WO2009060253A1

WO2009060253A1 - Lighted subway signage

Info

Publication number: WO2009060253A1
Application number: PCT/IB2007/003541
Authority: WO
Original assignee: Innovative Media Solutions
Priority date: 2007-11-09
Filing date: 2007-11-09
Publication date: 2009-05-14
Also published as: CN101874264A

Abstract

An apparatus and method for displaying back-lighted images to viewers moving along a path of travel past viewing boxes containing transparent images illuminated by substantially vertical light sources of narrow width relative to the transparent images, the light sources being located behind the transparent images, relative to the viewer. The light source can be a series of LEDs or fluorescent or neon tubes, and a vertical slit can be used to reduce the width of their output. The back-lighted images can have the appearance of either a still image or produce the effect of moving images and the transparent images can be displayed on a video display remotely updatable by an update signal which may be wireless or wired generated based upon a preselected criterion such as time or detection of movement and the update signal can cause the transparent images to change to different images so that different viewers moving past the viewing box at different times see different images. Viewing boxes can have multiple images and vertical light sources. Transparent images can be displayed on video displays so they can be individually adjusted remotely vertically and horizontally to make images register, image to image, and the transparent video display image can be adjusted in its width to compensate for changes in speed of viewers moving along the path of travel past the display.

Description

LIGHTED SUBWAY SIGNAGE

Field of the Invention

The present invention is in the field of graphic displays viewed by persons rapidly moving past them, such as passengers in a subway car or a train.

Background of the Invention

Advertising is a pervasive fact of today's world. It seems as if it appears everywhere and advertisers are always looking for new ways to get their message across and attract the attention of target audiences. Indeed, industries have grown up around advertising in various media, including new, specialized media, as well as around new ways of advertising, product placement, and so on.

It has long been known that subways and trains present an advertising opportunity. A subway or train is filled with passengers and they often go through tunnels not visible to the outside world. This means that signage in such tunnels presents a rather unique advertising opportunity. A sign in such a location will have a captive audience as riders pass by it and locating signage in such tunnels will not generate the same types of concerns that often arise in connection with billboards and other signage in open, public places, which often is subject to regulation. However, there are some difficulties with such signage, such as access for changing the signs, lighting, size and the need to catch the attention of riders, especially when they are passing through a tunnel at a relatively high rate of speed.

One idea that has been around for quite some time is the idea of using the speed of a subway train to create the appearance of a moving picture by use of a series of fixed still frames. This can be analogized to motion pictures in the pre digital age when motion pictures relied upon a series of still photographs on film projected in rapid succession onto a screen by a movie projector, which, with persistence of vision, produced the effect of moving images. However, unlike 30 motion pictures, the screen in a subway tunnel is not fixed. It is, instead the movement of the train past a series of pictures fixed on the subway wall that is roughly analogous to the movie projector by providing the rapid succession of images to the viewer.

This means that the series of pictures must be correctly spaced on the subway wall, and lighted, and the pictures must be created to take into account distortions caused by the speed of the train relative to the fixed images. This, in turn, has created many challenges, and a great many inventors have sought to address such challenges for a long time. For example, in U.S. Patent No. 2,299,731, issued in 1942, a display system for moving vehicles is described which provides for illumination of a series of displays by successive brilliant flashes of light of extremely short duration. Roughly thirty years later, stroboscopic systems for display were disclosed in U.S. Patent Nos. 3,694,062 and 3,951,529 while U.S. Patent No. 3,704,064 disclosed a flash tube for use in a subway signage animation system. One of the problems with such systems was high cost, and U.S. Patent No. 4,393,742, issued in 1983, sought to reduce such cost by using a sensor to measure the velocity of a train and then initiate the flash cycle based upon the results of the sensor. Another problem with such systems was the triggering mechanism for illuminating the series of displays, and one invention directed to this problem is U.S. Patent No. 5,108,171, issued in 1992. With the dawning of the new millennium, a number of new patents have issued in the art of subway signage. U.S. Patent No. 6,169,368 discloses the use of a sensor to activate a controller upon the approach of a train to trigger an electronic display mechanism controlled by a computer. U.S. Patent No.6,353,468 discloses use of flat screen LED monitors in the display. U.S. Patent No. 6,466,183 discloses a video display apparatus. U.S. Patent No. 6,870,596 discloses a subway movie/entertainment medium and news reports indicate that the company which owns this patent, Sidetrack Technologies Inc., has installed its system in a number of subways throughout the world.

