Patent Publication Number: US-2006001647-A1

Title: Hand-held display device and method of controlling displayed content

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      The subject matter of this application is related to the subject matter of U.S. Provisional Patent Application Ser. No. 60/563,937, filed Apr. 21, 2004 and entitled “Mobile Computing Devices” (Attorney Docket No. P374.102.101) and U.S. Provisional Patent Application Ser. No. 60/564,631, filed Apr. 21, 2004 and entitled “Mobile Computing Devices” (Attorney Docket No. P374.103.101), priority to which is claimed under 35 U.S.C. §119(e) and an entirety of both of which are incorporated herein by reference. 
    
    
     BACKGROUND  
      The present invention relates to hand-held electronic devices having a display screen. In particular, the present invention relates to a device and method for altering or moving (e.g., browsing) the content displayed on a hand-held device display screen and for selecting a desired content sub-set from otherwise moving displayed content.  
      A wide variety of hand-held, electronic devices include a display screen for displaying information or content to the user. Exemplary devices include portable computing device, personal digital assistants, mobile phones, digital cameras, etc. To facilitate mobility of these and other hand-held electronic devices, the display screen is relatively small, especially when compared to conventional desktop computer display screens. This physical size requirement inherently limits the amount and/or format of information displayed on the hand-held device display screen at any one point in time. That is to say, while other components (e.g., processor, memory, etc.) associated with most hand-held electronic display devices are normally capable of electronically maintaining large data items (e.g., spreadsheets, images, word processing documents, webpages, etc.), the limited size of the actual display screen and user comprehension needs dictate that only a portion of an individual item can be displayed at any one time. Given that many items are formatted for display on a desktop computer display screen, partial displays on a hand-held display screen are a common occurrence.  
      For example, a user may wish to view an internet website page via the hand-held device display screen. Many website pages are formatted (e.g., amount and font size of text, images, etc.) for viewing on a desktop computer display screen. Were this same content to be reduced in size to “fit” on the hand-held device&#39;s reduced-sized display screen, it may be virtually impossible for the viewer to comprehend (e.g., read) the content thereof. Instead, the hand-held display device&#39;s processor selects a portion of the desired webpage for display on the display screen (e.g., the hand-held display device&#39;s display screen displays one-eighth of the content that would otherwise be shown in its entirety on a “standard” desktop computer display screen).  
      To account for the physical size limitations associated with hand-held device display screens, most of these devices provide user-browsing functions. These functions typically include zoom (i.e., displayed content is enlarged or reduced), pan (i.e., displayed content “moves” horizontally left-to-right or right-to-left relative to the display screen), and tilt or scroll (i.e., displayed content “moves” vertically up or down relative to the display screen). With these features, then, a user can readily “move” about and view all portions of a particular item that is otherwise being displayed on a truncated basis..  
      A typical mechanism by which a user can effectuate “browsing” or other displayed content alterations entails manual mouse or touch screen activation. For example, the hand-held display device can include a touch pad with touch keys labeled “zoom,” “pan,” and “tilt”. Selecting or depressing one of these touch keys (such as with the user&#39;s finger and/or a stylus) causes the hand-held device to alter the displayed content in a corresponding fashion. While this approach is widely accepted and understood by most users, it is often times highly inconvenient. As a point of reference, conventional browsing mechanisms require both of the user&#39;s hands; one hand holding the device and the other hand operating the browse mechanism (e.g., manipulating the stylus, pressing the touch key, etc.). In many instances, both of the user&#39;s hands are not readily available. For example, a user may be traveling in an environment requiring that one of the user&#39;s hands holds onto a structure to maintain stability (e.g., a user standing on a train while holding a support strap). Similarly, the user may be in an environment that does not provide a flat, stable surface for supporting the hand-held device during a browsing operation. Also, many users may not posses the manual dexterity required to operate the relatively small keys associated with a hand-held electronic device. Even further, and perhaps most problematic, purchasers of hand-held display devices have come to expect increasing levels of operating simplicity and convenience. As a result, users may be annoyed by any perceived inconvenience (such as two-handed browsing) that otherwise detracts from true “mobility” of an electronic hand-held display device. This convenience factor may reduce the user&#39;s satisfaction with a particular hand-held display device, a situation clearly not desired by the device manufacturer.  
      In light of the above concerns, efforts have been made to facilitate hand-held device display screen browsing in a manner that does not require both of the user&#39;s hands. In particular, efforts have been made to incorporate sensors into the hand-held device that operate to sense and quantity movements of the device relative to the user and/or relative to a “standard” position (e.g., relative to the earth). Displayed content is then browsed or altered in a manner corresponding with the sensed movements. For example, PCT Publication No. WO 01/27735 entitled “Operation Method of User Interface of Hand-Held Device” describes a hand-held display device including an acceleration measurement circuit for detecting certain movements of the device in three-dimensional space during use thereof, with displayed data changing in a manner corresponding with the sensed movements in a cause-consequence relationship. Similarly, PCT Publication No. WO 98/14863 entitled “Hand-Held Image Display Device” describes a hand-held image display device including two tilt sensors capable of sensing tilting or rotation of the device about a particular axis. The displayed image scrolls in the direction the hand-held device is rotated via reference to the tilt sensor information. Also, U.S. Patent Application Publication No. 2002/0175896 A1 entitled “Method and Device for Browsing Information on a Display” describes a hand-held device incorporating an acceleration sensor or other device for calculating a tilt of the hand-held device relative to a reference tilt angle (that in turn is defined with reference to the earth). In addition, a video camera can be used to measure the orientation and location of the hand-held device relative to the user such as by measuring the distance to a certain reference point, thus facilitating measurement of tilting or movement.  
