Patent Publication Number: US-6981350-B1

Title: Projection screen apparatus

Description:
BACKGROUND AND SUMMARY OF THE INVENTION 
   The present invention relates to projection screens. More particularly, the present invention relates to portable projection screens. 
   According to the present invention, a collapsible display apparatus is provided for use with a projector configured to project an image to be watched by a viewer. The collapsible display apparatus includes a support frame moveable between a collapsed position and an expanded position, a white projection screen, a back sheet, and a lock. The support frame includes a plurality of frame member pairs and a plurality of hubs. Each frame member pair includes first and second frame members pivotably coupled together to define an X-shape. Each first and second frame member is pivotably coupled to the plurality of hubs to permit movement of the support frame between the collapsed and expanded positions. The projection screen is substantially blank, supported by the support frame, and made of a polyester fabric. The back sheet is positioned between the projection screen and the support frame to protect the projection screen from damage during movement of the support frame to the collapsed position. The lock is positioned to block movement of the support frame between the expanded and collapsed positions. The lock includes a first telescope member, a second telescope member positioned in the first telescope member, and a lock member configured to selectively block relative movement between the first and second telescope members. The second telescope member is positioned in the first telescope member when the support frame is in the collapsed position. 
   According to another aspect of the present invention, a collapsible display apparatus is provided including a support frame and a white projection screen. The support frame is moveable between a collapsed position and an expanded position. The support frame includes a plurality of frame member pairs and a plurality of hubs. Each frame member pair includes first and second frame members pivotably coupled together to define an X-shape. Each first and second frame member is pivotably coupled to the plurality of hubs to permit movement of the support frame between the collapsed and expanded positions. The projection screen is blank, supported by the support frame, and made of a polyester fabric. 
   According to another aspect of the present disclosure, a collapsible display apparatus is provided including a support frame, a projection screen, and a back sheet. The support frame is moveable between a collapsed position and an expanded position. The support frame includes a plurality of frame member pairs and a plurality of hubs. Each frame member pair includes first and second frame members pivotably coupled together to define an X-shape. Each first and second frame member is pivotably coupled to the plurality of hubs to permit movement of the support frame between the collapsed and expanded positions. The projection screen is supported by the support frame. The back sheet is positioned between the projection screen and the support frame to protect the projection screen from damage during movement of the support frame to the collapsed position. 
   According to another aspect of the present disclosure, a collapsible display apparatus is provided including a support frame, a display sheet, and a lock. The support frame is moveable between a collapsed position and an expanded position. The support frame includes a plurality of frame member pairs and a plurality of hubs. Each frame member pair includes first and second frame members pivotably coupled together to define an X-shape. Each first and second frame member is pivotably coupled to the plurality of hubs to permit movement of the support frame between the collapsed and expanded positions. The display sheet is supported by the support frame. The lock is positioned to block movement of the support frame between the expanded and collapsed positions. The lock includes a first telescope member, a second telescope member positioned in the first telescope member, and a lock member configured to selectively block relative movement between the first and second telescope members. The second telescope member is positioned in the first telescope member when the support frame is in the collapsed position. 
   According to another aspect of the present invention, a collapsible display apparatus is provided including a display sheet and a support frame supporting the display sheet. The support frame is moveable between a collapsed position and an expanded position. The support frame includes a plurality of frame member pairs and a plurality of hubs. Each frame member pair includes first and second frame members pivotably coupled together to define an X-shape. Each first and second frame member is pivotably coupled to the plurality of hubs to permit movement of the support frame between the collapsed and expanded positions. At least one of the first and second frame members has at least one substantially flat sidewall. 
   According to another aspect of the present invention, a collapsible display apparatus is provided including a display sheet and a support frame supporting the display sheet. The support frame is moveable between a collapsed position and an expanded position. The support frame includes a plurality of frame member pairs and a plurality of hubs. Each frame member pair includes first and second frame members pivotably coupled together by a pin to define an X-shape. Each first and second frame member is pivotably coupled to the plurality of hubs to permit movement of the support frame between the collapsed and expanded positions. Each of the first and second frame members has a depression defined in an outer surface of the frame members to align a tool adapted to form an aperture in the first and second frames to receive the pin. 
