WO2012110729A1

WO2012110729A1 - Set of individual elements intended for forming a mosaic-like structure, and mosaic-like structure and method for producing same

Info

Publication number: WO2012110729A1
Application number: PCT/FR2012/050264
Authority: WO
Inventors: Serge Wrobleski
Original assignee: Serge Wrobleski
Priority date: 2011-02-17
Filing date: 2012-02-07
Publication date: 2012-08-23
Also published as: FR2971729B1; EP2675630A1; FR2971729A1; EP2675630B1

Abstract

The invention relates to a set of individual elements (1) intended for forming, once assembled together, a mosaic-like structure comprising, on one surface, a decoration reproducing an image, the decoration being defined by decoration portions each reproducing a portion of the image, each individual element (1) having a decoration portion on one surface, characterised in that each decoration portion includes one or more formations (2) each corresponding to the image portion or to a sub-portion of the image portion reproduced by said decoration portion, respectively, the or each formation (2) creating an area, the luminance of which is defined in accordance with the shade of grey of the image portion or image sub-portion associated with the formation, the luminance of the area increasing or decreasing with the shade of grey.

Description

ASSEMBLY OF INDIVIDUAL ELEMENTS FOR FORMING A MOSAIC TYPE STRUCTURE, MOSAIC TYPE STRUCTURE AND METHOD OF MAKING SAME

The present invention relates to the field of mosaic type structures, and relates more particularly to a set of individual elements intended to form, once assembled to each other, a mosaic type structure, on a mosaic type structure formed by a such set of individual elements, on a method of making such a mosaic type structure, on a computer program product for the implementation of this method and on a decoration installation incorporating the mosaic type structure.

In the present application, mosaic refers to any juxtaposition of pieces or elements, identical or different, so as to form an integral structure having an outer surface bearing a decoration reproducing at least one given image when a person observing the outer surface is in a given position.

The term "mosaic" as used in the present application thus covers both mosaics in the traditional sense, in which the joints between the tesserae are visible and participate in the attractive visual appearance of the structure, that the structures in which boundaries between different pieces or elements are not visible to the naked eye.

A mosaic type structure is generally in the form of a panel of greater or lesser dimensions and can be fixed to a wall, the floor or on any object, such as clothes, trinkets, etc., the dimensions of the structure being of course adapted to the support on which it must be fixed. Of course, the outer surface of the mosaic-like structure, which carries the decor, may not be flat.

Decorative art has become important today and many techniques have been proposed to provide decorative surfaces with a pleasing appearance to the eye.

One of these techniques is to reproduce an image with a decoration consisting of grooves carved in a surface of a generally white panel. These furrows, generally all hollowed out in the same direction of the panel and therefore parallel to each other, create dark areas of shadow, in contrast with the white color of the unetched surface parts. The image is thus reproduced only in black and white, and its perception by the observer will vary according to the position of the observer with respect to the panel and the orientation of the ambient light.

In order to define the width of the grooves, which determines the luminance of the created shadow zone, and thereby the intensity of the black perceived by the observer, a grayscale color image conversion process is first carried out. on the image to be reproduced. Such processing includes, for example, the steps of decomposing the pixel start image, determining the three RGB components (red, green, blue) of each pixel, and applying a grayscale conversion formula. for each pixel, for example that proposed by the International Commission on Illumination in its recommendation 709 or recommendation 601. It should be noted that the image may also be previously processed to obtain a relief effect, for example by accentuating the gray level differences of the different pixels, so that the observer perceives a three-dimensional image.

Once the width of the grooves has been determined, which generally varies along them, a die is machined using a machining center, so that it forms the counterprint. of the panel that one wishes to obtain. The panels are then manufactured by molding using the matrix thus obtained.

This technique has the advantage of allowing to obtain a panel with a decoration reproducing an image pleasing to the eye and may appear atypical insofar as it appears only in a given position of the observer.

However, this technique has the disadvantage of being expensive to implement, mainly because of the machining operation of the matrix, which can be tedious. Indeed, to obtain an image of satisfactory accuracy, it is necessary to provide a number of grooves that can be important and increasing the cost and duration of the machining operation.

This is further amplified when this technique is implemented on large panels, and this because of the fact that, for the observer to have a sufficiently accurate perception of the image, it is necessary that it is located several meters away from them.

Therefore, due to the need of manufacturers to offer panels incorporating this technique at reasonable costs, the range of images manufacturers has been greatly limited, in order to amortize the investment represented by the manufacture of a matrix, especially if the need for a machining center is taken into account.