      With the above-described techniques, as well as other suggested concepts, the hand-held device must include additional, discrete sensors, and rely upon complicated algorithms for measuring spatial characteristics of the hand-held device relative to the earth and/or relative to the user. These sensors increase overall costs. Further, the measurement-deduction algorithms occupy significant memory space and processing speed, and may not be accurate.  
      Regardless of the manner in which display screen content browsing is facilitated, an additional concern is the ability of the user to readily select or act upon a desired sub-set of an otherwise moving display content. For example, where a browsing feature is employed to “move” displayed content in a left-to-right fashion (i.e., pan), and the user wishes to zoom on a particular item being displayed, link to an internet website address being displayed, etc., the user must stop the panning action, move a cursor (e.g., such as a mouse-controlled cursor) over the desired content, and then initiate the desired activity. As previously described, many conventional hand-held display device browsing features require cursor movement to effectuate the desired browsing operation, making it impossible to simultaneously “stop” the browsing operation and act upon a desired content sub-set. Similarly, with suggested sensor-based browsing mechanisms in which the user simply rotates or moves the hand-held device to effectuate the browsing operation, the cursor will “move” with the moving display. Thus, the user must follow a first manual sequence to stop browsing (e.g., depress a touch key), followed by a second manual sequence to reposition the cursor “over” the desired content sub-set. Again, any hand-held display device operating requirement that is even perceived as being inconvenient can undesirably detract from the user&#39;s overall satisfaction.  
      Hand-held electronic display devices continue to increase in popularity. Many features associated with such devices, such as display clarity, processing speed, etc., have undergone multiple improvements. However, the method by which such devices facilitate display content browsing and/or action upon desired content has remained essentially unchanged. Thus, several areas for improvement exist.  
     SUMMARY  
      One aspect of the present invention relates to a method for altering or browsing content displayed on a display screen of a hand-held device by a user handling the hand-held device. The method includes capturing a first user image of the user relative to the device. A second user image of the user relative to the device is subsequently captured. A spatial attribute of the first user image is compared with a corresponding spatial attribute of the second user image. Finally, content displayed on the display screen is altered based upon the comparison. In one embodiment, the content displayed on the display screen is altered by zooming, panning, or tilting (i.e., scrolling) the displayed content. In another embodiment, the compared spatial attributes relate to an area of the user image relative to a reference frame. In another embodiment, the spatial attributes relate to a position of the user image (or identifiable feature thereof) relative to a reference frame.  
      Another aspect of the present invention relates to a hand-held device for displaying content to a user. The hand-held device includes a housing, a display screen, a camera system, and a processor. The housing maintains the display screen, the camera system, and the processor. In this regard, the camera system includes a lens that is positioned by the housing such that the lens and the display screen face in a similar direction. The processor is electronically connected to the display screen and the camera system. Further, the processor is adapted to prompt the display screen to display content. The processor is further adapted to capture a first image of a user of the hand-held device relative to the hand-held device via the camera system, and determine a spatial attribute of the first user image. Similarly, the processor is adapted to capture a second image of the user relative to the hand-held device and determine a spatial attribute of the second user image otherwise corresponding with the spatial attribute of the first user image. Finally, the processor is adapted to compare the spatial attributes of the first and second images and alter content displayed on the display screen based upon the comparison. With this construction, the hand-held device is capable of, for example, zooming, panning, or tilting the displayed content based upon a comparison of captured images.  
      Yet another aspect of the present invention relates to a method of operating a hand-held display device including a display screen. The method includes prompting the display of a fixed cursor on the display screen, a location of the fixed cursor being fixed relative to a border of the display screen. Moving content is displayed on the display screen. To this end, the moving content is selected from the group consisting of zooming, panning, and tilting content. Regardless, the fixed cursor is displayed on the display screen over the moving content. The hand-held device is then operated to position a desired content sub-set at an activation position on the display screen. The activation position is dictated by a location of the fixed cursor. Finally, with the desired content sub-set in the activation position, the hand-held device is prompted to alter the content displayed on the display screen based upon reference to the desired content sub-set. With this methodology, the fixed cursor provides a convenient means for effectuating displayed content changes, such as zooming, linking, etc., while viewing a moving display.  
