A method, apparatus, and article of manufacture for irradiating one or more targets within a sample with electromagnetic (EM) radiation. One or more targets within the sample are controllably defined with an acoustic field. The sample is irradiated with input EM radiation having an input wavefront. An amount of frequency shifted EM radiation is detected, wherein at least some of the input EM radiation that passes through the acoustic field at the targets is shifted in frequency to form the frequency shifted EM radiation. The input wavefront is modified, using feedback comprising the amount of the frequency shifted EM radiation that is detected, into a modified wavefront. The sample is irradiated using the input EM radiation comprising the modified wavefront, and the process is repeated as desired.