Abstract:
A combination mobile terminal and camera with multiple light apertures in the housing. One aperture is disposed on a front side of the housing while another aperture is disposed on a rear side of the housing. The device has an image sensor disposed within the housing for converting images formed by light directed onto the image sensor into electrical signals. The device also has a movable optical system for selectively directing light passing through one of the light apertures onto the image sensor. The device also includes an image processor coupled to an output of the image sensor for processing the electrical signals from the image sensor to produce image signals. The device also has a position detector to detect the position of the movable optics and for directing the image processor to invert the images as needed.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates generally to camera devices and, more particularly, to a camera device having first and second selectable image paths. 
   Camera phones, which comprise a mobile, hand-held telephone and a digital camera in the same physical package, have recently been introduced to the market. At present, the development of digital camera phones is in its infancy. Wideband Code Division Multiple Access (WCDMA) and other emerging technologies will soon make it possible to send digital images and live video over wireless communication networks. These emerging technologies will spawn a new breed of camera phones that can be used for teleconferencing or for recording video that can be transmitted over the wireless communications network. 
   When recording video, the user generally likes to see the image being recorded. In modern video cameras, the image seen through the lens of the camera is presented on a liquid crystal display. The display is typically oriented to face the opposite direction of the lens so that the user can use the display as a viewfinder to view the image being recorded. However, when the user is participating in a video conference, a display facing in the same direction as the lens is needed so that the user can see the other parties while transmitting the user&#39;s own image. Modern video cameras solve this problem by mounting the display on a swivel so that it can be rotated to face in either direction. While it is technically feasible to make a display for a camera phone that can swivel, that is not a very practical solution for a camera phone. Color displays have numerous connections that would require use of a flexible connector. If a flexible connector is used, the display would need to swivel in one direction to move from position A to position B, and in the opposite direction to move back from position B to position A. Also the design of the flex is difficult to implement and is often unreliable. 
   SUMMARY OF THE INVENTION 
   The present invention relates to camera devices, such as a digital camera or camera phone, having first and second selectable image paths. The camera device comprises a housing having a first light aperture formed in a front side of the housing and a second light aperture formed in the back side of the housing. An image sensor is disposed within the housing for converting images formed by light on the image sensor into raw image data. The raw image data is processed by an image processor to produce formatted image signals for output to a display or for transmission by a transceiver. An optical system selectively directs light along either the first or second image paths onto the image sensor. In an exemplary embodiment, the optical system comprises a rotatable or slidable mirror assembly. When the rotatable mirror assembly is in a first position, light entering housing through the first light aperture is directed along the first image path to the image sensor. When the mirror assembly is in the second position, light entering through the second light aperture is directed along a second image path to the image sensor. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a block diagram of an exemplary camera device according to the present invention. 
       FIG. 2  is a perspective view of the camera device as seen from the front. 
       FIG. 3  is a perspective view of the camera device as seen from the back. 
       FIG. 4  is a perspective view showing one embodiment of a mirror assembly used in the camera device. 
       FIGS. 5 and 6  are schematic illustrations showing the mirror assembly in the forward-looking and rearward-looking positions respectively. 
       FIG. 7  is a perspective view showing an alternate embodiment of the mirror assembly including a lens cover. 
       FIGS. 8 and 9  are schematic diagrams showing variation of the first embodiment of the camera device with two fixed lenses. 
       FIG. 10  is a perspective view showing a second exemplary embodiment of the camera device. 
       FIG. 11  is a perspective view showing the mirror assembly used in the second embodiment of the camera device. 
       FIG. 12  is a perspective view showing a third exemplary embodiment of the camera device. 
       FIG. 13  is a perspective view showing the mirror assembly used in the third embodiment of the camera device. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1  is a block diagram of an exemplary camera device indicated generally by the numeral  10 . The exemplary embodiment of the camera device comprises a camera phone, which is used as an example to describe one application of the invention. The present invention is not, however, limited to a camera phone. The present invention may be embodied in other camera devices including without limitation a digital camera, a mobile terminal, or other devices incorporating a camera. Mobile terminals may include cellular radiotelephones, personal communication services (PCS) devices, personal digital assistants (PDAs), laptop computers, and palm-top computers. 