   According to another aspect of the present invention, a collapsible display apparatus is provided including a support frame, a white projection screen, and a border sheet. The support frame is moveable between a collapsed position and an expanded position. The support frame includes a plurality of frame member pairs and a plurality of hubs. Each frame member pair includes first and second frame members pivotably coupled together to define an X-shape. Each first and second frame member is pivotably coupled to the plurality of hubs to permit movement of the support frame between the collapsed and expanded positions. The projection screen is supported by the support frame. The border sheet is positioned around the projection screen to frame the projection screen and define a perimeter of a viewing surface of the projection screen. 
   According to another aspect of the present invention, a collapsible display apparatus is provided including a support frame, a display sheet, and a plurality of fasteners. The support frame has a front side, a first end, a second end, and a back side. The support frame is moveable between a collapsed position and an expanded position. The support frame includes a plurality of frame member pairs and a plurality of hubs. Each frame member pair includes first and second frame members pivotably coupled together to define an X-shape. Each first and second frame member is pivotably coupled to the plurality of hubs to permit movement of the support frame between the collapsed and expanded positions. The display sheet is supported on the support frame. The display sheet includes a front panel positioned on the front side of the support frame and a pair of side panels extending along the first and second ends. The side panels includes a plurality of fastener-receiving openings. The plurality of fasteners extend through the fastener-receiving openings to couple the side panels to the support frame. 
   According to another aspect of the present disclosure, a collapsible display apparatus is provided including a support frame and a blank, white projection screen detachably coupled to the support frame. The support frame is moveable between a collapsed position and an expanded position. The support frame includes a plurality of frame member pairs and a plurality of hubs. Each frame member pair includes first and second frame members pivotably coupled together to define an X-shape. Each first and second frame member is pivotably coupled to the plurality of hubs to permit movement of the support frame between the collapsed and expanded positions. 
   Additional features of the present invention will become apparent to those skilled in the art upon consideration of the following detailed description of an illustrated embodiment exemplifying the best mode of carrying out the invention as presently perceived. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A detailed description particularly refers to the accompanying figures in which: 
       FIG. 1  is a perspective view of a collapsible display apparatus according to the present disclosure showing the apparatus in an expanded position and including a detachable display sheet and a support frame supporting the display sheet; 
       FIG. 2  is a rear perspective view of the collapsible display apparatus of  FIG. 1  showing the display sheet covering a front side and ends of the support frame and portions of a back side of the support frame; 
       FIG. 3  is a perspective view of display apparatus of  FIG. 1  showing the apparatus in a collapsed position with the display sheet tucked in the collapsed support frame; 
       FIG. 4  is a perspective view of a portion of the support frame showing the support frame including a plurality of hubs, a plurality of frame members pivotably coupled to the hubs, and a telescoping lock coupled to the hubs and configured to lock the support frame in the expanded position; 
       FIG. 5  is a view similar to  FIG. 4  during movement of the support frame to the collapsed position showing the lock including a first telescope member and a second telescope member sliding in the first telescope member; 
       FIG. 6  is an exploded assembly view of the portions of the support frame shown in  FIG. 4 ; 
       FIG. 7  is a cross-sectional view taken along line  7 — 7  of  FIG. 2  showing the second telescope member positioned in the first telescope member and showing a lock member positioned in the first and second telescope members to lock the relative position of the first and second telescope members; 
       FIG. 8  is a perspective view of another portion of the support frame showing the support frame including a rubber foot coupled to one of the hubs and a pair of the frame members pivotably coupled together by a pin; 
       FIG. 9  is a cross-sectional view taken along line  9 — 9  of  FIG. 2  showing the rubber foot coupled to one of the hubs; 
       FIG. 10  is a cross-sectional taken along line  10 — 10  of  FIG. 8  showing the frame members pivotably coupled together by the pin; 
       FIG. 11  is an enlarged view of a left portion of  FIG. 7  showing various layers of material of the display sheet; 
       FIG. 12  is an enlarged view of a right portion of  FIG. 7  showing various layers of material of the display sheet; and 
       FIG. 13  is cross-sectional view taken along line  13 — 13  of  FIG. 2  showing various layers of material of the display sheet. 
