WO2013020270A1

WO2013020270A1 - A light-tight and collapsible chamber for demonstrating the optical performance of reflective materials

Info

Publication number: WO2013020270A1
Application number: PCT/CN2011/078153
Authority: WO
Inventors: Bo Guo; Rui Chen; Weilin Shi; Xiaoxian LI; Yongping ZHU; Yu Chen; Lingbo ZHENG; Ying Shen; Shaoqing GU; Yichun SHAO
Original assignee: 3M Innovative Properties Company
Priority date: 2011-08-09
Filing date: 2011-08-09
Publication date: 2013-02-14
Also published as: CN103732097B; CN103732097A

Abstract

A light-tight and collapsible chamber (120, 300) for use in demonstrating the optical performance of a piece of retroreflective sheeting placed within the chamber (120, 300) is provided. The chamber (120, 300) comprises a generally opaque polygonal back panel (130, 320) having a plurality of edges; a plurality of generally opaque side panels (140, 170) wherein adjacent side panels (140, 170) are attached to one another to form a light-tight connection and each of the plurality of opaque side panels (140, 170) are attached along and positioned essentially perpendicular to one of the plurality of edges of the back panel (130, 320) to form a light-tight connection; and an open area (150, 330) essentially parallel to and distanced from the back panel (130, 320) and forming an observation window permitting an observer to view the piece of retroreflective sheeting positioned within the chamber (120, 300). In one embodiment, the chamber (120, 300) further comprises a leaflet (310) capable of attaching to the piece of retroreflective sheeting attached to the back panel (130, 320). In another embodiment, the chamber (120, 300) can be collapsed in various ways.

Description

A Light-Tight and Collapsible Chamber for Demonstrating the Optical Performance of

Reflective Materials

Background

Reflective materials are used in traffic safety systems, consumer markets, personal safety products, solar energy systems, and many other areas. It is often desirable to demonstrate the optical performance of reflective materials. Such demonstrations are typically done in either ambient light with a light source (see, for example, those described in U.S. Patent Publication No. 201 1 -0069317) or in darkrooms that can be made completely dark to allow the processing of light sensitive photographic materials, including photographic film.

Retroreflective materials have the ability to redirect light incident on the material back toward the originating light source. This property has led to the widespread use of retroreflective sheeting for a variety of traffic and personal safety uses. Retroreflective sheeting is commonly employed in a variety of articles (e.g., road signs, barricades, license plates, pavement markers, and pavement marking tape, as well as retroreflective tapes for vehicles and clothing). The optical performance (e.g., retroreflectivity) of retroreflective sheeting is typically measured in dedicated facilities, such as in a large darkroom, a room with controlled light sources, or in an open facility with the demonstration carried out at night.

Summary

In one embodiment, a light-tight, collapsible chamber for use in demonstrating the optical performance of a piece of retroreflective sheeting placed within the chamber includes a generally opaque polygon back panel, a plurality of generally opaque side panels, a leaflet attached to the back panel along an edge of the leaflet, and an open area essentially parallel to and distanced from the back panel. The back panel has a plurality of edges. Eveiy two adjacent panels of the plurality of generally opaque side panels are configured to attach to one another with a light-tight connection. Each of the plurality of generally opaque side panels is connected along and positioned essentially perpendicular to one of the plurality of edges of the back panel with a light-tight connection. The piece of retroreflective sheeting is configured to be attached to the piece of the leaflet. The open area forms an observation window permitting an observer to view the piece of retroreflective sheeting positioned within the light-tight, collapsible chamber. In another embodiment, a light-tight, collapsible chamber for use in demonstrating the optical performance of a piece of retroreflective sheeting placed within the chamber includes a generally opaque back panel including an upper edge, a lower edge, a left edge, and a right edge; a generally opaque upper panel connected along and positioned generally perpendicular to the upper edge of the back panel; a generally opaque lower panel connected along and positioned generally perpendicular to the lower edge of the back panel; two generally opaque side panels connected along and positioned generally perpendicular to one of the left edge and the right edge of the back panel respectively; and an open area essentially parallel to and distanced from the back panel that forms an observation window permitting an observer to view the piece of retroreflective sheeting positioned within the light-tight, collapsible chamber. The upper panel is positioned essentially parallel to the lower panel. The two side panels are positioned essentially parallel to one another. The upper panel is connected to the two side panels. The lower panel is connected to the two side panels. The connections between the generally opaque panels provide a light-tight connection. If the light-tight, collapsible chamber is collapsed, the two side panels are configured to be detached from the back panel and the upper panel and folded onto the lower panel, the upper panel is configured to be folded onto the back panel, and the back panel together with the upper panel is folded onto the lower panel.

