GB2413392A

GB2413392A - Wireless communication unit with camera and flash illumination

Info

Publication number: GB2413392A
Application number: GB0409004A
Authority: GB
Inventors: Stefanos Pachnis
Original assignee: Sendo International Ltd
Current assignee: Sendo International Ltd
Priority date: 2004-04-23
Filing date: 2004-04-23
Publication date: 2005-10-26
Anticipated expiration: 2024-04-23
Also published as: GB0409004D0; WO2005104506A1; GB2413392B; WO2005104506B1

Abstract

A wireless communication unit (100) comprises a camera unit (128) operably coupled to a flash illumination arrangement (126) . The flash illumination arrangement (126) comprises one or more light sources (310) and a reflecting element (320) to, in operation, reflect generated flash light away from the wireless communication unit (100) . A housing component and set of housing components are also provided. The reflecting element (320), preferably a mirror, may also be used as a mirror by the user. The communication unit (100) may be a mobile phone, a personal digital assistant or a laptop computer.

Description

WIRELESS COMMUNICATION UNIT WITH CAMERA AND FLASH

ILLUMINATION

Field of the Invention

This invention relates to a wireless communication unit having an optical unit comprising at least a camera and an accompanying flash illumination therefor. The invention is applicable to, but not limited to, improving the flash illumination for a camera of cellular phones at a reduced power consumption level.

Background of the Invention

Next generation wireless communication units have been.. . . designed to support multimedia communication features such as digital imaging, either as video and or still :.

photographic images. This requires that the . communication units incorporate a mechanism for recording....

images such as a digital camera function. For the.

communication unit to operate in a variety of lighting .

conditions, the unit will also usually include a flash illumination arrangement, say, for recording images in low ambient light conditions.

For the few wireless communication units that currently offer a camera and a flash light feature, the flash illumination is generated using a pseudo-white light from a number of solid-state devices, such as a combination of red, green and blue light emitting diodes (LEDs). Thus, an appropriate electrical signal is applied to these t ' three diodes simultaneously to produce a pseudo-white flash light.

It is known that such flash illumination units are stand alone items, albeit that they have output characteristics that preferably should be matched to the characteristics of the digital camera system with which they are being used.

The standard mechanism to match a flash illumination arrangement to the requirements of a digital camera is to use an optical lens. The use of a lens in this manner helps to focus the limited amount of flash light to be used with the phone's internal camera. However, due to :.

the size of a mobile phone, the inventor of the present.. . invention has recognised and appreciated that it is still difficult to obtain a sufficient amount of flash light to . .e

support modern day digital camera technology. . : Furthermore, the use of an optical lens adds to the. . complexity of the wireless communication unit, reduces .

the unit's flexibility and increases the manufacturing costs. Most of these design criteria directly conflict with the key requirements of most wireless communication units, in that they must primarily meet design criteria such as minimum size and cost. This is one of the fundamental reasons why it is only a recent development

in the field of wireless communications to support

enhanced features such as multimedia functionality.

Thus, a need exists for an improved wireless communication unit having multimedia capabilities, such I ' r I as digital photography and/or video images, together with an additional artificial illumination mechanism, wherein the above-mentioned disadvantages of current wireless communication units may be alleviated.

Statement of Invention

In accordance with a first aspect of the present invention, there is provided a wireless communication unit. The wireless communication unit comprises a camera unit operably coupled to a flash illumination arrangement. The flash illumination arrangement comprises one or more light sources and a reflecting element to, in operation, reflect generated flash light :.

away from the wireless communication unit. .. . . In accordance with a second aspect of the present invention, there is provided a housing component for a . : wireless communication unit. The housing component is....

capable of supporting a camera unit and a flash. . illumination arrangement for operably coupling to one or more light sources. The housing component is adapted to support a reflecting element to reflect generated flash light away from the wireless communication unit.

