Abstract:
Embodiments of apparatuses, methods and systems for deployable projection screens are generally described herein. Other embodiments may be described and claimed.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]     The present application claims priority to U.S. Provisional Application No. 60/678,635, filed May 5, 2005, entitled “PROJECTION SCREENS,” the entire contents of which is hereby incorporated by reference. 
     
    
     FIELD  
       [0002]     Disclosed embodiments of the present invention relate to the field of projection systems, and more particularly to the use of a deployable projection screen in such systems.  
       BACKGROUND  
       [0003]     Projection systems project images from a small display, or light valve, found in a projection device, onto a viewing surface. Although the viewing surface may be any flat surface, using a projection screen as the viewing surface may facilitate reflection of the projected image with detail and contrast suitable for viewing over a wide range of angles. A high-quality projection screen will typically reject a substantial portion of the ambient light surrounding the projection system, while still providing sufficient viewing angles of the projected image.  
         [0004]     The images projected by projection systems are capable of being very large, which, in turn, corresponds to the use of a large projection screen. However, some users may find a large projection screen distracting while not in use.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]     Embodiments of the invention are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings, in which the like references indicate similar elements and in which:  
         [0006]      FIGS. 1   a - 1   c  illustrate perspective views of a projection system in accordance with an embodiment of the present invention;  
         [0007]      FIGS. 2   a - 2   c  illustrate a side view of a foldable projection screen transferring between a stored state and a deployed state, in accordance with an embodiment of the present invention;  
         [0008]      FIG. 3  illustrates a side view of a joint between two adjacent slats of a foldable projection screen, in accordance with an embodiment of the present invention;  
         [0009]      FIG. 4  illustrates a front view of a projection screen having an inflatable frame, in accordance with an embodiment of the present invention;  
         [0010]      FIG. 5  illustrates a cross-sectional view of the projection screen of  FIG. 4 , in accordance with an embodiment of the present invention;  
         [0011]      FIGS. 6   a - 6   b  illustrate front views of a tensioned projection screen in various stages, in accordance with an embodiment of the present invention;  
         [0012]      FIGS. 7   a - 7   b  illustrate a front view of a projection screen with telescopic frame segments in deployed and stored states, in accordance with an embodiment of the present invention;  
         [0013]      FIG. 8  illustrates a front view of a projection screen using variable-tensioned segmented rollers, in accordance with an embodiment of the present invention;  
         [0014]      FIG. 9  illustrates a front view of a projection screen using shape-segmented rollers, in accordance with an embodiment of the present invention;  
         [0015]      FIGS. 10   a - 10   e  illustrate various views of a flexible frame projection screen in various stages of deployment, in accordance with an embodiment of the present invention; and  
         [0016]      FIG. 11  illustrates a flexible frame projection screen, in accordance with an embodiment of the present invention.  
     
    
     DETAILED DESCRIPTION  
       [0017]     In the following detailed description reference is made to the accompanying drawings that form a part hereof, wherein like numerals designate like parts throughout, and in which is shown, by way of illustration, specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the embodiments of the present invention. Directions such as up, down, back, and front may be used in the discussion of the drawings. These directions are used to facilitate the discussion and are not intended to restrict the application of embodiments of this invention. Therefore, the following detailed description is not to be taken in a limiting sense.  
         [0018]     Further, various operations will be described as multiple discrete operations, in turn, in a manner that is most helpful in understanding the present invention; however, the order of description should not be construed as to imply that these operations are necessarily order dependent. In particular, these operations need not be performed in the order of presentation.  
         [0019]     The phrase “in one embodiment” is used repeatedly. The phrase generally does not refer to the same embodiment; however, it may. The terms “comprising,” “having,” and “including” are synonymous, unless the context dictates otherwise.  
         [0020]     In providing some clarifying context to language that may be used in connection with various embodiments, the phrase “A/B” means “A or B.” The phrase “A and/or B” means “(A), (B), or (A and B).” The phrase “at least one of A, B and C” means “(A), (B), (C), (A and B), (A and C), (B and C) or (A, B and C).” The phrase “(A)B” means “(B) or (A and B),” that is, A is optional.  