In yet another embodiment, a light-tight, collapsible chamber for use in demonstrating the optical performance of a piece of retroreflective sheeting placed within the chamber, includes a generally opaque back panel including an upper edge, a lower edge, a left edge, and a right edge; a generally opaque upper panel connected along and positioned generally perpendicular to the upper edge of the back panel; a generally opaque lower panel connected along and positioned generally perpendicular to the lower edge of the back panel; two collapsible generally opaque side panels connected along and positioned generally perpendicular to one of the left edge and the right edge of the back panel, each of the two side panels having a folding line; and an open area essentially parallel to and distanced from the back panel that forms an observation window permitting an observer to view the piece of retroreflective sheeting positioned within the light- tight, collapsible chamber. The upper panel is positioned essentially parallel to the lower panel and the two side panels are positioned essentially parallel to one another. The upper panel is connected to the two side panels. The lower panel is connected to the two side panels. The connections between the generally opaque panels provide a light-tight connection. If the light- tight, collapsible chamber is collapsed, the back panel is configured to be detached from the upper panel and the two side panels; the two side panels are configured to be folded along the folding line on the panel and folded onto the lower panel respectively; the upper panel is configured to be folded onto the two side panels; and the back panel is configured to be folded onto the upper panel.

Brief Description of the Drawings

The accompanying drawings are incorporated in and constitute a part of this specification and, together with the description, explain the advantages and principles of the invention. In the drawings,

Figures 1 A and IB illustrate an exemplary embodiment of transforming a briefcase to a light-tight and collapsible chamber;

Figure 2A illustrates an exemplary embodiment of a light-tight connection formed by magnetic means;

Figure 2B illustrates an exemplary embodiment of a light-tight connection formed by folding means;

Figure 3 illustrates a top view of an exemplary embodiment of a light-tight and collapsible chamber with the upper panel lifted;

Figure 4 illustrates how a light-tight and collapsible chamber may be used during a demonstration;

Figure 5A is a perspective view of an exemplary embodiment of a light-tight and collapsible chamber having a rectangular back panel;

Figure 5B is a front view of the exemplary embodiment of the light-tight and collapsible chamber in Figure 5A;

Figure 6A is a perspective view of an exemplary embodiment of a light-tight and collapsible chamber having a hexagonal back panel;

Figure 6B is a front view of the exemplary embodiment of the light-tight and collapsible chamber in Figure 6A;

Figure 7A is a perspective view of an exemplary embodiment of a light-tight and collapsible chamber in cylindrical shape that is assembled from a collapsed case;

Figure 7B is a front view of the exemplary embodiment of the light-tight and collapsible chamber in Figure 7A; Figures 8A-8F illustrate an exemplary embodiment of a light-tight and collapsible chamber and the assembly process of setting up the light-tight and collapsible chamber;

Figures 9A-9D illustrate an exemplary configuration to assemble a light-tight and collapsible chamber;

Figure 10A illustrates an exemplary embodiment of a light-tight and collapsible chamber having more than one pieces of leaflet; and

Figure 10B illustrates another exemplary embodiment of a light-tight and collapsible chamber. Detailed Description

The present disclosure generally relates to a portable system in which the optical characteristics of reflective objects can be demonstrated. For example, a sales person wishing to demonstrate the optical performance of reflective products such as, for example, retroreflective sheeting, can quickly create a small darkroom in which the product's optical performance can be demonstrated. The present disclosure is directed to an apparatus for a light-tight and collapsible chamber for use in demonstrating the optical characteristics and performance of reflective materials placed within the chamber and the chamber having an open area allowing an observer to view the reflective materials. In some embodiments, a light source can be used to direct light to the object placed within the chamber through the open area to facilitate the testing and demonstration of the optical performance of the object.

Different embodiments of the light-tight and collapsible chamber are compact and easy to carry, store, and transport. Additionally, different embodiments of a light-tight and collapsible chamber can operate in an environment with lights (i.e., ambient lights, sun lights, etc.).

