, a transmitted light polarization axis changing device capable of selecting states of changing and not changing a transmitted light polarization axis, a second polarized-light separating member for transmitting a linearly polarized light component in a polarized second direction and for mirror-reflecting a linearly polarized light perpendicular to the linearly polarized light component, and a reflecting element disposed in that order. Coloring layers or light-diffusing layers are formed on the surface or the back of the second polarized-light separating member.

Claims

1. A display device, comprising:

a first polarized-light separating member that transmits a linearly polarized light component polarized in a first direction of incident light and that does not transmit a linearly polarized light component polarized perpendicularly thereto;

a transmitted light polarization axis changing device that selects one of a first state of changing a transmitted light polarization axis and a second state of not changing the transmitted light polarization axis when incident linearly polarized light component is transmitted;

a second polarized-light separating member that transmits a linearly polarized light component polarized in a second direction of incident linearly polarized light components and that reflects a linearly polarized light component polarized in a third direction perpendicular to the second direction;

a reflecting element that reflects the linearly polarized light component transmitted by the second polarized-light separating member toward the second polarized-light separating member, the display device displaying predetermined information by first return light reflected by the reflecting element to be transmitted by the second polarized-light separating member, the transmitted light polarization axis changing device, and the first polarized-light separating member, and second return light reflected by the second polarized-light separating member to be transmitted by the transmitted light polarization axis changing device and the first polarized-light separating member of light incident on the first polarized-light separating member from an opposite side of the transmitted light polarization axis changing device; and

a modified layer that emits light incident on the second polarized-light separating member by changing optical characteristics formed on at least one of a surface of the second polarized-light separating member facing the transmitted light polarization axis changing device and a back of the second polarized-light separating member facing the reflecting element.

2. The display device according to claim 1, the modified layer being a surface-side modified layer formed on the surface of the second polarized-light separating member.

3. The display device according to claim 1, the modified layer being a back-side modified layer formed on the back of the second polarized-light separating member.

4. The display device according to claim 2, the modified layer comprising at least a coloring layer that emits light incident on the second polarized-light separating member by changing a hue.

5. The display device according to claim 2, the modified layer comprising at least a light-diffusing layer that defines and emits light incident on the second polarized-light separating member.

6. The display device according to claim 2, the modified layer being a composite layer comprising a coloring layer that emits light incident on the second polarized-light separating member by changing a hue and a light-diffusing layer that diffuses and emits light incident on the second polarized-light separating member.

7. The display device according to claim 1, the modified layer being formed as a surface-side modified layer and as a back-side modified layer on both the surface and the back of the second polarized-light separating member, and

the surface-side modified layer and the back-side modified layer mutually emitting light incident on the second polarized-light separating member by changing optical characteristics into different types.

8. The display device according to claim 7, each of the surface-side modified layer and the back-side modified layer comprising at least a surface-side coloring layer and a back-side coloring layer that emit light incident on the second polarized-light separating member by changing a hue into hues which differ from each other.

9. The display device according to claim 7, each of the surface-side modified layer and the back-side modified layer comprising at least a surface-side light-diffusing layer and a back-side light-diffusing layer that emit light incident on the second polarized-light separating member by changing the light into diffusion patterns which differ from each other.

10. The display device according to claim 7, at least one of the surface-side modified layer and the back-side modified layer being a composite layer comprising a coloring layer that emits light incident on the second polarized-light separating member by changing a hue, and a light-diffusing layer that diffuses and emits light incident on the second polarized-light separating member.

11. The display device according to claim 2, the surface-side modified layer being formed on an entire surface of the second polarized-light separating member.

12. The display device according to claim 2, the surface-side modified layer being formed only on a predetermined area on the surface of the second polarized-light separating member.

13. The display device according to claim 3, the back-side modified layer being formed on an entire back of the second polarized-light separating member.

14. The display device according to claim 3, the back-side modified layer being formed on a predetermined area in the back of the second polarized-light separating member.

15. The display according to claim 1, the reflecting element being a partial reflection optical element that reflects a part of an incident linearly polarized light component and that transmits other light, and the display device comprising a light source for backlight that emits light toward the reflecting element disposed between the second polarized-light separating member and the reflecting element at a position for sandwiching the reflecting element, and

the display device displaying predetermined information using a linearly polarized light component emitted from the light source for backlight and transmitted by the second polarized-light separating member, the transmitted light polarization axis changing device, and the first polarized-light separating member.

16. The display device according to claim 4, the coloring layer being one of a color filter layer and a dyeing layer attached to the second polarized-light separating member.

17. The display device according to claim 6, the light-diffusing layer being one of a corrugation formed on the second polarized-light separating member and a light-scattering coating film attached to the second polarized beam separation member.

18. The display device according to claim 1, said transmitted light polarization axis changing device comprising a liquid crystal device.

19. An electronic timepiece comprising the display device defined in claim 1, time and measurement results of time being displayed by an area in the transmitted light polarization axis changing device selected in a state of transmitting by changing the transmitted light polarization axis of the linearly polarized light transmitted by the first polarized-light separating member and by an area selected in a state of transmitting with no change.