Mobile communications

A mobile videophone capable of transmitting and receiving information in mobile telecommunications systems, particularly cellular radio networks. The videophone includes a first portion and a second portion, the second portion being rotatable with respect to the first portion, the second portion including a camera for image capture, the camera including a lens, the second portion being rotatable with respect to the first portion from a first position, in which the camera lens is protected by said first portion, to a second position in which the first portion does not protect the camera lens.

FIELD OF THE INVENTION

The invention relates to a portable image capture device including a first portion and a second portion, the second portion being rotatable with respect to the first portion, the second portion including a camera for image capture. More specifically but not exclusively, the invention relates to portable videophones capable of receiving and transmitting information in mobile telecommunications systems, such as cellular radio networks. Such devices may be referred to as mobile videophones.

The inclusion of a video camera and display in a mobile telephone handset so as to allow mobile video-conferencing has been proposed in various documents.

U.S. Pat. No. 5,414,444 (AT&T) describes a communicator having an openable cover which contains an LCD-type display and a video camera. In this document, the video camera is reorientable when the cover is open, and the communicator includes mechanical apparatus interactive with the closing of the cover to reset the camera to a standard position after use.

A further form of mobile videophone is proposed in PCT publication number WO97/26744. This documents describes a portable telephone having a display and a camera mounted in the main body of the phone. The camera is mounted on a rotational pivot to enable it to receive images from various directions.

SUMMARY OF CERTAIN INVENTIVE ASPECTS

According to one aspect of the invention there is provided a portable image capture device including a first portion and a second portion, the second portion being rotatable with respect to the first portion, the second portion including a camera for image capture, the camera including a lens, the first portion including a display for viewing images captured by the camera, the second portion being rotatable with respect to the first portion from a first position, in which the camera lens is protected by said first portion, to a second position in which the first portion does not protect the camera lens, the device including means responsive to rotation of said first portion with respect to said second portion, the means being responsive to rotation of said second portion beyond a predetermined position to invert an image produced by said camera.

According to a further aspect of the invention there is provided a portable image capture device including a first portion and a second portion, the second portion being rotatable with respect to the first portion, the second portion including a camera for image capture, the second portion being rotatable with respect to the first portion from a first position to a second position, wherein said device includes means responsive to rotation of said first portion with respect to said second portion from said first position to switch on said camera, said responsive means being responsive to rotation of said second portion beyond a predetermined position to invert an image produced by said camera.

According to a further aspect of the invention there is provided a mobile videophone including a main body portion and a camera housing which is rotatably mounted on the main body portion, the main body portion being generally elongate and having a top, a lower end, two sides and a front surface on which a display is mounted, said housing being mounted on one of said sides, the videophone including means responsive to rotation of the camera housing with respect to the main body portion beyond a predetermined position to invert an image produced by the videophone.

DETAILED DESCRIPTION OF CERTAIN INVENTIVE EMBODIMENTS

FIG. 1shows a schematic block diagram of the main functional elements which may be included commonly to the different embodiments of the invention, which elements are each individually known and will not be described in detail herein. A main processor36may be a conventional programmable microprocessor, or a special purpose or specially configured unit (e.g. a digital signal processor) could alternatively be used. A read-only memory (ROM)38is connected to the processor36for the storage of control programs, data and images. The ROM38can be implemented by any appropriate technology, for example, by a flash PROM. A random-access memory (RAM)40is connected to the processor36via a bus42, is used as a working storage and for the storage of data and images captured using a CCD video camera24.

Signals relating to the data captured by the camera are passed via a camera interface44to the processor36to be processed. The camera interface44also provides the video codec46with a digital representation of the captured data from the camera24, where it can be suitably processed for display and/or transmission to the mobile communications system. An indicator light may be connected to the processor to report successful capture of data and/or images from the camera24and may also be used during video conferencing to indicate the correct usage of the device.

The camera interface44carries out all the necessary signal conditioning as required on receiving images from the camera24. Signal conditioning will depend on the exact configuration of the camera but preferably comprises signal conditioning to enable accurate analogue to digital conversion with sufficient buffering of the captured data. The camera24will include all the necessary support circuitry to produce a fully functional camera delivering a fully formatted video signal. The camera24may also include circuitry to regulate the voltage for power supply control and a suitable output buffer to directly drive a standard VDU should the videophone be connected to an external device.

The camera24is rotatably mounted on the videophone to allow adjustment of the orientation of the camera to enable the user to point the camera in alternative directions. The positioning of the camera24can be adjusted manually. The rotational position of the camera is detected by a rotation sensor, which feeds an output to the processor36whereby operation of the camera may be controlled in dependence on the rotational position of the camera. The processor36may switch the camera on in response to rotational movement of the camera. The processor may also control an image manipulation to flip an image produced by the camera in response to detection of the camera in a certain rotational position or range of positions. Such an image inversion is preferably performed by means of software-based data processing in the videophone before the image data is transmitted to the other party.

The on/off button29is connected via a suitable interface to a power control module50. The power control module50responds to the operation of this button in a powered down state to connect the battery32to the processor36. The power control module50may also control the charging of the battery32. The power control module50will also control the power requirements when a standard AC/DC power supply is connected to the videophone.