Different embodiments of a light-tight and collapsible chamber may be designed to filter out about 70% environmental lights to facilitate the demonstration of the optical performance of reflective materials placed inside the chamber.

Figures 1A and I B illustrate one exemplary embodiment of a light-tight and collapsible chamber. These figures show the process of transforming a briefcase 1 10 into a light-tight and collapsible chamber 120. The briefcase 1 10 can be any type of portable and flat container. In some embodiments, the briefcase 1 10 may have two covers, as illustrated in Figure 1A, one upper cover 1 12 and one lower cover 1 14. The briefcase 1 10 shown in Figure 1A is shorter in height comparing to the overall length of the covers. Those of skill in the art will appreciate that the briefcase covers may have shapes other than those specifically shown in the Figures of the present disclosure, for example, square, hexagon, round, ellipse, etc. In some implementations, the briefcase 1 10 can be closed by a zipper. The briefcase 1 10 may include a plurality of panels to assemble the light-tight chamber 120. In some embodiments, the chamber 120 may comprise a back panel 130, a plurality of side panels 140, and an open area 150. Those of skill in the art will appreciate that the back panel may have shapes other than those specifically shown in the Figures of the present disclosure, for example, square, hexagon, round, ellipse, etc. In some implementations, the back panel can be a polygon having a plurality of edges.

In some embodiments, the plurality of side panels includes a lower panel 170. Adjacent panels of the plurality of side panels are configured to attach to each other with an essentially light-tight connection. Each of the plurality of side panels can be connected along and positioned, for example, essentially perpendicular to one of the plurality of edges of the back panel with a light-tight connection. The panels of the chamber 120 can be made by material that allows limited amount of light to pass through. In some embodiments, the panels of the chamber 120 can be opaque panels. The open area 150 is essentially parallel and distanced from the back panel 130. The open area 150 can form an observation window permitting an observer to view objects positioned within the chamber 120. In some cases, the open area 150 may occupy a portion of a front panel (not shown in Figure IB). In some other cases, the chamber 120 does not have a front panel (not shown in Figure IB).

As used herein, the term "light-tight connection" is used to refer to a connection that can block a majority of light. The light-tight connection can be formed by any connection means, for example, magnetic means, folding means (i.e. seams formed through ultrasonic or radio frequency welding, etc.), adhesive means, fasteners, or the like. In some implementations, the panels can be designed with mechanical structures or materials to facilitate the construction of the light-tight connections. For example, a panel can include a magnetic strip to facilitate connection. In some other implementations, additional parts may be added to form the light-tight connections. For example, a magnetic strip can be attached to a panel to form a light-tight connection when a chamber is assembled.

Figure 2A illustrates an exemplary embodiment of a light-tight connection formed by magnetic means. In one embodiment, a panel 210 may include a foldable magnetic strip 220. At least a portion of another panel 230 is made of material that can be attracted by magnets. A light- tight connection can be formed by placing the strip 220 over the portion of the panel 230 that can be attracted by magnets, as illustrated in Figure 2A.

Figure 2B illustrates an exemplary embodiment of a light-tight connection formed by folding means. In some implementations, a panel 240 can be folded into a first portion and a second portion along a folding line 250 crossing the width of the panel 240, while the folding line is positioned between two opposing edges 260 and 270 and the first portion can be folded over the second portion. A folding line is typically made of a flexible material. In some other implementations, two adjacent panels having a folding line between the two panels can be folded such that one panel can be laid on top of the other panel to form a panel stack. When some embodiments of a light-tight and collapsible chamber are disassembled, a panel stack can be formed while the order of folding panels may vary. In these embodiments, the first panel folded over a second panel may refer to the first panel folded onto a panel stack including the second panel. In other implementations, two opposing panels of the light-tight, collapsible panel can be folded along a folding line on each panel respectively at the same time, as illustrated in Figure 9C.

In some embodiments, a light-tight and collapsible chamber may be assembled using more than one type of light-tight connections. For example, a light-tight and collapsible chamber may be assembled using both magnetic means and folding means.

