Moving indicator for an analogue display device

Patent metadata

Field	Value
Publication number	US-11340557-B2
Application number	US-202017091163-A
Country	US
Kind code	B2
Filing date	Nov 6, 2020
Priority date	Dec 31, 2019
Publication date	May 24, 2022
Grant date	May 24, 2022

Abstract

A moving indicator for an analogue display device, in particular for a timepiece. The indicator includes a multi-layer part including an opaque metal layer and a transparent light guide layer and forming a body and a head of the indicator. The head is centred relative to a rotational axis of the indicator and arranged to receive a luminous flux on the bottom face thereof. A fluorescent material is arranged on the transparent light guide layer at the head of the indicator to absorb at least part of said luminous flux and to re-emit a second luminous fluorescence flux in the transparent light guide layer. Other aspects comprise a set of indicators, a display device and a watch comprising one or more moving indicators.

First claim

The invention claimed is:

1. A moving indicator for an analogue display device, in particular for a timepiece, comprising a multi-layer part including an opaque metal layer and a transparent light guide layer and forming a body and a head of the indicator, said head being centred relative to a rotational axis of the indicator and arranged to receive a luminous flux on the bottom face thereof, wherein a fluorescent material is arranged on or in the transparent light guide layer at the head of the indicator to absorb at least part of said luminous flux and to re-emit a second luminous fluorescence flux in the transparent light guide layer.

2. The indicator according to claim 1 , wherein the transparent light guide layer produces a total internal reflection of the luminous rays of the second luminous flux substantially perpendicular to said rotational axis.

3. The indicator according to claim 1 , wherein the multi-layer part comprises an optical isolation layer between the opaque metal layer and the transparent light guide layer, the Δn between the refractive index of the optical isolation layer and the refractive index of the transparent light guide layer lying in the interval 0.5 to 0.9, preferably in the interval 0.55 to 0.8, more preferably in the interval 0.6 to 0.75.

4. The indicator according to claim 3 , the optical isolation layer having a thickness that lies in the interval 2 μm to 15 μm, preferably in the interval 3 μm to 12 μm, more preferably in the interval 5 μm to 10 μm.

5. The indicator according to claim 1 , wherein the plurality of layers of the part are firstly deposited then stamped or cut to form the indicator.

6. The indicator according to claim 1 , wherein the part is flat, the top and bottom faces thereof being planar.

7. The indicator according to claim 1 , wherein said head includes a central hole wherein a sleeve made of an opaque material is arranged.

8. The indicator according to claim 1 , the indicator being a hand.

9. A set of indicators comprising at least a first indicator and a second indicator,
wherein said first and second indicators comprise a multi-layer part including an opaque metal layer and a transparent light guide layer and forming a body and a head of the indicator, said head being centred relative to a rotational axis of the indicator and arranged to receive a luminous flux on the bottom face thereof,
wherein a fluorescent material is arranged on or in the transparent light guide layer at the head of the indicator to absorb at least part of said luminous flux and to re-emit a second luminous fluorescence flux in the transparent light guide layer
wherein said head includes a central hole wherein a sleeve made of an opaque material is arranged,
and wherein said first indicator comprises one or more secondary holes arranged about the central hole of the head so as to allow said luminous flux to pass through the first indicator through the secondary holes so that at least part of said flux is absorbed by the fluorescent material of the second indicator when the first indicator and the second indicator are arranged such that the rotational axes of the first indicator and of the second indicator are aligned.

10. A display device for a timepiece, the device comprising:
a dial;
indicators, comprising a multi-layer part including an opaque metal layer and a transparent light guide layer and forming a body and a head of the indicator, said head being centred relative to a rotational axis of the indicator and arranged to receive a luminous flux on the bottom face thereof, wherein a fluorescent material is arranged on or in the transparent light guide layer at the head of the indicator to absorb at least part of said luminous flux and to re-emit a second luminous fluorescence flux in the transparent light guide layer, said indicators being disposed above the dial, the respective heads of the indicators being superimposed and fastened to respective arbors in order to rotate about a shared rotational axis; and
a stationary lighting source arranged to illuminate beneath all of the heads of the indicators by means of a luminous flux substantially parallel to the shared rotational axis and having a shorter wavelength than the wavelength re-emitted by the fluorescent material.

11. The device according to claim 10 , wherein the stationary lighting source includes electroluminescent diodes and/or organic electroluminescent diodes and/or miniature laser sources of the VCSEL type which are distributed about said arbors and mounted on a printed circuit component disposed beneath the dial.

12. A watch comprising a display device said display device comprising:
a dial;
indicators, comprising a multi-layer part including an opaque metal layer and a transparent light guide layer and forming a body and a head of the indicator, said head being centred relative to a rotational axis of the indicator and arranged to receive a luminous flux on the bottom face thereof, wherein a fluorescent material is arranged on or in the transparent light guide layer at the head of the indicator to absorb at least part of said luminous flux and to re-emit a second luminous fluorescence flux in the transparent light guide layer, said indicators being disposed above the dial, the respective heads of the indicators being superimposed and fastened to respective arbors in order to rotate about a shared rotational axis; and
a stationary lighting source arranged to illuminate beneath all of the heads of the indicators by means of a luminous flux substantially parallel to the shared rotational axis and having a shorter wavelength than the wavelength re-emitted by the fluorescent material, said indicators being hands.

Assignees

• Swatch Group Res & Dev Ltd

Inventors

• Tortora Pierpasquale

Classifications

• G02B6/0051

  Diffusing sheet or layer · CPC title

• G04B19/305

  the hands carrying the light source (hands and manufacture thereof G04B19/042; projection of hands or dials G04B19/34; illumination of scales and/or hands on moving scales H03J1/02; on compasses G01C17/24; on weighing apparatus G01G23/18; on measuring instruments G01D11/28) · CPC title

• G01D13/265

  Pointers which conduct light · CPC title

• G04B19/042 Primary

  Construction and manufacture of the hands; arrangements for increasing reading accuracy (hands with illumination G04B19/305; specially shaped hands, e.g. figures or pictures G04B45/0061; clockwork in the hands G04B45/043; invisible drive of the hands G04B45/046) · CPC title

• G01D11/28

  Structurally-combined illuminating devices · CPC title