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Phase light modulator (PLM) by MEMS mirror array operating in a piston-mode motion enables a high-speed diffractive beam steering in a random-access and flexible manner that makes a lidar system more intelligent and adaptive. Diffraction efficiency is determined by the range of the piston motion of the MEMS array; consequently, a larger range of the piston motion is required for beam steering in infrared, such as for lidar. We demonstrated how the range of the piston motion is optically enhanced by a factor of two with a light-recycling optics based on Talbot self-imaging. The proposed optical architecture extends the usable range of the wavelength so that a MEMS-PLM designed for visible wavelength is applicable for a high-efficiency beam steering at an infrared wavelength of 1550 nm with an improved diffraction efficiency of 30%.

The recent development of the Micro Electromechanical System (MEMS) Phase Light Modulator (PLM) enables fast laser beam steering for lidar applications by displaying a Computer-Generated Hologram (CGH) without employing an iterative CGH calculation algorithm. We discuss the application of MEMS PLM (Texas Instruments PLM) for quasi-continuous laser beam steering by deterministically calculated CGHs. The effect on the diffraction efficiency of PLM non-equally spaced phase levels was quantified. We also address the CGH calculation algorithm and an experimental demonstration that steered and scanned the beam into multiple regions of interest points, enabling beam steering for lidar without sequential raster scanning.

Real-time, simultaneous, and adaptive beam steering into multiple regions of interest replaces conventional raster scanning with a less time-consuming and flexible beam steering framework, where only regions of interest are scanned by a laser beam. CUDA-OpenGL interoperability with a computationally time-efficient computer-generated hologram (CGH) calculation algorithm enables such beam steering by employing a MEMS-based phase light modulator (PLM) and a Texas Instruments Phase Light Modulator (TI-PLM). The real-time CGH generation and display algorithm is incorporated into the beam steering system with variable power and scan resolution, which are adaptively controlled by camera-based object recognition. With a mid-range laptop GPU and the current version of the MEMS-PLM, the demonstrated scanning speed can exceed 1000 points/s (number of beams > 5) and potentially exceeds 4000 points/s with state-of-the-art GPUs.

In the realm of astronomical scientific exploration, deployable and scalable approaches in space telescope systems are reshaping our understanding of the universe. Two revolutionary membrane-based space telescope designs, on-axis OASIS (Orbiting Astronomical Satellite for Investigating Stellar Systems) and off-axis SALTUS (Single Aperture Large Telescope for Universe Studies), have been developed as mid/far-infrared telescope concepts featuring an inflatable primary mirror. Through the scalable primary aperture design, these deployable space telescopes leverage an all-encompassing optical architecture that taps into the uncharted potential of extremely large telescope apertures. These visionary mission and optical designs pave the way for the next generation scalable telescopes of unprecedented dimensions and diffraction-limited imaging resolutions.

In a lidar system, replacing moving components with solid-state devices is highly anticipated to make a reliable and compact lidar system, provided that a substantially large beam area with a large angular extent as well as high angular resolution is assured for the lidar transmitter and receiver. A new quasi-solid-state lidar optical architecture employs a transmitter with a two-dimensional MEMS mirror for fine beam steering at a fraction of the degree of the angular resolution and is combined with a digital micromirror device for wide FOV scanning over 37 degree while sustaining a large aperture area of 140 mm squared. In the receiver, a second digital micromirror device is synchronized to the transmitter DMD, which enables a large FOV receiver. An angular resolution of 0.57°(H) by 0.23° (V) was achieved with 0.588 fps for scanning 1344 points within the field of view.

The metrology of membrane structures, especially inflatable, curved, optical surfaces, remains challenging. Internal pressure, mechanical membrane properties, and circumferential boundary conditions imbue highly dynamic slopes to the final optic surface. Here, we present our method and experimental results for measuring a 1 m inflatable reflector’s shape response to dynamic perturbations in a thermal vacuum chamber. Our method uses phase-measuring deflectometry to track shape change in response to pressure change, thermal gradient, and controlled puncture. We use an initial measurement as a virtual null reference, allowing us to compare 500 mm of measurable aperture of the concave f/2, 1-meter diameter inflatable optic. We built a custom deflectometer that attaches to the TVAC window to make full use of its clear aperture, with kinematic references behind the test article for calibration. Our method produces 500 × 500 pixel resolution 3D surface maps with a repeatability of 150 nm RMS within a cryogenic vacuum environment (T = 140 K, P = 0.11 Pa).

