Abstract:
A method is provided for displaying information from a distance on a monitor. By defining an image plane, the inventive system displays an area of focus of the plane on the monitor while storing the image in short-term memory. When the user selects a subsequent area of focus it is stored in short-term memory also, along with the first area of focus. The user is allowed to toggle between the stored images without having to recapture previously viewed information by retaining subsequent areas of focus in short-term memory. The user can discard, or delete, unwanted areas of focus or choose to move them to permanent memory. It is also possible to organize multiple areas of focus into groups or albums or save them individually.

Description:
FIELD OF INVENTION 
     This invention relates to electronic devices for aiding people with low vision. 
     BACKGROUND OF THE INVENTION 
     Low vision is a general term used to describe lowered visual acuity, and a specific legal term in Canada and the United States used to designate someone with vision of 20/70 or less in the better eye with correction. It can be a result of either congenital or acquired factors. An example of the former is Leber&#39;s congenital amaurosis and of the latter age related macular degeneration. 
     Some people with low vision can use their residual vision—their remaining sight—to complete daily tasks without relying on alternative methods. The role of a low vision specialist is to maximize the functional level of a patient&#39;s vision by optical or non-optical means. Primarily, this is by use of magnification in the form of telescopic systems for distance vision and optical or electronic magnification for near tasks. 
     Visually impaired patients may benefit from high-tech aids such as OCR scanners that can, in conjunction with text-to-speech software, read the contents of books and documents aloud via computer. Vendors also build closed-circuit televisions that electronically magnify paper, and even change its colour contract, for visually impaired users. 
     The vast majority of patients with low vision can be helped to function at a higher level with the use of low vision devices. Low vision specialists recommend appropriate low vision devices and counsel patients on how better to deal with their reduced vision in general. See, for example,  Computer Resources for People With Disabilities: A Guide to Assistive Technologies Tools and Resources for People of All Ages , Alliance for Technology Access, Hunter House, Inc. Publishers, 2004; and  In Sight: Guide to Design with Low Vision in Mind , Lucienne Roberts, Rotovision 2004 which are incorporated herein by reference. 
     The use of a CCTV or video magnifier is a simple way providing access to classrooms and public events to people with low vision. In the classroom setting, for example, printed material and objects displayed at the front of the room can be captured by a camera and the magnified image is displayed on a television screen or computer monitor. There are a large number of different types of models to choose from and they vary widely in the features offered. 
     For example, U.S. Pat. No. 6,731,326 to Bettinardi (which is incorporated herein by reference) describes a method of displaying information captured from a camera on a monitor. The camera captures an image and then allows the user to select a smaller portion for full, magnified, display. The &#39;326 patent also provides a method of allowing the user to pan the image and zoom in on a desired area. The user, however, must recapture information as he moves from portion to portion of the image. This takes additional time as well as requiring significant resources from the processor controlling the display. 
     Of the commercially available distance cameras, a problem arises where a user wishes to toggle through various areas in the camera&#39;s line of sight. Continuing with the classroom example; a user may wish to pan and zoom such as where a chalkboard contains a large amount of written information. Previous devices required a user to recapture information when a user desired to scroll back, perhaps to review some previous information. The need to recapture the image of the chalkboard creates a cumbersome interface, as well as wasting computer resources. 
     SUMMARY OF INVENTION 
     In a first embodiment, the invention includes an image display method utilizing an image capture device, a display in communication with the image capture device and an image memory in communication with the image capture device and display. The user defines an area of interest, either manually or through software developed to implement the invention, and then captures a plurality of images, or areas of focus, each image comprising at least a portion of the area of interest. The method stores the plurality of images in the image memory and establishes a location parameter associated with each image (to designate where the area of focus is located within the area of interest). The images are shown on the display, usually as a full image allowing the user to cycle through the images according to the location parameter associated with each image. 
     The user can further manipulate or alter each image or area of focus; such as changing magnification levels, orientation (rotation) and navigation. In some instances, such as when an area of focus is captured from a stored image of the area of interest rather than directly from the image capture device, the method provides the missing pixels in the magnified view using known interpolation techniques. 
     Although many location techniques are contemplated, one embodiment of the invention establishes the location parameter for each image using a Cartesian coordinate system whose increments are automatically determined by the resident software. Alternate embodiments, however, allow a user to manually determine location parameters. 
