Camera cell phone with integrated wireless mouse

1. A cellular telephone device having an integrated camera unit, comprising:

a source of illumination positioned adjacent said camera unit and configured to illuminate a portion of an underlying surface within the field of view the camera unit when said telephone is placed upon said surface;

programming effective to (a) collect a current tracking image frame, (b) compare said current tracking image frame with a prior tracking image frame, (c) compute a relative displacement between said tracking image frames, and (d) store said current tracking image frame as a prior tracking image frame;

a wireless peripheral interface, wherein said wireless peripheral interface communicates said relative displacement to a computer for use in manipulating a command element; and

an image sensor having a plurality of types of photosites, the plurality of types of photosites for collecting image data from a plurality of stored tracking image frames;

wherein said source of illumination emits monochromatic light having a peak wavelength that is approximately equal to a wavelength of peak sensitivity of one of said types of photosites.

2. The device of claim 1 , wherein the camera unit is positioned within a housing on a first side, the device further comprising:

a portion of said housing defining a recess in said first side; and

said integrated camera unit and said source of illumination being positioned within said recess.

3. The device of claim 2 , further comprising a plurality of spacing elements for suspending said first side of said housing above said underlying surface.

4. The device of claim 1 , wherein the camera unit is positioned within a housing on a first side, the device further comprising a plurality of spacing elements for suspending said first side of said housing above said underlying surface, wherein said a source of illumination and said camera unit are suspended above said underlying surface.

5. The device of claim 1 , further comprising an accessory unit engaging said cellular telephone and defining an aperture positioned over said camera unit, wherein said source of illumination is provided by said accessory unit and positioned within said aperture.

6. A device including a cellular telephone having an integrated camera unit, comprising:

a source of illumination positioned adjacent said camera unit and configured to illuminate a portion of an underlying surface within the field of view the camera unit when said telephone is placed upon said surface;

programming effective to (a) collect a current tracking image frame, (b) compare said current tracking image frame with a prior tracking image frame, (c) compute a relative displacement between said tracking image frames, and (d) store said current tracking image frame as a prior tracking image frame;

a wireless peripheral interface, wherein said wireless peripheral interface communicates said relative displacement to a computer for use in manipulating a command element; and

wherein said source of illumination emits monochromatic light having a peak wavelength that is approximately equal to a wavelength of peak sensitivity of one of a plurality of types of photosites

an accessory unit engaging said cellular telephone and defining an aperture positioned over said camera unit, wherein said source of illumination is provided by said accessory unit and positioned within said aperture, said accessory unit including a stationary lens mounted within said aperture to modify the optical power of said camera unit.

7. The device of claim 6 , the cellular telephone having a charging connector, the device further comprising an accessory unit charging connector configured to both engage said telephone charging connector and present a charging connector for engagement by said cellular telephone's charging plug.

8. The device of claim 5 , the cellular telephone having a peripheral interface, the device further comprising an accessory unit host interface for engagement with said peripheral interface, wherein said accessory unit draws power for said source of illumination through said host interface.

9. The device of claim 8 , further comprising first and second buttons provided on said accessory unit on a side opposite said aperture, wherein the state of said first and second buttons is communicated through said host and peripheral interfaces to said telephone, and by said wireless peripheral interface to a computer for use in manipulating a command element.

10. The device of claim 1 , wherein said source of illumination is a light emitting diode or laser diode.

11. The device of claim 1 , wherein the programming is effective to collect, compare, and store reduced tracking image frames, said reduced tracking image frames consisting essentially of image data collected by said one of said types of photosites.

12. The device of claim 6 , wherein the stationary lens of the accessory unit cooperates with the camera unit to capture in an unfocused manner the current tracking image of the underlying surface.