In seeking a solution to these problems, the applicant has realized that it is possible to obtain such panels using standard individual elements each comprising a part of decor comprising one or more grooves of which the luminances of the zones are known. of shadow that they create according to the position of the observer. The applicant has also realized that it is possible not to limit the use of the gray level in connection with furrows, but to widen it to the definition of zones whose luminances are defined according to the level of gray. Thus, each individual element carries a part of the decoration reproducing a part of the overall image thanks to the luminance difference, and thus to the contrast, between different zones of the individual element. The use of individual elements that are assembled can also make it possible to obtain a visual effect similar to that produced by a mosaic and which is pleasing to the eye.

The present invention therefore relates to a set of individual elements intended to form, once assembled to each other, a mosaic type structure carrying, on one side, a decor reproducing at least one image, the decor being defined by parts of decoration each reproducing a corresponding part of said at least one image, each individual element carrying such part of decoration on its face intended to be part of the face of the structure carrying the decoration, characterized by the fact that each part of the decoration comprises one or more formations corresponding respectively to the image part or to a sub-part of the image part reproduced by the decor part, the or each formation creating an area having a luminance defined according to the gray level of the image part or image subpart associated with the formation, the luminance of the increasing or decreasing area with the gray level.

The decor part is formed by the face and the formation or formations it carries, the face possibly being involved in the reproduction of the image portion or the image subpart associated with the individual element.

The correspondence between the gray level and the luminance of the zone created by a formation can be established empirically or after computer simulation.

It can be envisaged that each image portion corresponds to a pixel of the starting image, in which case it is of a color and each individual element comprises a formation creating an area whose luminance corresponds to the gray level of said color.

It goes without saying that in this case, the dimensions of the individual elements must be sufficiently small, for example of the order of a centimeter, to reproduce an image with a sufficient resolution to be pleasing to the eye.

It is also possible to imagine that each image portion can be formed of a plurality of image sub-parts, i.e., pixels, each of a color. In other words, the image portion associated with the individual element comprises a plurality of pixels. Each image subpart, or pixel, is converted to a level of gray, and for each image sub-part, a formation is performed on the individual element to create an area whose luminance corresponds to the gray level of the image sub-part and whose position on the individual element corresponds to the position of the image subpart, or pixel, in the image part.

Thus, the individual element corresponding to such an image portion has a plurality of formations each corresponding to an image sub-part, or pixel, so that the individual element carries a part of the decoration reproducing a part of the image. more complex picture.

It goes without saying that if the gray level of the image part or the image sub-part corresponds to the white, the corresponding individual element carries no formation and the part of decoration is formed by a face of the image. individual element.

Advantageously, such an image portion corresponds to a particular graphic element, for example a repeating pattern, so that the corresponding individual element carries a decoration reproducing this graphic element.

It is therefore found that the present invention also makes it possible to compose an overall image from a plurality of image parts, which each correspond to a graphic element mentioned above, so that the buyer can compose himself, to from different image parts independent of each other, the image he wants to take as decoration.

Thus, it is now possible to propose a bank of graphical elements to the user, who can compose his mosaic, and it is sufficient to assemble the individual elements associated with each graphic element so as to form the mosaic. It should be noted that this makes it possible to solve the problem of limiting the range of images proposed to buyers when trainings are train paths as described above, since it is no longer necessary to amortize the investment associated with the manufacture of dies. On the contrary, since a single matrix, allowing the production of a graphic element, can be used for several images, the range of images proposed can be significantly enlarged while reducing their price.

In addition, in such a case, the dimensions of the individual elements may be larger, for example of the order of tens of centimeters, so that the assembly operation of the different individual elements composing the desired mosaic type structure is simplified.

According to one embodiment, the formations consist of lumps of a photoluminescent, phosphorescent or fluorescent material, and in particular of a mixture of photoluminescent powder, phosphorescent or fluorescent, and of resin, applied to the individual elements, the photoluminescent material. , phosphorescent or fluorescent, where appropriate the photoluminescent, phosphorescent or fluorescent powder, being concentrated according to the gray level of the image part or the image sub-part associated with the cluster, the photoluminescent, phosphorescent power or fluorescent, increasing as the gray level increases.

Preferably, the photoluminescent, phosphorescent or fluorescent powder used is a powder whose photoluminescent, phosphorescent or fluorescent power is of long duration and is recharged by light. These powders are now well known and widely available commercially, for example from the company Idem Conseil. For example, polyester resin, epoxy resin or polyurethane resin may be used as the resin. The concentration of the photoluminescent, phosphorescent or fluorescent material, in the direction of photoluminescence, phosphorescence or fluorescence intensity, produced, may be modified by dilution or by the application of a greater or lesser amount of material. The structure formed by such individual elements can in this way reproduce an image in the dark, especially at night, and recharge the day.

