Removal of stratum corneum by means of light

The invention involves a method for focusing light comprising the steps of: projecting at least one pulse of light onto the surface of the skin of a patient; collecting at least a portion of the light that is reflected from the skin of the patient; projecting the collected, reflected light onto a detector; and adjusting the projection of the pulsed light onto the surface of the skin of the patient in such a manner that the signal projected onto the detector is optimized. When the light pulse is properly focused, e.g., when it is characterized by the best focus, it can be used to provide energy to form an opening in the skin of the patient. When more than one pulse of light is required to form an opening in the skin of the patient, aligning the light prior to each pulse will improve the efficiency of formation of the opening. In general, the method for aligning and focussing is the same as the method for focusing, with the difference being that aligning further includes steps for moving the spot of light formed by the light so that it strikes the surface of the skin at or near the position on the surface of the skin of the patient at which the previous spot of light struck the skin.