Fig. 1. Simulation results of beam separation obtained with weighted GS algorithm. (a) Hologram of six-beam array; (b) focused light intensity of six-beam array; (c) variation of six-beam array’s uniformity and standard deviation with the number of iterations

Fig. 2. Multibeam parallel two-photon laser direct writing system based on polygon laser scanner. (a) Experimental setup；(b) optical path diagram

Fig. 3. Image rotator design scheme and simulation results. (a) Image rotator consists of a mirror and a prism; (b) image on detector at image rotator of 0°；(c) image on detector at image rotator of 22.5°；(d) image on detector at image rotator of 45°

Fig. 4. System parameters calibration. (a) Six-beam spacing uniformity; (b) feature size is about 150 nm and line changes to lattice when the line-width is below 150 nm; (c) rotator adjustment effect, for a rotary stage with a resolution of 0.02°，the accuracy of period spacing adjustment is up to 0.3 nm; (d) direct writing speed calibration, the speed from top to bottom is 1.494, 2.961, 5.845, 7.770 m/s, respectively

Fig. 5. Programming writing results. (a) Dot writing test, scale bar is 500 nm; (b) multichannel programming writing, scale bar is 10 μm