Figure 3 illustrates a top view of an exemplary embodiment of a light-tight and

collapsible chamber 300 with the upper panel lifted. The light-tight and collapsible chamber includes a back panel 320. In a particular embodiment, the light-tight and collapsible chamber 300 has one or more leaflets 310 attached to the back panel .320. The one or more leaflets 310 may be attached to the back panel 320 by any type of fastener, for example, by rivets, screws, nails, hook and loop, adhesive, magnets, etc. A piece of reflective sheeting can be attached to a leaflet. In some configurations, the one or more leaflets 310 may provide one or more pockets into which retroreflective sheeting can be placed. In some other configurations, a piece of retroreflective sheeting may be attached to one of the leaflets 310 by any type of fastener. The light-tight and collapsible chamber 300 may have an open area 330 essentially parallel and distanced from the back panel 320. In some implementations, one of the leaflets 310 may be placed at an angle 340 from the back panel 320. The angle 340 can be changed depending on the position of the leaflets 310. With such configurations, the chamber 300 can be used to demonstrate the sheeting at various viewing angles. Figure 4 illustrates how a light-tight and collapsible chamber 400 may be used during a demonstration. An observer 410 may stand at a distance D away from the light-tight and collapsible chamber 400. The chamber 400 may be place at a height of H for demonstration purpose. In some embodiments, the height H may be in the range of 3 feet to 8 feet, with a range of 5 feet to 6 feet preferred. In a particular embodiment, the light-tight and collapsible chamber 400 is used for demonstrating optical performance of one or more pieces of retroreflective sheeting. The observer 410 may hold a light source 420 to direct light onto retroreflective sheeting placed inside the chamber 400. The light source 420 can be, for example, a flashlight, an electrical torch, or the link. The light source 420 may provide visible lights, ultraviolet lights, or lights in other wavelength depending on the demonstration or testing needs. In order to observe the optical performance of retroreflective sheeting, an observer may stand at a position that is sufficiently far from the chamber 400. The threshold distance for observation is referred to as an optimal distance. The observer may stand at a position having D greater than the optimal distance to obtain a good observation result. Table 1 provides a list of exemplary optimal distance versus the size of the retroreflective sheeting. It is noted that the observer 410 is typically not standing at least 1.5 feet from the chamber 400.

Table 1

In demonstrating the optical performance of a piece of retroreflective sheeting, the angle formed by a line between the light source 420 and the piece of retroreflective sheeting and the line between the human eyes of the observer 410 and the piece of retroreflective sheeting is ideally no more than 2 degrees. In some implementations, the light source 420 may be placed close to the nose of the observer 410 to simulate a situation in which a driver is reading a traffic sign from a sedan. In some other implementations, the light source 420 may be placed close to the forehead of the observer 410 to simulate a situation in which a driver is reading a traffic sign from a sports utility vehicle. In yet other implementations, the light source 420 may be placed close to the chin of the observer 410 to simulate a situation in which a driver is reading a traffic signs from a truck.

Figure 5 A is a perspective view of an exemplary embodiment of a light-tight and collapsible chamber 500. In some embodiments, the light-tight and collapsible chamber 500 can be collapsed into a briefcase. In some embodiments, the light-tight and collapsible chamber 500 has a back panel 510, an upper panel 520, a lower panel (not shown in Figure 5 A), and two side panels 530 (one side panel not shown in Figure 5A). The back panel 510 can be in any shape, as is described above. The specific shape shown in these figures is rectangular. In a particular embodiment, the lower panel is part of the cover 540 of a briefcase when the light-tight and collapsible chamber 500 is disassembled. The back panel 510 can have three magnetic strips 560 that are foldable. When the light-tight and collapsible chamber 500 is assembled, one of the magnetic strips is attached to the upper panel 520 and the other two are attached to one of the side panels 530 respectively. In some implementations, the side panels 530 can be folded along a folding line 570 when the light-tight and collapsible chamber 500 is disassembled.

Figure 5B is a front view of the exemplary embodiment of the light-tight and collapsible chamber 500 in Figure 5A. In some embodiments, the light-tight and collapsible chamber 500 may include an open area 580 essentially parallel and distanced from the back panel 510. A piece of retroreflective sheeting 550 can be placed inside the light-tight and collapsible chamber 500. The piece of retroreflective sheeting 550 can be viewed through the open area 580.

Additionally, an external light source can be used to direct light on the piece of retroreflective sheeting 550 through the open area 580 to demonstrate the optical performance of the piece of retroreflective sheeting 550.