Thus, it is clear that there is a need and demand for subway signage systems and this is a medium of advertising that has drawn considerable attention, including commercial attention, over the years.

In U.S. Patent No. 6,564,486, issued in 2003 to Spodek et al. ("Spodek"), an approach to subway signage is disclosed which is analogous to a zoetrope for use in subway signage systems in an attempt to overcome problems associated with stroboscopic displays, such as timing. Spodek uses a display in which a series of still pictures are viewed through a slitboard mounted between the images and the viewers in a train. The details and math associated with such a display are discussed in rather great detail in Spodek and will not be repeated herein, but simply incorporated herein by reference for use as part of the background to the present invention. The technology of Spodek has been licensed to a company named Submedia and it has advertising systems that are now located in some of the world's top media markets, including New York, Washington, D.C., Chicago, Atlanta, Boston, Hong Kong, Tokyo and Mexico City,

The present invention seeks to advance the art of subway signage by advancing the teachings of Spodek through use of novel apparatus and methods that greatly increases the efficiency and ease of use of subway signage systems according to the teachings of the present invention.

SUMMARY OF THE INVENTION

The present invention is generally directed to an apparatus and method for displaying a visual message to a viewer moving along a path of travel past one or more viewing boxes, each containing transparent image(s) illuminated by a substantially vertical light source of narrow width relative to the transparent image(s), the light source(s) being located in the viewing box behind the transparent image(s).

In a first, separate group of aspects of the present invention, the back-lighted image(s) can have the appearance of either a still or moving image. The image(s) can be displayed on a video display (such as an LCD video) display which can be updated remotely from the box(es) by an update signal (which may be delivered as either a wireless or wired signal) while the update signal can be generated based upon a preselected criterion such as a time interval or detection of movement and the update signal can cause the images of the box(es) to change to different images so that different viewers moving past the viewing box(es) at different times will see different images. When multiple images are provided by a video display, the transparent video display images can be individually adjusted remotely vertically and horizontally to make images register, image to image, and the transparent video display images can be adjusted in width to compensate for changes in speed of viewers moving along the path of travel past the images.

In another, separate group of aspects of the present invention, the transparent image may be a photographic film, a transparency (that might, for example, be printed on a computer printer) or a planar sheet of material, any and all of which are reversed right-to-left (to compensate for the scanning light source being behind the image) which can be properly aligned through use of registration pins while the light source may be a fluorescent lamp, a neon tube or a column of light emitting diodes (which may also include a diffuser that diffuses in the vertical direction) that has the effect of sequentially illuminating vertical columns of the transparent image in a direction of travel of the viewer as the viewer moves past the viewing display. When multiple transparent images are contained in a single viewing box, an optional baffle can be used between adjacent vertical light sources.

Accordingly, it is a primary object of the present invention to provide improved backlighted images for viewers moving rapidly past such back-lighted images that rely upon a vertical light source to provide a line scan of a transparent image located between the light source and viewers. This and further objects and advantages will be apparent to those skilled in the art in connection with the drawings and the detailed description of the preferred embodiment set forth below.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 depicts a series of viewing boxes according to the present invention arranged in series in a subway tunnel.

Fig. 2 is a top view depiction of a viewing box according to the present invention showing the horizontal field of illumination of a single vertical light source. Fig. 3 is a frontal view illustrating the viewing box of Fig. 2.

Fig. 4 is a top view depiction of a series of viewing boxes according to the present invention, each of the viewing boxes having multiple vertical light sources and transparent images (not shown) which can be separated by an optional baffle.

