arXiv subjects

Muralidhar M. Balaji

Publications and source records attributed to Muralidhar M. Balaji.

2 recordsLinked to original sources

arXiv2025

Exploiting Phase Light Modulators for Low-SWaP Real-time Wavefront Correction at High-Resolution

Wavefront correction and beam tracking are critical in applications such as long-range imaging through turbulence and free-space optical communication. For instance, adaptive optics systems are employed to correct wavefront distortions caused by atmospheric turbulence and optical misalignments, while beam tracking systems maintain alignment between separate devices in free-space communication scenarios. Current state-of-the-art approaches offer several high-performance solutions, each tailored to specific correction tasks. However, integrating all these functionalities into a single device, e.g., for simultaneous adaptive wavefront correction and tracking, can significantly increase the size, weight, and power consumption (SWaP) of the final system. In this contribution, we demonstrate the use of the Texas Instruments Phase Light Modulator (PLM) as a low-SWaP, chip-scale solution for simultaneous wavefront correction and beam tracking in real-time, featuring over one million actuators. In particular, we will present and discuss multiple algorithms and optimization strategies that we have specifically developed for PLM-based wavefront correction.

physics.optics↗

arXiv2020

Synthetic Wavelength Holography: An Extension of Gabor's Holographic Principle to Imaging with Scattered Wavefronts

The presence of a scattering medium in the imaging path between an object and an observer is known to severely limit the visual acuity of the imaging system. We present an approach to circumvent the deleterious effects of scattering, by exploiting spectral correlations in scattered wavefronts. Our method draws inspiration from Gabor's attempts to improve the resolving power of electron microscopes by recording aberrated wavefronts at electron wavelengths, followed by aberration correction and playback at optical wavelengths. We extend the notion to scattered wavefronts, by interpreting the scattering of light as a source of randomized aberration. We compensate for these aberrations by mixing speckle fields recorded at two closely spaced optical wavelengths, and replaying the computationally assembled wavefront at a 'Synthetic Wavelength'. An attractive feature of our method is that it accommodates a wide variety of scattering mechanisms and operates at the physical limits of imaging in the presence of scatter. Moreover, our findings are applicable to other wave phenomena, opening up new avenues for imaging with scattered wavefronts.

physics.optics↗