In accordance with a third aspect of the present invention, there is provided a set of optical housing components for use with mobile phones, for example a set of housing components according to the aforementioned second aspect, where the housing components support a reflecting element and may have different optical properties. l - 4

Preferably, the reflecting element is of a substantially concave shape, for example a concave mirror of a mobile phone. In this manner, re-use of the mirror is achieved for flash illumination purposes. Furthermore, the flash light can be better focused by appropriate design of the curvature of the mirror. In addition, a reduced parts count of optical components is used, as there is no need for the wireless communication unit to support light guides or flash lenses.

Furthermore, by integrating the components into a housing component of the wireless communication unit the optical properties of the unit can be readily interchanged. In.... :.

this manner, multimedia functionality has been added to.. . the wireless communication unit at minimal cost and yet still provides high quality optical performance of the camera. The inventive concepts facilitate the use of a..

variety of high-resolution cameras, and in particular the ability to readily interchange/ transfer optical.

components to improve or differentiate the quality of multimedia capability in wireless communication units.

Further features of the present invention are as defined in the appended Claims.

Brief Description of the Drawing.

Exemplary embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: l l - 5 FIG. l illustrates a block diagram of a wireless communication unit adapted in accordance with the preferred embodiment of the present invention) FIG. 2 illustrates a housing part of a wireless communication unit adapted in accordance with the preferred embodiment of the present invention) FIG. 3 illustrates a schematic ray diagram of a plurality of light sources beaming light via a mirror lens, in accordance with the preferred embodiment of the present invention; and FIG. 4 illustrates a schematic ray diagram of a single.... :.

light source beaming light via a mirror lens, in.. . : accordance with an alternative embodiment of the present invention. - ::

Description of Preferred embodiments.... . :--

The preferred embodiment of the present invention will be described in terms of a mobile telephone. However, it will be appreciated that the invention may be embodied in any other type of wireless communication unit that requires or incorporates a camera and/or flash illumination unit, for example a personal digital assistant (PDA), a laptop computer, a mobile radio, etc. Referring first to FIG. l, there is shown a block diagram of part of a wireless communication unit lOO, adapted to support the inventive concepts of the preferred embodiments of the present invention. The communication J l - 6 unit 100, in the context of the preferred embodiment of the invention is a mobile phone. As such, the mobile phone 100 contains an antenna 102, preferably coupled to a duplex filter or antenna switch 104 that provides isolation between receive and transmit chains within the mobile phone 100. The receiver chain, as known in the art, includes receiver front-end circuitry 106 (effectively providing reception, filtering and intermediate or base-band frequency conversion). The front-end circuit is serially coupled to a signal processing function 108. An output from the signal processing function 108 is provided to a suitable output device 110. The functional blocks 128 and 126 represent respectively a digital camera unit and a flash Age:.

illumination unit in accordance with the preferred.. . . embodiment of the present invention, as described in greater detail with respect to FIG's 2-4. :.

As known in the art, the receiver chain also includes....

received signal strength indicator (RSSI) circuitry 112, . . which in turn is coupled to a controller 114 for maintaining overall communication unit control. The controller 114 is also coupled to the receiver front- end circuitry 106 and the signal processing function 108 (generally realised by a digital signal processor (DSP)).

The controller is also coupled to a memory device 116 that stores operating regimes, such as decoding/encoding functions and the like. A timer 118 is typically coupled to the controller 114 to control the timing of operations (transmission or reception of time-dependent signals) within the mobile phone 100. ' - 7

As regards the transmit chain, this essentially includes an input device 120, such as a microphone and keypad, coupled in series through transmitter/modulation circuitry 122 and a power amplifier 124 to the antenna 102. The transmitter/ modulation circuitry 122 and the power amplifier 124 are operationally responsive to the controller.

In order to take pictures or video images, a user accesses multimedia functions of the mobile phone by tracing through menu screens of the user interface. A user then turns on these functions by depressing appropriate keys on the keypad 120. Digital signals are then sent from the camera unit 128, to the signal... :.

processing function 108, where they are processed and.. . . Output to a local display unit 110, or stored in memory 116 for later retrieval and/or transmission. : Advantageously, the camera unit 128 and flash . illumination arrangement 126 are constructed in such a....

manner so as to co-operate and produce a high quality, optical image in poor lighting conditions, which in turn ' ' substantially reduces the requirement for post-processing in the signal processing function 108. This also reduces the load on the signal processing function 108 and improves the multimedia performance of the phone from the customer's perspective.

