CH708838B1 - Display set with a hidden display under a semi-reflective element. - Google Patents

Abstract

The present invention relates to a display assembly (10) comprising a display module provided with an electronic display (31) and a light source and a dial module (20) for displaying the display only when the display module ci is activated, characterized in that the dial module (20) comprises a dial (21) translucent or semi-transparent under which is disposed a semi-reflective element (22). The display assembly (10) can be used in a timepiece.

Description

Description: [0001] The present invention relates to a display assembly comprising a display comprising a light source and a semi-transparent element making it possible to show the display only when the latter is activated.

PRIOR ART [0002] It is known in the prior art for electronic needle watches. These needle watches can be equipped with an LCD-type electronic display to display additional information. This additional information may be the date or time on a second time zone or any other information that can be displayed by an electronic watch.

[0003] Generally, the dial of this watch is a plastic or metal dial. This dial has an opening so that the display can be seen by the user. For example, the LCD display will be pasted on the underside of the dial to be attached to it.

To improve the aesthetics of the dial, it can be made of mother-of-pearl. However, the presence of an opening for the LCD display spoils the esthetic contribution of mother-of-pearl.

To overcome this drawback, an idea is to provide a display assembly 1 which consists in arranging the display 4 and its electronic circuit 3 under the dial 2, the latter having no opening. For an electronic display hidden under a dial, a semi-transparent dial is needed. Such a semitransparent dial allows in a first mode of use to camouflage the movement so that only the dial and its decoration are perceptible when the display is off, and in a second mode of use, to allow reading through the electronic display when it is switched on.

In order to camouflage the movement and the display in off mode, it is envisaged to use a dial that will absorb the light or diffuse it so that the user can not see through the dial. Thus, it is envisaged to use a piece of fine mother-of-pearl (between 0.01 and 1 mm thick). This piece of fine mother-of-pearl is aesthetically interesting and translucent; it transmits light while diffusing it. This diffusion property makes it possible to hide the display and the movement; the larger the diffusion, the clearer the dial will look.

On the other hand, when the display is on, it is preferable that the dial is as transparent as possible in order to transmit a higher luminance of the display to promote the contrast necessary for a good reading.

In addition, it is preferable to have the dial having the least possible diffusion to maintain the fineness of the illuminated details of the display placed under the dial. Thus, the more the mother-of-pearl piece will be diffusing and the poorer the display will appear.

There is therefore a compromise to be made on the piece of mother-of-pearl to have a balance between deformation of the image and whiteness of the dial.

An example of a parameter that can be modified is the thickness of the mother of pearl which makes it possible to adapt the diffusion property in order to make mother-of-pearl clearer. If it is too light, that is to say, too thin, the electronic display can be visible when it is off and the mother-of-pearl appears dark as shown in fig. 1b. In return, if the mother of pearl thickness is too large as shown in FIG. 1a, the dial is more beautiful because the mother of pearl appears brighter but the image of the display will be too deformed.

Therefore, it is extremely difficult to have a mother of pearl dial under which a display can be placed without disturbing the aesthetics and readability of the information of the display. SUMMARY OF THE INVENTION [0012] To this end, the invention proposes to solve the drawbacks of the prior art by providing a display assembly in which an electronic display is hidden under a dial when said display is off, but allowing the information provided by said display to be perfectly readable and accurate when said display is turned on.

The invention relates to a display assembly comprising a display module provided with an electronic display and a light source for displaying at least one information and a dial module for displaying said information of the display only. when it is activated, characterized in that the dial module comprises a dial made of a translucent or semi-transparent material under which is disposed a semi-reflective element.

In a first advantageous embodiment, the semi-reflective element comprises a metal layer directly deposited on said dial.

In a second advantageous embodiment, the semi-reflective element comprises a metal layer deposited on a flexible film.

In a third advantageous embodiment, the semi-reflective element comprises a dielectric mirror in the form of a film.

In a fourth advantageous embodiment, the semi-reflecting element comprises a dielectric mirror directly made on said dial, a film being glued over to stiffen said dial.

In a fifth advantageous embodiment, said dielectric mirror is composed of a plurality of layers of stacked dielectric materials having refractive indices and different thicknesses.

In another advantageous embodiment, said dielectric mirror is composed of a plurality of layers of birefringent dielectric materials.

In another advantageous embodiment, the film is a flexible film.

In another advantageous embodiment, the film is a rigid film.

In another advantageous embodiment, the thickness of the dial module is between 0.3 and 0.5 mm.

In another advantageous embodiment, the thickness of the dial is between 0.01 and 0.4 mm.

In another advantageous embodiment, the display assembly further comprises an opaque film located between the display module and the dial module.

In another advantageous embodiment, the dial is made of a material included in the list comprising: mother-of-pearl, amber, meteorites, horn, bone, leather, skin, coral, cartilage, semi-transparent minerals (silica, calcite), semi-transparent or tinted glasses, ceramics (oxides, carbides, nitrides, borides) or wood.

The present invention also relates to a timepiece which comprises a display assembly according to the invention or one of the advantageous embodiments of the invention.

