Controlling laser power
AssigneeSTMicroelectronics International N.V.
InventorSason Sourani
Life of this patent
Estimating the term…
Abstract
An intensity of radiation emitted from at least two laser diodes of a projecting apparatus is optimized by providing an offset distance between at least two focal points of the at least two laser diodes and providing a maximum value for radiation intensity emitted by each of the laser diodes, irrespective of simultaneous transmission by one of the laser diodes with another of the laser diodes. The intensity of the radiation emitted from each of the at least two laser diodes is adjusted such that an aggregated value of the radiation intensity emitted by all of the laser diodes within a predefined period of time may exceed a threshold value allowed for the maximum permissible exposure to radiation.
Claims19
A laser diode projecting apparatus, comprising:
- at least two laser diodes each emitting radiation towards a respective focal point at a pre-defined wavelength, and wherein the at least two respective focal points are separated from each other by at least an offset distance;
- a photodetector operative to measure light intensity near the laser diode projecting apparatus;
- a processor operative to change the offset distance between the at least two focal points based upon changes in measured light intensity occurring near the laser diode projecting apparatus;
- and
- a power controller operative to control an intensity of radiation emitted from each of the at least two laser diodes;
- wherein an aggregated value of radiation intensity emitted by all of the at least two laser diodes within a period of time exceeds a threshold value allowed for permissible exposure to radiation.
A method for optimizing the intensity of radiation emitted from at least two laser diodes of a projecting apparatus, each emitting radiation at a pre-defined wavelength, comprising:
- providing an offset distance between at least two focal points, each of which is associated with one or more of the at least two laser diodes;
- providing a maximum value for radiation intensity to be emitted by each of the at least two laser diodes, irrespective of the fact that it transmits its radiation simultaneously with at least one other laser diode;
- measuring light intensity near the projecting apparatus;
- dynamically adjusting the offset distance between the at least two focal points based upon changes in the measured light intensity occurring near the projecting apparatus;
- and
- adjusting the intensity of the radiation emitted from each of the at least two laser diodes, wherein the aggregated value of the radiation intensity emitted by all of the at least two laser diodes within a period of time exceeds a threshold value allowed for permissible exposure to radiation.
A laser diode projecting apparatus, comprising:
- at least two laser diodes each emitting radiation towards a respective focal point at a respective pre-defined wavelength, and wherein the at least two respective focal points are separated from each other by at least an offset distance;
- a photodetector operative to measure light intensity near the laser diode projecting apparatus;
- a processor operative to change the offset distance between the at least two focal points based upon changes in measured light intensity occurring at the laser diode projecting apparatus;
- and
- a power controller operative to control an intensity of radiation emitted from each of the at least two laser diodes.
Dependencies are inferred from the claim text.