Abstract:
A method and apparatus for navigating a projected image. The method includes projecting, by a projector, an image on a surface, the projected image comprising a first portion of a virtual image. The method also includes determining a movement of the projector, and in response to the movement of the projector, changing the projected image by projecting a second portion of the virtual image different from the first portion.

Description:
TECHNICAL FIELD OF THE INVENTION 
     The present application relates generally to handheld projectors and, more specifically, to an apparatus and method for projector navigation based on movement of a handheld projector. 
     BACKGROUND OF THE INVENTION 
     A portable or handheld projector may be used to project illuminated images, such as photos, videos, or presentations, onto a display surface, such as a wall or display screen. A portable projector offers many of the same functions as larger tabletop projectors, and its reduced size makes it extremely transportable. Portable projectors that are small enough to fit in the palm of a hand are sometimes called pico projectors. In some cases, a portable projector is embodied in a wireless communication device, such as a smart phone. 
     SUMMARY OF THE INVENTION 
     A method of navigating a projected image is provided. The method includes projecting, by a projector, an image on a surface, the projected image comprising a first portion of a virtual image. The method also includes determining a movement of the projector, and in response to the movement of the projector, changing the projected image by projecting a second portion of the virtual image different from the first portion. 
     A device for navigating a projected image is provided. The device includes a projector configured to project an image on a surface, the projected image having a first portion of a virtual image. The device also includes one or more sensors configured to detect a movement of the device. The device further includes a processor configured, in response to the movement of the device, to control the projector to change the projected image by projecting a second portion of the virtual image different from the first portion. 
     A computer program product for navigating a projected image at a handheld projector is provided. The computer program product includes a tangible machine-readable medium encoded with computer-executable instructions that when executed cause the handheld projector to perform projecting an image on a surface, the projected image comprising a first portion of a virtual image. The handheld projector also performs determining a movement of the handheld projector. The handheld projector further performs, in response to the movement of the handheld projector, changing the projected image by projecting a second portion of the virtual image different from the first portion. 
     In some embodiments, the virtual image can be zoomed in and out to reveal more or less of the virtual image, by either movement of the projector, or by one of either software or hardware controls. 
     Before undertaking the DETAILED DESCRIPTION OF THE INVENTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like; and the term “controller” means any device, system or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware or software, or some combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts: 
         FIG. 1  illustrates a wireless device that includes a projector, according to one embodiment of the present disclosure; 
         FIG. 2  illustrates an operation of a handheld projector according to an embodiment of this disclosure; and 
         FIGS. 3 through 6  illustrate changes in a projected image due to movement of a projector, according to embodiments of this disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIGS. 1 through 6 , discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged handheld projector. 
     The present disclosure provides a system and method for navigating in images projected from a handheld projector, such as a projector incorporated into a wireless communication device. A typical handheld projector simply displays an image or sequence of images on a surface towards which the projector is oriented. Any interaction associated with the projected image, such as clicking on a hyperlink when the projected image is an image of a website, is typically accomplished via controls on the projector device itself or through other input devices, such as a remote control or keyboard and mouse. 
     If a typical handheld projector is physically moved, the projected image simply moves accordingly, resulting in no direct effect on user interface or navigation techniques. Thus, in order for a user to see and access all of the navigable menus or interface elements contained within a projected image, the entire image must be projected. For example, if a user wants to interact with a fairly complex interface, such as CNN&#39;s homepage, the user would have to project the image of the entire homepage in order to be able to view each navigable option. Due to optical constraints of many projectors, the projected image would need to be quite large in order to see the details and navigable parts of the homepage. This results in a very large projected image, requiring the user to have a fairly large surface to project on. 
     Alternatively, a user could project only a portion of the complex interface (e.g., only a portion of CNN&#39;s homepage). However, this would restrict the user&#39;s view of the interface, and limit the user to interact with only certain navigable options. 
     In accordance with this disclosure, a user could virtually lock down the projected image&#39;s position, and by physically moving the projector, reveal more information off-screen of the original image. By locking down the position, software may determine the movement and orientation of the projector and correspondingly offset the image, and make it appear as if the image were fixated on the surface. This gives the user the ability to reveal more of the image that is off-screen, by simply moving the projector. The user can return to the original view by simply moving the projector back in its original position. 
       FIG. 1  illustrates a wireless device that includes a projector, according to one embodiment of the present disclosure. Wireless device  100  comprises antenna  105 , radio frequency (RF) transceiver  110 , transmit (TX) processing circuitry  115 , microphone  120 , and receive (RX) processing circuitry  125 . Wireless device  100  also comprises speaker  130 , main processor  140 , input/output (I/O) interface (IF)  145 , keypad  150 , display  155 , projector  160 , and memory  165 . Wireless device  100  further comprises one or more navigational sensors, such as accelerometer sensor  170 , compass  175 , global positioning system (GPS) receiver  180 , and gyroscopic sensor  185 . 