In accordance with the preferred embodiment of the present invention the flash illumination arrangement 126 is constructed as one or more light sources emitting light onto a reflecting unit, in contrast to the known techniques of emitting light through lens refraction l l - 8 unit. In accordance with the preferred embodiment of the present invention, the reflecting flash illumination arrangement 126 is of a substantially concave shape.

S Furthermore, the substantially concave shape of the preferred embodiment is provided by a surface of a mirror element that is provided on the exterior surface of the phone. In this manner, the mirror element in the phone performs a dual function purpose, first purely as a mirror for use by the user, and secondly as a flash light reflector. The camera unit 128 and the reflecting flash illumination arrangement 126 are preferably constructed as integral or replaceable parts of the mechanical housing of the mobile phone, where the mechanical housing.,.:' is constructed from one or more housing components. . . Thus, a mobile phone having a camera and flash illumination arrangement is provided where the mobile *a.' phone comprises a housing component with integral optical....

focusing structures, such that the aforementioned disadvantages with prior art arrangements have been substantially alleviated. Advantageously, by constructing a housing component that supports the camera unit, associated lens and a reflecting flash illumination unit that are designed and optimised for use together, the primary optical components in the mobile phone are interchangeable and can be readily replaced in either a piecemeal or a wholesale manner. This allows easy upgrading of an optical unit within the mobile phone.

Furthermore, it is envisaged that a manufacturer of such housing components will be able to market a set of l 9 - optical housing components for use with mobile phones, where the housing components may be configured to provide different optical properties. This enables a range of tiered mobile phones to be developed, with more complex high-resolution or less complex low-resolution camera units and their associated lenses and associated reflecting flash illumination units. This provides a manufacturer with an opportunity to better differentiate between their ranges of products to prospective customers.

The inventive concepts of the present invention can be better understood by reference to the following description of a preferred embodiment, as illustrated in... : FIG's 2-4. . . : Referring now to FIG. 2, a detailed view of a housing component arrangement 200 is illustrated according to the . : preferred embodiment of the present invention. The.. , housing component 200 is preferably constructed with a, , number of component parts. The preferred embodiment of the present invention comprises a radio frequency (RF) connector 202 for testing the antenna, a camera port 204 with a lens 206. The housing component is provided with the integral camera lens structure 206, which is advantageously manufactured as part of the moulding. In accordance with the preferred embodiment of the present invention, a concave mirror 208 is provided within the housing and a number of flash illumination source unit(s) 210, arranged circumferentially to the mirror 208. f

In the preferred embodiment of the present invention, the mirror 208 is configured as a concave shape. Notably, the curvature of the concave shape is dictated by the camera's flash requirements, i.e. one or more flash lights are emitted on to the concave shape and reflected away from the mobile phone into the camera viewing area, thereby increasing the light intensity of the flash illumination.

Advantageously, the concave shape used to reflect the flash light is a mirror located within the phone. As such, the mirror provides a dual function purpose, first purely as a mirror for use by the phone user, and secondly as a flash light reflector. This significantly extends the capabilities of the integrated camera 204 and flash illumination unit 210, as well as allowing a user.

to better differentiate between phone manufacturers or. . tiers of phones. '

A skilled artisan will appreciate that the inventive..

concepts of the present invention can be applied equally to a convex reflector, or indeed a substantially flat mirror or series of reflective mirror elements, dependent upon the positioning of the flash illumination source unit(s) 210.