   

   DETAILED DESCRIPTION OF THE DRAWINGS 
   According to the present disclosure, a projection screen apparatus  10  is provided to display images projected by a projector (not shown). Projection screen apparatus  10  is moveable between an expanded position, shown in  FIGS. 1 and 2 , and a collapsed position as shown in  FIG. 3 . To facilitate movement between the expanded and collapsed positions, apparatus  10  includes a collapsible support frame  12  that supports a display sheet  14 . 
   Display sheet  14  is configured to reflect images projected by the projector back to an audience positioned in front of apparatus  10 . Preferably, display sheet  14  remains attached to support frame  12  when collapsed as shown in  FIG. 3 . When support frame  12  is collapsed, it can be inserted into a bag (now shown), a hard shipping case (not shown), or other such container for storage or shipment. 
   Display sheet  14  is also removable from support frame  12  to permit display sheet  14  to be laundered, repaired, or replaced. Apparatus  10  includes a perimeter fastener  16 , as shown in  FIG. 2 , that removably couples display sheet  14  to a front side of support frame  12 . Apparatus  10  further includes a plurality of fasteners  18  coupled to a back side of support frame  12  that couples display sheet  14  to a back side of support frame  12  when it is in the expanded position as shown in  FIG. 2 . 
   Support frame  12  includes a plurality of sub frames  20  that are coupled together to form a matrix. According to the embodiment shown in  FIG. 2 , support frame  12  is four sub frames wide and five sub frames tall. According to alternative embodiments, other combinations of sub frames  20  are provided to support different sized display sheets. 
   Sub frames  20  include four frame pairs  22 , four front hubs  24 , and four back hubs  26 . Adjacent sub frames  20  share a frame pair  22 , a pair of front hubs  24 , and a pair of back hubs  26 . Frame pairs  22  include first and second frame members  28 ,  30  that are pivotably coupled together by a pin  32 , as shown in  FIG. 8  and pivotably coupled to a front hub  24  and a back hub  26 . Frame pairs  22  define an X-shape. Two frame pairs  22  of each sub frame  20  are positioned in a vertical orientation and the other two frame pairs  22  of a sub frame  20  are positioned in a horizontal orientation when apparatus  10  is set up for use as shown in  FIG. 2 . According to alternative embodiments of the present disclosure, other frame configurations are provided for use with display sheet  14 , such as the frames shown in U.S. Pat. Nos. 4,471,548; 4,512,097; 4,580,375; 4,800,663; 4,809,471; 4,888,895; 4,986,016; 5,123,550; 5,125,205; 5,203,126; 5,269,112; 5,826,397, or other such frames known to those of ordinary skill in the art. The disclosures of these patents are expressly incorporated by reference herein. 
   Frame members  28 ,  30  have substantially flat side walls  34  as shown in  FIG. 10 . According to the preferred embodiment, frame members  28 ,  30  are octagonal and made of extruded aluminum. According to alternative embodiments of the present disclosure, other sidewall configurations are provided such as round, triangular, square, rectangular, hexagonal, or other such shapes known to those of ordinary skill in the art. 
   Each frame member  28  includes a pair of apertures  36  sized to receive pin  32 . A washer  38  is positioned between two flat side walls  34  of first and second frame members  28 ,  30 . During assembly, pin  32  is positioned through apertures  36  with flat head  40  positioned above first member  28 . Then the lower end of pin  32  is clinched to form lower flat head  42 . 
   To facility forming of apertures  36  in first and second frame members  28 ,  30 , flat side walls  34  are provided with centered depressions  44  in each of the eight side walls  34 . Depressions  44  are preferably V-shaped and extend the entire length of each frame member  28 ,  30 . To form apertures  36 , a tool (not shown), such as a drill bit, is positioned in depression  44  at the appropriate axial position along either frame member  28 ,  30 . By positioning the bit in depression  44 , the respective aperture  36  formed by the bit will be centered in the respective sidewall  34  because depression  44  is centered in the respective sidewall. For clarity in the figures, depressions  44  are only shown in  FIG. 10 , but would otherwise be visible in the other figures. 