     Radio frequency (RF) transceiver  110  receives from antenna  105  an incoming RF signal transmitted by a base station of a wireless network. Radio frequency (RF) transceiver  110  down-converts the incoming RF signal to produce an intermediate frequency (IF) or a baseband signal. The IF or baseband signal is sent to receiver (RX) processing circuitry  125 , which produces a processed baseband signal by filtering, digitizing the baseband or IF signal, additional filtering, if necessary, demodulation and/or decoding. Receiver (RX) processing circuitry  125  transmits the processed baseband signal to speaker  130  (i.e., voice data) or to main processor  140  for further processing (e.g., web browsing). 
     Transmitter (TX) processing circuitry  115  receives analog or digital voice data from microphone  120  or other outgoing baseband data (e.g., web data, e-mail, interactive video game data) from main processor  140 . Transmitter (TX) processing circuitry  115  encodes, modulates, multiplexes, and/or digitizes the outgoing baseband data to produce a processed baseband or IF signal. Radio frequency (RF) transceiver  110  receives the outgoing processed baseband or IF signal from transmitter (TX) processing circuitry  115 . Radio frequency (RF) transceiver  110  up-converts the baseband or IF signal to a radio frequency (RF) signal that is transmitted via antenna  105 . In accordance with embodiments of the present disclosure, RF transceiver  110 , processing circuitry  115  and  125 , and/or main processor  140  comprise a Wi-Fi module configured for Wi-Fi communication. 
     In certain embodiments, main processor  140  is a microprocessor or microcontroller. Memory  165  is coupled to main processor  140 . In certain embodiments, part of memory  165  comprises a random access memory (RAM) and another part of memory  165  comprises a non-volatile memory, such as Flash memory, which acts as a read-only memory (ROM). 
     Main processor  140  controls the overall operation of wireless device  100 . In one such operation, main processor  140  controls the reception of forward channel signals and the transmission of reverse channel signals by radio frequency (RF) transceiver  110 , receiver (RX) processing circuitry  125 , and transmitter (TX) processing circuitry  115 , in accordance with well-known principles. Main processor  140  executes software stored in memory  165  in order to control the overall operation of wireless device  100 . 
     Main processor  140  is capable of executing other processes and programs resident in memory  165 . Main processor  140  can move data into or out of memory  165 , as required by an executing process. Main processor  140  is also coupled to I/O interface  145 . I/O interface  145  provides wireless device  100  with the ability to connect to other devices such as laptop computers and handheld computers. I/O interface  145  is the communication path between these accessories and main controller  140 . 
     Main processor  140  is also coupled to keypad  150  and display unit  155 . The operator of wireless device  100  uses keypad  150  to enter data into wireless device  100 . Display  155  may be a liquid crystal display capable of rendering text and/or graphics from web sites. In certain embodiments, display  155  may be a touch-sensitive screen and keypad  150  may be displayed on the touch-sensitive screen of display  155 . Alternate embodiments may use other types of displays. 
     In accordance with embodiments of the present disclosure, main processor  140  is coupled to projector  160  and one or more navigational sensors, such as accelerometer sensor  170 , compass  175 , global positioning system (GPS) receiver  180 , and gyroscopic sensor  185 . Projector  160  is capable of projecting an illuminated image onto a display surface. Compass  175  may be, for example, a  3 D magnetic compass. Accelerometer  170 , compass  175 , GPS receiver  180 , and gyroscopic sensor  185  enable wireless device  100  to determine location and orientation information, as described in greater detail herein. In certain embodiments, wireless device  100  may include one, more than one, or all of the navigational sensors. Signals received from the navigational sensors are used to control projector  160  and the display of images from projector  160 . 
     Although  FIG. 1  illustrates one example of wireless device  100 , various changes may be made to  FIG. 1 . For example, wireless device  100  may represent a dedicated handheld projector that is not capable of sending or receiving voice or data communication over a wireless network. Such a projector may not include every component shown in  FIG. 1 , such as processing circuitry  115 ,  125  and RF transceiver  110 . Also, the configuration shown in  FIG. 1  is for illustration only. Various components could be combined, subdivided, or omitted and additional components could be added according to particular needs. In addition, functions described as being performed by one component of wireless device  100  could be performed by any other suitable component(s) of wireless device  100 . 