      Yet another aspect of the present invention relates to a hand-held display device including a display screen and a processor. The processor controls displays on the display screen. To this end, the processor is adapted to cause the display screen to display a fixed cursor. A displayed location of the fixed cursor is fixed relative to a border of the display screen. The processor is further adapted to cause the display screen to display moving content under the fixed cursor, whereby the moving content is zooming, panning, and/or tilting content. With this in mind, the processor is adapted to electronically monitor a relationship between the fixed cursor and the moving display content and alter the content displayed on the display screen based upon a content sub-set associated with the fixed cursor upon receiving a prompt to alter the content. With this configuration, the fixed cursor remains stationary relative to the display screen while displayed content is otherwise zoomed, panned, and/or tilted, allowing a user to easily act upon a desired content sub-set via the fixed cursor. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      Embodiments of the invention will be described with respect to the figures, in which like reference numerals denote like elements, and in which:  
       FIG. 1A  is a simplified, front view of a hand-held display device in accordance with one embodiment of the present invention;  
       FIG. 1B  is a block diagram of the hand-held display device of  FIG. 1A ;  
       FIGS. 2A-2E  illustrate, in simplified form, browsing of content on a hand-held device display screen;  
       FIG. 3  is a flow diagram illustrating one embodiment of a method for operating the display device of  FIG. 1A  to alter displayed content in accordance with the present invention;  
       FIG. 4  is a simplified view of an image captured by the hand-held display device of  FIG. 1A ;  
       FIGS. 5A and 5B  illustrate simplified captured user images for performing a zooming operation in accordance with the present invention;  
       FIGS. 6A and 6B  are screen displays illustrating a zooming operation corresponding with the user images of  FIGS. 5A and 5B ;  
       FIGS. 7A and 7B  illustrate simplified captured user images for performing a panning operation in accordance with the present invention;  
       FIGS. 8A and 8B  are screen displays illustrating a panning operation corresponding with the user images of  FIGS. 7A and 7B ;  
       FIGS. 9A and 9B  illustrate simplified captured user images for performing a tilting/scrolling operation in accordance with the present invention;  
       FIGS. 10A and 10B  are screen displays illustrating a tilting/scrolling operation corresponding with the user images of  FIGS. 9A and 9B ;  
       FIG. 11A  is a simplified, front view of a hand-held display device in accordance with another embodiment of the present invention;  
       FIG. 11B  is a block diagram of the hand-held display device of  FIG. 11A ; and  
       FIG. 11C  is a front view of the device of  FIG. 11A  with a fixed cursor removed from a display screen; and  
       FIGS. 12A-12E  illustrate use of the hand-held display device of  FIG. 11A . 
    
    
     DETAILED DESCRIPTION  
      I. Zoom/Pan/Tilt  
      One embodiment of the present invention relates to a hand-held display device  10  as shown in  FIGS. 1A and 1B . The hand-held display device  10  includes a housing  12 , a processor  14 , a display screen  16 , a camera system  18 , and a user input  20 . The various components are described in greater detail below. In general terms, however, the housing  12  maintains the processor  14 , the display screen  16 , the camera system  18 , and the user input  20 . The processor  14  is electronically connected to the display screen  16 , the camera system  18 , and the user input  20 . The camera system  18  includes a lens  22 . During use, the processor  14  operates to effectuate one or more browsing operations in which content displayed on the display screen  16  is altered via reference to images captured via the camera system  18 . In particular, the camera system  18  is operated to capture images of a user (not shown) otherwise handling the hand-held device  10 . Characteristic(s) of the captured images will vary from one another depending upon how the user positions and/or orients the hand-held device  10  relative to himself/herself. The processor  14  effectuates desired display content changes (e.g., browsing) based upon differences between the captured images.  
      In general terms, the hand-held device  10  can assume a wide variety of forms that otherwise incorporate a number of different operational features. For example, the hand-held device  10  can be a mobile phone, a hand-held camera, a portable computing device, etc. The necessary components and software for performing the desired operations associated with the designated end use is not necessarily shown in  FIGS. 1A and 1B , but are readily incorporated therein (e.g., input/output ports, wireless communication modules, etc.). Regardless, the display screen  16  is of a type known in the art, and content displayed thereon is dictated by the processor  14 . To this end, the processor  14  includes or is connected to a memory device. As is known in the art, this configuration allows the processor  14  to generate receive, store, and/or generate items, and prompt corresponding displays on the display screen  16  such as pictures, word processing documents, spreadsheets, characters, text, links, video, internet webpages, etc.  
      By way of reference, the display screen  16  is of a relatively small physical size, for example on the order of 2 inches×4 inches, and can incorporate a wide variety of technologies (e.g., pixel size, etc). Regardless of exact dimensions, the limited size of the display screen  16  renders displaying an entirety of a desired item difficult. By way of reference,  FIG. 2A  illustrates a hypothetical document  30  that a user (not shown) of the hand-held device  10  wishes to view on the display screen  16 . The document  30  consists of multiple characters generically illustrated as “A-H”. In order to be legible to the user, only a portion of the characters “A-H” can be displayed on the display screen  16  at any one time. A remainder of the document  30 , though not displayed on the display screen  16 , is stored in the memory of the hand-held device  10 . With this in mind,  FIG. 2A  schematically illustrates the display screen  16  displaying the characters “C” and “E”.  
      One possible browsing operation is generally referred to as “zoom” and entails increasing or decreasing a magnification level of the content displayed on the display screen  16 . For example,  FIG. 2B  illustrates a zoom operation in which the document  30  is effectively magnified by the processor  14 , such that the character “C” appears on the display screen  16  in enlarged form as compared to  FIG. 2A . Conversely,  FIG. 2C  illustrates a decreased zoom operation in which the document  30  is effectively reduced in size such that characters “C-F” are displayed on the display screen  16 .  
      An additional browsing operation is commonly referred to as “pan” and relates to horizontally moving or panning the document  30  across the display screen  16  in a left-to-right or right-to-left fashion. For example,  FIG. 2D  illustrates (as compared to  FIG. 2A ) a panning of the document  30  such that the display screen  16  displays the characters “D” and “F”.  