     The method also allows a user to display a live image of an area (such as the field of view or the areas of focus). The plurality of images are stored independently in image memory but can also be stored in an array for organization and efficient recall. All images in image memory can be stored to permanent (mass) memory without disrupting the user&#39;s access. 
     The invention also includes a device for implementing the previously describe method. The device includes a processor module, an image capture device communicatively coupled to the processor module, a monitor communicatively coupled to the processor module; and an image memory communicatively couple to the processor module. The image capture device is adapted to define an area of interest as well as to capture a plurality of images comprising an area of focus; the processor, however is also capable of capturing the areas of focus from a stored image of the area of interest. The processor module is also adapted to establish a location parameter to each are of focus regardless of how it is captured. The image memory is adapted to store the plurality of images captured by the image capture device or processor. The monitor displays each image, usually as a full image. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a fuller understanding of the invention, reference should be made to the following detailed description, taken in connection with the accompanying drawings, in which: 
         FIG. 1  is a block diagram of an illustrative architecture for employing the inventive method. 
         FIG. 2  illustrates how an area of interest is divided into multiple areas of focus. 
         FIG. 3  illustrates an enlarged area of focus selected from the area of interest and displayed on a screen. 
         FIG. 4  is a block diagram illustrating directional navigation of the areas of focus. 
         FIG. 5  illustrates an illustrative interface for displaying a menu of captured areas of focus. 
         FIG. 6  is a block diagram illustrating one embodiment of the invention. 
         FIG. 7  is a block diagram illustrating an alternate embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings, which form a part hereof, and within which are shown by way of illustration specific embodiments by which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the invention. 
     The instant invention, hereinafter “the invention,” includes a method of displaying graphic and textual information on an electronic screen to enhance visibility for persons with low vision or who are otherwise visually impaired. The invention employs the use of multiple, communicatively coupled hardware devices under the control of instructions from software designed to implement the invention. A general embodiment, shown in  FIG. 1 , uses image capture device  10 , monitor  20 , processing unit  30  and image memory  40 . An alternate embodiment also includes user input device  35  and mass memory  45 . 
     Image capture device  10  is commonly a distance camera, specifically designed for use by persons with low vision, but can be any imaging device capable of capturing an image of textual or graphic information. In a preferred embodiment, capture device  10  is coupled to the invention in a closed-circuit. The signal from capture device  10  is therefore transmitted to a predetermined number of users. The users are directly linked to image capture device  10 , although the link may include point-to-point wireless connections. An example of an embodiment employing a single capture device and multiple monitors is a classroom specifically equipped to accommodate a number of users with low vision. In this embodiment, wherein a single image capture device is shared, successive areas of focus are captured from an image of the entire area of interest. 
     Monitor  20  is any device that can display signals generated by image capture device  10  and processor  30 . While monitor  30  is most commonly a computer display (i.e. LCD, CRT), it can also include a portable device such as a PDA, or other wireless device, and a dedicated viewing device. 
     Processor  30  is any logic unit capable of running the software for implementing the invention. Processor  30  is connected to capture device  10 , monitor  20 , input device(s)  35 , image memory  40  and mass memory  45  through bus  12 . Processor  30  performs selected operations under the instructions of the corresponding operation program (the “software”). The software, in an illustrative embodiment, is stored in and selected from mass memory  45 . 
     Image memory  40  is, in an illustrative embodiment, a temporary storage location where images captured by image capture device  10  are stored. The images, representing the area of interest or multiple areas of focus, are stored in image memory prior to being saved in mass memory  45 , altered (i.e. magnified or rotated) by processor  30  or displayed by monitor  20 . Accordingly, a user can easily return to the original image saved in image memory  40  after the image is otherwise altered. Image memory  40  can be volatile (memory which is lost if power is disrupted) or nonvolatile memory. 
     Mass memory  45  is any device capable of storing, usually large amounts, information in a persistent and machine readable form. Examples of devices suitable for mass media  45  include, but are not limited to hard disks, floppy disks, drum memory, magentic tape, flash memory, optical disks, megneto-optical disks and holographic memory. Mass memory  45  does not include random access memory (RAM) or volatile memory. 
     In an illustrative embodiment, the invention permits a user to capture an area of interest, such as a blackboard or whiteboard in a classroom, through image capture device  10  for viewing on monitor  20 . The captured image can be magnified for easier viewing by the user. Moreover, the user can capture multiple images for magnification and viewing without losing previously captured images. Continuing with the example of a classroom setting, the user positions image capture device  10  to focus on the area of interest; namely the chalkboard, containing textual and graphic information, at the front of the room. The user can then capture specific subregions of the area of interest, or areas of focus, for viewing. 