Fig. 5 is a frontal view illustrating the series of viewing boxes of Fig. 4 without baffles. Fig. 6 is an illustrative drawing of a viewing box according to the present invention illustrating the viewing box being opened so as to install a film image. Fig. 7 is illustrative of a viewing box according to the present invention using either a film image of Fig. 6 or a video screen, without its typical backlight and Omni-directional diffuser.

Fig. 8 is an illustrative cross-sectional top view depiction of a viewing box according to the present invention using a neon tube as a substantially vertical light source illuminating image I on film F with the field of illumination illustrated by light rays LR at the outer boundaries. Fig. 9 is an illustrative cross-sectional side view taken along line 9-9 of Fig. 8 that also illustrates, in phantom, opening of hinged frame HF.

Figs. 10 and 11 are similar to Figs. 8 and 9 except that the substantially vertical light source is a miniature fluorescent lamp and hinged frame HF is not illustrated as opening in phantom lines. Figs. 12 and 13 illustrate an alternative embodiment to the embodiment depicted in Figs.

10 and 11 in which a conventional fluorescent lamp is located behind a wail having a slit S so as to create a substantially vertical light source of narrow width relative to the transparent image I on film F.

Fig. 14 is similar to Fig. 10 except that the substantially vertical light source is a column of light emitting diodes (LEDs) with a vertical diffuser D.

Fig. 15 is similar to Fig. 11, based upon the embodiment shown in Fig. 14, except that portions of the structure illustrated in Fig. 16 have been removed.

Fig. 16 is a partial side depiction of a column of LEDs shown in Fig. 14. Fig. 17 is the image perceived by a viewer as a train moves rapidly past multiple back lighted images according to the present invention. The vertical sides appear smeared due to the motion of the train past the light boxes.

DESCRIPTION OF THE INVENTION

The present invention provides a lighted subway system that is much more energy efficient, and thus less costly, than prior lighted subway systems. The display of the present invention simulates the experience of a train rider who is viewing the scene out of the train window, passing distant landscapes, mountains, landscapes, trees, buildings etc. In this setting, the scene looks real and natural, as is the case. Even when the train might pass a tall fence or pass through a wooden covered bridge with sides of vertical slats with narrow slits between the boards, the train rider still sees the scene as the slits between the boards fly by, although a darker image because the slits occupy a small portion of the pitch distance from board to board. Example: if the boards are turned vertically and placed on 6 inch centers however have a 1 /32- inch wide gap, the brightness is reduced to 0.03125/6 = 0.5%. If the train is traveling at an adequate speed, the passing slits (or boards) will blur and will not appear to be in motion; however, the distant scene will appear normally but attenuated to 0.5% brightness.

Using the principle of a Zoetrope, viewing an image through a rapidly passing slit, it is possible to simulate the experience of the train rider by providing slits in the foreground through which lighted images are displayed behind the slit. In accordance with simple geometry and proportions, when the depth of the light box is reduced, the width of the image must be reduced in proportion. The width of the image behind the slit is such that from the train rider's viewing distance, the image width is compressed so that the width of the perceived image is in proportion to the height of the image, for example when displaying a TV commercial. Depending on train speed, in order to provide the appropriate width, the actual image must be horizontally compressed approximately 6:1 to 10:1. When the subway train is traveling fast enough, these slits blur and due to the persistence of vision, multiple images from the series of lighted images appear to superimpose one over the other. By displaying images with slight changes, an animated effect is created from these passive displays. This explains the conventional thinking on passive lighted subway signage by viewing the image through a slit. The subject of this invention however switches the foreground/background relationship of the slit and image so that the image is in the foreground and the equivalent of a slit, a narrow vertical light source, is in the background. The bare light source is viewed through the foreground image as the viewer passes the light box. The invention will now be described in connection with several especially preferred embodiments with references, where appropriate, to the Figures.

As already noted in the background of the invention, the present invention is especially well suited to use in subway tunnels where there is no natural light, where viewers are riding in a subway car at a relatively rapid speed (as compared, for example, to walking or running), and where signage has the ability to be viewed by a great many viewers as they travel through such tunnels.