According to another embodiment, the formations are constituted by reliefs and / or recesses, each creating a shadow zone whose luminance, which is defined, in a given position of a person observing the mosaic-like structure, depending on the gray level of the image portion or the image subpart, decreases as the gray level of the image portion or image subpart associated with them increases.

Whether the formations are lumps of photoluminescent material, phosphorescent or fluorescent, or reliefs and / or hollows, it is possible to separate the image they reproduce from a background image reproduced by the colors of the elements. individual.

In other words, it is possible to combine the present invention with the technique of traditional mosaics.

Traditional mosaics consist of a juxtaposition of pieces of ceramic, marble, enamel or stone, called tesserae, which are glued either on their final support, which can be a wall, a ground, an object, etc., or on a fiberglass net that will then be stuck on the final support. In the traditional technique, the tesserae are obtained directly by cutting a basic material, sometimes followed by cutting by hand. The most common dimensions for tesserae are 1 to 3 centimeters for a little less than 1 centimeter thick.

The materials used to make the tesserae are usually naturally colored in the mass, but it is possible to apply a layer of paint on the tesserae, the principle being that each tessera is of a single color.

Thus, the assembly of the tesserae, generally using putty, hydraulic glue or plaster, makes it possible to form a background decoration that can optionally reproduce a given image, the reproduction of the latter being then defined by the different colors of the tesserae.

It emerges that the combination of the traditional mosaic technique with the present invention, that is to say, to color the individual elements according to the invention to reproduce an image once they are assembled to each other, offer multiple opportunities. In this respect, the faces of the individual elements carrying the decor parts can be colored. It is possible to apply a color on the face of the individual elements by an inkjet printing process, or to dye the individual elements in the mass.

As indicated above, it is conceivable to dissociate the image reproduced by the colors of the individual elements of the one (s) formed by the formations, and thus obtain a superposition of images, which is not feasible in traditional mosaic. Alternatively, the formations may be defined such that the luminance of the zones they create corresponds to the gray level of the color of the individual element. In this case, the formations have the effect of reinforcing and improving the visual rendering of the image reproduced by the decor of the structure.

It is also possible to create a mosaic type structure intended to be arranged on the facade of a building, for example a house, and which reproduces an image that has been defined so that in summer, the formations individual elements produce shading areas that can lower the temperature of the facade, facilitating convection movements, and in winter, these same areas allow heating of the facade. The formations of the individual elements according to the invention are thus used to achieve microombrage or mini-shading of the facade.

In other words, the starting image is defined, in particular according to the position of the sun and its movement throughout the year, so that once converted into gray levels, the positions of the Dark areas correspond to real shading areas that prevent overheating in the summer and keep the building warm in the winter.

The determination of such a starting image is done after a very precise calculation of the exposure of the house.

When the formations are troughs, a material having an optical modulation effect, namely a shrinking, magnifying or reflecting effect, such as a silica glass or a material containing quartz crystals, may be disposed in hollow so as to modulate the optical effect produced by the shadows. Such a material makes it possible to accentuate or lessen the effect produced by the hollows. This is particularly advantageous when using individual elements of very small dimensions, in which case the visual effect of the decorating parts alone may not be sufficiently perceptible to the eye.

In the case where the individual elements are colored to reproduce an image in the background, in the manner of a mosaic, and the formations are defined so that the luminances of the zones that they create correspond to the color of the image. individual element, the arrangement of such a material makes it possible to further reinforce the effect of the formations, by the diffusion of the outlines of the hollows: the user will no longer perceive the hollows in themselves, but only the shaded areas they create.

According to a particular optional feature, the recesses are straight and parallel grooves whose dimensions increase when the gray level of the image portion or image subpart associated with it increases. In other words, it implements the etching technique described above in connection with the prior art.

The grooves may have any of a variety of cross-sectional profiles. The grooves may for example have a rectangular transverse profile, in which case the width and / or the depth of the grooves increase when said gray level increases. The grooves may also have a triangular transverse profile, defined by two inclined surfaces joining at the bottom of the groove at an angle, in which case the depth and / or inclination of the surfaces and / or the angle increase when said gray level increases. Said angle can be in a range from 1 ° to 179 °, preferably in a range from 30 ° to 120 °.

According to a particular optional feature, the recesses each consist of a cone cut into the individual element, the half-angle of the cone being in particular in a range from 1 ° to 89 °, and preferably in a range from ° at 60 °.