     Referring now to  FIG. 2 , the user may decide to divide the chalkboard (area of interest  50 ) into quadrants (areas of focus  60 ). The user decides to capture quadrant I ( 60   a ), II ( 60   b ), III ( 60   c ) and IV ( 60   d ) successively. In this example, each area of focus (quadrant) is saved in image memory  40  independently for quick and easy recall by the user. The user can therefore bring up each area of focus for viewing, including magnification and navigation, without losing the remaining areas of focus. This frees the user from having to “re-capture” information. The user can easily cycle through images of the areas of focus saved in image memory. 
     In one embodiment, processor  30  establishes boundary parameters for area of interest  50 , using methods such as a Cartesian coordinate system. The boundary parameter is used to assign location values to points in the plane of the area interest, i.e. x-coordinates and y-coordinates. Coordinates are established by defining two perpendicular axis and assigning a unit length to each. The unit length assigned to each axis, as well as the points defining the x and y coordinates, are preferably determined by processor  30  but can also be defined by the user. The area of interest can be defined in numerous ways. The user can define the area of interest by adjusting the focus of image capture device  10 , or using a graphic interface to highlight, or crop, an image displayed on monitor  20 . 
     The invention also provides an embodiment wherein processor  30  electronically determines and captures multiple areas of focus after area of interest  50  has been defined by the user. In this example, processor  30  uses the boundary parameter to establish the multiple areas of focus, the size of which can be user defined (i.e. quadrants) or set by default. Each area of focus can be captured from an image of the entire area of focus or by a motorized device attached to the image capture device. An example of a suitable motorized device is described in U.S. Pat. No. 6,964,412 to Reed et al, which is incorporated herein by reference. 
     The area of interest can be stored in image memory  40  or saved to mass memory  45  prior to being displayed on monitor  20 . The area of interest can further be magnified, navigated or otherwise manipulated by processor  30  for direct viewing on monitor  20 . 
     Once the area of interest has been defined, and assigned boundary parameter values in some embodiments, areas of focus  60  can be captured. Area of focus  60  can be a subregion of area of interest  50  but in some cases, as discussed above, is the entire area of interest. In all cases, area of focus  60  comprises at least a portion of area of interest  50 . It is also possible for an area of focus to comprise all or some of another area of focus. 
     When area of focus  60  is established, processor  30  assigns an identification value to identify its location within the area of interest. In keeping with the illustrative embodiment above, the area of focus is assigned a location value based on the Cartesian coordinates corresponding to its location relative to the x and y axis of area of interest  50 . It is also possible, however, to assign other values based on parameters such as order-captured, quadrant, size, etc. Area of focus  60  is then displayed as a full image on monitor  20 , as shown in  FIG. 3 . The area of focus can be further magnified, navigated or otherwise manipulated by processor  30  during viewing on monitor  20 . It is also possible to save such an altered (manipulated) area of focus as displayed in either image memory  40  or mass memory  45 . 
       FIG. 4  illustrates one advantage of assigning a location value to each area of focus. Here it can be seen that providing a spatial identity to each area of focus makes it easier for a user to navigate individual areas of focus,  60   a  through  60   d , relative to the entire area of interest  50 . The user can be provided with directional navigation input options  70 , i.e. “left,” “right,” “up” and “down”, rather than (or in addition to) providing the user with common functions such as “next page” and “previous page.” 
     The invention provides the user with the ability to capture images of multiple areas of focus in temporary (image memory) and/or permanent memory (mass memory). Moreover the user can toggle between the plurality of images of the areas of focus in memory and/or a live image (passing directly from the camera to the monitor) without losing instant access to the saved images. Previously, the user was required to recapture the image after changing views. The interface also allows the user to remove unwanted images from image memory while keeping remaining images in the toggle cycle. 
     It is also possible, using the invention, to save images in image memory to mass memory without removing them from the toggle cycle. Images can be saved in mass memory as either individual images or in an array for convenient recall. Individual areas of focus can further be removed from the toggle cycle without disturbing the integrity or location parameter associated with the remaining images. Once an area of focus has been removed from the toggle cycle, processor  30  alters the toggle cycle to allow navigation to the next logical image when the user cycles through to where the deleted image would have otherwise been viewed. 
