Time piece with power generation function

• US 6,937,301 B2
• Filed: 04/16/2002
• Issued: 08/30/2005
• Est. Priority Date: 07/18/1997
• Status: Expired due to Fees

• Current Assignee: Citizen Watch Co Limited (Citizen Electronics Company Limited)
• Original Assignee: Citizen Watch Co Limited (Citizen Electronics Company Limited)
• Inventors: Nakagawa, Koji, Akiba, Yuichi, Akiyama, Takashi, Ide, Masafumi, Kikuchi, Masami, Hoshino, Koichi, Toida, Takashi, Sekiguchi, Kanetaka
• Primary Examiner(s): PWU, JEFFREY C
• Application Number:
  US10/122,364
• Publication Number:
  US 20020109808A1
• Time in Patent Office: 1,232 Days
• Field of Search: 349 96- 98, 349113-115, 349/117, 349/142, 368/84, 368/242, 359/494, 359/498
• US Class Current: 349/96
• 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 1/13471 in which all the liquid crystal cells or layers remain transparent, e.g. FLC, ECB, DAP, HAN, TN, STN, SBE-LC cells G02F1/13475 takes precedence
• CPC Class Codes: G04G 9/0035 constructional
• CPC Class Codes: G04G 9/0082 by building-up characters using a combination of indicating elements and by selecting desired characters out of a number of characters or by selecting indicating elements the positions of which represents the time, i.e. combinations of G04G9/02 and G04G9/08

Abstract

A watch unit having a time-displaying section, including a reflection-type polarizing film 14 disposed on an upper portion or a lower portion of the time-displaying section or a portion comprising a part of the time-displaying section, an optical modulation section which varies the ratio of a transmission axis to a reflection axis of the reflection-type polarizing film 14, and a shutter function to shield a portion of or all of the watch unit having the time-display section by varying the reflection intensity and the transmission intensity in relation to the light incident direction using the reflection-type polarinzing film 14 and the optical modulation section, to enhance the appearance and to improve the versatility of the watch unit.

Claims

1. A timepiece with power generation function, comprising:

a reflection-type polarizing film which has a transmission axis and a reflection axis intersecting with the transmission axis at right angles, and a function of transmitting light linearly polarized in the direction parallel to the transmission axis but which reflects light linearly polarized in a direction parallel to the reflection axis;

an optical modulation section for modulating transmission of light, overlapping with said reflection-type polarizing film; and

a solar cell disposed on a back side of said reflection-type polarizing film and said optical modulation section.

2. The timepiece with power generation function according to claim 1, wherein said optical modulation unit comprises a liquid crystal panel, and said liquid crystal panel has a display area for displaying an amount of generated electricity of said solar cell or an amount of accumulated electricity.

3. The timepiece with power generation function according to claim 2, wherein said optical modulation section controls said display area in accordance with the amount of generated electricity of said solar cell or the amount of accumulated electricity.

4. The timepiece with power generation function according to claim 2, wherein said display area comprises a reflection area and a transmission area, and said optical modulation section varies an area ratio between said reflection area and said transmission area in accordance with the amount of generated electricity of said solar cell or the amount of accumulated electricity.

5. The timepiece with power generation function according to claim 1, wherein said optical modulation section varies a light incident on said solar cell by varying a ratio between incident light on the transmission axis of said reflection-type polarizing film and on the reflection axis thereof.

6. The timepiece with power generation function according to claim 1, wherein said optical modulation section varies reflection intensity and transmission intensity of said reflection-type polarizing film in accordance with an amount of generated electricity of said solar cell or an amount of accumulated electricity.

7. The timepiece with power generation function according to claim 2, wherein said display area is placed on a front side of said solar cell, and a light receiving condition of said solar cell is varied due to change in said display area caused by said optical modulation section.

8. The timepiece with power generation function according to claim 7, wherein said optical modulation section performs control such that transmittance of said display area becomes larger as an amount of generated electricity of said solar cell or an amount of accumulated electricity becomes smaller, and thereby intensifying light incident on said solar cell.

9. The timepiece with power generation function according to claim 2, wherein said reflection-type polarizing film is disposed on a back side of said liquid crystal panel.