A viewing box, LB, according to the present invention may have one or more transparent images, I₁ and it is especially preferred that any such image(s) be protected by a transparent cover, TC. Fig. 3 illustrates a viewing box with one image, I, while Fig. 5 illustrates a viewing box with multiple images. When multiple images are aligned in parallel along a path of travel the images can produce the effect of moving images as a viewer moves past the images.

Each transparent image I in a viewing box according to the present invention is illuminated by its own substantially vertical light source, LS, of narrow width relative to the transparent image, the light source being located in the viewing box behind the transparent image, relative to the viewer. The vertical light source provides a line scan of the image as a viewer moves past the image, in much the same way as a slit provides a similar line scan when the slit is located between the viewer and the lighted image in a device such as is disclosed in U.S.Patent No. 6,564,486 to Spodek et al. In contrast to Spodek in which the illumination is greatly attenuated by either being (1) reflected off of a front-lighted opaque print, or (2) transmitted through a back-lighted diffuser and image, both about 10% efficient, the present invention provides that the viewer is looking directly at the bare light source LS. To further illustrate the point, consider the difference in brightness of light that falls on a book from a reading lamp to looking at the bare hot tungsten filament of a clear light bulb in the reading lamp. This approximate 10:1 increase in brightness allows the subway signage of this invention to be illuminated, to the same level as Spodek, with a light source LS of approximately 10% of the energy requirements.

The vertical light source LS used in the present invention can take many forms, examples of which are illustrated in Figs. 8-15. Figs. 8 and 9 illustrate use of a narrow neon tube N. Figs. 10 and 11 illustrate use of miniature fluorescent lamp MFL. Figs. 12 and 13 illustrate use of a conventional fluorescent lamp FL, although not used efficiently, is advantageous due to the low cost and ready availability, whose output is limited by use of a wall with a slit S to create a substantially vertical light source of narrow width relative to the image I. This same concept, of limiting the width of the light source through use of a slit, can be used with other light sources as well, and it is an especially preferred way to achieve a desired narrow width vertical light source when its the cost is less than what might be required by using a very narrow vertical light source without a slit. Figs. 14 and 15 illustrate use of a column of light emitting diodes, LEDs, mounted to a printed circuit board, PCB, while Fig. 16 illustrates such a column of LEDs in an especially preferred embodiment with the addition of a diffuser D which diffuses transmitted light exclusively in a vertical direction so as to fill in the gaps between individual LEDs to create the impression of a continuous unbroken vertical line of light. In each of these light sources, the width of the light source is narrow relative to the image so that it will create a vertical line scan of the image as a viewer moves laterally past the image.

The transparent image(s) can take many forms. For example, the transparent image may be a photographic film such as Kodak® Duraclear or Endura film, a transparency (including a transparency that might be printed on a computer color printer) or a planar sheet of material (such as transparent vinyl or Mylar® that may be obtained from rolls). To insure proper alignment of such a transparency within a viewing box the transparency can include one or more markings or registration holes for alignment with one or more registration pins RP (see, e.g., Figs. 6 and 8-15) and, as is depicted in Figs. 6 and 9, the viewing box can have a hinged frame HF connected by a hinge H to allow the transparent cover to be opened for ease of replacement of any transparency it holds.

As an alternative to a physical transparent image that must be replaced when the image is changed, the transparent image can be formed by a video display, V, such as an LCD video display with its typical backlight and omni-directional diffuser and typical back light removed, or any other form of image display equivalent to such a display in the context of the present invention in which the display is lit from within the display box but can be changed (or altered) without physically changing the actual display.

One advantage of a video display over a film image is that it can be updated remotely by an update signal. Such a signal can be delivered via a wired connection or via a wireless connection (see antennae Fig. 1, A) and the update signal can be based on any number of preselected criteria, such as, for example, a time interval. In an especially preferred embodiment, the update signal can be based upon detection of movement of the train past a box. Thus, for example, as shown in Fig. 1 , a proximity sensor, PS, might be mounted on a viewing box attached to a tunnel wall, TW, for detecting movement of a train, T.