Figure 6A is a perspective view of an exemplary embodiment of a light-tight and collapsible chamber 600 having a hexagonal back panel. In some embodiments, the light-tight and collapsible chamber 600 may have a hexagonal back panel 610 and six pieces of side panels 620 (some not shown in Figure 6A). In some implementations, each one of the side panels 620 can be positioned along and positioned essentially perpendicular to one of the six edges of the back panel 610. In some implementations, the back panel can have six pieces of magnetic strips 630. Each of the magnetic strips 630 can be attached to one of the side panels 620 respectively. When the chamber 600 is collapsed, the back panel 610 can be detached from five side panels except a lower panel, the three upper side panels can be collapsed and laid over the three lower side panels, and the back panel 610 can be folded over the side panels. Figure 6B is a front view of the exemplary embodiment of the light-tight and collapsible chamber 600 of Figure 6A. In some implementations, the light-tight and collapsible chamber 600 includes an open area 640 that is essentially parallel and distanced from the back panel 610. A piece of retroreflective sheeting 650 can be placed within the light-tight and collapsible chamber 600. The piece of retroreflective sheeting 650 can be viewed through the open area 640. Additionally, a light source that is outside of the light-tight and collapsible chamber 600 can be used to direct light onto the piece of retroreflective sheeting 650 through the open area 640.

Figure 7A is a perspective view of an exemplary embodiment of a light-tight and collapsible chamber 710 in cylindrical shape that is assembled from a collapsed case 700. In some embodiments, the light-tight and collapsible chamber 710 includes a round-shaped back panel 720 and a side panel 730. In some embodiments, the side panel 730 can be collapsed along a series of folding lines. The back panel 720 can be in other shapes, including, for example those shapes mentioned above.

Figure 7B is a front view of another exemplary embodiment of the light-tight and collapsible chamber 710. In some implementations, the light-tight and collapsible chamber 710 may include an open area 740 essentially parallel to and distanced from the back panel 720. A piece of retroreflective sheeting 750 can be placed within the light-tight and collapsible chamber 700. The piece of retroreflective sheeting 750 can be viewed through the open area 740.

Additionally, a light source that is outside of the light-tight and collapsible chamber 700 can be used to direct light on the piece of retroreflective sheeting 750 through the open area 740.

Figures 8A-8F illustrate an exemplary embodiment of a light-tight and collapsible chamber 800 and the assembly process of setting up the light-tight and collapsible chamber 800. Referring to Figure 8A, a portable briefcase 800 includes a first portion 802 connected to a second portion 804. The connecting part of the first portion 801 and the second portion 804 can be made, for example, of a flexible material, such that the first portion 802 can be, for example, folded over the second portion 804 when the portable briefcase 800 is closed. When the portable briefcase 800 is open, the first portion 802 can form an angle of generally 90 degrees to the second portion 804 at their connecting part. In some implementations, the portable briefcase 800 can be closed by a zipper or other closing mechanism. In this particular embodiment, five essentially rectangular opaque panels are included in the briefcase 800. Each panel comprises an upper edge, a lower edge, a left edge, and a right edge. In one embodiment, as illustrated to Figure 8A, an edge of an generally opaque upper panel 820 is attached to the first portion 802 by any connection means to form a hinge. A back panel 810 is laid generally flat in the second portion 804 of the briefcase 800. Referring to Figure 8B, the opaque upper panel 820 can be lifted. Referring to Figure 8C, a back panel 810 is attached to the first portion 802 by any attachment means to form a hinge. Optionally, one or more leaflets 850 are attached to the back panel 810 by any attachment means, including, for example, those described above. After the back panel 810 is lifted, a right-side panel 830 can be seen as laid generally flat in the second portion 804 of the briefcase 800.

Referring to Figure 8D, the right edge of a generally opaque right-side panel is connected along the right edge of the lower panel by any connection means, for example, by ultrasonic welding, to form a hinge. The right-side panel 830 can be lifted and positioned essentially perpendicular to the back panel 810 and the second portion 804 of the brief case 800. The right- side panel 830 can be attached to the back panel by any connection means, for example, those described above. After the right panel 830 is lifted, the left-side panel can be laid generally flat in the second portion 804 of the briefcase 800. Referring to Figure 8E, the right edge of a generally opaque left-side panel is connected along the left edge of the opaque lower panel by any connection means, for example, by ultrasonic or radio frequency welding, to form a hinge. In some implementations, a lower panel 860 can be attached to the second portion 804 of the portable briefcase 800 by any connection means, for example, those described above. In some other implementations, the lower panel 860 can be an integrated part of the second portion 804 of the briefcase 800.