According to a particular optional feature, a fluorescent material, phosphorescent or photoluminescent, and in particular a mixture of fluorescent powder, phosphorescent or photoluminescent and resin, is disposed in the recesses so as to reproduce the image in the dark. The same materials and the same resin as those mentioned above can be used.

It should be noted here that when the formations carried by the individual elements are reliefs or hollows, they create an area whose luminance corresponds to a given gray level according to the lighting given to the individual elements, and therefore according to the given position. of the observer with respect to the mosaic-like structure in the case of constant and immobile lighting.

In other words, in the latter case, the perception of the image that the observer depends on its position, so that it is possible to predict that each individual element comprises a first series of formations reproducing a first image portion in a first position of the observer, but also a second series of formations reproducing a second image portion, identical or different from the first image portion, in a second position of the observer. The number of training series is of course not limited to two, but to the maximum number of training courses be performed on the individual element while allowing them to fulfill their function of creating a given luminance area. This therefore depends on the dimensions of the individual elements.

It is also possible to provide that the mosaic-like structure comprises a first set of individual elements that bear formations that correspond to a first image that can be seen when a first given position relative to the mosaic-like structure, and a second set of individual elements that bear formations that correspond to a second image when in a second position, different from the first position.

Consequently, the set of individual elements according to the present invention makes it possible to reproduce a succession of images, different or identical, when the observer moves with respect to the mosaic-like structure when the lighting is constant and immobile.

Such a succession of images can also be obtained when the observer is stationary, by positioning a lighting source so that it variably illuminates the mosaic-like structure. Such a variation can be obtained either by displacement of the lighting source with respect to the structure, or by modulation of the intensity of the lighting according to certain regions of the structure, or a combination of the two.

Of course, such a lighting source can be controlled so that the structure produces a succession of images depending on the displacement of the observer relative to the structure. Thus, for example, the mosaic type structure can extend over the floor or a wall of a corridor, a light source being arranged opposite along the corridor and illuminating the structure according to a predefined speed of movement of a person crossing the corridor. It is also possible to provide position sensors communicating with a computer controlling the lighting source, so that the latter can illuminate the structure according to the actual speed of the person crossing the corridor.

It is also possible to combine a succession of images, obtained as described above, with the permitted image overlay if the present invention is combined with the traditional mosaic technique. Consequently, the present invention makes it possible to obtain a mosaic-like structure reproducing a background from which a succession of images is detached as a function of the displacement of the observer or of a lighting source, or both.

Preferably, the individual elements have the same cross-sectional shape, in particular hexagonal or square. This allows easy and fast assembly.

The distance between two opposite sides of each individual element may be 4 mm when the individual elements each correspond to a pixel or part of an image.

If the individual element represents an image part composed of several image subparts, or pixels, so that the decoration part of the individual element reproduces a graphic element as described above, the individual element can be in the form of a plate of 30 cm ² , of variable shapes, preferably nestable. Individual elements may comprise means capable of emitting light towards the outside from the outer face, carrying the decorative part, of said individual element, such means being notably constituted by an optical fiber connected to a light source. .

The individual elements may be made of any material, preferably of a moldable material. In particular, they can be made of cement mortar, ceramic, stone, magnesia, terra cotta, polyurethane resin, epoxy resin, etc.

The individual elements may also be made of a reflective material, such as glass. This makes it possible to obtain particularly pleasant visual effects.

The present invention also relates to a mosaic-like structure carrying a decor reproducing at least one image, characterized in that it is composed of the set of individual elements as defined above, assembled to each other .

The present invention also relates to a method for producing a mosaic type structure as defined above, from a set of individual elements as defined above, implemented by computer, characterized by the fact that it comprises the steps of:

executing an algorithm on a starting image, said algorithm decomposing, according to the individual elements of the set of individual elements, the starting image into image parts so that the gray level or levels in each part of the image corresponds to the part of the decoration of at least one individual element, the image parts whose level or levels of gray do not match the decor portion of at least one individual element being decomposed into smaller image portions in an iterative manner until the gray level or levels of each image portion correspond to at least one individual element of the set; and

constructing the mosaic type structure from the individual elements which carry a part of decoration having one or more formations creating an area having a luminance corresponding to the gray levels of the image parts, so as to obtain a mosaic-type structure a decoration reproducing the original image.

For example, we can predefine the parameters of the individual elements that are available to build the mosaic, such as their geometric shapes and dimensions, the shapes and dimensions of the formation or formations they carry, the size of the joints between the individual elements, etc., and put them in input of the algorithm.

It is also possible to allow the user to modify the grayscale conversion formula used by the algorithm to convert the initial image to grayscale.