      Finally, an additional browsing feature is commonly referred to as “tilt” and relates to vertical moving, scrolling, or tilting the document  30  upwardly or downwardly across the display screen  16 . For example,  FIG. 2E  illustrates (relative to  FIG. 2A ) an upward tilt operation whereby the display screen  16  displays the characters “A” and “C”.  
      With the above conventions in mind, and returning to  FIGS. 1A and 1B , the hand-held device  10  performs one or more of the above-described browsing operations based solely upon images captured by the camera system  18 . The camera system  18  can assume a wide variety of forms (e.g., a CCD camera). Regardless of exact design, the camera system  18  includes the lens  22  that is otherwise positioned to facilitate obtaining images of a user (not shown) handling the hand-held device  10  and in particular, viewing or facing the display screen  16 . It will be recognized that many currently available hand-held display devices, as well as future products, already incorporate a camera system including a lens “facing” the user. These configurations are typically employed to capture an image of the user (or some other image desired by the user) and then display this image on the display screen  16  and/or store the image for subsequent transmission or reproduction on a separate device. As such, the physical component requirements associated with the hand-held device  10  of the present invention are currently available. However, currently available devices are unable to effectuate changes in content displayed on the display screen  16  via the captured images.  
      In particular,  FIG. 3  provides a flow diagram illustrating a method of operating the hand-held device  10 , in one embodiment performed by the processor  14 , for performing one or more of the above-described browsing functions. Beginning at step  40 , and with additional reference to  FIGS. 1A and 1B , a prompt is received from the user (not shown) to alter the content being displayed on the display screen  16  (e.g., a desired browsing function). To this end, the user input  20  can be employed to facilitate prompting of a desired browsing operation. The user input  20  can consist of a series of appropriately labeled touch keys (such as “zoom,” “pan,” and/or “tilt”). Alternatively, the user input  20  can be a voice recognition module, etc. Regardless, upon receiving a prompt for performing a desired browsing operation, at step  42 , a first image of the user is captured (“first user image”).  
      In one embodiment, the processor  14  activates or prompts the camera system  18  to obtain a current image of what is currently in the field of view of the lens  22 . By way of example,  FIG. 4  illustrates in highly simplified form one possible image I obtained upon activating or polling the camera system  18 . The camera system  18  has a fixed focal length as dictated by the lens  22 . This fixed focal length results in a constant or standard reference frame F for every image obtained via the camera system  18 . It is recognized that in most situations, the user (not shown) will be operating the hand-held device  10  in an environment having various background attributes. The exemplary image I of  FIG. 4  generically illustrates one such background environment. As a point of reference, then, the image I of  FIG. 4  can be described as a “user-in-environment image” that collectively includes an image of the user I U  and an image of all background subjects that are not otherwise the user (designated generally in  FIG. 4  as I E ). With these conventions in mind, in one embodiment, the present invention entails identifying the image of the user (or “user image”) I U  in the user-in-environment image I and/or distinguishing the user image I U  from the non-user portions I E  of the image I. Such image analyses techniques are currently employed in “blue screen” imaging techniques whereby software is provided that can readily identify prominent features associated with a human figure (e.g., algorithms directed to recognition of common curve segments corresponding to rounded or oval-shaped human head, neck, and/or shoulders). Alternatively, any other technique for identifying or distinguishing the user image I U  relative to the non-user image I E  of the user-in-environment image I can be employed. Once identified, the user image I U  can be parsed from the user-in-environment image I and a new image generated that includes the user image I U  against a “plain” background (e.g., a blue screen). Further, the user image I U  can be transformed into a mask image in which only the outline or perimeter of the user image I U  is provided. Regardless, a relationship between the user image I U  relative to the reference frame F is maintained.  
      Returning to  FIG. 3 , a second user image is captured at step  44 . The second user image can be captured at any point in time after capturing of the first user image at step  42 . Preferably, however, a short delay between image capturing occurs (on the order of 1 second, for example) providing the user (not shown) with sufficient time to move the hand-held device  10  ( FIG. 1 ) relative to the user, or vice-versa, so that the second user image “differs” from the first user image within the context of the reference frame F ( FIG. 4 ).  
      At step  46 , a spatial attribute of the first user image is compared with a corresponding spatial attribute of the second user image. The particular spatial attribute that is the subject of this comparison can take a variety of forms, and may vary depending upon a particular browsing function desired. Specific spatial attribute comparisons are described in greater detail below relative to desired browsing activities. In general terms, however, the spatial attribute of the user images relates to a feature of the user image I U  relative to the reference frame F as shown in  FIG. 4 . For example, the spatial attribute can be a relationship between a size or area of the user image I U  relative to an area of the reference frame F, a horizontal or vertical position of a center of the user image I U  relative to a designated edge of the reference frame F, a vertical and/or horizontal spacing between an identifiable perimeter point along the user image I U  relative to a designated edge of the reference frame F, etc. Regardless, the comparison performed at step  46  identifies a change or difference in the designated spatial attribute between the first and second user images I U .  
      The results of the above comparison are employed at step  48  to dictate a change or alteration in content displayed on the display screen  16 . Once again, this display alteration can be in the form of zooming on the content, panning the content, tilting or scrolling the content, etc. Further, the rate at which the display alteration progresses can be a function of the user image spatial feature comparison. Specific examples of display content alteration or browsing are provided below.  