   The camera phone  10  comprises a microprocessor  12 , program memory  14 , input/output circuit  16 , transceiver  18 , audio processing circuit  20 , user interface  22 , image sensor  32 , image processor  34 , and optical system  50 . Microprocessor  12  controls the operation of the camera phone  10  according to programs stored in program memory  14 . Input/output circuits  16  interface the microprocessor  12  with the user interface  22 , transceiver  18 , audio processing circuit  20 , and image processing circuit  34 . User interface  22  comprises a keypad  24 , display  26 , microphone  28 , and speaker  30 . Keypad  24  allows the operator to dial numbers, enter commands, and select options. The display  26  allows the operator to see dialed digits, call status, and other service information. Microphone  28  converts the user&#39;s speech into electrical audio signals, and speaker  30  converts audio signals into audible signals that can be heard by the user. Audio processing circuit  20  provides basic analog output signals to the speaker  30  and accept analog audio inputs from the microphone  28 . Transceiver  18  is coupled to an antenna  36  for receiving and transmitting signals. 
   Image sensor  32  captures images formed by light impacting on the surface of the image sensor  32 . The image sensor  32  may be any conventional image sensor  32 , such as a charge-coupled device (CCD) or complementary metal oxide semiconductor (CMOS) image sensor. Image processor  34  processes raw image data collected by the image sensor  32  for subsequent output to the display  26  or for transmission by the transceiver  18 . The image processor  34  is a conventional signal microprocessor programmed to process image data, which is well known in the art. 
     FIGS. 2 and 3  are perspective views illustrating an exemplary embodiment of the camera phone  10 . The camera phone  10  includes a housing  40 , which in the disclosed exemplary embodiment has a front cover  42  and a back cover  44 . The keypad  24 , display  26 , microphone  28 , and speaker  30  are disposed in the front cover  42 . The front cover  42  further includes a first light aperture  46  disposed above the display  26 , which faces in the same direction as the display  26 . Back cover  44  includes a second light aperture  48 , which faces in the opposite direction of the display  26 . As will be described more fully below, the first and second light apertures  46 ,  48  allow the camera phone to look forwardly, e.g. the same direction as the display  26 , or rearwardly, e.g. the opposite direction of the display  26 . 
   Contained within housing  40  is a printed circuit board  38  which contains the electronic components of the camera phone  10  such as the microprocessor  12 , memory  14 , I/O circuits  16 , transceiver  18 , audio processing circuit  20 , and image processing circuit  34 . Image sensor  32  is also typically mounted to printed circuit board  38 . 
     FIG. 4  is a perspective view illustrating the optical system  50  in the exemplary embodiment. The function of the optical system  50  is to selectively direct light along either a first image path or a second image path to the image sensor  32 . The optical system  50  comprises an objective lens  54 , a double-sided movable mirror  56 , and a stationary mirror  58 . The objective lens  54  and movable mirror  56  are part of a rotating mirror assembly  52 . Mirror assembly  52  includes, in addition to the objective lens  54  and movable mirror  56 , a spherical housing  60  mounted on a shaft  62 . A ring  64  is disposed on the outer end of the shaft  62 , which extends through the housing  40 . Ring  64  provides a means for the user to rotate the mirror assembly  52 . Those skilled in the art will recognize that the element for rotating the mirror assembly  52  may be located in the front, back, or sides of housing  40  and that a variety of different elements could be used. Mirror assembly  52  is held by a spring clip  67  that engages a pair of flat surfaces  68  on shaft  62  of the mirror assembly  52 . The flat surfaces  68  function as an index mechanism to yieldably station the mirror assembly  52  at the forward-looking and rearward-looking positions as described more fully below. 
   Spherical housing  60  of mirror assembly  52  contains a cavity  66  having two openings—an entry opening  70  and exit opening  72 . The axis of entry opening  70  is disposed perpendicular to the axis of shaft  62  so that the orientation of entry opening  70  changes when shaft  62  is rotated. The axis of exit opening  72  is coincident or parallel to the axis of shaft  62  so that exit opening  72  remains oriented in the same direction regardless of the angular position of shaft  62 . Objective lens  54  is mounted within or adjacent the entry opening  70 . Movable mirror  56  is positioned within cavity  66  so that light entering through entry opening  70  is reflected out through exit opening  72 . Light reflected out of the mirror assembly  52  is then reflected by stationary mirror  58  onto the surface of the image sensor  32 , which is mounted to the printed circuit board  38 . 