   As previously mentioned, each end of frame members  28 ,  30  is pivotably coupled to a respective hub  24 ,  26 . Using depressions  44  in sidewalls  34 , apertures  46  are formed in each end of frame members  28 ,  30  for receiving a pin  48  that pivotably couples the ends of frame members  28 ,  30  to hubs  24 ,  26  as shown in  FIG. 6 . 
   Each of hubs  24 ,  26  is made of ABS plastic and includes a base  50  and four ribs  52  that extends perpendicular to base  50 . Each rib  52  is slightly off set from the center of base  50  so that opposite ribs  52  do not line up. Ribs  52  include apertures  54  sized to receive a respective pin  48  that couples a frame member  28 ,  30  thereto. 
   Each rib  52  further includes an indicator  56 , shown in  FIG. 6 , that indicates which side of rib  52  the respective frame member  28 ,  30  is to be positioned. Indicator  56  is a bump or raised portion positioned on one side of each rib  52 . The opposite side of rib  52  is devoid of such a bump  56 . During assembly, the respective frame member  28 ,  30  should be positioned on the side of the respective rib  52  without indicator  56 . If a frame member  28 ,  30  is positioned on the side of a rib  52  with an indicator  56 , the respective indicator  56  will block the respective frame member  28 ,  30  from touching the respective rib  52  and not permit pin  48  to be clinched. Thus, indictors  52  indicate which side of rib  52  the respective frame member  28 ,  30  is to be positioned and blocks coupling of the respective frame member  28 ,  30  to the wrong side of a rib  52 . 
   To hold frame  12  in the expanded position, support frame  12  includes a plurality of locks  58 . During expansion and collapsing of support frame  12 , first and second frame members  28 ,  30  and front and back hubs  24 ,  26  move relative to one another. For example, during expansion, front and back hubs  24 ,  26  move toward one another. Locks  58  are positioned between respective front and back hubs  24 ,  26  to prevent such movement and thus block frame  12  from collapsing. According to alternative embodiments of the present disclosure, locks  58  are positioned between other components of the frame to block relative movement. For example, according to one embodiment, locks are positioned between frame members to block relative movement. According to another embodiment, locks are provided between the hubs and frame members to block relative movement. According to other alternative embodiments of the present disclosure, other locks known to those of ordinary skill in the art are provides for use with frame  12  and/or display sheet  14  such as the locks disclosed in the previously-mentioned U.S. patents. 
   Each lock  58  includes a first telescope member  60  coupled to one of back hubs  26  and a second telescope member  62  positioned in first telescope member  60  and coupled to one of front hubs  24  as shown in  FIGS. 4 ,  5 , and  7 . Each telescope member  60 ,  62  is octagonal having substantially flat sidewalls  64 ,  66  and depressions (not shown) similar to depressions  44  formed in first and second frame members  28 ,  30 . Furthermore, second telescope member  62  is made from the same extrusion as first and second frame members  28 ,  30 . First telescope member  60  is also made of extruded aluminum. 
   Front and back hubs  24 ,  26  include centered sleeve  68 ,  70  having apertures  67 ,  69  sized to receive ends  71 ,  72  of respective first and second telescope members  60 ,  62 . According to the preferred embodiment, aperture  71  of back hub  26  is slightly larger than aperture  69  of front hub  24  because first telescope member  60  is slightly larger than second telescope member  62 . According to an alternative embodiment of the present disclosure, the front and back hubs are identical and include a sleeve having a stepped aperture sized to receive both the first and second telescope members. The inner portion of the sleeve has a smaller inside diameter to receive the second telescope member and the outer portion of the sleeve has a larger inside diameter to receive the first telescope member. 