It should be emphasized here that, insofar as the individual elements reproduce an image, the present invention is not limited to a particular technique of graphic representation, but on the contrary makes it possible to reproduce paintings, frescoes, drawings, etc. because they can be put in the form of a digital image. In particular, one can apply the technique of stereoscopy and use an image stereoscopic for the decoration to produce the illusion of a relief image.

The method according to the invention may furthermore comprise, after the execution of the algorithm and before the step of constructing the mosaic type structure, a computer simulation step of the final mosaic type structure and, where appropriate, optionally, a step of re-executing the algorithm after modification by the user of the set of individual elements available.

Thus, if the rendering obtained after indicating, for example, a first size of individual elements available and a first series of dimensions of the formations they carry, the resolution of the image reproduced by the decoration can be increased. of the mosaic type structure by indicating smaller sizes of individual elements and for example a larger number of formation dimensions.

The simulation advantageously takes into account the position and / or the displacement of the observer and / or the lighting source (s) and allows the interactive manipulation of the position and / or the displacement of the observer and / or the or lighting sources.

When used to form the individual elements of the light-reflecting materials, even slightly, this simulation also takes into account this reflection.

When a material having an optical modulation effect is placed in the recesses of individual elements, the simulation step also takes this matter into account. As indicated above, it is also possible to provide a step of processing the initial image, for example to accentuate the contrasts.

The present invention also relates to a computer program product storing an executable code for executing the algorithm of the method as defined above and the implementation of the simulation step of the mosaic type structure final and step of re-execution of the algorithm of the method as defined above.

The present invention also relates to a decoration installation, characterized in that it comprises a mosaic-like structure as defined above and a lighting source arranged to illuminate the mosaic-like structure, in particular in a variable manner, by moving the light source, either by modulating the illumination intensity of the structure, or a combination of both.

To better illustrate the object of the present invention, will be described below an embodiment with reference to the accompanying drawings.

On these drawings:

- Figures 1, 2 and 3 are views respectively in perspective, front and longitudinal section next

A-A, a hexagonal cross-sectional element of a set of individual elements according to the present invention, the decorative part associated with this individual element having a dark zone created by a conical recess;

FIG. 4 is an overall perspective view of a mosaic type structure produced by the assembly a plurality of hexagonal individual elements as shown in Figures 1 to 3 and having cones of different depths; - Figures 5 and 6 are views respectively in perspective and in longitudinal section of a first variant of the individual element according to the present invention, of square cross section; Figure 7 is an overall perspective view of a mosaic-like structure made by assembling a plurality of individual square elements as shown in Figures 5 and 6 and having cones of different depths; Figure 8 is a perspective view of a second variant of the individual element according to the present invention, the decor part associated with this individual element having a dark zone created by a groove;

Figure 9 is a perspective view of a mosaic type structure made by assembling a plurality of individual elements as shown in Figure 8 and having furrows of different widths;

Fig. 10 is a photograph of a mosaic-like structure constructed from individual elements according to the present invention, of hexagonal cross-section and conical depressions, the structure representing part of a woman's face; Figure 11 is an enlarged view of Figure 10 showing more precisely the corner of the eye;

Figure 12 is a photograph of a mosaic-like structure showing the same part of a woman's face as Figure 10, the structure being constructed from individual elements of square and grooved cross-section; and Figure 13 is an enlarged view of Figure 12 showing more precisely the corner of the eye.

Referring to FIGS. 1 to 3, it can be seen that there is shown an individual element 1 according to a particular embodiment of the invention, this individual element 1 being elongated and having a cross-sectional shape hexagonal. Individual elements 1 having such a cross-sectional shape have a much better compressive strength.

This individual element 1 comprises a decorative part formed by a conical recess 2 made in the center of one of its end faces, namely its outer face 3 intended to constitute a part of the surface of the mosaic type structure. once the different individual elements 1 assembled to each other. The decor part is also formed by the area of the face 3 around the hollow 2.

The conical recess 2 represented being a rectangle cone, its geometry can be defined by its depth Hc, which is equal to half of its diameter De, taken in the plane of the outer face 3, the apex angle a being 90 °. The hollow 2 traps the light and therefore produces a dark zone in the center of the individual element 1, the intensity of the dark zone being determined by the dimensions of the recess 2.

Thus, the depth of the cone, that is to say the level of penetration of the hollow 2 in the individual element 1, determines the intensity of darkness in the center of the individual element 1. This depth of cone Hc may for example vary from 0 mm to ^{1/10 th} of the thickness of the individual element 1. For example, for an individual element 1 whose distance between opposite sides is 4 mm and whose thickness is 15 mm. mm, the depth of the cone may vary from 0 mm to 3 mm.