         [0021]     Various embodiments of the present invention include projection screens designed to be flat in a deployed state, yet disappear into a structure while in a stored state. Embodiments described and discussed below may be employed in front- and/or rear-projection systems.  
         [0022]      FIG. 1   a  illustrates a perspective view of a projection system  100  including a housing  104  containing a projection device  108 , in accordance with an embodiment of the present invention. The housing  104  may be a piece of furniture, e.g., a coffee table. In one embodiment the projection device  108  may be recessed within a projector cavity of the housing  104  and covered with a transparent or a removable cover. During use, the projection device  108  may operate from within the projector cavity, or it may be extended outward by a certain amount.  
         [0023]     Deployment of a projection screen  112  is shown in an intermediate state in  FIG. 1   b  in accordance with an embodiment of the present invention. The projection screen  112  may include rollers  116  and screen material  120 . The screen material  120  may have optical attributes suitable to at least facilitate viewing of an image projected thereon. These optical attributes may include, for example, gain, contrast (e.g., ambient light rejection), resolution, uniformity, projection format, etc.  
         [0024]     Furthermore, the projection screen  112  may have physical attributes suitable to facilitate repeated transitions between contracted storage (or “stored”) state and an expanded projection (or “deployed”) state without materially affecting optical attributes of the screen material. The physical attributes may include, for example, flexibility, noncreasing, pliability, etc.  
         [0025]     Values of these attributes (both physical and optical) may be provided with respect to design constraints and/or objectives of a particular embodiment.  
         [0026]     The rollers  116  may unroll the screen material  120  into the deployed state depicted in  FIG. 1   c . A frame (not shown) may be coupled to the rollers  116  to facilitate the deployment and support of the projection screen  112 . The frame may be automatic or manually operated. In one embodiment, the frame may include a scissor-jack design.  
         [0027]     With the projection screen  112  fully deployed, the projection device  108  may project an image for viewing. In various embodiments, the projection screen  112  and/or the projection device  108  may be adapted to accommodate the relative positioning of the two components. For example, the projection device  108  may be a steep-angled projection device to accommodate for the relative closeness of the two components.  
         [0028]     In an embodiment the relative positioning of the projection device  108  and the projection screen  112  may be adjusted to, e.g., provide for a larger/smaller projected image. The adjustment of the relative positioning may be done by moving the projection screen  112  and/or the projection device  108 .  
         [0029]     In an embodiment, a second projection screen (not shown) may be adapted to be deployed at a second distance from the projection device  108  to accommodate a different image size than the projection screen  112 . In this embodiment, a user may view a smaller image, e.g., for watching a television program, on the projection screen  112 , or a larger image on the second screen, e.g., for watching a video in a wide-screen display format, that is further from the projection device  108 .  
         [0030]      FIG. 2   a  illustrates a side view of a foldable projection screen  200  stored within a housing  204 , in accordance with an embodiment of the present invention. The projection screen  200  and housing  204  may be substantially interchangeable with the like-named elements discussed above with reference to the projection system  100 .  
         [0031]     In this embodiment, the projection screen  200  may include slats  208 . The slats  208  may provide a supportive substrate for the projection screen material disposed on one side of the slats  208 . Each of the slats  208  may be coupled to an adjacent slat  208  by a hinge  212  at the edge. In one embodiment the type of hinge used may have two pivot points so that it may fold in both directions.  
         [0032]     In one embodiment, the projection screen  200  may have one or more bi-stable springs designed to facilitate the transition of the projection screen from the stored state depicted in  FIG. 2   a , through an intermediate state depicted in  FIG. 2   b , to the deployed state depicted in  FIG. 2   c , and back. In various embodiments, the spring(s) may be embedded within the slats  208  or placed on the backside of the screen (backside being the side opposite the viewing side).  
