WO2008095909A1

WO2008095909A1 - System for representing images by rear projection

Info

Publication number: WO2008095909A1
Application number: PCT/EP2008/051366
Authority: WO
Inventors: Javier Ortiz Jimenez
Original assignee: Javier Ortiz Jimenez
Priority date: 2007-02-05
Filing date: 2008-02-04
Publication date: 2008-08-14
Also published as: ES2323616A1; ES2323616B1

Abstract

The system for representing images object of the invention comprises a transparent layer (1), a back projection layer (2) back to back with one side of said layer and a projector (3), and it is characterised in that it comprises a micro-perforated poster (6) back to back with said layer by the external side. This arrangement permits, on one side, during hours with low lightning levels, that the greater part of the lightning radiation form a shop window to come from the projector, so that an observer can see the projected images not seeing the image of the micro-perforated poster and, on the other hand, during hours with high lightning levels and the projector being off, e.g. during the day, that the lighting radiation comes from the external light reflected on the poster, so that an observer, instead of seeing the screen, will see the micro-perforated poster.

Description

SYSTEM FOR PRESENTING IMAGES BY REAR PROJECTION

The present invention refers to a system for representing images comprising a back projection screen back to back with a transparent layer that is effective with any lighting level.

BACKGROUND OF THE INVENTION

Back projection systems are well-known for publicity in transparent surfaces of shop windows consisting in a back projection screen back to back with said surface by its inner part, on which images are projected from a projector placed inside the shop, so that the publicity image can be seen from outside.

These back projection systems present the drawback that, during the day, the intensity of the incident light from outside reflected by the external surface of the transparent surface is greater than the intensity of the light from the projector transmitted by the screen, so that the projected images cannot be distinguished suitably, and the zone of the shop window covered by the back projection screen is not usable for publicity during the day. A solution for this drawback is to use projectors with a great lighting power. However, these projectors are expensive, originally and during its operation, and they also present, due to their size and weight, difficulties from a point of view of their integration in a working environment, such as an office.

An alternative is to use projectors with medium provisions and use them only during hours with a low lighting level, so that during the day or with high external lighting levels, the shop window presents a dark zone, not aesthetic and unusable from a publicity point of view .

Another solution to this drawback is to disregard the publicity technique by projecting images and use static publicity adhered to the transparent surface.

This solution lacks the versatility that the projection system offers, and also has the drawback that it is not attractive without light.

Therefore, it is evident the necessity to provide a system for representing images for shop windows avoiding said drawbacks, i.e. that permits to use the surface of the shop window to represent images during the day and also during the night.

DESCRIPTION OF THE INVENTION

With the system for representing images said drawbacks are solved, presenting other advantages that will be described hereinafter. The system for representing images object of the invention comprises a transparent layer, a back projection screen back to back with one side of said layer and a projector, said layer and said screen separating an internal space from an external space, the projector being placed at the internal side, and it is characterised in that it comprises a micro-perforated poster back to back with said layer by the external side.

This arrangement permits, on one hand, that during the hours with low lighting levels, the greater part of the lighting radiation from the shop window comes from the projector, so that an observer can see the projected images not seeing the image of the micro-perforated poster and, on the other hand, during the hours with high lightning levels and with the projector off, e.g. during the day, the lighting radiation comes from the external light reflected on the poster, so that an observer will see the micro- perforated poster, not the screen.

A remarkable result of the combination is that the projection screen will increase the contrast of the image contained in the micro-perforated poster.

Preferably, the optical transmittance of said screen is such that with a low lightning level by the external side, the images projected by said projected can be clearly distinguished.

Advantageously, the screen of said representation system is an adhesive film or is a methacrylate film, so that it permits a quick and comfortable installation on a transparent layer. More preferably, said micro-perforated poster is adhesive, so that it permits its installation in an easy way.

More preferably, the projector of the representation system object of the invention is of a 24/7 kind, i.e. it can be operated continuously and guarantees an intensive use.

Finally, the system can include an adhesive film with interactive technology sensitive to pressures exerted by the external side placed between the back-projection screen and the transparent layer, so that it permits an interactive use for an observer.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of that has been described some drawings are attached in which, diagrammatically and only as a non-limitative example, a practical case of embodiment is shown.

Fig. 1 is a section view of the system, in which the relative arrangement of the elements can be seen.

Fig. 2 is a diagrammatical diagram of the balances of lighting radiation in hours of low lighting intensity.

Fig. 3 is a diagrammatical diagram of the balances of lighting radiation in hours of high lighting intensity.

DESCRIPTION OF PREFERRED EMBODIMENTS

According to a preferred embodiment, as it can be seen in Fig. 1, the system for representing images object of the invention comprises a transparent layer 1, a projection screen 2 back to back with a side of said layer 1 and a projector 3, said layer 1 and said screen 2 separating an internal space 4 from an external space 5, and a micro-perforated poster 6 back to back with said layer 1 by the external side.

The operation of said system can be seen in Fig. 2, when it is used during the night, and in Fig. 3, when it is used during the day. In Figs. 2 and 3, it must be understood that the width of the arrows represents for guidance relative intensities of the lighting radiation.

Therefore, as it can be seen from Fig. 2, during hours with a low lightning level, a substantial fraction 7 of the projected lightning intensity 8 by the projector is transmitted by the screen 2, the glass 1 and the poster 6, so that the image can be seen by an observer 9. At the same time, a fraction 11 of the light from the outside 10 is reflected by the poster 6, so that it also reaches the observer 9.

However, in the representation system of the invention the transmittance of the screen 2 and the absorbance of the poster 6 are selected so that the intensity 7 is so much greater than the intensity 11, permitting the observer 9 to differentiate the image from the micro-perforated poster 6 and to observe only the image projected by the projector 3.

Instead of this, as it can be seen in Fig. 3, during hours with a high lightning, e.g. during the day, the projector is off and the fraction of reflected light

11 is so much greater, so that the observer 9 can see the image contained in the micro-perforated poster 6.

Furthermore, during the day, the screen 2 provides a better contrast of the micro-perforated poster 6 preventing the transmission of environmental light from inside 4 the shop.

In a second preferred embodiment, the system can include an adhesive film with interactive technology sensitive to pressures exerted by the external side 5 placed between the back projection screen 2 and the transparent layer 1, so that the observer can select the desired information.

With this device the area of the shop window is useful 24 hours a day, optimising its use, showing static images with a high contrast during the hours with a high lightning level and dynamic images during the hours with a low lightning level.

Claims

C L A I M S

1. System for representing images comprising a transparent layer (1), a back projection screen (2) back to back with one side of said layer (1) and a projector

(3), said layer (1) and said screen (2) separating an internal space (4) from an external space (5), the projector (3) being placed at the internal side (4), characterised in that it comprises a micro-perforated poster (6) back to back with said layer (1) by the external side (5) .

2. System for representing images according to claim 1, characterised in that the optical transmittance of said screen (2) is such that with a low lightning level by the external side (5), the images projected by said projector (3) are clearly distinguished.

3. System for representing images according to claim 1, characterised in that said screen (2) is an adhesive film or a methacrylate film.

4. System for representing images according to claim 1, characterised in that said micro-perforated poster (6) is of an adhesive kind.

5. System for representing images according to claim 1, characterised in that said projector (3) is of the specific kind for intensive use.

6. System for representing images according to claim 1, characterised in that it comprises an adhesive film with interactive technology sensitive to pressures exerted by the external side (5) placed between the back projection screen (2) and the transparent layer (1).