     When a handheld projector or a device with a projector displays an image on a surface, the useful image size is limited by the optical capabilities of the projector and the position and eyesight of the viewer. If the projected image is made relatively large (e.g., by moving the projector further from the display surface), the projected image may become fuzzy or too dim. If the projected image is made relatively small (e.g., by moving the projector closer to the display surface), the projected image may be too small to read from a distance. In some embodiments, a display size measuring approximately two feet on the diagonal provides a sharp, well-illuminated image that is readable by several viewers in a space such as a small conference room. However, this size is merely one example. Other projectors may be capable of projecting readable images having smaller or larger sizes. 
     The size of the projected image limits the amount of information that can be conveyed. As an example, suppose a user wants to display a map of Texas. The map is relatively detailed, showing large cities and many smaller cities and towns, with their names and perhaps other information. If the user projects the entire map of Texas, very little (if any) of the text of the map can be read on the projected image, due to the optical constraints of the projector to display so much text in a space the size of the projected image. To make the text readable, a user could zoom into a smaller area of the map (e.g., the Dallas-Fort Worth region), but areas of Texas outside the zoomed area (e.g., Austin, El Paso) are no longer part of the projected image. 
     This zoomed position (“virtual position”) can be locked, using a control or software input on the projector. The control may be a soft key on the projector&#39;s screen or a hardware key on the projector. 
     As the projector moves, the projected image moves on the display surface. As the projected image moves, the project image also changes to reveal content of the whole image (e.g., the map of Texas) that is beyond the edges of the zoomed image (e.g., the Dallas-Fort Worth region). For example, as the projector tilts downward, the projected image moves downward and begins to reveal parts of Texas below Dallas-Fort Worth (e.g., Austin may come into view on the projected image). 
       FIG. 2  illustrates an operation of a handheld projector according to an embodiment of this disclosure. For ease of explanation, handheld projector  200  may represent wireless device  100  of  FIG. 1 . However, other embodiments of handheld projector  200  may be used without departing from the scope of this disclosure. 
     As shown in  FIG. 2 , handheld projector  200  includes a display  205  and a projection unit  207 . In an embodiment, display  205  may represent display  155 , and projection unit  207  may represent projector  160 . Display  205  displays an image, such as a website, a slide in a presentation, a report, or any other suitable text or graphic image. In an embodiment, display  205  may also display one or more controls, such as soft keys, configured to control one or more settings or operations of handheld projector  200 . 
     Projection unit  207  of handheld projector  200  is activated and projects an image  210  onto a surface, such as a wall or display screen. Projected image  210  reveals a portion of a larger image that includes text  220  and graphic  230 . The larger image may be a website, a slide in a presentation, a report, or any other suitable image containing text or graphics. The larger image is a virtual image, in that the portions of the larger image outside of projected image  210  are not currently displayed on the display surface. 
     For example, as shown in  FIG. 2 , projected image  210  includes the “XT” in “TEXT” in text  220  and the left half of the square in graphic  230 . The “TE” in “TEXT” in text  220  and the right half of the square in graphic  230  are currently “hidden”, i.e., not displayed on the display surface, and are represented with dotted lines in  FIG. 2  only to illustrate the content of the larger image. As projector  200  is moved (e.g., rotated right or left), other portions of the larger image, including currently hidden portions of text  220  or graphic  230 , may be revealed in the projected image  210 . The movement of projector  200  is detected by one or more sensors in projector  200 . Signals from the sensors related to the movement are processed in projector  200  and cause a change in the projected image from projection unit  207 . This is described in greater detail below. 
     Display  205  may display a number of different images. In one embodiment, the image on display  205  is a replica or mirror of projected image  210 . In other words, display  205  displays substantially the same image as is shown in projected image  210 . As projected image  210  changes (e.g., due to movement of projector  200 ), the image in display  205  also changes. 
     In another embodiment, the image on display  205  is the larger image (i.e., the whole image including all of text  220  and graphic  230 ), of which projected image  210  shows only a portion and reveals other portions upon movement of projector  200 . In this embodiment, although the projected image  210  may change to reveal previously hidden portions of the larger image (e.g., due to movement of projector  200 ), the image on display  205  remains the same. 
     In another embodiment, the image on display  205  is another image that is unrelated to projected image  210 . For example, the image on display  205  may include one or more soft keys that control projection unit  207 . As a particular example, if projected image  210  is a slide show of family photos on a wall, the image on display  205  may include thumbnails of the photos, or slide show controls, such as Next, Previous, Play Slideshow, Zoom in/out, Music, and so forth. As another example, if projected image  210  is a video (e.g., a movie), the image on display  205  may include video controls, such as Play, Fast Forward, Review/Rewind, Stop, and so forth. 