Referring to Figure 8F, the left-side panel 840 can be lifted and positioned essentially perpendicular to both the back panel 810 and the lower panel 860. The left-side panel 830 can be attached to the back panel by any connection means, for example, by those described above. The lower panel 860 is positioned generally along the lower edge of the back panel. The upper panel 820 can be connected to the left-side panel 840, the right-side panel 830, and the back panel 810 by any connection means, for example, by those described above. An open area 870 can be formed at a position essentially parallel to and distanced from the back panel 810. Thus, a light- tight and collapsible chamber 880 is assembled. A piece of retroreflective sheeting can be disposed within the light-tight and collapsible chamber 880. In some implementations, the piece of retroreflective sheeting can be attached to the leaflet 850. The opening area 870 is designed to permit an observer to view the piece of retroreflective sheeting with the aid of a light source directing light through the open area 870.

When the light-tight and collapsible chamber 880 is disassembled, the upper panel can be detached from the back panel 810, the left-side panel 840, and the right-side panel 830; the left- side panel 840 and the right-side panel 830 can be folded over the lower panel 860; the back panel 810 along with the leaflet 850 can be folded over the lower panel 860; the upper panel 820 can be folded into the first portion 802 of the briefcase 800; the first portion 802 can be folder over the second portion 804; and optionally, the briefcase 800 can be closed, for example, by zipper.

Figures 9A-9D illustrate an exemplary configuration to assemble a light-tight and collapsible chamber. Referring to Figure 9A, a portable briefcase 900 including a first portion 902 and a connecting second portion 904 is provided. The connection part between the first portion 902 and the second portion 904 is made of a flexible material, such that the first portion 902 can be folded over the second portion 904 when the portable briefcase 900 is closed. When the portable briefcase 900 is open, the first portion 902 can be laid generally flat with the second portion 904. In some implementations, the portable briefcase 900 can be closed by, for example, a zipper. In a particular embodiment, the portable briefcase 900 includes three generally opaque panels and two collapsible generally opaque panels. Each panel includes an upper edge, a lower edge, a left edge, and a right edge. Each collapsible panel further includes a folding line 990 running the entire width of the panel, as generally shown in Figure 9C. In some cases, the folding line 990 of a collapsible generally opaque panel can be a vertically mid-line. When collapsed, the collapsible panel folds into two portions - a first portion and a second portion. The folding line may be thinner than the panel itself and is preferably made of a flexible material. A magnetic strip, for example, with a width of approximately 0.5 in (1.27 cm), can be used as connecting means. Those of skill in the art will appreciate that other connecting means can be used and are within the scope of the present application.

Referring to Figure 9B, a generally opaque back panel 910 is connected to an edge of the first portion 8902 of the briefcase 900 to form a hinge. The back panel 910 can be lifted and positioned essentially perpendicular to the first portion 902 of the briefcase 900. Optionally, one or more leaflets 950 can be attached to the back panel 910 by any connection means, including for example, those discussed above. After the back panel 910 is lifted, an upper panel 920 can be seen as laid generally flat in the first portion 902 of the briefcase 900. Referring to Figure 9C, a generally opaque lower panel 940 is an integrated part of the first portion 902 of the portable briefcase 900. The lower panel 940 is positioned generally along the lower edge of the back panel 910. The lower edge of a generally opaque collapsible left-side panel 930 is hingedly connected along the left edge of the lower panel 940. The lower edge of a generally opaque collapsible right-side panel 960 is hingedly connected along the right edge of the lower panel 940. The left side of the upper panel 920 is hingedly connected to the upper edge of the collapsible left-side panel 9.30. The right side of the upper panel 920 is hingedly connected to the upper edge of the right-side panel 960. The upper panel 920 can be lifted and the two collapsed side panels 930 and 960 can be unfolded.