In an embodiment using a video display that can be updated remotely from the light box, the video display can be programmed so that passengers in a train or subway cars moving past it might actually see different images; in other words, passengers in the first car in a train might see a first image (such as ah advertisement) while passengers in a second car of the train might see a second image or advertisement, and so on. As a result of such flexibility, an advertiser using such a system might be charged different rates for times of peak travel or the advertiser might be charged based upon the number of cars that pass by the viewing box(es) of a particular location, all of which create far more flexibility than can be obtained by use of film image, especially since the number of potential images that can be displayed, and their sequence and timing of display, can all be controlled electronically, instead of manually.

Another advantage of a video display over a physical transparent image is that its image can be individually adjusted remotely vertically and horizontally to make images register, image to image, when multiple display boxes are being used together to create a still or animated image. This is very important because if images in a series of boxes are not properly aligned the image or images that are being viewed appear to jump around. Also, the width of transparent images can be adjusted to compensate for train speed, something that obviously cannot be done with a physical transparent image.

In connection with the present invention, it will usually be the case that multiple viewing boxes will be mounted along a path of travel past the boxes, even if the image to be displayed is only a still image. However, multiple images can be displayed in a single viewing box, as is illustrated in Figs. 1 and 5, and this is especially preferred when the image is being displayed on a video display so as to maximize the use of such display. When multiple images are displayed in a single viewing box, each of the images must be lighted by its own substantially vertical light source. In such an embodiment, as shown in Fig. 4, it may be desirable to include a baffle, B, between individual light sources. The purpose of such a baffle is to eliminate possibly distracting side images created by a light source illuminating a neighboring or adjacent image. When the vertical light source is a series of LEDs, a baffle is usually not required because the support structure which supports the printed circuit board PCB, LED's and vertical diffuser D serves the purpose of a baffle that might be used otherwise with a miniature fluorescent lamp or neon tube.

Persistence of vision is such that the images will need to be pass the viewer frequently to prevent the perception of flicker. The minimum flicker frequency is approximately 18 Hz. Preferably, lighted images need to be refreshed at or above 48 Hz. A horizontal spacing, or image pitch IF, of 2.2 feet provides 20 images per second for a train traveling 30 miles per hour. By placing images closer than 2.2 feet, a higher frame rate is achieved and the illumination appears continuous. Particularly with the more expensive LCD video displays, it is important to use them efficiently and to take advantage of available image resolution. By choosing the image pitch IF and spacing between light boxes LB carefully the image pitch IP can be made uniform between multiple images within one light box and from light box to adjacent light box as shown in Figs. 4 and 5. This assures a uniform and sufficiently high refresh rate so as to not see a vertical dark band sweep through the image as the train moves, and in general makes the image more comfortable and pleasant to view. While the invention has been described herein with reference to certain preferred embodiments, those embodiments have been presented by way of example only, and not to limit the scope of the invention. Additional embodiments thereof will be obvious to those skilled in the art having the benefit of this detailed description. Further, modifications are also possible in alternative embodiments without departing from the inventive concept. Accordingly, it will be apparent to those skilled in the art that still further changes and modifications in the actual concepts described herein can readily be made without departing from the spirit and scope of the disclosed inventions as defined by the following claims.

Claims

What is claimed is:

Claim 1 ; Apparatus for displaying a back-lighted image to a viewer moving along a path of travel past a viewing display, comprising: a viewing box; a transparent image contained in the viewing box; and a substantially vertical light source of narrow width relative to the transparent image, said light source being located in the viewing box behind the transparent image, relative to the viewer.

Claim 2: The apparatus of claim 1 , where the appearance of the back-lighted image is of a still image.

Claim 3: The apparatus of claim 1, wherein the transparent image is comprised of a video display.

Claim 4: The apparatus of claim 3, wherein the video display is comprised of an LCD video display. Claim 5: The apparatus of claim 3, wherein the transparent image can be updated remotely from the box by an update signal.

