Abstract:
The present invention the present invention relates to methods and systems for performing security screening using trays and a cart to facilitate the management and flow of those trays.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation-in-part of U.S. patent application Ser. No. 11/070,094, filed Mar. 3, 2005 now U.S. Pat. No. 7,633,390, which is a continuation of U.S. patent application Ser. No. 10/611,430, filed Jul. 2, 2003, now issued as U.S. Pat. No. 6,888,460, which is related to and claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application Ser. No. 60/393,637 filed Jul. 3, 2002. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to systems and methods for the use of a cart in security screening. More specifically, the present invention relates to security screening using trays, and a cart to facilitate the management and flow of those trays. 
     BACKGROUND OF THE INVENTION 
     Security areas are typically encountered in places such as an airport security terminals, courthouse entrances and various other places where a person and their luggage or personal items may need to be searched prior to entering or leaving a particular room or area of a building. These security areas typically involve the steps of a person moving through a metal detector area and removing various items from their clothing, pockets or luggage and placing them in a separate area to be either hand checked or machine checked. It is common that people traveling through security areas, such as those in an airport security terminal, may be carrying electronic devices and in particular laptop/notebook-sized computers. These laptop computers are delicate devices which should not be dropped or jostled in an excessive amount as they can be damaged. It is very common that people traveling on business through airport security terminals will have such items sized like a laptop computer so that they can later do work on the plane. The person may have personal items such as wallets, keys, change, cell phones, PDAs and other small bags that need to be checked. These items are typically loose objects that can easily be lost or damaged if not handled in a safe manner. 
     After the person removes these items from their pockets they are usually placed into a tray or small container that is then either checked by the security personnel by hand or by a scanning device such as an x-ray machine, a particulate matter screener, or some other similar device as will be understood by a person of ordinary skill in the art. The trays that are typically used are non-standardized small trays. In addition, if the person has any electronic equipment such as a camera, a laptop computer or any other device with may have to be checked by the security personnel these items are sometimes put in a larger tray to be later hand checked by the security personnel or passed through a scanning device such as an x-ray machine, a particulate matter screener, or some other similar device as will be understood by a person of ordinary skill in the art. 
     A disadvantage to the present system used in security areas is that the trays for holding laptop computers are not part of a uniform system and do not protect the items from possible damage. Therefore, it is possible that multiple size trays that do not in any way correspond with one another may be used at a security area thus making storage of the trays when they are not in use cumbersome. A disadvantage to a non-standardized tray system is that when the trays are to be stored they may take up passenger access areas, thereby causing further waiting time as the security personnel moves the unused trays so that a person may pass through a passenger access area. Further it is common that there are inadequately-sized trays for holding large items such as laptop computers, thereby increasing the chance of the computers being damaged by being placed on a conveyer belt without being placed in a tray through a scanning device such as an x-ray machine, a particulate matter screener, or some other similar device as will be understood by a person of ordinary skill in the art. Also, the time taken to search for a possible adequately-sized tray creates inefficiency and extends the waiting time while a person is passing through a passenger access area. 
     Another disadvantage of the present system is that after the trays are used and the contents are emptied the tray must then be brought to a separate area of the security area. Currently, there is no system for transporting, storing and organizing the trays for easy access. Especially if there are large numbers and various sizes of trays, they may be cumbersome to transport and take up an excessive amount of space. Further, manually lifting and moving the trays can cause back and shoulder injuries, particularly when that action is repeated many times daily. 
     A disadvantage to the prior system is that the trays which are being used typically are plain trays and do not utilize space provided on the trays to generate additional revenue such as revenue which can be derived from advertising on the trays. 
     There exists a need for a system for a security area for moving the trays from a starting position to an ending position which allows the trays to be efficiently utilized, gathered and stored to be later used again. 
     There is also a need for a standardized sizing of the tray to allow for easier transport of the trays when they are not is use and also to provide a cleaner aesthetic appearance. 
     There is a need for uniformity from airport to airport to assist in the movement of people through the security checkpoints and also in the security process itself. 
     SUMMARY OF THE INVENTION 
     The present invention may eliminate the above-described disadvantages and provide for the above-described needs by teaching, for example, a system and device for use in securing a facility, and more particularly, by teaching a tray that may be used to contain various objects that are processed through a scanning device. The present invention may eliminate further disadvantages by teaching a cart that may be used in conjunction with one or more of such trays. 
     One embodiment of the present invention may be a system comprising a security scanning device through which objects may be passed, having a proximate end and a distal end, a plurality of trays, and a plurality of tray carts adapted to receive the trays, wherein the plurality of trays are provided in a first tray cart at the proximate end of the scanning device, and wherein the trays are adapted to be passed through the scanning device at the proximate end, and wherein the trays are received in a second tray cart after passing through the scanning device at the distal end of the scanning device, and wherein the second cart is adapted to be relocated to the proximate end of the scanning device. 
     A further embodiment of the present invention may be such a system wherein the scanning device comprises a device selected from the group consisting of a manual inspection station, an x-ray machine, a conveyor belt, and a particulate matter sensor. Another embodiment may be such a system wherein a plurality of the trays comprise nestable trays. A further embodiment may be such a system further comprising the step of substituting a third tray cart containing a plurality of trays for the first tray cart. Yet another embodiment may be such a system wherein the tray cart includes a roughly rectangular base having a bottom surface and a top surface, a plurality of wheels attached to the bottom surface, and a vertical positioning member attached to the top surface. Still another embodiment of the present invention may be such a system wherein the trays are adapted to display information such as advertising on an interior bottom surface of the trays. Yet an additional embodiment of the present invention may be such a system wherein the plurality of trays are adapted to display a unique tray identification number. 
     An embodiment of the present invention may be a method comprising positioning a first tray cart containing trays at the proximate end of a scanning device through which objects may be passed, wherein the scanning device includes a proximate end and a distal end, removing a tray from the first tray cart, passing the tray through the scanning device from the proximate end through to the distal end, providing a second tray cart at the distal end of the scanning device, and receiving the tray passed through the scanning device in the second tray cart. 