Referring to Figure 9D, when the upper panel 920 is fully lifted, the left-side panel 930 and the right-side panel 960 can be straightened. The collapsible left-side panel 930 and the right-side panel 960 are then positioned generally perpendicular to the lower panel 940. The back panel 910 can be attached to the left edge of the collapsible left-side panel, the right edge of the collapsible right-side panel, and the lower edge of the upper panel by any connection means, including for example, those described above. A light-tight and collapsible chamber 980 is thus formed. A piece of retroreflective sheeting can be disposed within the chamber 980. In a particular embodiment, the piece of retroreflective sheeting can be attached to a leaflet 950. An open area 970 essentially parallel to and distanced from the back panel 910 can form an observation window, which permits an observer to view the retroreflective sheeting with the aid of a light source through the observation window.

When the chamber 980 is collapsed, the back panel 910 can be detached from the lower panel 940, the left-side panel 930, and the right-side panel 960; the upper panel 920 can be pushed toward the lower panel 940; the two collapsible side panels 930 and 960 can be collapsed along the folding lines 990, such that the upper panel 920 can be laid on top of a portion of the left-side panel 930 and a portion of the right-side panel 960; the back panel 910 can be folded onto the panel stack including the lower panel 940; optionally, the first portion 902 can be folded over to the second portion 904; and the portable briefcase 900 can then be closed.

Figure 10A illustrates another exemplary embodiment of a light-tight and collapsible chamber 1000 having more than one leaflet. In some embodiments, the light-tight and collapsible chamber 1000 may have a back panel 1005, a lower panel 1035, and a plurality of leaflets 1010, 1020, and 1030. In some implementations, at least a portion of each leaflet can be attached to the back panel 1005. In some other imlementations, each leaflet can be attached to the back panel 1005 along one edge of the leaflet and positioned at an angle from the back panel 1005. In some embodiments, each leaflet can support a piece of retroreflective sheeting by any attachment means. For example, at least a portion of a leaflet can be made from metal and the piece of retroreflective sheeting can include magnetic materials such that the leaflet can be attached to the piece of retroreflective sheeting by magnetic means.

Figure 10B illustrates another exemplary embodiment of a light-tight and collapsible chamber lOOOB. The light-tight and collapsible chamber 1000B includes a back panel 1040 and a lower panel 1060. In some implementations, the lower panel 1060 can be labeled with lines 1050 indicating pre-determined placement positions of leaflet. The lines 1050 can form a range of angles from the lower edge of the back panel 1040. The optical performance of viewing angles of retroreflective sheeting can be demonstrated by attaching a piece of retroreflective sheeting to a leaflet and positioning the leaflet along one of the lines 1050.

The present disclosure should not be considered limited to the particular examples and embodiments described above, as such embodiments are described in detail to facilitate explanation of various aspects of the invention. Rather the present disclosure should be understood to cover all aspects of the numerous inventions described herein, including various modifications, equivalent processes, and alternative configurations falling within the spirit and scope of the inventions.

Claims

What is claimed is:

1. A light-tight, collapsible chamber for use in demonstrating the optical performance of a piece of retroreflective sheeting placed within the chamber, comprising:

a generally opaque polygonal back panel having a plurality of edges;

a plurality of generally opaque side panels, wherein adjacent side panels are configured to attach to one another to form a light-tight connection, each of the plurality of opaque side panels attached along and positioned essentially perpendicular to one of the plurality of edges of the back panel to form a light-tight connection;

a leaflet attached to the back panel, wherein the leaflet is capable of attaching to a piece of retroreflective sheeting; and

an open area essentially parallel to and distanced from the back panel, the open area forming an observation window permitting an observer to view a piece of retroreflective sheeting positioned within the light-tight, collapsible chamber.

2. The light-tight, collapsible chamber of claim 1 , further comprising:

a light source positioned at a distance from the light-tight, collapsible chamber and capable of directing light onto a piece of retroreflective sheeting positioned within the light-tight, collapsible chamber.

3. The light-tight, collapsible chamber of claim 1 , wherein at least one of the plurality of generally opaque side panels is adapted to be detached from the back panel when the light-tight, collapsible chamber is disassembled.

4. The light-tight, collapsible chamber of claim 1, wherein the light-tight connection is formed by magnetic means, folding means, adhesive means, or fasteners.

5. The light-tight, collapsible chamber of claim 1 , wherein two of the plurality of generally opaque side panels are on opposite sides of a folding line.

6. The light-tight, collapsible chamber of claim 1 , wherein one of the plurality of generally opaque side panels has a folding line on the side panel, wherein the side panel is adapted to be folded along the folding line.

