Using an acousto-optic modulator as a fast spatial light modulator

High-speed spatial light modulators (SLM) are crucial components for free-space communication and structured illumination imaging. Current approaches for dynamical spatial mode generation, such as liquid crystal SLMs or digital micromirror devices, are limited to a maximum pattern refresh rate of 10 kHz and have a low damage threshold. We demonstrate that arbitrary spatial profiles in a laser pulse can be generated by mapping the temporal radio-frequency (RF) waveform sent to an acousto-optic modulator (AOM) onto the optical field. We find that the fidelity of the SLM performance can be improved through numerical optimization of the RF waveform to overcome the nonlinear effect of AOM. An AOM can thus be used as a 1-dimensional SLM, a technique we call acousto-optic spatial light modulator (AO-SLM), which has 50 mu m pixel pitch, over 1 MHz update rate, and high damage threshold. We simulate the application of AO-SLM to single-pixel imaging, which can reconstruct a 32x32 pixel complex object at a rate of 11.6 kHz with 98% fidelity. (c) 2023 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

We demonstrate a high-speed spatial light modulator (SLM) that can generate arbitrary spatial profiles in a laser pulse by mapping the temporal radio-frequency (RF) waveform to the optical field using an acousto-optic modulator (AOM). The fidelity of the SLM performance can be improved through numerical optimization of the RF waveform to overcome the nonlinearity of the AOM. The resulting acousto-optic SLM has a 50 μm pixel pitch, over 1 MHz update rate, and high damage threshold.