A display interface52connects a graphics display26via the bus42to the processor36. The display interface52responds to instructions from the processor136to drive the built-in display26in a conventional manner. The display interface52may also incorporate the necessary circuitry to drive a standard external video display unit via a suitable connector54. The display is capable of displaying still and/or video images captured by the camera24.

The display26is provided with a touch-screen. A touch-screen interface55couples the touch-sensitive display26to the processor36via the bus42. The touch-screen is a device independent of the video display26, for example, a transparent touch-screen membrane is placed over the display26and connected appropriately.

The processor36can be arranged to transmit to the display26a menu of user selectable items, and to be responsive to a location at which the screen is touched for input of the user selection of an item. The touch-sensitive screen can then thus be used as a dynamic and reconfigurable user interface. Touch-screen entry can be used in place of or in addition to the entry's commands from an external keyboard or voice command if appropriate. Additionally, the touch-screen area can be configured as a general purpose scribing area to allow entry of data and written commands.

An audio interface56connects the audio receiver means, consisting of one or more microphones18and audio transmitter means such as one or more ear-pieces and/or speakers16to the processor36and carries out all the necessary signal conditioning as required to output audio signals and to receive audio signals.

The videophone includes infra-red data reception and transmission capabilities and a suitable infra-red interface60is provided. The infra-red interface connects an infra-red port to the processor36via the bus42.

A radio-frequency (RF) interface62is also connected via the bus42to convert any data to be transmitted into signals for driving an RF transmitter64, and converts signals from an RF receiver66into data to be passed via the bus to the relevant interfaces. The RF transmitter64and the RF receiver66are connected to a radio antenna28. This RF interface62consequently enables wireless communications between the videophone and the mobile communications system, to allow the transmission and reception of still and/or video images to and from other similar videophones via the mobile communications system.

The processor36is programmed by means of control programs and data stored in the ROM38and in use, the RAM40, to receive signals from the camera24via camera interface44, to interpret those signals and to derive data therefrom which are displayed on display26and which can be stored in the RAM40or any other suitable memory device.

Other interfaces may be included to increase the flexibility of the unit, for example, RS232 interface58may be included, for transmitting and receiving data in RS232 format. The RS232 interface enables the processor36to be connected via the bus42to allow the connection of other compatible devices to the videophone through a standard RS232 cable.

Depending on the refresh rate used and the number of pixels used in the images, video image data transmitted and received by the videophone may require compression for transfer via a low data rate radio channel, such as those currently available in known cellular radio networks. The video data may be compressed using the MPEG-4 standard. Alternatively, the video images captured may be compressed into a different format suitable for transmitting the data derived across the mobile communications system, such as that disclosed in International Patent Publication WO95/20296.

FIG. 2is a plan view from above of an embodiment of a portable videophone100in accordance with the invention. The videophone includes a main body portion102housing the display26on its front surface. A generally cylindrical camera housing104is rotatably mounted to the body portion102. The camera is housed behind a lens106which is built in to the housing104. The body portion102is generally elongate and has an upper end108, in the area of which the housing104projects from the left side of the body102. A protective shoulder110located at the upper end108projects from the same side of the body102above the housing104, and is arranged to fit flush with the upper surface of the projecting part of the housing104. An earpiece housing a loudspeaker16is located on the front surface of the body102in the area of the upper end108. The body102has a lower end112in the area of which a mouthpiece housing a microphone18and control buttons114are located.

The housing104is rotatable about an axis generally perpendicular to the upper end108of the body102, from a protected position in which the camera is directed towards the upper end108and the lens is hidden behind the shoulder110, clockwise (when viewed from the left side of the body102) through a position in which the camera is directed towards the front of the body102, a position in which the camera is directed towards the lower end112, and a position in which the camera is directed towards the rear of the body102. The housing is thus rotatable through at least 270 degrees.

The shoulder110generally protects the housing104, and in particular acts as a rigidly mounted lens cap to protect the camera lens104when the housing is rotated to the protected position, which is shown in greater detail in FIG.3. As further shown inFIG. 3, the housing104also includes a frictional contact means116, producing greater frictional force on manual manipulation than the remainder of the housing104, at the outer periphery of the housing104. The frictional contact means may for example be in the form of a rubber o-ring securely held on the housing104.

The rotation sensor48is capable of sensing when the housing104is located in the protected position, in response to which the processor36may automatically switch off the camera24. Similarly, when the housing104is rotated from the protected position, the processor may automatically switch on the camera24. Furthermore, the rotation sensor48is capable of sensing when the camera is directed towards the rear of the body portion, in response to which the processor may initiate an image inversion, or flip, to be carried out at the camera interface44or the video codec46before the image is coded by the codec46.

The invention is not limited in application to videophones. Aspects of the invention may be implemented in other types of portable devices, such as still and video cameras.

It is to be understood that the embodiments described above are preferred embodiments only. Namely, various features may be omitted, modified or substituted by equivalents without departing from the scope of the present invention, which is defined in the accompanying claims.