Two disruptive space telescope concepts are being designed and developed at the University of Arizona; these are the 20-meter OASIS (Orbiting Astronomical Satellite for Investigating Stellar Systems) and 8.5-meter Nautilus. OASIS combines break-through inflatable aperture and adaptive optics techniques to realize the dream of a 20 + meter class spaceborne terahertz/far-infrared telescope. In the Nautilus visible/near-infrared telescope concept, conventional primary mirrors are replaced by an ~8.5-meter MODE (Multi-order diffractive engineered) lens with 10 times lower areal density and up to 100 times lower mis-alignment sensitivity over traditional systems, enabling large-diameter optical space telescopes. The OASIS and Nautilus concepts have the potential to greatly reduce mission costs and risks compared to the current state of the art.

We use convolutional neural networks to recover images optically down-sampled by \\(6.7\\times\\) using coherent aperture synthesis over a 16 camera array. Where conventional ptychography relies on scanning and oversampling, here we apply decompressive neural estimation to recover full resolution image from a single snapshot, although as shown in simulation multiple snapshots can be used to improve SNR. In place training on experimental measurements eliminates the need to directly calibrate the measurement system. We also present simulations of diverse array camera sampling strategies to explore how snapshot compressive systems might be optimized.

In this dissertation, we investigate practical performances and limitations of page-based and bit-based holographic volume recording approaches by comparing the two schemes while taking into account optical aberrations in conjunction with lens designs. We have shown that the Strehl intensity ratio of the reconstruction reference beam approximates the diffraction efficiency for the bit-based recording. By the Strehl intensity ratio representation, we have compared the media tilt tolerance and shown that an optimum value of the focusing NA (∼0.7) exists to maximize the tilt tolerance for the bit-based approach. Most importantly, the tilt tolerance for the bit-based system is about magnitude larger compared to that of the page-based system. Lens designs for page-based system involve series steps including first-order power arrangements, third-order designs, fifth-order aberration balancing and ray-trace optimizations. So far, no systematic lens design approach aiming to maximize imaging NA while using less lens elements has been employed. By focusing on chief-ray deflection angles, the optimum first-order power arrangement, such that a negative element is placed on the Fourier plane, has been identified. Following the first-order design, we have identified that a bi-aspherical meniscus lens or air-spaced spherical lenses are minimum configurations to compensate for all the third-order aberrations. Balancing of aberrations is essential to increase the imaging NA, but has not been theoretically investigated. By numerically solving expression of variance of wave aberrations, we have shown that four realizable balancing exist and two of them are practically usable and identical. Finally, we have presented high imaging NA designs having single-element (NA ∼ 0.5), double-element (NA ∼ 0.7) and triple-element (NA ∼ 0.8). Also, the imaging and focusing NA of 0.45 system is designed which are usable both for the page- and bit-based holographic recordings. In conclusion, we have confirmed a high potential of the bit-based holographic storage systems especially in terms of the robustness of the system. We have conducted systematic lens designs of high imaging NA systems having small number of lens elements, which can be a general design guideline for designing lenses in page-based holographic storage systems.

Coherent illumination reflected by a remote target may be secondarily scattered by intermediate objects or materials. Here we show that phase retrieval on remotely observed images of such scattered fields enables imaging of the illuminated object at resolution proportional to \\(\\lambda R_s/A_s\\), where \\(R_s\\) is the range between the scatterer and the target and \\(A_s\\) is the diameter of the observed scatter. This resolution may exceed the resolution of directly viewing the target by the factor \\(R_cA_s/R_sA_c\\), where \\(R_c\\) is the range between the observer and the target and \\(A_c\\) is the observing aperture. Here we use this technique to demonstrate \\(\\approx 32\\times\\) resolution improvement relative to direct imaging.