The flash illumination source unit(s) 210, in the context of the preferred embodiment of the present invention, may be viewed as comprising, at least, any light source used to enhance a camera's ability to take a picture. The term 'illumination' encompasses any and all aspects of the light generation operation and may be used with any I. 1 - 11 - camera, for example one that is capable of working with, say, the infrared or ultraviolet range of the light spectrum. Furthermore, it is envisaged that the light source may emit any frequency of the light spectrum S including white light, infrared and/or ultraviolet waves.

In this manner, it is envisaged that one of a set of housing components for a camera unit can be designed to enable a wireless communication unit and its associated flash to work with night vision, and/or infrared heat signature features.

The camera-housing component 200 can be readily assembled onto, and removed from, the mobile phone.

Advantageously, this allows the use of a range of housing components having a variety of combinations of lenses .

206, flash illumination unit(s) 210 (or parts for the...

flash illumination unit(s)) and reflective flash.

enhancement functions such as mirror 208, to be coupled to the mobile phone. Depending upon the manufacturing ' process used in building the housing component 200, it is... ; envisaged that in most instances the flash illumination unit(s) 210 will not be included and form stand alone item(s) that are incorporated into the mobile phone rather than the optical housing per se.

In providing a mechanism to readily replace one or more of a plurality of camera features of the mobile phone, such as the camera lens 206, and/or the size of the camera port 204, and/or the curvature of the mirror 208 and/or a number of flash illumination units 210, it is thus possible to change the operation, for example the focal length and associated flash performance, of the l l - , "5 - 12 camera unit. Thus, a multi-function optical unit is interchangeable and can be replaced, removed for repair, or upgraded, whilst simultaneously ensuring the replacement or repaired or upgraded part(s) are optimised S for any new focal length. The curvature of the mirror 208 is selected to match the flash requirements of the camera in order to optimise any picture taken from the integrated camera 206.

By utilising a matched camera 206 and corresponding flash illumination unit 210, the phone may be configured to optimise the output power of the flash illumination unit 210. In particular, it is envisaged that the power output of the flash illumination unit(s) (say, flash unit 126 of FIG. 1) may be adjusted appropriately via software.. . Referring now to FIG. 3, a side view 300 and a plan view ...

350 ray diagram of a flash light arrangement, such as a ' mobile phone's flash unit, is illustrated, in accordance.. . with the preferred embodiment of the present invention.

The side view 300 illustrates a concave reflector 320, which preferably re-uses a reflective mirror contained within the optical housing component. As illustrated in the plan view 350, a number of light sources 310 are spaced around, substantially equally spaced around, the concave reflective structure 320. The light sources emit light rays 330 onto the reflective structure 320, which reflects light 340 away from the phone and into the camera's viewing angle, in accordance with the preferred embodiment of the present invention. *

/ = w Preferably, the reflective structure is configured as a concave mirror lens 320, which allows the structure to be larger and therefore reflect more light into the camera viewing area, as compared to a convex mirror lens, which would have to be relatively small. As illustrated, the preferred embodiment of the present invention utilises multiple low-power consumption light sources 310 located around the reflector 320. In this manner, the power consumption required to emit a flash light from a power constrained device, such as a battery-powered mobile phone, is reduced.

Furthermore, by using a reflective surface to reflect a.

higher proportion of light from a number of flash illumination units away from the mobile phone, heat .

dissipation within the mobile phone is improved. This A. allows the use of more temperature-tolerant (and. '.

therefore less expensive) components.

Referring now to FIG. 4, a side view 400 ray diagram of a...

flash light arrangement, such as a mobile phone's flash unit is illustrated, in accordance with an alternative embodiment of the present invention. The side view 400 again illustrates a concave reflector 320, which preferably re-uses a reflective mirror contained within the optical housing component. As illustrated in the side view 400, a single light source 310 is used to emit light 330 onto the mirror 320, which reflects light 340 away from the phone and into the camera's viewing angle.

In this configuration, a larger, single light source 310 is used. This embodiment simplifies the internal - 14 construction of the light sources, but requires a larger power-consumption light source to generate a sufficient amount of light to be reflected.