     A further embodiment of the present invention may be such a method wherein the scanning device comprises a device selected from the group consisting of a manual inspection station, an x-ray machine, a conveyor belt, and a particulate matter sensor. Another embodiment of the present invention may be such a method wherein a plurality of the trays comprise nestable trays. A further embodiment may be such a method wherein the nestable trays further comprise exposed sides capable of displaying information such as advertising. Yet another embodiment of the present invention may be such a method wherein one or more of the tray carts is adapted to permit substantial visual inspection of a plurality of trays placed thereon. 
     A further embodiment of the present invention may be such a method wherein the tray carts are adapted to be rollable. Another embodiment of the present invention may be such a method further comprising the step of repositioning the second tray cart from the distal end to the proximate end. A further embodiment of the present invention may be such a method wherein a plurality of the trays are adapted to receive an item selected from the group consisting of a laptop computer, a video camera, a camera, a purse, a coat, a pair shoes, and an umbrella. Yet another embodiment of the present invention may be such a method wherein a plurality of the trays are adapted to receive an item selected from the group consisting of a cell phone, a pager, a wallet, a set of keys, and a personal digital assistant. 
     A further embodiment of the present invention may be such a method wherein one or more of the tray carts comprises restraining walls that are substantially transparent. Another embodiment of the present invention may be such a method wherein one or more of the tray carts comprises a tray platform further including a resilient member. A further embodiment of the present invention may be such a method further comprising the step of providing a third tray cart. Yet another embodiment of the present invention may be such a method further comprising the step of substituting a third tray cart containing a plurality of trays for the first tray cart. Still another embodiment of the present invention may be such a method wherein the trays are adapted to display information such as advertising on an interior bottom surface of the trays. Yet an additional embodiment of the present invention may be such a method wherein the plurality of trays are adapted to display a unique tray identification number. 
     An embodiment of the present invention may be an apparatus for use as a tray cart for securing a facility including an approximately rectangular base comprising a bottom surface and a top surface, a plurality of wheels attached to the bottom surface of the base, and a vertical positioning member attached to the top surface of the base, wherein the vertical member includes at least one approximately C-shaped tubular member having a first end and a second end, wherein said first end and said second end are connected to said base. A further embodiment of the present invention may be such an apparatus wherein the apparatus is adapted to receive two differentially sized stacks of trays. 
     An embodiment of the present invention may comprise a tray for use in a security scanning system comprising a base having a first surface and a second surface, four containing walls extending approximately vertically from the base, shock absorbing material on the first surface of the base, and wherein the one or more of the walls displays a unique tray identification number. 
     In one embodiment, the present invention comprises a cart adapted for use in a security screening system comprising a lower base, a medial base positioned above and parallel to said lower base, an upper base positioned above and parallel to said lower and medial bases, two vertical distal members, and two vertical proximal members. In one embodiment, the vertical distal members and the vertical proximal members are arranged substantially perpendicular to the lower, medial, and upper bases. In another embodiment, each of the vertical distal and proximal members are joined to each of the lower, medial, and upper bases. 
     In one embodiment, each base of the cart comprises two longitudinal base members and two latitudinal base members. In another embodiment, the longitudinal base members are positioned substantially parallel to each other. In another embodiment, the latitudinal base members are positioned substantially parallel to each other. In yet another embodiment, the longitudinal base members are positioned substantially perpendicular to the latitudinal base members. In yet another embodiment, each end of each latitudinal base member is joined to an end of a longitudinal base member in about a ninety degree angle. 
     In one embodiment, the medial base further comprises a tray support shelf positioned above said rectangular base. In another embodiment, the cart further comprises two or more wheels. In yet another embodiment, the cart comprises two wheels and each of the wheels is joined to one of said vertical members. In another embodiment, any two of the vertical members extend beyond the upper base and terminate into a handle arranged perpendicular to the vertical members. 
     In one embodiment, the cart further comprises information displayed on said cart. In another embodiment, the information is advertising. In yet another embodiment, the cart comprises non-metallic materials. In one embodiment, the cart comprises polyvinyl chloride. 
     Another embodiment of the present invention provides for a method comprising using the cart as described above. 
     Another embodiment of the present invention provides for a method comprising using a plurality of carts in a security screening system, wherein said security screening system comprises a security scanning device having a proximal end and a distal end, and one or more trays comprising a base having upwardly extending walls and advertising visible to a user of said tray, wherein said trays are initially contained in a first cart positioned at said proximal end of said security scanning device, wherein said trays are passed through said security scanning device from said proximal end to said distal end, wherein said trays are finally contained a second cart at said distal end of said security scanning device, and wherein said second cart is moved to the proximal end of said security scanning device. 
     Another embodiment of the present invention provides for such a method, wherein the trays further comprise a tray identification number. 
     Another embodiment of the present invention provides for such a method, wherein said advertising is attached to each of said trays using a method selected from the group consisting of being printed upon said tray, being molded directly into said tray, and being attached to said tray using an adhesive substance. Yet another embodiment of the present invention provides for such a method, wherein said carts further comprise information displayed on said carts. Yet another embodiment of the present invention provides for such a method, wherein said information is advertising. 
     Another embodiment of the present invention provides for such a method, wherein each of said trays and carts comprises non-metallic materials. 
     These and other features of the invention may be more fully understood by reference to the following drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side elevation view of a specific embodiment of the tray of the present invention. 
         FIG. 2  is a top plan view of a specific embodiment of the tray of the present invention. 
         FIG. 3  is a cross-sectional view taken along line A-A specific embodiment of the tray of the present invention as shown in  FIG. 2 . 
         FIG. 4  is a side elevational view of a specific embodiment of the tray of the present invention. 
         FIG. 5  is a cross-sectional view showing a specific embodiment of the tray of the present invention in a nesting position. 
         FIG. 6  is a side elevational view of another specific embodiment of the tray of the present invention. 
         FIG. 7  is a top plan view of yet another specific embodiment of the tray of the present invention. 
         FIG. 8  is a top plan view of yet another specific embodiment of the tray of the present invention. 
         FIG. 9  is a side elevational view of a specific embodiment of the cart of the present invention. 
         FIG. 10  is a schematic of a specific embodiment of the system of the present invention. 
         FIG. 11  is a top plan view of yet another specific embodiment of the tray of the present invention. 
         FIG. 12  is a front elevational view of a specific embodiment of the tray of the present invention (a rear view of this embodiment may be a mirror image of the front elevational view). 
