Patent ID: 8797307

Claim:
A projection device for projecting useful data onto a projection surface, the projection device comprising: a drive device having a first input for coupling to a source for the useful data to be projected; at least one first output for providing a drive signal at a first wavelength; and at least one second output for providing a drive signal at a second wavelength; at least one first laser device configured to emit radiation having the first wavelength, wherein the first laser device is coupled to the first output of the drive device; at least one second laser device configured to emit radiation having the second wavelength, wherein the second laser device is coupled to the second output of the drive device; and at least one sensor device comprising at least one first photosensitive element configured to detect radiation having the first wavelength, and at least one second photosensitive element configured to detect radiation having the second wavelength, wherein the at least one sensor device comprises at least one output coupled to at least one second input of the drive device; wherein the sensor device comprises a multiplicity of first and second photosensitive elements arranged for determining at least one horizontal position of radiation having the first wavelength relative to a horizontal position of radiation having the second wavelength, wherein the drive device is configured to determine a first horizontal distance from the horizontal position of radiation having the first wavelength and the horizontal position of radiation having the second wavelength, wherein the drive device is furthermore configured to temporally shift the first and second drive signals relative to one another in a manner dependent on the first horizontal distance determined.