         [0033]     In one embodiment, the screen material may be loosely coupled to the slats  208 . For example, in one embodiment, the screen material may be coupled to the top edge of the top slat  208  and the bottom edge of the bottom slat  208 . When the projection screen  200  is deployed, the screen material may be stretched taut across one side of the slats  208 . In other embodiments, the screen material may be coupled more closely to the slats  208 , e.g., directly adhered to at least a portion of the face of the slats  208 .  
         [0034]     In one embodiment, e.g., the embodiment depicted in  FIG. 3 , the adjoining edges of slats  300 , which may be substantially interchangeable with slats  208 , may be geometrically designed to reduce the spacing at a junction  304  between adjacent slats  300  viewed from the front while they are in the deployed state. So designed, the surface of adjoining slats may be substantially flush with one another giving the appearance of a substantially continuous viewing surface. In this embodiment, the slats  300  are angled to pinch together at the junction  304 .  
         [0035]      FIG. 4  illustrates a front view of a projection screen  400  having an inflatable frame  404 , in accordance with an embodiment of the present invention.  
         [0036]     The frame  404  may be coupled to a mechanical actuator, e.g., a pump  408 . In an embodiment, the pump  408  may be a high volume low pressure (HVLP) pump. As the pump  408  is activated, the frame  404  may fill with air and provide a sufficiently rigid structure. The projection screen material  412 , which may be adhered to the frame  404 , may become suitably taut upon inflation of the frame  404 .  
         [0037]     In an embodiment, the deployed projection screen  400  may have a form factor suitable for indoor viewing. For example, the projection screen  400  may be used interchangeably with the projection screen  112  in the projection system  100 . In this embodiment, the pump  408  may operate from a storage location in the housing  104 .  
         [0038]     Storage of the projection screen  400  may take place by deflating the frame  404  and storing the projection screen material  412  within a screen cavity of a housing.  
         [0039]      FIG. 5  illustrates a cross-sectional view of the projection screen of  FIG. 4 , in accordance with an embodiment of the present invention. In this embodiment, the projection screen material  412  may be folded over the frame  404 .  
         [0040]      FIG. 6  illustrates a front view of a tensioned projection screen  600 , in accordance with an embodiment of the present invention. In this embodiment, a storage structure  602  may store screen material  608 . Supporting features, such as cables  604 , may extend substantially orthogonal to the storage structure  602 . The cables  604  may also be stored in the storage structure  602  and may be retractably deployed by a constant-force spring, for example. In other embodiments, the cables  604  may be semipermanently disposed. In various embodiments, the cables  604  may be coupled to, or independent from, the storage structure  602 .  
         [0041]     In one embodiment, the screen material  608  may be coupled to the cables  604 . More particularly, grommets  612  may be coupled to the cables  604  and attachment points, e.g., eyelets  616 , found on a perimeter of the screen material  608 . While eyelets  616  are shown on two edges of the screen material  608 , other embodiments may additionally/alternatively have them elsewhere.  
         [0042]      FIG. 6   b  illustrates an embodiment where the screen material  608  may be pulled completely out of the storage structure  602  so that the perimeter of the screen material  608  may be exposed in its entirety. Suspension of the screen material  608  may cause the appearance of a floating screen.  
         [0043]     In an embodiment, the screen material  608  may include a border  620  surrounding a viewing area  624 . The viewing area  624  may have optical attributes suitable to facilitate viewing of images projected thereon. The border  620  may have optical attributes suitable to provide contrast to the viewing area  624 , e.g., a black matte to absorb light. Borders, similar to border  620 , may be applied to any other projection screen discussed herein.  
         [0044]     Suspension of the screen material  608  may also facilitate positioning of the viewing area  624  and/or concealment of the storage structure  602 . For example, the storage structure  602  may be disposed in/at a high ceiling and the screen material  608  may be pulled down, along the cables  604 , to the desired location.  