BRIEF DESCRIPTION OF THE FIGURES The objects, advantages and features of the display assembly according to the present invention will become more clearly apparent in the following detailed description of at least one embodiment of the invention given solely as a nonlimiting example and illustrated by the accompanying drawings in which: FIGS. 1a and 1b show schematically the display assembly according to the prior art.

Fig. 2 schematically shows the display assembly according to the invention.

Detailed Description [0028] FIG. 2 shows a display assembly 10 according to the present invention. This display assembly 10 is arranged in a housing of a portable object such as a watch. It can also be imagined that this display assembly is arranged in a jewelery article such as a bracelet.

The display assembly 10 comprises a dial module 20 and a display module 30. The display module 30 comprises an electronic display 31 carried by a platen. This electronic display 31 is a display or digital screen. This display 31 can use LCD technology, or LED, or OLED. LED or OLED technologies have the advantage of being their own source of light for having emitting displays. For LCD technology, a backlight is used. For an LED electronic display 31, it comprises a substrate serving as a circuit 32 on which the light-emitting diodes (LEDs) are soldered and a separator 33 to improve the distinction of the details of the information displayed by the light-emitting diodes. This electronic display 31 is placed under the dial portion 20.

To allow to have an electronic display 31 which is visible through the dial module 20 only when it is turned on, it is necessary that the dial module 20 is a semi-transparent element. For this purpose, the dial module 20 then comprises a dial 21 in a translucent or semi-transparent material. This translucent or semi-transparent material may be mother-of-pearl, amber, meteorites, horn, bone, leather, skin (such as snakeskin or crocodile skin), coral, cartilage, semi-transparent minerals (silica, calcite), semi-transparent or tinted glasses, ceramics (oxides, carbides, nitrides, borides) or wood. Indeed, these materials are translucent or semi-transparent when they are in thin plate. In the rest of the description, mother of pearl will be used.

Advantageously according to the invention, the dial module 20 further comprises a semi-reflective element 22. This semi-reflective element 22 is used to have a white mother-of-pearl dial 21 and an electronic display 31 camouflaged when the latter is switched off. and, when the electronic display 31 is on, have the information of the latter which are well visible and well detailed.

For this purpose, the semi-reflecting element 22 is combined with a dial 21 having a given thickness. Indeed, the thickness of the nacre is a parameter that adjusts the diffusion properties to make the nacre clearer. A compromise must be found because if the nacre is too light, the electronic display 31 off can be visible and the mother of pearl appears dark. On the contrary, if the mother-of-pearl is too thick, it appears clearer, but the details of the information of the electronic display 31 will be distorted by the diffusion.

In the case of the present invention, the dial 21 mother of pearl will have a thickness between 0.01 and 0.4 mm with preferred values between 0.1 mm and 0.15 mm. This range of thickness of the mother of pearl makes it possible to have a translucent dial 21 which transmits the light while diffusing it. The total thickness of the dial module 20 is, for its part, between 0.3 and 0.5 mm.

Having such a combination of a mother-of-pearl dial 21 with a semi-reflecting element 22 makes it possible to reflect part of the light and to transmit another proportion of the light without deflection of the light rays by diffusion. Consequently, when the electronic display 31 is off, it is possible to make the mother-of-pearl whiter because the semi-reflective element 22 placed behind the mother-of-pearl dial 21 contributes to the fact that the mother-of-pearl dial 21 reflects more light.

In addition, the total diffusion of the dial module 20 is the diffusion of the dial 21 in mother-of-pearl. However, as the diffusion varies proportionally with the thickness, a mother-of-pearl dial 21 of slight thickness results in a weak diffusion which makes it possible to keep the fineness of the details of the electronic display 31 when the latter is lit. So we combine the advantage in terms of diffusion of a fine mother-of-pearl with the advantage in terms of whiteness of a thick mother-of-pearl.

In a first embodiment, the semi-reflecting element 22 is a semi-reflecting mirror. Such a mirror is made of a metal layer. This metal layer may be made of chromium or silver or aluminum or any other metal or alloy allowing the realization of such a mirror. This metal layer has a thickness of between 1 and 50 nm.

This metal layer can be deposited directly on the mother-of-pearl dial 21 at its surface which is not visible to the user or else via a substrate. For this, a transparent substrate of plastic or other is covered by this layer of metal to be then glued to the dial 21 mother of pearl. The presence of this substrate makes it possible to have an additional layer which will stiffen the dial module 20 and allow it to have greater mechanical rigidity. The dial module 20 will therefore be easier to handle.

A second embodiment is that the semi-reflective element 22 comprises a dielectric mirror. Such a dielectric mirror is composed of a plurality of layers of dielectric materials deposited successively. Manufacturing techniques for dielectric mirrors are based for example on thin film deposition methods. Common techniques are molecular beam epitaxy, ion beam deposition, vapor deposition, physical vapor deposition, and sputtering. These layers of dielectric materials have refractive indices and different thicknesses. As a result, by a phenomenon of constructive interferences, the reflection rate of the light can be considerably increased. The simplest dielectric mirrors 22 are generally colored so that they can be used to color the mother-of-pearl and thus bring a plus in terms of aesthetics. It is possible, however, to obtain neutral-colored dielectric mirrors by combining more complex dielectric material layers to reflect all wavelengths of the visible with the same intensity. In this way, the mother-of-pearl dial 21 retains its original color but seems brighter for the user.