         FIG. 13  is a top perspective view of a specific embodiment of the tray of the present invention. 
         FIG. 14  is a left side elevational view of a specific embodiment of the tray of the present invention (a right side view of this embodiment may be a mirror image of the left side elevational view). 
         FIG. 15  is a top plan view of yet another specific embodiment of the tray of the present invention. 
         FIG. 16  is a front elevational view of a specific embodiment of the tray of the present invention (a rear view of this embodiment may be a mirror image of the front elevational view). 
         FIG. 17  is a top perspective view of a specific embodiment of the tray of the present invention. 
         FIG. 18  is a left side elevational view of a specific embodiment of the tray of the present invention (a right side view of this embodiment may be a mirror image of the left side elevational view). 
         FIG. 19  is a portion of a cross-sectional view of a specific embodiment of the tray of the present invention. 
         FIG. 20  is a side perspective view of a specific embodiment of the cart of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     It is to be understood that the present invention is not limited to the particular methodology, compounds, materials, manufacturing techniques, uses, and applications described herein, as these may vary. It is also to be understood that the terminology used herein is used for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention. It must be noted that as used herein and in the appended claims, the singular forms “a,” “an,” and “the” include the plural reference unless the context clearly dictates otherwise. Thus, for example, a reference to “a tray” is a reference to one or more tray and includes equivalents thereof known to those skilled in the art. Similarly, for another example, a reference to “a step” or “a means” is a reference to one or more steps or means and may include sub-steps and subservient means. All conjunctions used are to be understood in the most inclusive sense possible. Thus, the word “or” should be understood as having the definition of a logical “or” rather than that of a logical “exclusive or” unless the context clearly necessitates otherwise. Structures described herein are to be understood also to refer to functional equivalents of such structures. Language that may be construed to express approximation should be so understood unless the context clearly dictates otherwise. 
     Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. Preferred methods, techniques, devices, and materials are described, although any methods, techniques, devices, or materials similar or equivalent to those described herein may be used in the practice or testing of the present invention. Structures described herein are to be understood also to refer to functional equivalents of such structures. All references cited herein are incorporated by reference herein in their entirety. 
     In specific embodiments, the present invention provides a tray and a system that can be used in security areas to provide efficient movement of loose items, laptop computers and electronic equipment from a starting point to an ending point. Specifically, the present invention, in specific embodiments, may be used in an area such as an airport security checkpoint that may have a metal detector present that a person has to walk through. As the person walks through the security checkpoint they may have to remove such items such as wallets, keys, change and other small objects which are placed into a tray which is either then hand checked or placed through a scanning device separate from the metal detector. At the same time, if a person has an item such as a laptop computer or electronic equipment such as a video camera or digital camera, they are instructed to place such items into a larger size tray which is then passed through a scanning device and/or hand checked. 
     In specific embodiments, the present invention allows for a system comprising one uniform size of the trays in which items are to be placed so that the trays may easily be stacked and transported after they are used. The trays may also comprise specified areas to allow for information such as advertising materials to be attached. These advertising materials may be changed as often as necessary so that different companies&#39; advertisements can be represented on the trays without the need for manufacturing new trays. 
     In a specific embodiment the informational materials can be permanently attached to the trays. In specific embodiments, the trays may comprise a durable type that need not be replaced unless lost or considerably worn. In specific embodiments, the trays may comprise a disposable type that may be replaced after the informational material becomes outdated or worn and a new tray is made. 
     In a specific embodiment, the present invention may comprise two or more different sizes of trays. For example, a larger size tray can be used to hold larger items such as cameras, laptop computers or purses and a smaller size tray can be used when items such as keys, wallets, cell phones, PDAs and watches are to be removed and placed in a tray for inspection. 
     In specific embodiments, the present invention may comprise a system for facilitating the use and transfer of the trays of the present invention from the starting point in the security checkpoint to the ending point in the security checkpoint. In specific embodiments, the system comprises a first tray or cart that holds several empty trays in a organized stacked manner so that a tray can be removed when needed. The tray is then used by the user and passes through the security checkpoint. After the contents are taken out of the tray the empty tray is then inserted into a second cart that is identical to the first cart. The trays are then stacked in the second cart so that the empty trays are conveniently stored for later use. After the second cart is completely filled with empty trays the second cart can be moved to the position of the first cart, and the empty trays are ready to be used again as needed. 
     The present invention provides a cost effective way of providing security trays for a security checkpoint while at the same time generating revenue from the advertising that is contained thereon. Further, the present system provides an efficient system for moving the trays for use and removal after they are used. 
     Security checkpoints are both a time consuming and frustrating part of traveling for frequent fliers and vacationers alike. The present invention provides a system of speeding up the process of processing people through these checkpoints to decrease the likelihood of delays for travelers. The present invention also has the advantage of increasing passenger flow through checkpoints and increasing traveler satisfaction due to the lack of delays. 
     Referring to  FIG. 1 , the side elevation view of a specific embodiment of the tray of the present invention is shown. The tray  10  may comprise a base  12  having upwardly extending walls  14  extending therefrom. In one specific embodiment, base  12  may comprise a rectangular or square shape. In specific embodiments, base  12  may comprise a non-slip bottom, such as to allow the tray to more effectively travel on conveyor belts. In one specific embodiment, the bottom of base  12  may comprise rubber strips that act to prevent slippage. Referring to  FIG. 2 , tray  10  may comprise a first wall  16  and a second wall  18  positioned substantially parallel to the first wall. The first wall  16  and second wall  18  may be connected to each other by a substantially perpendicular third wall  20  and a fourth wall  22  parallel to the third wall  20 . Referring to  FIG. 1 , in specific embodiments, the walls  14  terminate at an upper lip  46 . 
     Referring to  FIG. 2 , in specific embodiments, tray  10  may comprise a handle  30  so that the tray can be easily moved by the user. In one specific embodiment, handle  30  may be an extended portion attached adjacent the first wall  16  and second wall  18 . The tray may comprise plastic made by injection molding, PVC made by stamping out, or any other appropriate material as will be understood by a person of ordinary skill in the art. In specific embodiments, the tray may comprise clear or translucent plastic so that the contents in the tray can always be seen by the security personnel. However, any rigid material can be used to make the tray. In specific embodiments, the entirety of tray  10  may be constructed from non-metallic materials, to ensure that tray  10  will not set off a metal detector. In other embodiments, tray  10  may be advantageously constructed of a material that is designed not to give off false positives when being used in the screening process. 
