Watch including a device for measuring the degree of relative humidity inside the watch case

Patent metadata

Field	Value
Publication number	US-11256217-B2
Application number	US-201916454163-A
Country	US
Kind code	B2
Filing date	Jun 27, 2019
Priority date	Jul 20, 2018
Publication date	Feb 22, 2022
Grant date	Feb 22, 2022

Abstract

A watch including a watch case, wherein the watch case includes a device for measuring the degree of humidity inside the watch, wherein the device for measuring the degree of humidity is a fibre optic device including a measuring optical fibre, the measuring optical fibre includes a portion configured such that the refractive index of said portion changes in the presence of water vapour inside the watch case.

First claim

The invention claimed is:

1. A watch comprising a watch case, wherein the watch case comprises a device for measuring a degree of relative humidity inside the watch;
wherein said device for measuring the degree of relative humidity is a fibre optic device including a measuring optical fibre, said optical fibre including a portion configured such that a refractive index of said portion changes in a presence of water vapour inside the watch case.

2. The watch according to claim 1 , wherein said portion forms an intermediate part of the measuring optical fibre, located between two ends of the optical fibre.

3. The watch according to claim 1 , wherein said portion forms a free end of the optical fibre, said free end being optically configured to form a Fabry-Pérot cavity.

4. The watch according to claim 3 , wherein said device for measuring the degree of relative humidity further includes a light input optical fibre, a light output optical fibre, and an optical coupler coupling the light input optical fibre to the light output optical fibre; another end of the measuring optical fibre being connected to the optical coupler.

5. The watch according to claim 1 , wherein said portion of the measuring optical fibre is stripped of its optical sheath.

6. The watch according to claim 5 , wherein said portion of the measuring optical fibre includes an external layer whose refractive index changes in the presence of water vapour.

7. The watch according to claim 6 , wherein said external layer includes an alternate superposition of layers of polymers and of silicon dioxide nanoparticles.

8. The watch according to claim 5 , wherein said portion of the measuring optical fibre has a length substantially equal to 30 mm.

9. The watch according to claim 1 , wherein said watch case is provided with a case middle and further includes a light transmission window.

10. The watch according to claim 9 , wherein said light transmission window is machined in the case middle.

11. The watch according to claim 10 , wherein said light transmission window is formed of a translucent water resistant material.

12. The watch according to claim 10 , wherein said device for measuring the degree of relative humidity is arranged inside the case middle of the watch case, respective free ends of light input and output optical fibres being arranged facing the light transmission window.

13. The watch according to claim 10 , wherein said device for measuring the degree of relative humidity is arranged inside the case middle of the watch case, two ends of the measuring optical fibre being arranged facing the light transmission window.

14. The watch according to claim 9 , wherein said watch case contains a dial and is provided with a crystal closing the case middle; the light transmission window being machined through the dial and being arranged facing the crystal.

15. The watch according to claim 14 , wherein said light transmission window is formed of an aperture made through the dial.

16. An assembly for measuring the degree of relative humidity inside a watch, comprising a watch and a device equipped with means for determining a degree of relative humidity from a light signal and light emitting and receiving means connected to the determining means, wherein said watch conforms to claim 9 , the device being configured to emit and receive light through the light transmission window of the watch, the light flowing through the measuring optical fibre.

17. The assembly according to claim 16 , wherein said device is a portable device.

18. The assembly according to claim 17 , wherein said portable device has a pen shape.

19. The assembly according to claim 16 , wherein said light emitting and receiving means include a focused light source and a light sensor.

20. The assembly according to claim 16 , wherein said device further comprises an electronic relative humidity sensor, and means of comparison between a relative humidity value determined by the electronic relative humidity sensor and a relative humidity value determined with a degree of relative humidity from a light signal.

21. The assembly according to claim 20 , wherein said device further includes display means able to display several distinct visual signals as a function of a result of the comparison, each visual signal corresponding to a predetermined differential value of relative humidity.

Assignees

• Swatch Group Res & Dev Ltd

Inventors

• Tortora Pierpasquale

Classifications

• G01N2021/458

  using interferential sensor, e.g. sensor fibre, possibly on optical waveguide · CPC title

• G04B47/06 Primary

  with attached measuring instruments, e.g. pedometer, barometer, thermometer or compass {(in combination with a tachometer which winds up the clockwork G04B5/206)} · CPC title

• G01D5/35332

  using other interferometers · CPC title

• G04D7/004 Primary

  Optical measuring and testing apparatus · CPC title

• G04D7/007

  with regard to the sealing of the case · CPC title