Claim 6: The apparatus of claim 3 wherein the update signal is a wireless signal.

Claim 7: The apparatus of claim 5 wherein the update signal is a wired signal.

Claim 8: The apparatus of claim 1 wherein the transparent image is selected from the group consisting of a photographic film, a transparency and a sheet of planar material.

Claim 9: The apparatus of claim 8, wherein the transparent image is properly aligned within the viewing box by use of one or more registration pins.

Claim 10: The apparatus of claim 1, wherein the substantially vertical light source is selected from the group consisting of a fluorescent lamp and a neon tube. Claim 11: The apparatus of claim 1, wherein the substantially vertical light source is comprised of a column of light emitting diodes.

Claim 12: The apparatus of claim 11, further comprising a diffuser for diffusing light vertically from the column of light emitting diodes.

Claim 13: The apparatus of claim 1, wherein the substantially vertical light source is created by a slit between a light source and the transparent image.

Claim 14: The apparatus of claim 1, wherein the vertical light source is visible sequentially behind vertical columns of the transparent image in a direction of travel of the viewer as the viewer moves past the viewing display. Claim 15: The apparatus of claim 14, wherein the transparent image is reversed right-to- left to compensate for the scanning light source being behind the (transparent image).

Claim 16: The apparatus of claim 1 , further comprising: a plurality of transparent images contained in the viewing box; and a plurality of substantially vertical light sources of narrow width relative to the plurality of transparent images, said plurality of substantially vertical light sources being located in the viewing box behind the plurality of transparent images, relative to the viewer, each of the plurality of transparent images having one of the plurality of substantially vertical lights sources located behind it.

Claim 17: The apparatus of claim 16, further comprising: at least one baffle located between two of the plurality of substantially vertical light sources. Claim 18: The apparatus of claim 1 , further comprising: a plurality of the viewing displays aligned parallel to a path of travel with the plurality of transparent images so as to create an effect of moving images as the viewer moves past the plurality of the viewing displays.

Claim 19: A method for displaying a back-lighted image to one or more viewers moving along a path of travel past a viewing display, comprising the steps of: placing a viewing box with a transparent image parallel to the path of travel; and illuminating the transparent image with a substantially vertical light source of narrow width relative to the transparent image, said light source being located in the viewing box behind the transparent image, relative to the viewer.

Claim 20: The method o claim 19, wherein the transparent image is comprised of a video display.

Claim 21: The method of claim 20, wherein the transparent video display image can be individually adjusted remotely vertically and horizontally to make images register, image to image.

Claim 22: The method of claim 21 , wherein the transparent video display image can be adjusted in its width to compensate for changes in speed of one or more viewers moving along the path of travel.

Claim 23: The method of claim 22, wherein the transparent image can be updated remotely from the box by an update signal.

Claim 24: The method of claim 23, comprising the further steps of: changing the transparent image based upon a preselected criterion.

Claim 25: The method of claim 24, wherein the preselected criterion is based upon a preselected time interval. Claim 26: A method for displaying a plurality of back-lighted images to a plurality of viewers moving along a path of travel past the plurality of back-lighted images so as to produce an effect of moving images, comprising the steps of: placing one or more viewing boxes in the path of travel; and illuminating each of a plurality of transparent images held in the one or more viewing boxes with a substantially vertical narrow light source as the viewer moves in the path of travel past the one or more viewing boxes; wherein each of the substantially vertical narrow light sources is located behind one of the plurality of transparent images relative to the viewer.

Claim 27: The method of claim 26, wherein each of the plurality of transparent images can be updated remotely by an update signal. Claim 28: The method of claim 27, comprising the further step of: generating the update signal based upon detection of movement past one of the plurality of viewing boxes.

Claim 29: The method of claim 28, wherein the update signal causes the transparent image contained in a selected set of the plurality of transparent images to change from a first image to a second image. Claim 30: The method of claim 29, wherein a first group of the plurality of viewers views the first image and a second group of the plurality of viewers views the second image.