     Indeed, commercially available trays can be used in certain embodiments of the invention. Specifically, Rubbermaid® (Atlanta, Ga.) model number RCP 3349 may be used, as may Tablecraft® (Gurnee, Ill.) model number 1529, Sterilite® (Townsend, Mass.) model numbers 1954 or 1956, or any other commercially available or custom designed tray of similar function. 
     Referring to  FIG. 1 , in one specific embodiment the base  12  may comprise a top surface  24  and a bottom surface  26 . In specific embodiments, there may be a cavity between top surface  24  and bottom surface  26 . In specific embodiments, the top surface  24  may comprise a transparent or translucent material. In one such an embodiment, either top surface  24  or bottom surface  26  may be temporarily removed to allow information such as advertising to be placed within the cavity between top surface  24  and bottom surface  26 . For example and not to limit the present invention, top surface  24  or bottom surface  26  could be temporarily removed by further comprising a hinge to allow that surface to swing open, or by being able to be slid out. 
     Referring to  FIG. 3 , the top surface  24  of base  12  may be ribbed or flat, and may comprise a padding material  28  positioned thereon so that any objects placed with the tray  10  are cushioned by the padding  28 . In specific embodiments, padding  28  may comprise a rubber or neoprene type material to absorb any shock that the objects inside may experience when moving the tray  10 . However, it is envisioned that, in certain embodiments, any material which cushions and absorbs vibration can be used. The bottom surface  26  of the base  12  may, in some embodiments, comprise a non-marking material  29  placed thereon so that the tray  10  does not scratch or damage any surface which the tray  10  is placed upon. It is envisioned that, in certain embodiments, both the top padding  28  and bottom padding  29  can be attached by using an adhesive, Velcro® (Manchester, N.H.), or any other means provided that the padding is securely attached to the tray  10 . In another specific embodiment, informational material  41  can be placed upon either the top surface  24  or on top of the padding  28 . In other embodiments, the informational material  41  can be held on by the use of a semi-permanent adhesive, clips or a Velcro® (Manchester, N.H.) type attachment. Informational material  41  may comprise printed materials such as, without limitation, written text, a picture, or a combination of the two. In other embodiments, informational material  41  may comprise a three dimensional holographic image, or a lenticular image. In specific embodiments, informational material  41  may comprise advertising material such as, without limitation, an ad for a product or service. In other embodiments, informational material  41  may comprise public service announcements. 
     Referring to  FIG. 3 , in a specific embodiment, the informational material  41  can be permanently attached to the top of the padding  28 . The informational material  41  can be permanently imprinted on the padding  28  or (referring to  FIG. 1 ) on the top surface  24  if a padding  28  is not used. It is envisioned that the informational material  41  can be permanently attached using either a permanent adhesive or another method of imparting a printing on the material such as sublimation or silk-screening. Referring to  FIG. 3 , it is also envisioned that the informational material  41  itself could be molded into the padding  28  or (referring to  FIG. 1 ) the top surface  24  of the base  12 . 
     Referring to  FIG. 2 , in specific embodiments, the tray  10  may also comprise an identification number  13  which may be used to ensure that a tray whose contents have been identified as a security threat is subjected to further scrutiny. For example, and not to limit the invention, if security personnel, in examining the contents of a tray  10  using a scanning device, find a possible security threat in that tray  10 , the security personnel can then use the identification number  13  to ensure that that tray  10  is examined more thoroughly. As each tray will have a unique identifier associated with it, the identification number  13  can make certain that any given tray  10  is not mistaken for another tray  10 , and thus erroneously subjected to or not subjected to further screening procedures. As a further result of this advantageous aspect, the present invention can prevent very costly and inconvenient terminal clearings. 
     Further, identification number  13  may be used to associate a given tray with a given person. For example, but not to limit the invention, once a security threat has been identified in a tray  10 , the security personnel can then identify whose belongings are in the tray using verbal means, by looking at video footage, or through some other way. After such identification has occurred, the owner of the contents of that tray  10  can be detained while their belongings are subjected to further screening procedures. 
     Alternatively, in specific embodiments, when a person places their belongings into a tray  10 , they could be told the identification number  13  of that tray  10 , or perhaps given a slip of paper with that identification number  13  on it. In such a manner, each person who places belongings in a tray  10  would be automatically associated with that tray  10 . Thus, if the contents of a given tray are determined to be a security threat, the owner of those contents can be easily identified. 
     In one specific embodiment the identification number  13  may be located on one of the (referring to  FIG. 1 ) upstanding walls  14 . However, in certain embodiments of the invention, (referring to  FIG. 2 ) the number  13  can be located anywhere that is visible on the tray  10 . 
     In specific embodiments of the invention, identification number  13  may comprise an x-ray readable, or radiopaque number. In such embodiments, identification number  13  need not be visible on the tray  10 , though it may be. In such embodiments, identification number  13  may be embedded somewhere within the tray  10 , such as within base  12  or one of the walls  14 , as shown in  FIG. 19 . In specific embodiments, identification number  13  may comprise a number that can be seen by using a scanning device. Thus, identification number  13  may be visible to the person operating the scanning device, even if it is not visible to the naked eye. 
     In other specific embodiments, identification number  13  may comprise a barcode. Said barcode may be machine-readable, and may be a linear barcode, a stacked barcode, a 2D barcode, or any other type of barcode as understood by one of ordinary skill in the art. In other specific embodiments, identification number  13  may comprise a radio frequency identifier, or RFID. Such RFID may be active or passive, and may be located on, attached to, embedded within, or otherwise associated with tray  10 . 
     In specific embodiments, identification number  13  may comprise a combination of the above possible identification numbers  13 . For example, tray  10  may comprise a visible identification number  13  and an x-ray readable identification number  13 . Alternatively, tray  10  may comprise an x-ray readable identification number  13  and an RFID identification number  13 . 
     In specific embodiments, tray  10  may also comprise a sensor that detects substances such as, without limitation, trace materials of explosives. Such a sensor could be used in conjunction with a RFID device to notify the screening personnel if trace materials were detected. Alternatively, the sensor could be linked to some other notification device such as, without limitation, a light emitting diode (LED). 
