Simultaneously, a SIM system consisting of a 488-nm continuous-wave laser and a spatial light modulator (SLM) generates ...

In the pulsed beam case, the laser actually sweeps across your ear at the desired audio frequency. Each method has advantages and disadvantages. Modulated light creates a higher fidelity sound.

The new modulator can be used with any frequency from 10 megahertz to 1.14 ... and makes use of the interaction between light ...