Extended Data Fig. 3: Phase voxel writing.
From: Laser writing in glass for dense, fast and efficient archival data storage
(a) Schematics of (i) a laser pulse focused inside the glass medium, and (ii) the laser-induced RIchange in the excitation region. (b) Schematics of the amplitude multiplexed data writing: different symbols are represented/written by different amplitudes of the laser pulses. (c) Example of phase-contrast microscopy images of 2-bit data (4 modification levels) written in borosilicate glass taken at two different depths of a single voxel. (i) Image of the positive contrast of a laser induced RImodification. (ii) Negative contrast image of the voxel obtained at a slightly different depth. (iii) Difference of positive and negative contrast images of the voxel with increased signal to noise ratio. (d) Example histogram of the normalized voxel intensity distribution showing the separation of four brightness levels. (e) Write (left) and read (right) research instruments.