         [0045]     In various embodiments, the screen material  608  may include a top perimeter edge having one or more grommets/attachment points similar to the side edges. This may facilitate storage and/or vertical tensioning of the screen material  608 . In other embodiments, other mechanical features may be additionally/alternatively employed to facilitate storage and/or vertical tensioning of the screen material  608   
         [0046]     While the above embodiment illustrates the projection screen  600  being deployed by the screen material  608  being pulled down from the storage structure  602 , in other embodiments, the projection screen  600  may be deployed by the screen material  608  being pulled up or sideways out of the storage structure  602 .  
         [0047]      FIG. 7   a  illustrates a rear view of a projection screen  700  with telescopic frame segments  704  in a stored state, in accordance with an embodiment of the present invention. In the stored state, a storage structure  708  may house screen material  712  and the frame segments  704  may be collapsibly disposed within one another. In the deployed state depicted in  FIG. 7   b , the frame segments  704  may be extended, along with the screen material  712 . Braces  716  may be positioned between the frame segments  704  to facilitate crosswise support.  
         [0048]      FIG. 8  illustrates a front view of a projection screen  800  using variable-tensioned segmented rollers  804 , in accordance with an embodiment of the present invention. In this embodiment, screen material  808  may be coupled to the segmented rollers  804  and a cross-bar  812 . This embodiment may facilitate the application of different quantities of tension across the face of the screen  800 . For example, in one embodiment, in order to flatten the edges, the rollers  804  toward the outside may provide a greater tension than the rollers  804  toward the middle. The tension applied by the rollers  804  may be countered by the weight of the cross-bar  812  or by coupling the cross-bar  812  to a structure.  
         [0049]     In various embodiments, the rollers  804  may be disposed within a housing (not shown).  
         [0050]      FIG. 9  illustrates a front view of a projection screen  900  using shaped-segmented rollers  904 , in accordance with an embodiment of the present invention. In this embodiment, a screen material  908  may be coupled to the rollers  904  and a cross-bar  912 . The shape of some of the rollers  904 , e.g., the trapezoidal shape of the outer rollers  904 , may facilitate the provision of both a vertical force and a horizontal force. The combination of the vertical and horizontal forces may facilitate even tension across the face of the projection screen  900 . In one embodiment, the cross-bar  912  may be curved in order to complement this tension. In this embodiment, the curvature of the cross-bar  912  may be within a border section.  
         [0051]     Those skilled in the art will recognize that the trapezoidal shape of the outer rollers  904  is as depicted in the plan view illustrated in  FIG. 9 . The actual three-dimensional geometrical shape may be, e.g., a conical portion having a diameter that increases with an increased distance from a vertical centerline of the projection screen  900 .  
         [0052]      FIGS. 10   a - 10   e  illustrate a flexible frame projection screen  1000  in a deployed state, transitional states, and a stored state, respectively, in accordance with an embodiment of the present invention. The projection screen  1000  may have a frame  1004  with screen material  1008  attached to it, substantially at the perimeter of the screen material  1008 . The frame  1004  may be constructed of a material, e.g., spring steel, which is sufficiently flexible to allow the projection screen  1000  to be repeatedly transitioned between deployed and stored states through a combination of bending, twisting, rotating, folding, etc.  
         [0053]     In an embodiment, the frame  1004  may be sufficiently flexible to allow the projection screen  1000  to transition from the deployed state, illustrated in  FIG. 10   a , to the stored state, illustrated in  FIG. 10   d , and vice versa. In an embodiment, transition of the projection screen  1000  from the deployed state to the stored state may be initiated by a combination of transitional forces, e.g., compressive forces  1012  and rotational forces  1016 , being applied to a plurality of perimeter points of the frame  1004 .  
         [0054]      FIGS. 10   b - 10   c  illustrate transitional states of the projection screen  1000  in accordance with an embodiment of the invention. The bending and compressing of the frame  1004  may release tension of the screen material  1008 . In this embodiment, a perimeter point  1020  may then be folded inside of perimeter point  1024 . Similarly, perimeter point  1028  may be folded inside of perimeter point  1032 .  