     By defining an area of focus, the user can zoom in on and navigate the textual and graphic information contained therein. The area of focus (or interest) is defined by adjusting the magnification of the camera or an image in image memory. Menus and/or key combinations switch views of consecutive areas of focus (left, right, up or down) as defined by the location parameter associated with each area of focus. This can be accomplished by accessing images in image memory or by providing live views of the area of focus and moving the camera with an associated motorized apparatus providing a smooth pan in the desired direction. Panning stops when reaching the boundary of the relevant area of focus or the area of interest. 
     In an alternate embodiment, the invention allows the user to alter the magnification of any area of interest  50 , or area of focus  60  and automatically adjusts the values for the remaining areas in turn. For example, the user establishes area of interest  50 , again a chalkboard, and captures the image thereof at 8× magnification. Processor  30  then establishes four areas of focus which are also captured at 8× magnification and displayed as full images. If the user then increases the magnification of area of focus  50  to 9×, processor  30  automatically adjusts the magnification level of the four established areas of focus to 9× magnification as well. Similarly, if the user increases or decreases the magnification of a particular area of focus, processor  30  automatically adjusts the magnification level of the remaining three areas of focus as well as the area of interest accordingly. This saves the user from having to continually adjust the magnification level for the successive views. 
     Once a plurality of areas of focus have been captured and stored, it may be beneficial to establish a catalog or a menu of areas of focus for viewing ( FIG. 5 ). This menu  80  can be kept in text form or thumbnail images  82  of the respective views. The user can then easily move between the different areas of focus without having to recapture or reload the images. It is also possible to establish an area of focus containing a live view of a preferred area  84 , or any subset thereof. From this interface it is possible to save the corresponding image to mass memory ( 86 ) or delete/close the image ( 88 ). Additional functionality is also added by coupling the stored images with optical character recognition (OCR) software  90  to allow text elements in the area of focus to be saved in files usable by word processors, or to be converted to a predetermined format  92  (i.e. .pdf) from the interface. 
     An alternate embodiment of the invention is shown in  FIG. 6 . In step  1 , the user zooms in on the viewing; thereby establishing the parameters of the area of interest. The user then zooms in on the area of interest to a desired magnification level, one that is comfortable for them to see the content within the area of interest, in step  2 . In step  3 , the processor automatically calculates the number of areas of focus needed to capture the information within the area of interest at the desired magnification level. For example, if the user does not zoom in after establishing the parameters of the area of interest, the number of areas of focus needed to capture the information is one (1). If, however, the user zooms into a magnification level of 8×, then additional areas of focus will be required. The number of areas of focus corresponding to an increase in magnification is the square of the magnification value. Therefore, if the area of interest is viewed at a magnification level of 8× then the number of areas of focus required is sixty four (64). 
     Once the necessary number of required areas of focus is calculated, each area of focus is displayed as a live image on the monitor (Step  4 ). In yet another embodiment, each area of focus is captured from an image of the entire area of focus or by a motorized device attached to the image capture device (discussed supra). 
     The user can navigate through the areas of focus using simple controls such as up, down, left and right. If the user moves to an area of focus which touches the boundary of the area of interest, subsequent commands to cycle in the direction of the outer parameter are ignored, as this would take the user outside the area of interest. Instead, the processor determines the next logical area of interest for display. 
     The user may determine that some areas of focus contain no useful information while they are in the process of navigation. In this case, the user can exclude unwanted areas of focus from the navigation cycle. Once an area of focus is marked for exclusion, it is skipped in the navigation cycle. When the user comes to a place in the navigation cycle where an area of focus has been removed, the processor determines the next logical area of interest for display. 
     In yet another embodiment, shown in  FIG. 7 , the areas of focus can be reestablished responsive to the user changing the magnification of any area of interest. For example, the user establishes an area of interest and selects a magnification level of 4×. The processor then determines that four (4) areas of magnification are required and displays them on the monitor. In step  1  of this embodiment, the areas of focus are shown at the original level of magnification. In step  2  the user changes the magnification level of one of the areas of focus to 8×. The processor, in step  3 , reestablishes the number of areas of focus necessary to cover the area of interest (which is 64, the square of the magnification level 8). The new areas of focus are then displayed at the new magnification level (8×) in step  4 . The user can also elect to exclude previously removed areas of focus from the new segmentation. 
     It will be seen that the advantages set forth above, and those made apparent from the foregoing description, are efficiently attained and since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matters contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. 
     It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall there between. Now that the invention has been described,