The SLM allows the researchers to control the “phase” of light reflected off of hundreds of thousands of pixels, where one pixel is one point within the liquid-crystal screen. Thus, they “controlled” the light phase by programming the SLM pixels to provide the phase relationships needed for an Airy beam.

English mathematician and astronomer Sir George Biddell Airy (1801-1892) came up with mathematical functions that predict the ability of light beams to be directed to follow what is perceived as curved paths; what are now called Airy beams. These functions were later called Airy functions in honor of George Airy’s work.

(Later, in the late-1970s, the Airy waveform was described theoretically by M.V. Berry and N.L. Balazs as a solution to the quantum equation for a free particle, what is now called the Berry-Balazs solution.)

In their optics experiment, the researchers saw the incoming light waves oscillating in synchronization to each other (“in sync”).

However, as the light went into the screen the liquid crystals caused the waves to deviate from their original path. The light waves came out of the liquid-crystal screen in an interference pattern (“out of sync”); which means that their peaks and valleys were either reinforcing each other (making for higher peaks and lower valleys) or were canceling one another totally.

One important trajectory showed a shape of a parabola; that is, a trajectory that was curved, or bended.