      At step  50 , a determination is made as to whether the content alteration should continue (e.g., continue the zooming, panning, and/or tilting browsing operation). In one embodiment, reference is made to the user input  20  for making this determination. For example, where the user input  20  includes touch keys, the processor  14  can be adapted to continue a browsing operation so long as a designated key is continually pressed. Alternatively, other touch key operations (e.g., double depressing of a key) can signal that the user (not shown) desires to end a browsing operation.  
      If it is determined that the browsing operation should cease (“no” at step  50 ), the browsing method is stopped at step  52 . Conversely, where the browsing operation is to continue, the method returns to step  42  at which image(s) of the user are again captured and compared to one another to determine desired browsing functions. Alternatively, the selected browsing operation can simply continue until a request is received from the user (e.g., via the user input  20 ) to stop.  
       FIGS. 5A, 5B  and  6 A,  6 B illustrate one example of a zoom display content alteration based upon captured images in accordance with one embodiment of the present invention. By way of reference,  FIG. 5A  illustrates a first user image  60  captured by the hand-held display device  10  ( FIGS. 1A and 1B ), whereas  FIG. 5B  illustrates a second user image  62  captured at a later point in time. Once again, each of the user images  60 ,  62  are, in one embodiment, captured via the camera system  18  ( FIGS. 1A and 1B ) otherwise having a fixed focal length and/or has an adjustable focal length but is operated such that the focal lengths associated with the first and second user images  60 ,  62  are identical. Thus, each of the user images  60 ,  62  are set against the standard reference frame F inherent to the camera system  18  in  FIGS. 5A and 5B , respectively. The reference frame F provides a consistent reference point for comparing the user images  60 ,  62 . Though not shown, background image(s) may or may not be associated with the first and second user images  60 ,  62 .  
      A visual comparison of the first user image  60  ( FIG. 5A ) with the second user image  62  ( FIG. 5B ) reveals that the second user image  62  occupies a larger portion of the reference frame F. This is a result of the user (not shown) bringing the hand-held device  10  closer to the user&#39;s face and/or vice-versa. With this in mind, in one embodiment, an area of the first user image  60  is then determined or approximated, as is the area of the non-user portion within the reference frame F (designated generally at  64  in  FIG. 5A ). For example, an area of the reference frame F is known; with the determined or approximated area of the first user image  60  in mind, the area of the non-user portion  64  can be determined by simply subtracting the first user image  60  area from the reference frame F area. Regardless, a ratio of the first user image  60  area relative to the non-user portion  64  is then determined and designated as the spatial attribute of the first user image (step  46  in  FIG. 3 ). A similar relationship is established relative to the second user image  62  (it being noted that in  FIG. 5A , the non-user portion associated with the reference frame F/second user image  62  is designated generally at  66 ). A comparison of the ratios is then performed to dictate zooming and extent and/or rate of the zooming operation. For example,  FIG. 6A  illustrates an exemplary content  70  displayed on the display screen  16  prior to initiation of the zoom browsing operation. Subsequently, following the comparison of the corresponding spatial attributes of the first and second user images  60 ,  62 , the display screen  16  is prompted to enlarge the content  70  as shown in  FIG. 6B . Conversely, a reduction in content magnification can be achieved by moving the hand-held device  10  away from the user, such that the second user image  62  is “smaller” than the first user image. Alternatively, the areas of the first and second user image  60 ,  62  areas can be determined or approximated, and then compared to one another to determine extent and rate of zoom without reference to the non-user portion area  64  or  66 . That is to say, the compared, corresponding spatial attributes associated with the first and second user images  60 ,  62  can be the image areas or ratios based upon user image area and non-user image areas.  
       FIGS. 7A, 7B  and  8 A,  8 B illustrate one example of a pan display content alteration based upon captured images in accordance with one embodiment of the present invention.  FIG. 7A  illustrates a first captured user image  80  relative to the reference frame F, whereas  FIG. 7B  depicts a second captured user image  82  (captured after capturing the first user image  80 ) relative to the reference frame F. The difference between  FIGS. 7A and 7B  reflects the user (not shown) having maneuvered the hand-held device  10  ( FIG. 1 ) from left-to-right relative to the user&#39;s body (or vice-versa), such that the second captured user image  82  is in right-more position relative to the reference frame F as compared to the first user image  80  relative to the reference frame F.  
      In one embodiment, the pan browsing operation is effectuated by first determining or approximating a center C 1  (e.g., center of mass) of the first user image  80  using appropriate algorithms. A relationship between the center C 1  and a vertical side or edge of the reference frame F is then determined or approximated. For example, relative to  FIG. 7A , a distance D 1  between the center C 1  of the first user image  80  and a side S 1  of the reference frame F is determined or approximated. Similarly, with respect to  FIG. 7B , a center C 2  of the second user image  82  is determined or approximated, and a relationship between the center C 2  and the side S 1  of the reference frame F is made. For example, a distance D 2  between the center C 2  of the second user image  82  and the side S 1  of the reference frame F is determined. Alternatively, the centers C 1  and C 2  can be related to a side of the reference frame F other than the side S 1  (so long as the same, corresponding side is used as the basis for both user images  80 ,  82 ). The difference or shift between the corresponding spatial attributes is then made. For example, in one embodiment, D 1  is compared with D 2 . The amount or value of this difference or change is employed to effectuate a panning alteration in the content displayed on the display screen  16 . The comparison can dictate direction of pan, amount of pan, and/or rate of pan. To this end,  FIGS. 8A and 8B  illustrate example displayed content and correspond with  FIGS. 7A and 7B , respectively. Thus, the change in the first and second images  80 ,  82  relative to the reference frame F results in the display screen  16  having an altered display content from  FIG. 8A  to  8 B. A similar comparison can be made to effectuate a tilt or scroll browsing operation (with the spatial attributes otherwise forming the basis of the captured image comparison being a relationship between a user image center and a horizontal side or edge of the reference frame F).  