We can also vary the intensity of the darkness formed by the cone by varying, not its depth, but its half angle, the cone is no longer a rectangle cone. In this case, the larger the cone half-angle, the greater the intensity of the dark zone created by the cone.

As indicated above, the intensity of the dark area is defined according to the gray level of the image portion to be reproduced by the decorative part carried by the individual element 1.

The choice of the dimensions of the recesses 2 can be made empirically, depending on the resolution that is desired, as well as the thickness of the individual elements 1.

Preferably, one makes this choice after having simulated on a computer the rendering of the final structure.

It is possible to use a variety of grayscale scales, more or less precise and complex, the important thing being that each level of gray associated with a corresponding cone depth, or if necessary a half angle of the cone.

It appears, however, that the use of a 16-level gray scale is a satisfactory choice, in that it offers a satisfactory accuracy without generating too many cones of different dimensions.

The following Table 1 is an example of a look-up table for associating with each gray level of a 16-level gray scale, a cone producing an area of darkness having an intensity corresponding to this gray level, for a gray scale. individual element 1 having a thickness of 1 cm and a distance between opposite sides of 4 mm. This table also contains values for a rectangular cone with an angle of 90 ° and a nonrectangle cone whose half-angle is 30 ° (a = 60 °).

Table 1

The individual element 1 can be made of cement paste or vibropressed concrete mortar or molded in thermoformed molds with an imprint corresponding to the desired individual element shape. The individual element 1 may also be colored in the mass by oxides, or simply colored by surface application of a paint layer.

It is advantageous to make all the individual elements 1 in advance so as to have at disposal a set of individual elements 1 corresponding to all the gray levels of the scale used for the conversion of the image into grayscale. . It is thus possible to produce with such a set of individual elements 1 mosaic-type structures whose decor reproduces any given image.

Referring now to Figure 4, it can be seen that there is shown a mosaic type structure composed of a set of individual elements 1 having recesses 2 of different dimensions. The hollows 2 of larger diameters are here placed in the center of the mosaic type structure, the hollows 2 of smaller diameters being placed in the edge regions.

It is emphasized here that this Figure is given solely to show the arrangement of the individual elements 1, the shadow areas created by the recesses 2 are not shown for the sake of clarity of the drawing.

Such a mosaic type structure can be performed in the following manner, using an algorithm executed on a computer.

Firstly, it decomposes a starting image which it is desired that it be reproduced by the decoration of the mosaic, in a plurality of image parts whose dimensions correspond to those of the individual elements 1. Preferably, the The starting image is pixelated, that is, the image portions mentioned above are the size of the pixels of the original image. Since pixelation techniques are well known, they do not will not be described in more detail. In the case of pixelation, the dimensions of the individual elements 1 must correspond to the size of the pixels defining the image.

The image thus pixelated is then modeled in grayscale, according to the scale chosen. Grayscale modeling techniques are also well known and will not be described in more detail.

Once each pixel has been associated with a gray level, it is easy to find, using a correspondence table such as the one indicated above, the individual element 1 whose hollow 2 produces an area of darkness whose intensity corresponds to the defined gray level.

The positions of the different pixels being known, it is easy to arrange the different individual elements 1 relative to each other, in the same way as for conventional mosaics, to obtain a mosaic whose decor reproduces the image that has been pixelated.

This step of arranging the individual elements 1, including their recovery from a storage location, for example, can be executed by one or more robots or robotic arms, well known in the art, which have been programmed for they place each individual element 1 at its position on the support of the mosaic type structure.

Such a mosaic structure however differs from conventional mosaics in that it has a much better visual effect due to the presence of the troughs 2 trapping the light and providing a feeling of depth of the image. It should be noted that it is possible to represent an image only by the contrast between the dark areas and white areas, the individual elements 1 then not being colored. This is directly inspired by the principle of defragmenting an image.

In the same way, it should be noted that the observer's perception of the dark zones, and therefore the image reproduced by the decoration, will vary according to the position of the observer with respect to the mosaic-like structure. . Thus, when it moves in front of the mosaic type structure according to the invention, the observer will perceive a dynamic movement of the decor, particularly pleasing to the eye.

It is also conceivable to have the lighting sources, fixed or mobile, in front of the mosaic type structure according to the invention in order to modify the dark areas on the different individual elements 1 and thus produce different images for an observer remaining at a given position.

If the individual elements 1 are colored to reproduce a first image in the conventional manner of a traditional mosaic, it is possible to define the hollows 2 from another reference image so that the observer can perceive this image. reference, produced by the hollows 2, detaching from a background image produced by the colors of the individual elements 1.