     In specific embodiments, tray  10  may also comprise an x-ray readable, or radio opaque, calibrated reference point  191 , as shown in  FIG. 19 . In one specific embodiment, such a reference point  191  may be used to determine the approximate size of a given object within the tray  10 . For example, but not to limit the invention, reference point  191  may comprise a four inch by one inch radio opaque rectangle, which would allow someone operating a scanning device to readily determine if an object located within a given tray  10  was over 4 inches long. In specific embodiments, such a reference point  191  could comprise any length or shape that would be helpful as a reference for operators of a scanning device. Further, in specific embodiments, a tray  10  may comprise more than one reference point  191 , perhaps one aligned vertically and another aligned horizontally. In specific embodiments, the reference point  191  may be placed near the edge of tray  10 , such that it will not be confused with or obfuscate the view of the contents of the tray  10 . In specific embodiments, the reference point  191  may comprise a reference point that can be seen by using a scanning device. Thus, the reference point  191  may be visible to the person operating the scanning device, even if it is not visible to the naked eye. 
     Referring to  FIG. 1 , in one specific embodiment, tray  10  may comprise an interior support post  43  positioned at each corner between each of the individual upstanding walls  14  is (referring to  FIG. 2 ). These support posts  43  are positioned, in some embodiments, adjacent the intersection of each wall and extend upwardly from the base  12 . These posts  43  are used so that when multiple trays  10  are stacked inside one another the base  12  of a second tray  10  placed inside of a first tray  10  will rest upon the support posts  43  and not on the top surface  24  of the base  12 . An advantage to this design is that the trays  10  will not become wedged between one another but instead are separated from one another by the height of the support posts  43  to allow the trays  10  to be easily separated. A further advantage to these support posts  43  is that since the support post  43  is connected to the base  12  and the walls  14  in which they attach, they provide additional strength and support to the walls  14  and the joints created at their intersections. 
     In specific embodiments, tray  10  may further comprise informational material  42 , which may comprise printed materials such as, without limitation, written text, a picture, or a combination of the two. In other embodiments, informational material  42  may comprise a three dimensional holographic image, or a lenticular image. In specific embodiments, informational material  42  may comprise advertising material such as, without limitation, an ad for a product or service. In other embodiments, informational material  42  may comprise public service announcements. In specific embodiments, tray  10  may also comprise an information dispenser, which may allow users of the tray to take information with them, such as a coupon or informational pamphlet. 
     Referring to  FIG. 2  it is envisioned that, in specific embodiments, the first wall  16 , second wall  18 , third wall  20  and fourth wall  22  can each comprise (referring to  FIG. 1 ) a window  36  on the outer surface  32  opposite the inner surface  34  of each wall. The window  36  may be used so that informational material  42  can be placed within the window  36  so that people using the tray  10  and the people passing through the security checkpoint will be able to see the information  42 . In one specific embodiment, the window  36  can be formed on the outer surface  32  of each of the walls  14 , however, for exemplary purposes and not to limit the present invention, the structure of the window  36  on the third wall  20  will be described in detail with the remaining walls having the same structure. In specific embodiment, informational material  42  may comprise a three dimensional holographic image, or a lenticular image. 
     In specific embodiments, the window  36  may comprise an inner recess  40  that is created by the outer surface  32  of the first wall  16  and an outer cover  38  that is attached over the outer surface  32  of first wall  16 . The outer cover  38  may comprise a transparent or translucent material depending on the user&#39;s needs. It is envisioned that a portion of the peripheral edge of the window  36  may be either adhesively attached to, or molded into, the outer surface  32  of the first wall  16 . However, an open portion  31  may be allowed to remain so that informational material  42  can be placed in the recess  40 . Between the outer surface  32  and the outer cover  38  the inner recess  40  is formed which is sized to allow information  42  to be placed within the inner recess  40 . The informational material  42  can be made of a thin paper-like material or any other material such as a plastic or metal provided that it fits within the inner recess  40 . In specific embodiments, the informational material  42  may be of flat configuration and may comprise an outer surface having printing thereon with this side being positioned adjacent the outer cover  38  so that it can be seen through the transparent or translucent outer cover  38 . It is envisioned that a seal  43  can be placed above the inner recess  40  to close off the space between the outer cover  38  and the outer surface  32  to prevent the informational material  42  from falling out of the inner recess  40 . In specific embodiments, the seal  43  may comprise a hinged type construction that allows the seal  43  to be selectively moved to either prevent or allow material to be removed from the inner recess  40 . In specific embodiments, the seal  43  may comprise a removable friction type material such that it can be removed when needed but does not easily fall out of the recess  40 . In specific embodiments, the seal  43  may comprise a tape-like seal that is removable. In certain specific embodiments, seal  43  may comprise a seal that is disposable. 
     An advantage of certain embodiments of the present invention is that various informational materials  42  can be easily interchanged in the windows  36  when needed because the informational materials  42  are not permanent. 
     In a specific embodiment, the informational material  42  can be permanently attached, temporarily attached, imprinted upon, molded into, or otherwise associated with any of the walls of the tray. It is envisioned that the informational material  42  can be permanently attached to (referring to  FIG. 2 ) base  12 , first wall  16 , second wall  18 , third wall  20  or fourth wall  22 . In another embodiment, the informational material  42  may be attached, temporarily attached, imprinted upon, molded into, or otherwise associated with any surface on tray  10 . In a specific embodiment, the informational material  42  may be created separately from tray  10  and attached to the surface of tray  10  using an adhesive of a permanent or temporary nature. In a specific embodiment, the informational material  42  may be created separately from tray  10  and placed inside of tray  10  along the top surface  24  of base  12 . 
     Referring to  FIG. 1 , the informational material  42  can be permanently attached to tray  10  so that inadvertent removal of the informational material  42  can be prevented. It is envisioned that the informational material  42  can be silk-screened or imprinted on the outer surface of the tray  10 . After the tray  10  has been used, and if the informational material  42  has been worn partially away, the tray  10  can be disposed of and a new tray  10  can be created having either the same information or different information. 