      An example of a tilt or scroll display content alteration performed on the basis of captured user images in accordance with one embodiment of the present invention is provided by  FIGS. 9A, 9B , and  10 A,  10 B.  FIG. 10A  illustrates a first user image  90  relative to the reference frame F, whereas  FIG. 10B  illustrates a second user image  92  (captured after capturing the first user image  90 ) relative to the reference frame F. As a point of reference, the difference between  FIGS. 9A and 9B  is indicative of the user (not shown) lowering the hand-held device  10  ( FIG. 1 ) relative to the user&#39;s head and/or “tilting” the hand-held device  10  relative to the user&#39;s head (i.e., to a top of the hand-held device  10  is moved away from the user&#39;s head while a bottom is moved toward the user&#39;s head. In either case, the second user image  92  appears “higher” relative to the reference frame F in  FIG. 9B  as compared to  FIG. 9A . A tilt or scroll browsing operation can be performed by first identifying a feature of the first user image  90  using appropriate algorithms. In one embodiment, the identifiable feature is a top of the user&#39;s head. Of course, a wide variety of other attributes can be identified, such as other features of the user&#39;s face and/or upper torso, eyes, ears, nose, etc. Regardless, a relationship between the identified feature and a horizontal side or edge S 2  of the reference frame F is determined or approximated to define a spatial attribute of the first user image  90 . For example, in one embodiment, a distance D 3  between a top of the first user image  90  and the side S 2  of the reference frame F is determined. Similarly, the same feature of the second user image  92  (e.g., top of the user&#39;s head) is identified and a relationship between the identified feature and the corresponding side S 2  of the reference frame F is obtained to define a spatial attribute of the second user image  92  corresponding with a spatial attribute of the first user image  90 . For example, a distance D 4  between the top of the second user image  92  and the side S 2  of the reference frame F is determined or approximated.  
      The corresponding spatial attributes (e.g., D 3  and D 4 ) are then compared to one another and used as the basis for dictating a desired change in the displayed content. For example,  FIGS. 10A and 10B  illustrate example displayed content and correspond with  FIGS. 9A and 9B , respectively. Thus, where the user tilts a top of the hand-held device  10  away from the user&#39;s face (not shown) and/or lowers the hand-held device  10 , thus effectuating the change from the first user image  90  to the second image user image  92  illustrated in  FIGS. 9A and 9B , the corresponding content displayed on the display screen tilts or scrolls from that shown in  FIG. 10A  to  10 B.  
      The desired browsing functions can be effectuated in manners varying from those associated with the above-described examples to possibly enhance user friendliness. In more general terms, however, altering content displayed on the display screen (e.g., zooming, panning, and/or tilting browsing functions) is accomplished without the use of a manual mouse or cursor, and does not require additional sensors. Instead, browsing operations are simply controlled by capturing and evaluating changes in user images. Complex calculations to determine precise distances between the user and the hand-held device, changes in orientation of the device relative to the earth, the speed at which the device is re-oriented relative to the user and/or the earth, etc., are not required.  
      The above-described image capture feature associated with the hand-held display device  10  can alternatively be employed to control operation of the device  10  based upon reference to a known image that is compared with the captured image, or based upon a level of “focus” of a sensed/captured image. For example, the device  10  can be adapted such that where the camera system  18  captures a particular image “known” to the processor  14  (e.g., by reference to an image database maintained by the processor; identifying certain features of the captured image; etc.), a particular activity will occur. In one embodiment, then, the hand-held device  10  is, or includes, a mobile phone. With this configuration, the processor  14  can be adapted such that when the camera system  18  captures an image recognized by the processor  14  to be indicative of a human ear (not shown), the processor  14  automatically transitions to a phone mode of operation. As such, the user is not required to perform any manual activities to initiate use of the hand-held device  10  as a phone other than bringing the hand-held device  10  near the user&#39;s ear. Of course, a wide variety of other operational modes can similarly be initiated based upon recognition of pre-designated image; once the processor  14  recognizes that the camera system  18  has captured or otherwise “viewed” the image in question (e.g., one or more fingers, fingers displayed in a particular orientation, etc.), the processor  14  automatically shifts to the designated operational mode.  
      Similarly, the above-described automatic transition to a particular mode of operation can be based upon a level of focus observed by the camera system  18 . In this regard, the processor  14  can be configured such that when the camera system  18  provides an image that cannot be focused, a pre-designated mode of operation is automatically initiated. For example, the pre-designated mode of operation can be a telephone mode of operation. Thus, with this configuration, as the hand-held device  10  is brought toward the user&#39;s ear/head, the camera system  18  will not be able to focus on the “image” due to the close proximity of the lens  22  to the user&#39;s ear/head. Under these circumstances, the processor  14  is programmed to automatically transition to a mobile phone mode of operation such that the user does not need to perform any manual inputting activities on the hand-held device  10  other than simply raising the hand-held device  10  toward his or her head. Again, a wide variety of other transitional modes can be implicated by an “out of focus” image.  