The use of such a dielectric mirror offers a better performance compared to a mirror in the form of layer (s) metal (s) because it absorbs a portion of the light.

In a variant of this second embodiment, the dielectric mirror of the semi-reflective element 22 is produced using birefringent dielectric layers. This use of birefringent dielectric layers causes the appearance of a phenomenon of polarized constructive interferences which offers the advantage of having a more neutral color making the nacre whiter. Such a mirror consisting of birefringent dielectric layers is called reflective polarizer and allows to transmit a polarization while it reflects another.

These reflective polarizers or dielectric mirrors may be in the form of a film, that is to say a thin layer of material such as a sheet. The fact of being in the form of a film makes it possible, when these reflective polarizers or dielectric mirrors are associated with the mother-of-pearl dial, to have greater mechanical rigidity. The dial part 20 will therefore be easier to handle. This film can be flexible or rigid and be made of plastic or a material such as glass or any other usable material.

It is also possible that these reflective polarizers or dielectric mirrors are directly made on the dial 21 at its surface not visible to the user, a rigid or flexible film being glued on top to increase the rigidity of the dial 21 .

This variant is clever in that such reflective polarizers are generally used in electronic displays for energy recycling or to be used as polarizing mirror reflective displays. The use of such reflective polarizers to increase the whiteness of a mother-of-pearl is thus not provided.

Moreover, this variant has the advantage of being commercially available in the form of plastic film. It becomes possible to laminate the film on mother-of-pearl thus avoiding the use of complex and expensive thin film deposition processes.

Claims (14)

In FIG. 2, the semi-reflecting element 22 is shown in the form of a film or substrate carrying either a semi-reflecting mirror or a dielectric mirror, the version of the semi-reflecting element 22 directly made on the dial 21 does not is not represented. In a variant of the first and second embodiments, the display assembly further comprises an opaque film 40 placed between the electronic display 31 and the dial module 20 comprising the dial 21 mother of pearl and the element 22. In fact, behind the dial 21 it is preferable to have a movement whose color is uniform, otherwise there will be disparities in the tones of the mother-of-pearl dial. The film 40 thus serves to hide screws and other reflective pieces that are in the movement. This prevents them from being visible to the user. This opaque film 40 has an opening at the location opposite the electronic display 31 so that the information of the electronic display 31 can be visible to the user. The black color is chosen to highlight the mother of pearl and get a very uniform background. It will be understood that various modifications and / or improvements and / or combinations obvious to those skilled in the art can be made to the various embodiments of the invention described above without departing from the scope of the invention defined by the appended claims. claims A display assembly (10) comprising a display module (30) having an electronic display and a light source for displaying at least one information and a dial module (20) for displaying said information of the display only when it is activated, characterized in that the dial module (20) comprises a dial (21) made of a translucent or semi-transparent material under which is disposed a semi-reflecting element (22). 2. Display assembly according to claim 1, characterized in that the semi-reflecting element (22) comprises a metal layer directly deposited on said dial (21). 3. Display assembly according to claim 1, characterized in that the semi-reflecting element (22) comprises a metal layer deposited on a flexible film. 4. Display assembly according to claim 1, characterized in that the semi-reflecting element (22) comprises a dielectric mirror in the form of a film. 5. Display assembly according to claim 1, characterized in that the semi-reflecting element (22) comprises a dielectric mirror directly made on said dial (21), in the form of a film glued on top to stiffen said dial. Display assembly according to claim 4 or 5, characterized in that said dielectric mirror is composed of a plurality of layers of stacked dielectric materials having refractive indices and different thicknesses. 7. Display assembly according to claim 4 or 5, characterized in that said dielectric mirror is composed of a plurality of layers of birefringent dielectric materials. 8. Display assembly according to one of claims 4 to 7, characterized in that the film is a flexible film. 9. Display assembly according to one of claims 4 to 7, characterized in that the film is a rigid film. 10. Display assembly according to one of the preceding claims, characterized in that the thickness of the dial module (20) is between 0.3 and 0.5 mm. 11. Display assembly according to one of claims 1 to 10, characterized in that the thickness of the dial (21) is between 0.01 and 0.4 mm 12. Display assembly according to one of the preceding claims, characterized in that it further comprises an opaque film (40) located between the display module (30) and the dial module (20), the opaque film. having an opening at the location opposite the electronic display (31). 13. Display assembly according to one of the preceding claims, characterized in that the dial (21) is made of a material included in the list comprising: mother-of-pearl, amber, meteorites, horn, bone leather, skin, coral, cartilage, semi-transparent minerals, semi-transparent or tinted glasses, ceramics or wood. 14. Timepiece characterized in that it comprises a display assembly (10) according to one of claims 1 to 13.