   Each sleeve  68 ,  70  is coupled to the respective ribs  52  of hubs  24 ,  26  and includes a pair of apertures  74  sized to receive a slotted expansion pin  76 . Similarly, ends  71 ,  72  of first and second telescope members  60 ,  62  includes apertures  77  sized to receive pin  76 . During assembly, a pin  76  is inserted through apertures  74 ,  77  to couple telescope members  60 ,  62  to respective hubs  26 ,  24 . 
   During expansion and collapsing of frame  12 , second telescope member  62  slides within first telescope member  64 . To block this relative movement and to prevent frame  12  from similar movement, a lock member  78  is provided. Each of telescope member  60 ,  62  includes an aperture  80 ,  82  sized to receive a tab  84  of lock member  78 . Lock member  78  further includes a biaser  86  that urges tab  84  into apertures  80 ,  82 . When frame  12  is in the expanded position, tab  84  is positioned in apertures  80 ,  82  and blocks relative movement of telescope members  60 ,  62 . To unlock lock  58  and permit frame  12  to collapse, tab  84  is pushed inwardly against the bias of biaser  86  so that tab  84  is no longer positioned in aperture  80  of first telescope member  60  to permit relative movement between first and second telescope members  60 ,  62 . When frame  12  is moved to the expanded position, apertures  80 ,  82  align and biaser  86  pushes tab  84  into aperture  80  to block relative movement of first and second telescope members  60 ,  62 . 
   During collapsing and expanding of frame  12 , each second telescope member  62  remains positioned in each respective first telescope member  64 . Because the ends of second telescope member  62  are never exposed, they will not catch or snag display sheet  14 . 
   As shown in  FIG. 8 , apparatus  10  further includes four rubber feet  88 , coupled to four back hubs  26  as shown in  FIG. 2 . Feet  88  support frame  12  on the floor when frame  12  is in collapsed position as shown in  FIG. 3 . 
   As shown in  FIG. 9 , back hub  26  includes a nut-receiving aperture  90  sized to receive a brass expansion nut  92 . During assembly, a bolt  94  is inserted through a fastener-receiving aperture  96  in foot  88  and turned into nut  92 . As bolt  94  is turned further into nut  92 , it expands and wedges into aperture  90  blocking removal of nut  92 , bolt  94 , and foot  88  from hub  26 . 
   As previously mentioned, display sheet  14  is configured to reflect images projected from a projector. Display sheet  14  includes a projection screen  100 , a front border sheet  102  positioned in front of projection screen  100 , and a back sheet  104  positioned behind projection screen  100 . 
   Projection screen  100  is made of white polyester fabric having a reflectivety gain of about 0.8. Screen  100  is substantially blank and free from text, graphics, or other printing or marking that would distort or detract from the images reflected by screen  100 . According to alternative embodiments of the present disclosure, screen  100  or other layers of the display sheet includes printing, graphics, or other markings that are permanent displays or advertisements. 
   Preferably, projection screen  100  is made of a swiss pique construction having a weight of about 6.0 ounces/square foot. The polyester fabric makes projection screen  100  “wrinkle free” so that when display sheet  14  is tucked within voids defined by frame  12  during storage, projection screen  100  does not develop wrinkles that would otherwise detract from the image reflected by screen  100 . 
   Front border sheet  102  and back sheet  104  are made of the same material type as projection screen  100 . However, front border sheet  102  and back sheet  104  are made of black yarn. Preferably, the yarn is made of polyester that is dyed black so that the dye is integral with the polyester rather than applied to the surface of the polyester yarn before or after weaving. This prevents bleeding of the black dye during cleaning or laundering of display sheet  14 . Because projection screen  100 , front border sheet  102 , and back sheet  104  are made of the same material type, they have the same expansion coefficient and same responses to environmental changes such as temperature, humidity, etc. so that wrinkles, puckers, and other imperfects are reduced due to environmental changes. 
   Border sheet  102 , projection screen  100 , and back sheet  104  are acoustically transparent. Thus, audio speakers (not shown) can be positioned within frame  12  or elsewhere behind display sheet  14  and the sound produced by the audio speakers will transmit through to the audience on the opposite side of projection screen  100 . 