If we associate this with the possibility of producing a moving decoration as indicated above, a mosaic-like structure according to the invention makes it possible to reproduce a background image from which an image in dynamic motion is detached when the observer moves relative to the mosaic-like structure or when the lighting of the mosaic-type structure is varied.

It is furthermore possible to define the hollows 2 of a first set of individual elements 1 from a first reference image and the hollows 2 of a second set of individual elements 1 from a second image. reference, so as to obtain, after assembly of the individual elements 1 of the first and second sets, a mosaic-like structure carrying a decoration reproducing in the background a first image, produced by the colors of the individual elements 1, from which stand out first and second moving images.

The invention is of course not limited to a defined number of images, this number being limited only by the overall dimensions of the mosaic type structure and the number of individual elements 1 the component.

The computer implementation of these steps of image decomposition, determination of gray levels and determination of the corresponding individual elements 1 is particularly advantageous in that it also makes it possible to simulate the visual rendering of the structure of the image. final mosaic type, so that superimpositions or successions of images can be observed, preferably taking into account the position of the observer and / or light sources, before the final assembly step.

The invention is furthermore not limited to the shape of the cross-section of the individual elements 1.

Thus, there is shown in Figures 5 and 6 an individual element 4 according to a first variant, whose cross-sectional shape is square and which is relatively elongated. Similarly to the individual element 1, this square element 4 has, in the center of an end face 5, a hollow 6 in the form of a cone creating a shadow zone.

It is therefore possible to obtain a mosaic-like structure according to the invention, as shown in FIG. 7.

Hexagonal and square shapes are two examples of the cross-sectional shape that can be used for the individual elements of the invention. Any other form can thus be used provided that it allows the elements to be assembled together. In particular, it is possible to provide, in the same set of individual elements, individual elements of different shapes in cross section.

Nevertheless, the use of the hexagonal or square shape, or generally rectangular, allows an extremely fast assembly and can be automated to save time and lower costs.

Moreover, it is irrelevant whether the individual elements are elongated or not.

Other forms of decorative parts can also be envisaged.

Thus, it is possible to use individual elements 7 according to a second variant of the invention, which are rather elongated and of square cross-section, as can be seen in FIG. 8.

The individual element 7 carries, hollowed on an end face 8, a groove 9 extending rectilinearly from one edge of the face 8 to the opposite edge.

The groove 9 has a triangular profile formed by two surfaces 9a, 9b inclined towards each other and joining along a line 9c forming the bottom of the furrow 9.

The groove 9 creates a shadow zone whose luminance is a function of its dimensions, in particular as a function of the depth of the groove 9, the area of the surfaces 9a, 9b and the angle they form at the bottom 9c of the groove 9.

Here again, the various appropriate dimensions and their correspondence with the gray levels can be determined empirically or by computer simulation, as in the case of conical depressions 2, 6.

The individual elements 4, 7 according to the first and second variants can be obtained in the same way as the individual elements 1 and the steps of producing a mosaic-type structure using these individual elements 4, 7 are identical to those described above.

As indicated above, the formations may also consist of reliefs or clusters of phosphorescent material. These reliefs or clusters are associated with a given gray level in the same way as for the hollows.

FIGS. 10 to 13 show photographs showing a mosaic-like structure according to the present invention, which figures show that the present invention makes it possible to construct mosaic-type structures producing an excellent visual effect.

In particular, Figures 10 and 11 show a mosaic-like structure in which the traditional mosaic technique is combined with providing depressions. Thus, the individual elements each carry a hollow, they are colored to reproduce the image of the face and the depressions are formed such that the luminance of the shadow zone produced by each trough corresponds to the gray level associated with the color of the individual element.

Figures 12 and 13 show the same image reproduced by a structure composed of individual elements of square cross section and each having a groove, which produces the black area in the center of each individual element, the individual elements being arranged so that, in the same column of individual elements, the grooves are in the extension of each other.

It is understood that the embodiment which has been described above has been given as an indication and not limitation and that modifications can be made without departing from the scope of the present invention.

Claims

1 - Set of individual elements intended to form, once assembled to each other, a mosaic type structure carrying, on one side, a decoration reproducing at least one image, the decoration being defined by parts of decoration each reproducing a corresponding part of said at least one image, each individual element (1, 4, 7) carrying such a part of decoration on its face intended to be part of the face of the structure carrying the decoration,

characterized by the fact that

each part of the decoration comprises one or more formations (2, 6, 9) corresponding respectively to the image part or to a subpart of the image part reproduced by the decoration part, the or each formation (2 , 6, 9) each creating an area having a luminance defined according to the gray level of the image portion or image subpart associated with the formation, the luminance of the increasing or decreasing area with the level of gray.