      Even further, the hand-held device  10  can be adapted to initiate a first mode of operation upon detecting an out of focus image, and a second mode of operation when a highly dark image is recognized, alone or in combination with a timing factor. For example, and as previously described, when the processor  14  determines that the image being captured by the camera system  18  cannot be focused, a telephone mode of operation is assumed. Subsequently, when a “no light” condition is sensed by the processor  14  via the camera system  18  (such as the user placing his/her thumb over the lens  22 ), a secondary mode of operation can be implemented by the processor  14 , such as operating the hand-held device  10  as a speakerphone. Once light is detected, the processor  14  then returns to the telephone mode of operation. Alternatively, a variety of other related modes of operation can be automatically implemented based upon the above-described “out of focus” and “lack of light” images/conditions.  
      In addition to controlling zoom/pan/tilt, the processor  14  can control other features of the hand-held device  10  based upon the captured image comparison technique described above. For example, the processor  14  can operate to control a brightness of the display screen  16  depending upon a change in location of the user&#39;s head (or other portion of the user) relative to the lens  22 . Similarly, display contrast, speaker volume, etc., can also be controlled. With these applications, the hand-held device  10  can further incorporate a separate user input whereby the user can inform the processor  14  that a desired feature control based upon proximity of the user&#39;s head to the hand-held device  10  is desired.  
      In alternative embodiments, the hand-held device is adapted to provide the user with the ability to select, set a “sensitivity” of the device  10  to motion and/or scale of movement. For example, a user may desire to effectuate zoom/pan/tilt (or other feature) control only when the user moves the hand-held device  10  in a relatively slow fashion, thus avoiding possible changes in zoom/pan/tilt (or other features) during normal use whereby the hand-held device  10  will naturally move slightly relative to the user when held in the user&#39;s hand. Similarly, the user may desire to effectuate zoom/pan/tilt (or other feature) control only in response to large-scale movements of the device  10  relative to the user (again, to avoid a situation where the device  10  naturally moves relatively slightly during normal use but when no change in display content is desired). To this end, the hand-held device  10  can provide a dedicated switch by which a user can alter the pre-programmed sensitivity level provided with the processor  14 . Regardless, the hand-held device  10  can provide a selected sensitivity or selectable sensitivity such that only large-scale and/or relatively slow movements effectuate zoom/pan/tilt changes, and smaller scale movements of the hand-held device  10  relative to the user are disregarded.  
      In another alternative embodiment, the hand-held device  10  employs a fingerprint identification imaging system as, or as part of, the camera system  18 . With this configuration, the processor  14  is adapted to recognize a fingerprint of the owner of the hand-held device  10  via biometric image analysis, such as by using a fingerprint identification pad as the lens  22 . For example, then, the hand-held device  10  can be configured such that it will only operate upon sensing (based on image analysis) the fingerprint of the assigned owner of the hand-held device  10 . Subsequently, the processor  14  performs pan and tilt control based upon an image analysis of motion or movement of the user&#39;s finger or thumb along/relative to the identification pad in a manner highly similar to the image analysis described above. With respect to zoom control, with this embodiment, a separate biometric finger/thumb identification pad can be provided apart from the fingerprint identification pad otherwise used to control pan/tilt, and specifically dedicated to effectuate zoom control. Depending upon the time a user places his or her finger over this dedicated pad, zoom can be increased or decreased. Alternatively, zoom can be controlled based upon left and right motion of the user&#39;s finger/thumb relative to the dedicated pad. Even further, the fingerprint identification image system can include a pressure gauge/sensor associated with the fingerprint imaging pad. Depending upon the sensed pressure (e.g., the force at which the user “presses” against the pad) zoom can be controlled. In either case, the fingerprint identification image capture pad can be integrated into the surface of a mouse-like pad otherwise provided with the hand-held device  10 , having a different texture as compared to a texture of the remainder of the mouse pad so that the user can easily identify the touch pad location for effectuating zoom/pan/tilt control.  
      II. Fixed Cursor  
      Another embodiment of a hand-held display device  100  in accordance with another embodiment of the present invention is shown in  FIGS. 11A and 11B . The device  100  includes a housing  102 , a processor  104 , a browsing module  106 , a display screen  108 , and a user input  110 . Details on the various components are provided below. In general terms, however, the housing  102  maintains the various components  104 - 110 . The processor  104  is electronically connected to the display screen  108  and the user input  110 . The browsing module  106  is also connected to, or portions are provided as part of, the processor  104 . The processor  104  dictates the display of content on the display screen  108 , with the browsing module  106  facilitating movement or browsing of displayed content. Further, the processor  104  is adapted to selectively display a fixed cursor  112  on the display screen  108 . During use, the fixed cursor  112  appears fixed on the display screen  108  relative to other content being simultaneously displayed and moved across the display screen  108 . Where desired, a sub-set of the displayed content can be readily associated with the fixed cursor  112  and acted upon as desired by a user (not shown).  