     An advantage to the specific embodiment of a permanent informational material  42  being attached to the tray  10  is that new trays  10  are constantly being made as the older trays  10  are either used or worn. These trays  10  can be of a disposable variety and can be recycled after they are no longer used. Another advantage to the alternative embodiment of the present invention is that the recycling of trays  10  constantly provides a clean and uniform look to all checkpoint areas since the trays  10  that are being used are in good condition. In specific embodiments, tray  10  may be constructed from recyclable materials. 
       FIGS. 3 and 4  show how, in specific embodiments, the first wall  16  and second wall  18  may comprise an indentation  54  formed in each wall. First wall  16  and second wall  18  may comprise a first section  48  which extends upward from the base  12 , a second section  50  which is substantially perpendicular to the first section  48  at a first end  49  connected to a third section  52  at a second end  51  with the third section  52  being substantially perpendicular to the second section  50  and in a parallel plane to the first section  48 . The first wall  16  and second wall  18  may comprise these three sections so that the trays can be easily stacked within one another. The horizontal second section  50  and the first section  48  may form the actual indentation  54  itself. 
       FIG. 5  shows how the trays  10 , in specific embodiments, may be nested within one another and how the third section  52  may terminate at an upper lip  46 . The upper lip  46  of the third section  52  contacts the second section  50  of a second tray  53  when a first tray  10  and second tray  53  are placed within one another. 
     An advantage of the nesting system in these specific embodiments is that when the trays are not being used, they can be easily be stacked for storage and used at a later time. A further advantage of the nesting system is that since the informational materials  42  may be on the outer surface of the tray the informational materials  42  can be seen at all times thereby increasing the visibility of the informational materials  42  to potential consumers which are the people being processed through the security checkpoint. 
     Another specific embodiment of the present invention, tray  60 , is shown in  FIG. 6 . Tray  60  may comprise a smaller tray for items such as, without limitation, keys, change, cell phones, PDAs and wallets. Tray  60  may comprise base  62  having upstanding walls  64 . The upstanding walls  64  may terminate at a second part  66 , which is preferably perpendicular to the upstanding walls  64 . The second part  66  may comprise first end  61 , which is connected to the upstanding walls  64  and extends away from the upstanding wall  64  to a second end  63  which is connected to an extension  68 . The extension  68  may extend toward the base  62  either partially or completely to the base  62 . The extension  68  is sized to allow for a window  67  to be placed thereon. The construction of the window  67  is similar to the window  36  used in the first tray  10 , except that it may be smaller in construction to fit on tray  60 . Referring to  FIG. 7  a top plan view of tray  60  is shown. Tray  60  may comprise an aperture  70 , which may be used as a grip portion on the second part  66  to allow a user to place their fingers within these holes to securely grip the tray  60 . An identification number  69  that is unique to each tray  60  can be located on the second part  66  so that the tray  60  can later be identified as being used by a particular person. 
     Another specific embodiment of the present invention, tray  80 , is shown in  FIG. 8 . Tray  80  may comprise the same general shape and construction as tray  60 . The difference between tray  60  and tray  80  is that several apertures  90  are positioned on a second part  86  at each of the four corners of the tray  80 . An advantage to this design is that a user can securely grip the tray  80  using any of these apertures  90  to move the tray  80  to the desired area. It is envisioned that this tray  80  may comprise on its side wall  81 , for example, a similar window  36  as in tray  10 , therefore, it will not be described in detail. 
     Referring to  FIG. 10 , a specific embodiment of a system  100  of the present invention is shown. In specific embodiments, the system  100  may comprise using the trays  10 ,  60 ,  80  described earlier. The system of the present invention comprises using a first cart  102  at a starting point before the security point  104 , using trays  106  and  108 , and the using of a second cart  110  which is identical to the first cart  102 . Alternatively, only one uniform size of tray could be used, or three or more sizes of trays could be used. While the system will be explained as using two tray sizes, it is understood that it could be carried out with one tray size, or with three or more tray sizes. If the system was carried out with only one tray size, the carts need only be adapted to deal with that one tray size. If the system was carried out with three or more tray sizes, the carts should be adapted to deal with those three or more tray sizes. As a person enters the checkpoint, they are told by security personnel to put any of their carry on baggage or electronic items, such as, without limitation, laptop computers, onto the conveyer belt to be processed through the scanning device. With the present invention, a laptop computer or some other item may be placed by the person being searched into a larger tray  108 , which is sized to fit around the laptop computer so that it is not damaged as it is passing over the conveyer belt and through the scanning device. The person is then usually asked by security personnel to remove any loose items and bags and place them in either a smaller tray  106  or a larger tray  108  as previously described depending on the size of the items which are to be searched. A first cart  102  is placed prior to the security point where the user is then asked to remove such items. The first cart  102  is constructed so that it holds the trays  106  and  108  in a stacked position so that the empty trays can easily be taken out of the cart  102  and given to the person. After the person has put the various items into the trays  106 ,  108 , the trays  106  and  108  are given back to the security personnel, who then searches the items in the trays  106  and  108 . The user then proceeds through the security point  104 . Typically in an airport or other area the user will be through the security point  104  and then, at a later time, receive the trays  106  and  108  which they placed their items into prior to passing through the security point  104  and be told to take their items out of the trays  106  and  108  and proceed out of the security area. After the person has removed their items from the trays  106  and/or  108 , the trays  106  and/or  108  can be placed in a second cart  110  which is identical to the first cart  102 . The empty trays  106  and  108  are stacked in a specific area of the cart  110  so that the trays can later be used again. 
     In specific embodiments, after the second cart  110  is completely filed with empty trays  106  and  108 , the second cart  110  can be moved, by being pushed, pulled, or otherwise propelled, to the position of the first cart  102  prior to the security point  104  and provide empty trays for people going through the security point  104 . After the first cart  102  is depleted of trays  106  and  108  the first cart  102  can be moved, by being pushed, pulled, or otherwise propelled, to the location of the second cart  110  to then receive empty trays  106 ,  108  at the end of the security point  104 . The use of cart  110  to move the trays  106 ,  108  may advantageously prevent back and shoulder injuries incurred by manually lifting and moving the trays  106 ,  108 . The rotation of the security carts  102  and  110  and the trays  106  and  108  creates an efficient and convenient way to transport the trays from the beginning to the end of the security point  104 . In specific embodiments, the system  100  may be used with any appropriate cart, and may be used with only one tray (tray  106 , tray  108 , or some other appropriate tray) as opposed to using both trays  106  and  108 . 