     Although  FIG. 2  illustrates one example of handheld projector  200 , various changes may be made to  FIG. 2 . For example, various components of handheld projector  200  could be combined, subdivided, or omitted and additional components could be added according to particular needs. In addition, functions described as being performed by one component of handheld projector  200  could be performed by any other suitable component(s) of handheld projector  200 . 
       FIGS. 3 through 6  illustrate changes in a projected image due to movement of a projector, according to embodiments of this disclosure. 
       FIG. 3  illustrates handheld projector  200  with projection unit  207  deactivated. Display  205  displays an image, such as a website, a slide in a presentation, a report, or any other suitable text or graphic image. In an embodiment, display  205  may also display one or more controls, such as soft keys, configured to control one or more settings or operations of handheld projector  200 . 
       FIG. 4  illustrates handheld projector  200  with projection unit  207  activated, such as shown in  FIG. 2 . Projected image  210  displays a portion of a larger image that includes text  220  and graphic  230 . Display  205  is not shown with an image in  FIG. 4 , however it will be understood that display  205  could display any suitable image, as described earlier. 
     Handheld projector  200  uses sensors to detect the position and movement of projector  200 . The sensors may include one or more of the navigational sensors described in  FIG. 1 , such as accelerometer sensor  170 , compass  175 , global positioning system (GPS) receiver  180 , and gyroscopic sensor  185 . 
     In an embodiment, handheld projector  200  uses compass  175  and accelerometer sensor  170  to determine the location and orientation of projector  200 . Using readings from accelerometer  170 , along with a low pass filter associated with the accelerometer  170 , projector  200  calculates the direction of gravity. Handheld projector  200  uses digital compass  175  in conjunction with accelerometer  170  to detect the direction that projector  200  is facing. As projector  200  moves, it uses compass  175  and accelerometer sensor  170  to detect changes in location, orientation, and direction of movement, as well as speed of movement. Handheld projector  200  may also use GPS receiver  180  or gyroscope  185  to detect changes in location, orientation, and direction of movement, as well as speed of movement. 
       FIG. 5  illustrates handheld projector  200  after a rotational movement in one direction. As shown in  FIG. 5 , handheld projector  200  has been moved from its position shown in  FIG. 4 . Specifically, handheld projector  200  has been rotated several degrees to the right. As described above, one or more sensors in handheld projector  200  detect the movement. Signals from the one or more sensors indicating the magnitude, direction, speed, or timing of the movement are transmitted to a processor, such as main processor  140 . The processor receives the signals and, based on the movement indicated by the signals, causes the projection unit  207  to display a different projected image  210 . For example, projected image  210  shifts to the right on the display surface, due to the rotation of projector  200 . In addition, the image displayed in projected image  210  also shifts to the right with respect to the larger virtual image. The change in display in projected image  210  is substantially synchronized with the movement of projector  200 . In other words, as projector  200  moves, projected image  210  changes at the same time and at the same rate. More specifically, as projector  200  rotates to the right, hidden portions of graphic  230  are gradually revealed in projected image  210 , while visible portions of text  220  are gradually concealed. As shown in  FIG. 5 , projected image  210  now includes all of graphic  230  and none of text  220 . 
       FIG. 6  illustrates handheld projector  200  after a rotational movement in another direction. As shown in  FIG. 6 , handheld projector  200  has been moved from its position shown in  FIG. 5 . Specifically, handheld projector  200  has been rotated several degrees to the left. Again, one or more sensors in handheld projector  200  detect the movement. Signals from the one or more sensors indicating the magnitude, direction, speed, or timing of the movement are transmitted to the processor, such as main processor  140 . The processor receives the signals and, based on the movement indicated by the signals, causes the projection unit  207  to display a different projected image  210 . Here, projected image  210  shifts back to the left on the display surface, due to the rotation of projector  200 . In addition, the image displayed in projected image  210  also shifts to the left with respect to the larger virtual image. As shown in  FIG. 6 , projected image  210  now includes all of text  220  and none of graphic  230 . 
     Although  FIGS. 3-6  illustrate examples of changes in projected image  210  due to movement of projector  200 , various changes may be made to  FIGS. 3-6 . For example, although projector  200  is described as being rotated left and right, projector  200  is capable of detecting other movements as well. As a specific example, projector  200  may detect rotational movement up or down (i.e., “pitch”), twisting rotational movement (i.e., “roll”), or translational movement in any direction. Projector  200  is capable of updating projected image  210  in response to any of these movements. As another example, the virtual image may be zoomed in and out to reveal more or less of the virtual image, by either movement of projector  200 , or by one of either software or hardware controls. 
     Although the present disclosure has been described with an exemplary embodiment, various changes and modifications may be suggested to one skilled in the art. It is intended that the present disclosure encompass such changes and modifications as fall within the scope of the appended claims.