   Front border sheet  102  “frames” projection screen  100  and includes a rectangular opening  106  that defines a width  108  and height  110  of the viewing surface of projection screen  100 . Projection screen  100  shown in  FIG. 1  has a viewing surface with a width  108  of 80 inches and a height  110  of 100 inches. Front sheet  102  has a width of about 2 inches around the top and sides of screen  100  and height of about 42 inches below screen  100 . According to alternative embodiments, screens having viewing surface areas (height by width) of 72 inches by 96 inches; 90 inches by 121 inches; 108 inches by 146 inches. According to alternative embodiments, other viewing surface sizes are provided. 
   Front sheet  102  and back sheet  104  extend from the top of frame  12  to the bottom of frame  12 . Screen  100  extends from the top of frame  12  and terminates slightly below rectangular opening  106 . As shown in  FIG. 13 , front sheet  102  and back sheet  104  wrap around the ends of frame  12  and extend around to the back of frame  12  before terminating. Screen  100  terminates at the ends of frame  12 . 
   To attach display sheet  14  to frame  12 , display sheet  14  includes a perimeter fastener  112  that corresponds to perimeter fastener  16  coupled to frame  12  and a plurality of apertures  113  that correspond to fasteners  18  coupled to the back of frame  12 . As shown in  FIGS. 11–13 , perimeter fastener  112  includes a horizontal, two inch wide strip  114  of hook-and-loop type fasteners (also known as VELCRO-brand fasteners) that extends along the top of frame  12  from the back of frame  12  adjacent to one end of frame  12 , along the respective end of frame  12 , along the front of frame  12 , along the opposite end of frame  12 , and around to the back of frame  12  as partially shown in  FIG. 13 . An identical horizontal strip  114  is provided along the bottom of frame  12 . 
   As shown in  FIG. 11 , a similar two inch vertical strip  116  of hook-and loop type fasteners is provided for perimeter fastener  112  along the front of frame  12  adjacent the bottom of upper horizontal strip  114 . An identical vertical strip  116  is positioned at the opposite end on the front of frame  12 . Horizontal strips  114  and vertical strips  116  cooperate to define a rectangular perimeter of hook-and-loop type fasteners along the front perimeter of frame  12 . 
   Similar to vertical strips  116 , two inch vertical strips  118  of hook-and-loop type fasteners are provided on the back of display sheet  14  as shown in  FIG. 12 . Vertical strips  118  extend from the top of bottom horizontal strip  114  to the bottom of top horizontal strip  114  as shown in  FIG. 12 . 
   Border sheet  102 , screen  100 , back sheet  104 , and horizontal and vertical strips  114 ,  116  are permanently coupled together. Preferably, sheet  102 , screen  100 , sheet  104 , and strips  114 ,  116  are sewn together along two rows that follow the perimeter of the front of frame  12 . Additionally, border sheet  102 , screen  100 , and back sheet  104  are sewn together just below the bottom of rectangular opening  106 . Border sheet  102 , back sheet  104 , and horizontal strips  114  are sewn together along ends and back of frame  12 . Similarly, border sheet  102 , back sheet  104 , and vertical strips  118  are sewn together from top to bottom. 
   Perimeter fastener  16  includes horizontal and vertical strips  120 ,  122  of hook-and-loop type fasteners that correspond to horizontal and vertical strips  114 ,  116  of perimeter fastener  112 . Horizontal and vertical strips  120 ,  122  define a rectangular perimeter of hook-and-loop type fasteners along the front of frame  12 . 
   Perimeter fastener  16  further includes a rectangular flexible frame  124  behind horizontal and vertical strips  120 ,  122 . Flexible frame or webbing  124  is made of polypropylene webbing. Webbing  124  provides a rectangular frame work between front hubs  24  to keep the front perimeter of display sheet  14  taut. Webbing  124  include a pair of horizontal strips  126  and a pair of vertical strips  128  similar to horizontal and vertical strips  120 ,  122  but does not extend around the ends to the back of frame  12 . 
