Timepiece

• US 6,580,479 B1
• Filed: 03/15/1999
• Issued: 06/17/2003
• Est. Priority Date: 07/18/1997
• Status: Expired due to Fees

• Current Assignee: Citizen Holdings Co., Ltd.
• Original Assignee: Citizen Watch Co Limited (Citizen Electronics Company Limited)
• Inventors: Akiba, Yuichi, Akiyama, Takashi, Ide, Masafumi, Nakagawa, Koji, Kikuchi, Masami, Hoshino, Koichi, Toida, Takashi, Sekiguchi, Kanetaka
• Primary Examiner(s): PWU, JEFFREY C
• Application Number:
  US09/254,842
• Time in Patent Office: 1,555 Days
• Field of Search: 349/96, 349/113, 349/117, 349/142, 349/97, 349/98, 349/114, 349/115, 368/242, 368/84, 359/494, 359/495
• 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 having an hour hand and a minute hand, comprising:

an optical modulation section; and

a reflection-type polarizing film which has a function of reflecting light linearly polarized in a direction orthogonal to a transmission axis thereof,

wherein a member on which an information is formed is provided on a back side of said reflection-type polarizing film, and said optical modulation section varies a display state from a metallic shutter state covering the information on said member to a transmission state in which the information on said member is visible, in conjunction with said reflection-type polarizing film.

2. The timepiece according to claim 1, wherein said optical modulation section is provided with any one of an absorption-type polarizing film, a second reflection-type polarizing film, a color polarizing film, or a grid-type polarizing film in a rotatable manner in relation to said reflection-type polarizing film so as to make an angle between respective transmission axes thereof variable.

3. The timepiece according to claim 1, wherein said hour hand and said minute hand are disposed between said optical modulation unit and said reflection-type polarizing film.

4. The timepiece according to claim 2, wherein said hour hand and said minute hand are disposed between said optical modulation unit and said reflection-type polarizing film.

5. The timepiece according to claim 1, wherein

said optical modulation unit comprises a liquid crystal cell and one of an absorption-type polarizing film, a second reflection-type polarizing film and a color polarizing film, and

said optical modulation section varies said display state by varying a voltage applying state to said liquid crystal cell.

6. The timepiece according to claim 1, wherein

a dial is disposed on a back side of said hour hand and said minute hand, and

said optical modulation section and said reflection-type polarizing film are disposed on a front side of said dial.

7. The timepiece according to claim 1, wherein said optical modulation section and said reflection-type polarizing film are disposed on a back side of said hour hand and said minute hand.

8. The timepiece according to claim 1, wherein said optical modulation section and said reflection-type polarizing film are disposed on a front side of said hour hand and said minute hand.

9. The timepiece according to claim 6, wherein said optical modulation section and said reflection-type polarizing film are disposed on a front side of said hour hand and said minute hand.

10. The timepiece according to claim 1, further comprising a supplementary light source emitting light from a front side or a back side of said reflection-type polarizing film.

11. The timepiece according to claim 1, wherein said member on which an information is formed is a film on which photograph, character, figure or picture is formed.

12. The timepiece according to claim 1, wherein a power-generating element is provided on a back side of said reflection-type polarizing film.

13. The timepiece according to claim 12, wherein said optical modulation unit has a display area for displaying an amount of generated electricity of said power-generating element or an amount of accumulated electricity.

14. The timepiece according to claim 13, wherein

said display area comprises a reflection area and a transmission area, and

an area ratio between said reflection area and said transmission area is varied in accordance with said amount of generated electricity or said amount of accumulated electricity.

15. A timepiece according to claim 1, wherein a time display can be recognized in said full transmission state.