Fig. 3. Microscopy images of the Au–Ti surface gratings fabricated by holographic DLIP. (a) Grating with periodicities of 7.7 μm, (b) 3.28 μm, and (c) 960 nm. The effect of changing (d) tilt angle, (e) mirror-sample distance, and (f) laser beam-sample distance on grating periodicity. (g) The effect of changing energy on grating bar width. Microscopy images of 25 nm Au sample produced with (h) energy of 90 mJ and periodicity of 1.4 μm and with (i) energy of 330 mJ and periodicity of 1.3 μm. (j) The effect of altering number of pulses on grating periodicity. Optical microscopy images of grating made with 330 mJ energy at (k) 3 and (l) 4 Hz. Scale bar = 5 μm.