      The hand-held display device  100  can assume a wide variety of forms and incorporate a number of different components/features commensurate with a desired end-use. For example, the hand-held display device  100  can be akin to a mobile phone, portable computing device, camera, etc. Regardless, the display screen  108  is used to display desired content (e.g., word processing documents, forms, spreadsheets, images, internet webpages, etc.). Due to an inherently small physical size of the display screen  108 , it is often times necessary to display only portions of a particular item on the display screen  108 . With this in mind, the hand-held display device  100  is provided with the browsing module  106  that facilitates “browsing” content on the display screen  108 . The browsing module  106  can assume a wide variety of forms. In one embodiment, the browsing module  106  employs captured user images to effectuate desired browsing functions, such as that associated with the hand-held display device  10  previously described. Alternatively, a number of other browsing enablement techniques can be employed, such as conventional cursor movements, touch screens or keys, stylus interface, sensors and related algorithms (e.g., acceleration sensors), etc.  
      Regardless of how browsing of content displayed on the display screen  108  is facilitated, the processor  104  is adapted to establish and display the fixed cursor  112  during a browsing operation. The fixed cursor  112  can be permanently displayed on the display device  108 . Alternatively, the hand-held display device  100  can be adapted such that the fixed cursor  112  appears only when activated or requested by the user (not shown), such as via an appropriate touch key or voice module provided by the user input  110 . To facilitate a better understanding of the fixed cursor  112 ,  FIG. 11C  illustrates the hand-held display device  100  with the fixed cursor  112  ( FIG. 11A ) removed from the display screen  108 . While the fixed cursor  112  is illustrated in  FIG. 11A  as a “+”, a wide variety of other cursor designations, characters, and/or designs, are equally acceptable.  
      In addition to causing the display screen  108  to display the fixed cursor  112 , the processor  104  electronically monitors and maintains a relationship between a virtual representation of the fixed cursor  112  relative to a virtual representation of an item being displayed on the display screen  108 . For example, where the item being displayed on the display screen  108  is a spreadsheet, the processor  104 , maintains, such as via associated memory, an electronic version of the information from which the spreadsheet is generated. As portions of the spreadsheet are browsed or “moved” on the display screen  108 , the data representative of the particular content currently displayed “beneath” the displayed fixed cursor  112  is electronically managed and continuously “known” by the processor  104 .  
      With the above conventions in mind,  FIGS. 12A-12E  illustrate a method of using the hand-held display device  100  in accordance with one embodiment of the present invention. As a point of reference,  FIG. 12A  illustrates the display screen  108  as displaying content  120  along with the fixed cursor  112 . Once again, the content  120  can assume a wide variety of forms, and with the embodiment of  FIG. 12A  includes content sub-sets  122 ,  124 , and  126 . In most instances, the display screen  108  is displaying only a portion of a particular item stored by the processor  104  ( FIG. 11B ) such that a number of additional content sub-sets may be available for display on the display screen  108 , but are not otherwise currently displayed on the display screen  108 .  
      Browsing operation(s) are then initiated whereby the content displayed on the display screen  108  is altered or moved. For example, a pan browse operation can be utilized to transition the display screen  108  from the display of  FIG. 12A  to the display of  FIG. 12B . Each of the content sub-sets  122 - 126  has “shifted” to the left (relative to the orientation of  FIGS. 12A and 12B ) along the display screen  108 . An additional content sub-set  128  is now displayed on the display screen  108 . However, the fixed cursor  112  remains stationary or fixed relative to a border of the display screen  108  during this content movement.  
       FIG. 12C  represents a further transition or tilt/scroll operation in which the content  120  has moved horizontally along the display screen  108 . That is to say, each of the content sub-sets  122 - 128  has moved horizontally upwardly relative to the positions of  FIG. 12B . Once again, the fixed cursor remains stationary relative to the display screen  108  border. More particularly, the browsing operation has positioned the content sub-set  126  under the fixed cursor  112 . With the one embodiment of  FIG. 12C , the content sub-set  126  is an internet website address. Once the content has been “moved” along the display screen  108  (again, via a browsing operation provided by the browsing module  106  ( FIG. 11B )) “under” the fixed cursor  112  (or to some other location enabled by the fixed cursor  112 ), the content sub-set  126  can be acted upon by the hand-held display device  100 . For example, the user (not shown) can initiate a desired action, such as linking to the internet website address identified by the content sub-set  126 , by interfacing with the user input  110  ( FIG. 11A ). For example, a button can be depressed. Because the processor  104  continuously electronically monitors content data currently associated with the fixed cursor  112 , the processor  104  is thus able to perform the desired activity, such as changing the content displayed on the display screen  108  to illustrate the linked website/webpage (or a portion thereof) as shown in  FIG. 12D .  
      Another exemplary action or change in display facilitated by the fixed cursor  112  is provided by a comparison of  FIGS. 12B and 12E . In  FIG. 12B  the content  120  displayed on the display screen  108  has been browsed or moved such that the content sub-set  124  is “under” the fixed cursor  112 . Where desired by the user (not shown), the content sub-set  124  can be acted upon, for example performing a zoom operation resulting in the display shown in  FIG. 12E .  
      The hand-held display device  100  incorporating the fixed cursor  112  and related method of use provides distinct improvements over conventional hand-held display device browsing techniques. Unlike conventional approaches, the fixed cursor  112  does not “move” with movement of displayed content. To act upon a desired content sub-set, the user simply operates the hand-held display device  100  to position the desired content sub-set at or near the fixed cursor  112  for subsequent action thereon. This approach facilitates single-handed browsing and display changes by the user.  
      Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes can be made in form and detail without departing from the spirit and scope of the present invention.