2 - Set of individual elements according to claim 1, characterized in that the formations are constituted by reliefs and / or recesses (2, 6, 9), each creating a shadow zone whose luminance, which is defined, in a given position of a person observing the mosaic-like structure, depending on the gray level of the image part or the image sub-part, decreases when the gray level of the part of image or image subpart that is associated with them increases.

3 - set of individual elements according to claim 2, wherein the formations are recesses (2, 6, 9), characterized in that a material having a optical modulation effect, namely a shrinking, magnifying or reflecting effect, such as a silica glass or a material containing quartz crystals, is arranged in the recesses (2, 6, 9) so as to modulate the optical effect produced by the shadow areas.

4 - Set of individual elements according to one of claims 2 and 3, wherein the formations are recesses, characterized in that the recesses are grooves (9) rectilinear and parallel whose dimensions increase when the gray level of the image portion or image subpart associated with it increases.

5 - set of individual elements according to one of claims 2 and 3, wherein the formations are recesses, characterized in that the recesses (2, 6) each consist of a cone dug in the individual element, the half angle of the cone being in particular in a range from 1 ° to 89 °, and preferably in a range from 15 ° to 60 °.

6 - set of individual elements according to one of claims 2 to 5, wherein the formations are recesses (2, 6, 9), characterized in that a fluorescent material, phosphorescent or photoluminescent, and in particular a mixture fluorescent powder, phosphorescent or photoluminescent and resin, is disposed in the recesses (2, 6, 9) so as to reproduce the image in the dark.

7 - set of individual elements according to claim 1, characterized in that the formations consist of clusters of a photoluminescent material, phosphorescent or fluorescent, and in particular a mixture of photoluminescent powder, phosphorescent or fluorescent, and resin, applied to the individual elements, the photoluminescent material, phosphorescent or fluorescent, where appropriate the photoluminescent, phosphorescent or fluorescent powder, being concentrated according to the gray level of the image portion or the image sub-part associated with the cluster, the photoluminescent, phosphorescent or fluorescent, increasing as the gray level increases.

8 - Set of individual elements according to one of claims 1 to 7, characterized in that the faces (3, 5, 8) of the individual elements (1, 4, 7) carrying the decor parts are colored.

9 - Set of individual elements according to one of claims 1 to 8, characterized in that the individual elements (1, 4, 7) have the same shape of cross section, in particular hexagonal or square.

10 - Set of individual elements according to one of claims 1 to 9, characterized in that individual elements comprise a means adapted to emit light to the outside from the outer face, carrying the decor part of said individual element, such means being in particular constituted by an optical fiber connected to a light source.

11 - Mosaic type structure bearing a decoration reproducing at least one image, characterized in that it is composed of the set of individual elements (1, 4, 7) as defined in one of claims 1 to 10, assembled to each other.

12 - Process for producing a mosaic type structure as defined in claim 11, from a set of individual elements (1, 4, 7) as defined in one of claims 1 to 10, implemented by computer, characterized in that it comprises the steps of: executing an algorithm on a starting image, said algorithm decomposing, as a function of the individual elements (1, 4, 7) of the set of individual elements, the starting image into image parts so that the or the gray levels in each image part correspond to the decoration part of at least one individual element (1, 4, 7), the image parts whose gray level (s) do not correspond to the part of the image at least one individual element (1, 4, 7) being decomposed into smaller image portions in an iterative manner until the gray level (s) of each image portion corresponds to at least an individual element (1, 4, 7) of the assembly; and

- constructing the mosaic-like structure from the individual elements (1, 4, 7) carrying a decor part having one or more formations (2, 6, 9) creating an area having luminance corresponding to the gray levels of the parts image, so as to obtain a mosaic-like structure bearing a decoration reproducing the initial image.

13 - Process according to claim 12, characterized in that it further comprises, after the execution of the algorithm and before the step of constructing the mosaic type structure, a computer simulation stage of the structure final mosaic type and, where appropriate, a step of re ^¬ executing the algorithm after modification by the user of the set of individual elements (1, 4, 7) available.

14 - Computer program product storing an executable code for executing the algorithm of the method as defined in claim 12 and the implementation of the step of simulating the final mosaic type structure and the step of re-executing the algorithm of the method as defined in claim 13.

15 - Decoration installation, characterized in that it comprises a mosaic type structure as defined in claim 11 and a lighting source arranged to illuminate the mosaic type structure, in particular in a variable manner or by displacement of the lighting source, either by modulating the lighting intensity of the structure, or a combination of both.