         [0055]      FIGS. 10   d - 10   e  respectively illustrate a side view and a front view of the projection screen  1000  in the stored state in accordance with embodiments of this invention. In this embodiment, the projection screen  1000  has been folded over onto itself approximately three times. Accordingly, the surface area that the projection screen  1000  occupies while in the stored state may be approximately one-ninth of the surface area that the projection screen  1000  occupies while in the deployed state. In other embodiments, the projection screen  1000  may be folded in a different manner resulting in other surface area reductions. Various embodiments of the present invention may include a surface area of the stored state being no more than 50% of the surface area of the deployed state.  
         [0056]     The projection screen  1000  may be transitioned from the stored state to the deployed state in a reverse manner with substantially equal and opposite transition forces applied. As used herein a compressive force may be positive or negative in order to compress or expand the frame  1004 , respectively. Similarly, as used herein a retractive force may be positive or negative in order to retract or extract the frame  1004 , respectively.  
         [0057]     While the projection screen  1000  in the deployed state is shown with a circular aspect from the front view, other embodiments may include deployed state aspects other than circular, e.g., substantially rectangular or elliptical. For example,  FIG. 11  illustrates a projection screen  1100  having a substantially elliptical deployed aspect from the front view, in accordance with an embodiment of this invention.  
         [0058]     In this embodiment, the projection screen  1100  may have a flexible frame  1104 , which may be similar to frame  1004  described above. The projection screen  1100  may also include screen material  1108  attached to the frame  1104  at, or near, the perimeter of the screen material  1108 . The screen material  1108  may include a border  1112  similar to the border discussed and described above.  
         [0059]     In this embodiment, the projection screen  1100  may also include a mechanical actuator  1116  coupled to the frame  1104  at anchors  1120  and  1124  located at perimeter points of the frame  1104 . The mechanical actuator  1116  may be capable of transitioning the projection screen  1100  between a deployed and stored state in a manner similar to the transitioning of the projection screen  1000  shown and described above. In this embodiment, the mechanical actuator  1116  may provide a combination of compressive forces  1128  and rotational forces  1132  upon the frame  1104  to transition the projection screen  1100  from the deployed state to the stored state. The mechanical actuator  1116  may provide rotational forces  1132  by rotating mechanisms  1136  and  1140  coupled to respective anchors  1120  and  1124 . The mechanical actuator  1116  may provide the compressive forces  1128  by moving supports  1144  and  1148  toward one another. The supports  1144  and  1148  may be on a track (not shown) located within a storage device.  
         [0060]     The mechanical actuator  1116  may also provide retractive forces  1152  via the supports  1144  and  1148 . For example, in an embodiment using the projection screen  1100  within the system  100  shown and described in  FIG. 1 , the mechanical actuator  1116  may fold the frame  1104  (by applying compressive forces  1128  and rotational forces  1132 ) over onto itself and then retract the projection screen  1100  within the housing  104  (by applying retractive forces  1152 ).  
         [0061]     In various embodiments, the mechanical actuator  1116  may provide transitional forces in other manners. Furthermore, in various embodiments the mechanical actuator  1116  may be automatically or manually operated.  
         [0062]     In various embodiments, the projection screens  400 ,  600 ,  700 ,  800 ,  900 ,  1000 , and/or  1100  may be used interchangeably with the projection screen  112  within the projection system  100 .  
         [0063]     Although specific embodiments have been illustrated and described herein for purposes of description of the preferred embodiment, it will be appreciated by those of ordinary skill in the art that a wide variety of alternate and/or equivalent implementations calculated to achieve the same purposes may be substituted for the specific embodiment shown and described without departing from the scope of the present invention. Those with skill in the art will readily appreciate that the present invention may be implemented in a very wide variety of embodiments. This application is intended to cover any adaptations or variations of the embodiments discussed herein. Therefore, it is manifestly intended that this invention be limited only by the claims and the equivalents thereof.