   The rotating mirror assembly  52  allows the objective lens  54  and movable mirror  56  to move between at least first and second positions. Equivalently, the objective lens  54  and movable mirror  56  could be mounted for sliding movement between first and second positions. In the first position, shown in  FIG. 5 , light entering through the first light aperture  46  is directed along a first image path to the image sensor  32 . In the second position, shown in  FIG. 6 , light entering through the second light aperture  48  is directed along a second image path to the image sensor  32 . 
     FIGS. 5 and 6  are schematic illustrations showing the operational positions of the mirror assembly  52 . Light from an object is directed along either a first or second image path depending on the position of mirror assembly  52 . Image sensor  32  picks up the reflected light and converts the reflected light to raw image data. The raw image data is processed by image processor  34  to provide an image signal which can be formatted for output to the display  26  or for transmission by the transceiver  18 . 
     FIG. 5  illustrates the mirror assembly  52  in the forward-looking position. Light enters the housing  40  (not shown in  FIGS. 5 and 6 ) through the first light aperture  46  and passes through the objective lens  54 . Movable mirror  56  reflects the light through the exit opening  72  in the lens housing  60  in the direction of the stationary mirror  58 . Stationary mirror  58  reflects light exiting lens housing  60  onto the image sensor  32 . The path illustrated in  FIG. 5  is referred to herein as the first image path. 
   In  FIG. 6 , the mirror assembly  52  is rotated 180° from the position shown in  FIG. 5  to the rearward-looking position. In this position, light enters housing  40  through the second light aperture  48 , passes through the objective lens  54 , is reflected by movable mirror  56  through exit opening  72 , and finally is reflected by stationary mirror  58  onto the image sensor  32 . In this case, the image formed on the image sensor  32  will be inverted as compared to the image formed when the mirror assembly  52  is in the forward-looking position. A position sensor  80  detects the position of the mirror assembly  52  and generates a position signal that is input to the image processor  34 . Based on the input from the position sensor  80 , the image processor  34  inverts image so that the displayed image is correct. 
   A variety of different techniques can be used to detect the position of the mirror assembly  52 . In the exemplary embodiment of  FIG. 4 , the position sensor  80  comprises a wiper contact  82  disposed on the shaft  62  of the mirror assembly  52 . When the mirror assembly  52  is rotated to the rearward-looking position, the wiper contact  82  on the shaft  62  makes an electrical connection between two spaced-apart contacts  84  on the printed circuit board  38  and causes a signal to be generated indicative of the position of the mirror assembly  52 . In this example, the signal is a voltage signal. Those skilled in the art will recognize that many other ways exist to detect position of the mirror assembly  52 . Instead of a wiper contact  82 , a mechanical switch actuated by rotation of the mirror assembly  52  could be used to determine the position of the mirror assembly  52 . Also, there are many different types of non-contact position sensors  80  that can be used to detect the position of the mirror assembly  52 , including capacitance sensors, inductance sensors, Hall-effect sensors, magnetic sensors, and optical sensors. 
   The camera phone  10  of the present invention can be used for video conferencing or as a conventional video camera. For teleconferencing, the mirror assembly  52  is oriented so that the lens faces forward, i.e., in the same direction as the display  26 . In this orientation, the user&#39;s image is transmitted while the user talks on the camera phone  10 . At the same time, the user can view the image being transmitted from the person at the other end of the call. To use the camera phone  10  as a video camera, the mirror assembly  52  is rotated to the rearward-looking position, i.e., facing away from the display  26 . In this position, the user can use the camera phone  10  to record video images while using the display  26  as a viewfinder. In a preferred embodiment, a button  86  on the camera phone  10  allows the user to turn imaging system on and off. 