   Perimeter fastener  16  further includes a pair of horizontal strips  130  of hook-and-loop type fasteners and a pair of vertical strips  132  of hook-and-loop type fasteners that correspond to horizontal and vertical strips  126 ,  128 . A two-inch square  134  of hook-and-loop type fastener is provided for each perimeter front hub  24 . Squares  134  include an adhesive backing  136  that is coupled to each respective front hub  24 . Similarly a two-inch square  138  of hook-and-loop type fastener is provided for each back hub  26  positioned along the ends of frame  12 . Squares  138  include an adhesive backing  140  that is coupled to each respective back hub  26 . Squares  136  couple with horizontal and vertical strips  130 ,  132 . 
   Respective horizontal and vertical strips  120 ,  122 , webbing  124 , respective horizontal and vertical strips  130 ,  132 , and squares  134  are coupled together with plastic grommets  140  as shown in  FIG. 13 . Each grommet  140  includes an aperture  142  through which a fastener  144 , such as a pan screw, is inserted and turned into an expansion nut  92  to couple fastener  16  to each respective front hub  24 . Squares  136  prevent the respective portions of perimeter fastener  16  from rotating about respective fasteners  144 . 
   Border sheet  102 , back sheet  104 , and horizontal strip  144  are coupled together with plastic grommets  146  as shown in  FIG. 12 . Each grommet  146  includes an aperture  148  through which one of fasteners  18  is inserted to couple the back of display sheet  14  to each respective back hub  26 . Squares  138  prevent the respective portions of perimeter display sheet  14  from rotating about respective fasteners  18 . 
   Fasteners  18  includes a base  150  coupled to back hub  26  by a pair of screws  152 , shown in  FIG. 6 , a post  153 , and a cross member  154  pivotably coupled to post  153  by a pin  156 . To couple display sheet  14  to one of fasteners  18 , cross member  154  is rotated until it is aligned with post  153 . Aligned cross member  154  is inserted through aperture  148  of grommet  146 . Cross member  154  is released and moves to a position substantially perpendicular to post  152  as shown in  FIGS. 4 and 12 . When in this position, cross member  154  blocks removal of grommet  146  from fastener  18  and frame  12 . 
   To remove display sheet  14  from fasteners  18 , cross member  154  is aligned with post  152  so that grommet  146  can be removed from post  152  with cross member  154  blocking such removal. Once display sheet  14  is removed from fasteners  18 , frame  12  is collapsed by unlocking locks  58 . When frame  12  is collapsed, display sheet  12  is tucked into the voids created in frame  12  as shown in  FIG. 3 . In  FIG. 3 , the ends of display sheet  14  are shown folded forward over the front of display sheet  14  to show details of frame  12 . 
   If necessary or on a periodic basis, display sheet  14  can be completely removed from frame  12 . Display sheet  14  is first removed from fasteners  18  as described above. Next, display sheet  14  is removed from frame  12  by peeling perimeter fastener  112  of display sheet  14  from perimeter fastener  16  so that the hook-and-loop type fasteners uncouple. Then, display sheet  14  can be laundered, repaired, or replaced if necessary. 
   To couple display sheet  14  back on frame  12 , perimeter fastener  112  of display sheet  12  is positioned back over perimeter fastener  16  and display sheet  14  is coupled to fasteners  18  positioned on back of frame  12 , if necessary. 
   Preferably, instructions for the assembly, installation, and/or use of projection screen apparatus  10  are provided with projection screen apparatus  10  or otherwise communicated to permit a person or machine to assemble, install and/or use projection screen apparatus  10 . Such instructions may include a description of any or all portions of projection screen apparatus  10  and/or any or all of the above-described assembly, installation, and use of projection screen apparatus  10  or components of projection screen apparatus  10 . The instructions may be provided on separate papers and/or on the packaging in which projection screen apparatus  10  is sold or shipped. These instructions may also be provided over the Internet or other communication system. Furthermore, the instructions may be embodied as text, pictures, audio, video, or any other medium or method of communicating instructions known to those of ordinary skill in the art. 
   Unless otherwise stated herein, the figures are proportional. Although the present invention has been described in detail with reference to preferred embodiments, variations and modifications exist within the scope and spirit of the present invention as described and defined in the following claims.