     It is envisioned that, in specific embodiments, a third cart  103  can be used in addition to the first cart  102  and the second cart  110 . The third cart  103  can be used as a back up or spare cart with empty trays  106  and  108  contained within it to be placed in the position of the first cart  102  when needed to further speed up the process of providing trays to people going through the security checkpoint. In one embodiment, the security checkpoint may be configured where the passengers are moved through the checkpoint automatically, e.g., by conveyor or moving walkway. The third cart  103  can also be used in addition to the second cart  110  as an area to place the empty trays  106  and  108  after they are used. The use of the third cart  103  further facilitates the flow of the trays  106  and  108  from the beginning to the end of the security checkpoint during times when peak travel and passenger volume is experienced at an airport security checkpoint. In specific embodiments, four or more carts may be used to further facilitate efficient and easy handling of the trays  106 ,  108  and maintain a high passenger flow through the security checkpoint. For example, two carts with trays may be provided at the beginning of the security checkpoint, and two empty carts may be provided at the end of the checkpoint, to provide for higher tray and passenger throughput. 
     Referring to  FIG. 9 , a specific embodiment of the cart of the present invention, cart  102 , which is adapted to hold two tray sizes, will be described in detail. The first cart  102  may comprise base  122 . Base  122  may have, in specific embodiments, wheels  124  attached to the bottom surface thereon. In one specific embodiment the base  122  may comprise a rectangular or square shape with the wheels  124  placed at each corner of the base  122 . The base  122  may comprise several walls  132  extending upwardly from the base  122  opposite the wheels  124 . In a specific embodiment, the walls  132  may comprise a clear plastic or a metal material such as steel for durability, however, it is envisioned that plastic or any other rigid material can be used, as understood by one of ordinary skill in the art. The walls  132  may be spaced apart from each other to form a first tray recess  126  and a second tray recess  127 . The first tray recess  126  is used for holding the smaller trays  106  and the second tray recess  127  is used for holding the larger trays  108 . Each of the recesses are constructed so that the trays  106  and  108  can be placed within the recesses so that they do not fall out of the cart  102  and can be transported. In one specific embodiment, both tray recesses  126  and  127  have platforms  128  at the lower end thereof adjacent the base  122 . The tray platforms  128  may be supported by resilient members  130  that are attached to both the base  122  and the tray platforms  128 . The resilient members  130  may comprise metal springs or any other resilient material such as plastic or rubber. The tray platforms  128  and the resilient members  130  may be used to support the trays  106  and  108  that are placed within the tray recesses  126  and  127 . It is envisioned that in a specific embodiment tray platform  128  may not comprise resilient members  130  and that the trays  106  and  108  themselves will rest upon the platform  128 . In another specific embodiment, the walls  132  of the cart  102  are divided into a first wall  134  and a second wall  136  that forms tray recess  126 . The recess creates a vertical column that allows the trays to be easily inserted into and taken out of the top of the cart  102  when needed thus providing a convenient and organized way of stacking the trays  106  and  108  in the cart  102 . The second wall  136  and a third wall  138  form the second tray recess  127 . The second tray recess  127  is similar to the first tray recess  126  except that the spacing between the second wall  136  and the third wall  138  is different than the spacing between the first wall  134  and second wall  136  to allow the differently sized trays to fit within the second recess  127 . 
     In specific embodiments, the cart need only be adapted to hold one tray size. In these embodiments, cart  201 , shown in  FIG. 20 , may be used. In specific embodiments, cart  201  may comprise two wheels  202 , positioned at the distal end of the cart. Cart  201  may also comprise two stoppers  203 , positioned at the proximal end of the cart. In this manner, cart  201  may be rolled from place to place by tilting the cart  201  such that its weight rests solely on wheels  202 . However, when cart  201  is positioned on wheels  202  and stoppers  203 , it is advantageously stable. Alternatively, cart  201  may comprise some device other than wheels to facilitate movement, such as, without limitation, runners or a hovering device, which may be non-metallic. Alternatively, cart  201  may be simply slid on its structure, moved with a separate carrier or dolly with wheels, carried by personnel, moved along a conveyor belt, or moved in some other manner. 
     In specific embodiments, cart  201  may comprise a lower base, which may comprise two longitudinal lower base members  204  and two latitudinal lower base members  205 . The longitudinal lower base members  204  may be positioned substantially parallel to each other and substantially perpendicular to the latitudinal lower base members  205 , which are also parallel. Each end of each latitudinal lower base member  205  may be joined to an end of a longitudinal lower base member  204 . In one embodiment, the ends may be joined in about a ninety degree angle, creating a rectangular lower base. Wheels  202  may be joined to the distal latitudinal lower base member  205  to provide the advantages described above, though wheels  202  may be joined to any of the lower base members  204 ,  205 . 
     In specific embodiments, cart  201  may comprise a medial base, which may comprise two longitudinal medial base members  210 , two latitudinal medial base members  212 , and a cross support medial base member  211 . The longitudinal medial base members  210  may be positioned substantially parallel to each other and substantially perpendicular to the latitudinal medial base members  212 , which may also be parallel. Each end of each latitudinal medial base member  212  may be joined to an end of a longitudinal medial base member  210 . In one embodiment, the ends may be joined in about a ninety degree angle, creating a rectangular medial base. Cross support medial base member  211  may be positioned to bisect each longitudinal medial base member  210  in a substantially perpendicular fashion, thus dividing the rectangular medial base into two equal sized, smaller rectangles. In specific embodiments, tray support member  215  may be positioned above medial base members  210 ,  211 ,  212  to create a shelf. Tray support member  215  may be joined to the medial base members  210 ,  211 ,  212 , or it may simply lie across them. In specific embodiments, the medial base of cart  201 , with or without tray support member  215 , may be used to support the bottom of a tray  10 , which may or may not have other trays  10  stacked on top of it. 