Preferably, the one or more multiple light sources use an uneven reflective surface, as described in the 3M innovations product brochure on Vikuiti_ display enhancement films, which is incorporated herein be reference. In this manner, the mirror's uneven internal structure provides a series of ridges that effectively increase the number of reflections that can be obtained from the light source(s).

..

It will be understood that the wireless communication unit, with an improved flash illumination unit, as described above, aims to provide at least one or more of A. the following advantages: , . . (i) The integrated optical design and the....' reflective arrangement result in a valuable reduction in.. . part count and assembly costs, for example no light guide or flash lens is required; (ii) An improvement in optical quality is provided by matching the light intensity from the flash illumination to the camera unit; (iii) The improved, easily replaceable nature of the optical unit allows the use of a range of cameras and flash illumination units (light source(s) and reflectors) to be used in the mobile phones; (iv) The reflective flash arrangement provides a more powerful flash to be produced, which enables improved camera operation in poor lighting conditions; 1 ' - 15 (v) The dual use of a mirror located on a phone provides re-use benefits; and/or (vi) The integrated optical design facilitates a reduction in power consumption of a multimedia wireless communication unit.

Whilst the specific and preferred implementations of the embodiments of the present invention are described above, it is clear that one skilled in the art could readily apply variations and modifications of such inventive concepts.

Thus, a wireless communication unit with optical camera and flash illumination arrangement have been described where the aforementioned disadvantages with prior art arrangements have been substantially alleviated. . , . -'' 16 Cla.

Claims

1. A wireless communication unit (100) comprises a camera unit (128)

operably coupled to a flash illumination arrangement (126) characterized in that flash illumination arrangement (126) comprises one or more light sources (310) and a reflecting element (320) to, in operation, reflect generated flash light away from the wireless communication unit (100).

2. A wireless communication unit (100) according to Claim 1 further characterized in that the reflecting element (320) is of a substantially concave shape.

3. A wireless communication unit (100) according to Claim 1 or Claim 2 further characterized in that the .

reflecting element (320) is a mirror (208) located..

substantially on an exterior surface of the wireless communication unit (100) operably coupled to one or more flash illumination light sources (310). .. .

4. A wireless communication unit (100) according to Claim 2 or Claim 3 further characterized in that a curvature of the substantially concave shape is matched to the camera unit's flash requirements.

5. A wireless communication unit (100) according to any of preceding Claims 2 to 4 further characterized in that the substantially concave shape comprises an uneven reflective surface to generate a plurality of reflective rays.

6. A wireless communication unit (100) according to any of preceding Claims 3 to 5 further characterized in that the mirror element (320) in the wireless communication unit (100) performs a dual function purpose, first as a mirror for use by a user of the wireless communication unit (100), and secondly as a flash light reflector.

7. A wireless communication unit (100) according to any of the preceding Claims further characterized in that the camera unit (128) and flash illumination arrangement (126) are housed in an optical housing component (200).

8. A wireless communication unit (100) according to Claim 7 further characterized in that the optical housing component (200) is configured as an interchangeable unit with other housing components, for example where...

alternative housing component comprise different optical

-

properties. .... ' 20; '

9. A wireless communication unit (100) according to any preceding Claim wherein the wireless communication unit (100) is a mobile phone.

10. A housing component (200) for a wireless communication unit (100) capable of supporting a camera unit (128) and a flash illumination arrangement (126) for operably coupling to one or more light sources (310) , wherein the housing component (200) is characterized by being adapted to support a reflecting element (320) to reflect generated flash light away from the wireless communication unit (100).

11. A set of optical housing components for use with one or more wireless communication units, such as mobile phones, where the optical housing components have been adapted to support a flash illumination arrangement (126) having one or more light sources (310) and a reflecting element (320) to, in operation, reflect generated flash light away from the optical housing component.

12. A wireless communication unit (100) substantially as hereinbefore described with reference to, and/or as illustrated by, FIG. 1 of the accompanying drawings.

13. A housing component (200) substantially as IS hereinbefore described with reference to, and/or as illustrated by, FIG. 2 of the accompanying drawings. ... - . .