7. The light-tight, collapsible chamber of claim 1 , wherein the light-tight, collapsible chamber is adapted to be disassembled and stored in a briefcase.

8. The light-tight, collapsible chamber of claim 1 , wherein the leaflet is capable of being placed at an angle from the back panel.

9. The light-tight, collapsible chamber of claim 8, wherein the plurality of generally opaque side panels includes a lower panel providing a support surface for the light-tight, collapsible chamber, wherein the lower panel is labeled with a line indicating an angle from the lower edge of the back panel, and wherein the leaflet is adapted to be placed along the line.

10. A light-tight, collapsible chamber for use in demonstrating the optical performance of a piece of retroreflective sheeting placed within the chamber, comprising:

a generally opaque back panel including an upper edge, a lower edge, a left edge, and a right edge;

a generally opaque upper panel connected along and positioned generally perpendicular to the upper edge of the back panel;

a generally opaque lower panel connected along and positioned generally

perpendicular to the lower edge of the back panel;

two generally opaque side panels connected along and positioned generally perpendicular to one of the left edge and the right edge of the back panel respectively; and

an open area essentially parallel to and distanced from the back panel that forms an observation window permitting an observer to view the piece of retroreflective sheeting positioned within the light-tight, collapsible chamber;

wherein the upper panel is positioned essentially parallel to the lower panel;

wherein the two side panels are positioned essentially parallel to one another;

wherein the upper panel is connected to the two side panels and the lower panel is connected to the two side panels; wnerein the connections between the generally opaque panels provide a light-tight connection; and

wherein if the light-tight, collapsible chamber is collapsed, the two side panels are configured to be detached from the back panel and the upper panel and folded onto the lower panel, the upper panel is configured to be folded onto the back panel, and the back panel together with the upper panel is folded onto the lower panel.

1 1 . The light-tight, collapsible chamber of claim 10, further comprising:

a light source positioned at a distance from the light-tight, collapsible chamber and capable of directing light onto the piece of retroreflective sheeting positioned within the light- tight, collapsible chamber.

12. The light-tight, collapsible chamber of claim 10, wherein the light-tight connection is formed by magnetic means, folding means, adhesive means, or fasteners.

13. The light-tight, collapsible chamber of claim 10, further comprising:

a leaflet attached to the back panel along an edge of the leaflet, wherein the piece of retroreflective sheeting is configured to be attached to the leaflet.

14. The light-tight, collapsible chamber of claim 13, wherein the leaflet is configured to be placed at an angle from the back panel.

15. The light-tight, collapsible chamber of claim 10, wherein the light-tight, collapsible chamber is adapted to be collapsed and stored in a briefcase.

16. A light-tight, collapsible chamber for use in demonstrating the optical performance of a piece of retroreflective sheeting placed within the chamber, comprising:

a generally opaque lower panel connected along and positioned generally perpendicular to uit lu wci edge of the back panel;

two collapsible generally opaque side panels connected along and positioned generally perpendicular to one of the left edge and the right edge of the back panel, each of the two side panels having a folding line; and

wherein the upper panel is positioned essentially parallel to the lower panel and the two side panels are positioned essentially parallel to one another;

wherein the upper panel is connected to the two side panels, the lower panel is connected to the two side panels;

wherein the connections between the opaque panels provide a light-tight connection; and wherein if the light-tight, collapsible chamber is collapsed, the back panel is configured to be detached from the upper panel and the two side panels, the two side panels are configured to be folded along the folding line on the panel and folded onto the lower panel respectively, the upper panel is configured to be folded onto the two side panels, and the back panel is configured to be folded onto the upper panel.

17. The light-tight, collapsible chamber of claim 16, further comprising:

18. The light-tight, collapsible chamber of claim 16, wherein the light-tight connection is formed by magnetic means, folding means, adhesive means, or fasteners.

19. The light-tight, collapsible chamber of claim 16, further comprising:

a leaflet attached to the back panel along an edge of the leaflet, wherein the piece of retroreflective sheeting is configured to be attached to the piece of the leaflet.

20. The light-tight, collapsible chamber of claim 19, wherein the leaflet is configured to be placed at an angle from the back panel.

21. The light-tight, collapsible chamber of claim 16, wherein the light-tight, collapsible chamber is adapted to be collapsed and stored in a briefcase.