     In specific embodiments, cart  201  may comprise an upper base, which may comprise two longitudinal upper base members  213  and two latitudinal upper base members  214 . The longitudinal upper base members  213  may be positioned substantially parallel to each other and substantially perpendicular to the latitudinal upper base members  214 , which are also parallel. Each end of each latitudinal upper base member  214  may be joined to an end of a longitudinal upper base member  213 . In one embodiment, the ends may be joined in about a ninety degree angle, creating a rectangular upper base. In specific embodiments, the upper base of cart  201 , may be used to support the sides of a tray  10 , which may or may not have other trays  10  stacked on top of it, to keep that tray  10  from falling off of the medial base. 
     In specific embodiments, the lower, medial, and upper bases of cart  201  may be joined at the proximal end by vertical proximal members  206 . Vertical proximal members  206  may be positioned substantially parallel to each other and substantially perpendicular to each of the base members  204 ,  205 ,  210 ,  211 ,  212 ,  213 ,  214 . In this manner, the proximal side of cart  201  may resemble a ladder, with the latitudinal base members forming the “ladder” rungs. Further, in specific embodiments, each of the stoppers  203  may be positioned at the bottom of each of the vertical proximal members  206 . 
     In specific embodiments, the lower, and medial bases of cart  201  may be joined at the distal end by lower vertical distal members  207 . Lower vertical distal members  207  may be positioned substantially parallel to each other and substantially perpendicular to each of the base members  204 ,  205 ,  210 ,  211 ,  212 . In specific embodiments, the medial and upper bases of cart  201  may be joined at the distal end by upper vertical distal members  208 . Upper vertical distal members  208  may be positioned substantially parallel to each other and substantially perpendicular to each of the base members  210 ,  211 ,  212 ,  213 ,  214 . In this manner, the distal side of cart  201  may resemble a ladder, with the latitudinal base members forming the “ladder” rungs. In an alternative embodiment, lower vertical distal members  207  and upper vertical distal members  208  may be continuous vertical distal members. 
     Further, in specific embodiment, wheels  202  may be attached to lower vertical distal members  207  as opposed to one of the lower base members. Upper vertical distal members  208  may also, in specific embodiments, extend past the upper base and eventually be joined with handle  209 , which may be positioned substantially perpendicular to upper vertical distal members  208 . 
     In specific embodiments, cart  201  may comprise one or more information areas, shown in  FIG. 20  as information areas  216 ,  217 . Information areas  216 ,  217  may comprise fabric or some other material stretched between two parallel members of cart  201 , such as, without limitation, upper vertical distal members  208  and base members  205 ,  212 , as shown. Information areas  216 ,  217  may advantageously further comprise advertising. The advertising may be screen-printed or otherwise permanently attached to advertising areas  216 ,  217 . Alternatively, the advertising may be a placard or other apparatus that is temporarily attached to advertising areas  216 ,  217 . In specific embodiments, cart  201  may also comprise an information dispenser, which may allow users of the tray to take information with them, such as a coupon or informational pamphlet. 
     In specific embodiments, the entirety of cart  201  may be constructed from non-metallic materials, to ensure that cart  201  will not set off a metal detector. In other embodiments, cart  201  may be advantageously constructed of a material that is designed not to give off false positives when being used in the screening process. In specific embodiments, all, substantially all, or some portions of cart  201  may be constructed of polyvinyl chloride (PVC), though it may be constructed of any appropriate material as understood by one of ordinary skill in the art. 
     The second cart  110  may be identical to the first cart  102  or  201 , therefore, it is not described in detail. 
     An advantage to the present system is that the first cart  102  or  201  and second cart  110  are identical carts, thus when one cart is completely filled it can be moved, by being pushed, pulled, or otherwise propelled, to the proper location where needed. In the alternative, when one cart is completely emptied it can be moved, by being pushed, pulled, or otherwise propelled, to the appropriate area to be later filled with trays  106  and  108 . 
     Furthermore, when there is a high volume of people being processed through the checkpoint, a third cart  103  can be used to hold the trays  106  and  108  to further speed up the movement of the trays  106  and  108  from the end point of the security checkpoint to be transported to the starting point of the security checkpoint. Alternatively, four or more carts may be used to further promote efficiency. 
       FIG. 11  is a top plan view diagram of a specific embodiment of the tray of the present invention. In this embodiment of tray  10 , the overall width may comprise about 21.61 inches and the interior width measure from (referring to  FIG. 3 ) one first section  48  to the opposite first section  48  may be about 15.81 inches. In  FIG. 11 , the overall vertical length may be about 13.81 inches. 
       FIG. 12  is a side view diagram of a specific embodiment of the tray of the present invention. The vertical height of this embodiment of tray  10  may be about 5.0 inches and the height of (referring to  FIG. 1 ) handle  30  may be about 0.63 inches. 
       FIG. 13  is a perspective view of a specific embodiment of the tray of the present invention illustrating one possible placement of an identification number  13  and windows  36 . 
       FIG. 14  is an end view of a specific embodiment of the tray of the present invention. It may be similar in appearance to a side view of the same embodiment. 
       FIG. 15  is a top view diagram of a specific embodiment of the tray of the present invention. In this embodiment of tray  10  the overall width may be about 13.00 inches and the interior width measure from (referring to  FIG. 3 ) one first section  48  to the opposite first section  48  may be about 8.81 inches. In  FIG. 15 , the overall vertical length may be about 12.00 inches. 
       FIG. 16  is a side view diagram of a specific embodiment of the tray of the present invention. The vertical height of this embodiment of tray  10  may be about 5.0 inches and the height of (referring to  FIG. 1 ) handle  30  may be about 0.63 inches. 
       FIG. 17  is a perspective view of a specific embodiment of the tray of the present invention illustrating the placement of an identification number  13  and windows  36 . 
       FIG. 18  is an end view of a specific embodiment of the tray of the present invention. It may be similar in appearance to a side view of the same embodiment. 
     In specific embodiments of the present invention, each component of the invention may be tested with the screening equipment to ensure that the components do not give off “false positives” when being used in the screening process. For example, each tray  10  may be tested to ensure that it does not cause a person operating the scanning device to believe that the tray has contraband in it when it in fact does not. 
     Although the illustrated embodiments of the present invention have been described herein with reference to the accompanying drawings, it is understood that the invention is not limited to those precise embodiments and that various other changes and modifications may be effected thereon by one skilled in the art without departing from the scope or spirit of the invention, and that it is intended to claim all such changes and modifications as fall within the scope of the invention.