     FIG. 7  shows an alternate embodiment of the mirror assembly  52 . The embodiment shown in  FIG. 7  is identical to the embodiment of  FIG. 4  but with the addition of a lens cover  90 . Lens cover  90  serves to cover the objective lens  54  when not in use. Lens cover  90  is semi-spherical in form and conforms to the outer surface of spherical housing  60 . A small pin  92  extends outward from the spherical housing  60 . When the objective lens  54  is not in use, the mirror assembly  52  is rotated so that the objective lens  54  is covered by lens cover  90 . The lens cover  90  can be rotated to cover either the first light aperture  46  or second light aperture  48 . In  FIG. 7 , the lens cover  90  is covering the second light aperture  48 . To move the lens cover  90  so as to conceal the first light aperture  46 , the user rotates the mirror assembly  52  in either direction until pin  92  engages the edge of lens cover  90  and then continues to rotate the mirror assembly  52 . Once pin  92  engages the lens cover  90 , the lens cover  90  rotates with the remainder of the mirror assembly  52 . The same procedure is followed to rotate the lens cover  90  back to the position shown in  FIG. 7 . 
   As an alternative to a rotating lens cover  90 , the housing  40  of the camera phone  10  may include movable shutters or other covers. Also, a separate lens cover  90  or shutter can be eliminated by proper sizing of the entry opening  70 . In this case, the mirror assembly  52  could be rotated such that the objective lens  54  faces sideways and the spherical housing  60  closes both light apertures  46  and  48 . 
   Those skilled in the art will appreciate that many other arrangements of lenses and mirrors are possible for carrying out the present invention. For example, the objective lens  54  in the mirror assembly  52  can be replaced by two stationary objective lenses  54 ′—one for each light aperture  46 ,  48 —as shown in  FIGS. 8 and 9 . In this variant of the invention, the stationary lenses  54 ′ are fixed. Additional lenses or mirrors could also be used. For example, a focusing lens or special effects lens could be included in the first or second image paths. Also, by positioning the image sensor  32  along the axis of the exit opening  72  of the mirror assembly  52 , the stationary mirror  58  could be eliminated. In another variation, the objective lens  54  could be movable between at least first and second positions while using stationary reflecting mirrors. 
   It is also possible to replace the movable mirror  56  with a series of stationary mirrors and liquid crystal light valves as are commonly used in projection systems. The light valves could be used to selectively block or transmit light entering through the first and second light apertures by applying a voltage to the light valve which alters the transmission characteristics of the light valve. This would increase the total number of parts while eliminating movable parts. The light valves could be activated by a switch or button on the camera phone  10 . 
   Thus, the particular arrangement of mirrors and lenses disclosed herein should not be construed as limiting the invention. The invention encompasses any arrangement of mirrors, lenses, light valves, or other components which allow light to be selectively directed along a plurality of image paths to an image sensor. 
     FIG. 10  is a perspective view illustrating a second embodiment of the camera phone  10  of the present invention. The camera phone  10  of  FIG. 10  is similar to the embodiment of  FIGS. 1–9  and, therefore, similar reference numbers are used to indicate similar parts. In the embodiment shown in  FIG. 10 , a dial  65  is disposed in the front cover  42  of the camera phone  10 . Dial  65  is part of a mirror assembly  52 ′ shown in  FIG. 11 . Mirror assembly  52 ′ includes a shaft  62 ′ and a double-sided reflecting mirror  56 ′. Dial  65  is connected to one end of shaft  62 ′. Reflecting mirror  56 ′ is mounted on shaft  62 ′ so as to rotate with shaft  62 ′. Dial  65  is turned by the user&#39;s thumb to rotate the reflecting lens  56 ′ between the first and second positions. 
     FIG. 12  is a perspective view of a third embodiment of the camera phone  10 . This embodiment is similar to the previous embodiments and, therefore, similar reference numbers are used to indicate similar parts. In the embodiment of  FIG. 13 , a sliding mirror assembly  52 ″ is used in place of the rotating mirror assembly  52  and  52 ′ of the previous embodiments. Mirror assembly  52 ″ comprises a shaft  62 ″ with a thumb pad  64 ″ at each end thereof and a pair of single-sided reflecting mirrors  56 ″. The single-sided reflecting mirrors  56 ″ are mounted to the shaft  62 ″. Reflecting mirrors  56 ″ are disposed at a 90° angle with respect to one another. The mirror assembly  52 ″ slides along the axis of the shaft  62 ″ as indicated by the arrows in  FIG. 13  to selectively position the reflecting mirrors  56 ″ in the first and second optical paths, respectively. 
   The present invention may, of course, be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.