Quasi-static microscanner with linearized scanning for an adaptive 3D laser camera

Abstract

This paper presents a gimbaled MEMS scanning mirror (MSM) especially developed for adaptive raster scanning in a novel 3D ToF laser camera. Large quasi-static deflections of ±10° are provided by vertical comb drives in vertical direction in contrast to resonant horizontal scanning of the 2.6x3.6mm elliptical mirror at 1600 Hz and 80° optical scan range. For position feedback piezo-resistive position sensors are integrated on chip for both axes. To guarantee the full reception aperture of effective 5 mm a synchronized driven MEMS scanner array-consisting of five hybrid assembled MEMS devices-are used in a novel 3D ToF laser scanner enabling a distance measuring rate of 1MVoxel/s and an uncertainty of ToF distance measurement of 3...5 mm at 7.5 m measuring range for a gray target

MEMS Mirrors for LiDAR: A Review

“…Electrothermal MEMS mirrors (one example is shown in Figure 15(b)) have the advantages of large non-resonant scan angle and high fill factor [109]; their resonant frequencies are mostly are in the range of 0.4-3 kHz [104][105][106][107]109]. Both electrostatic mirrors [112] and piezoelectric mirrors [87] can achieve high resonant frequencies, but their quasi-static scanning angles are relatively small (Figures 15(c As can be seen in Table 6, the MEMS mirrors with high FoM are mainly electromagnetic MEMS mirrors [80,111] and one electrothermal mirror [109]. Electromagnetic MEMS mirrors (one example is shown in Figure 15a) have the advantage of achieving large apertures and wide angles at the same time [80,111].…”

“…Electrothermal MEMS mirrors (one example is shown in Figure 15b) have the advantages of large non-resonant scan angle and high fill factor [109]; their resonant frequencies are mostly are in the range of 0.4-3 kHz [104][105][106][107]109]. Both electrostatic mirrors [112] and piezoelectric mirrors [87] can achieve high resonant frequencies, but their quasi-static scanning angles are relatively small (Figure 15c,d).…”