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Multiphoton microscopies (MPM), including two-photon excited fluorescence (TPEF) andsecond harmonic generation (SHG) microscopy, are robust methodologies for visualizing and assessing tissue in the context of injury and cancer. SHG, a nonlinear scattering phenomenon, offers sensitivity to structures lacking axial symmetry, with collagen—a crucial protein surrounding cells—being a prime example. Collagen plays a supporting role in wound healing and cancer progression, with alterations in its structure serving as indicative markers of both processes. This work delves into the versatility of MPM in analyzing collagen’s involvement in wound healing and disease development, while also exploring creative solutions to microscope design that enhance the viability of endoscopic implementation. Specifically, MPM with TPEF and SHG is used to visualize and quantify the steps in Achillestendon healing following mechanical and thermal injury in rats. Qualitative and quantitative MPM findings complemented traditional histology by providing additional information about collagen organization and infiltrative cell densities not readily identifiable in traditional histology. This indicates that MPM is a worthwhile way to visualize tendon wound healing from tendinopathy with and without ITU therapy. Also, the utilization of randomly sampled SHG measurements in colorectal cancer diagnosisis proposed for the first time, potentially streamlining endoscope design complexities related to the scanning mechanism. High-resolution SHG images of colorectal tumor, tumor-adjacent, and normal tissue were randomly point- and line-sampled to simulate no- and one-dimensional scanning. Results included significant differences between SHG intensity of given tissue types with only 1000 points or lines in a 1M+ pixel image. This indicates feasibility of a simpler SHG measurement system consisting of less or no scanning components. Further, the incorporation of multiple numerical aperture (NA) SHG measurem

Augmented Reality (AR) devices optically superimpose information over the real world through an optical channel, which often involves an angular bandwidth limited image guide employing Total Internal Reflection (TIR) due to material refractive index constraints. This bottlenecks to packaging size and couples it to the Field of View (FOV) and resolution. Previous architectures have focused on physically increasing the pixel count while reducing pixel size to combat this trade off, while still obeying the inverse relationship between the two. This dissertation discusses and demonstrates two multiplexing methods to address the challenge. By applying wavelength and time multiplexing similar to what is used in optical communication along with newly developed diffraction multiplexing increases the effective optical bandwidth for the AR display. Wavelength multiplexing with two wavelength sources are alternatively used in time sequential manner to in-couple the optical information through the bandwidth limited image guide, to effectively double the physically limited FOV of the image guide. At the output coupler of the image guide, a wavelength sensitive Volume Holographic Grating (VHG) angularly reflects and redistributes each part of the FOV to present a seamless full FOV image. Diffraction multiplexing in time is done by using the Digital Micromirror Device (DMD) in a diffractive manner that produces spatial modulated images at discrete angles, where each FOV per wavelength is further divided into sub-FOVs per each diffraction order. In the projection system, there is a FOV shifter then shifts the sub-FOVs side-by-side and creates a full FOV image. This multiplexing method reduces the display size while maintaining the image resolution, breaking the trade-off between package size and FOV/resolution. The added benefit of this method is that the bulky optics required for the FOV shifter can be placed closer to the image guide, reducing the overall display package size nea

The marine atmospheric boundary layer (MABL), the layer between the ocean and free troposphere, hosts a suite of important atmospheric processes such as heat and temperature flux, gas exchange of carbon dioxide and water vapor, cloud evolution, and aerosol particle transport. To measure these complex processes and provide a complete picture of the MABL, organizations such as the National Aeronautics and Space Administration (NASA), the National Oceanic and Atmospheric Administration (NOAA), and the Office of Naval Research (ONR) conduct airborne field campaigns that use a multitude of in-situ and remote sensing platforms. This dissertation introduces two studies that aim to improve airborne measurements of 1) ocean surface wind speeds and 2) atmospheric aerosol particles. Both of these studies focus on the in-situ and remote sensing instruments used in NASA’s Aerosol Cloud meTeorology Interactions oVer the western ATlantic Experiment (ACTIVATE) field campaign that took place from 2020 – 2022. The first study of this dissertation introduces a new 10 m ocean surface wind speed product from the High Spectral Resolution Lidar – generation 2 (HSRL-2) developed at the NASA Langley Research Center (LaRC) and evaluates it using coincident dropsonde surface wind speed data collected during the NASA ACTIVATE field campaign. The HSRL-2 directly retrieves vertically resolved aerosol backscatter and extinction profiles without relying on an assumed lidar ratio or other external aerosol constraints, enabling accurate estimates of the attenuation of the atmosphere and direct retrieval of surface wind speed through probing the variance of ocean wave slopes (i.e., wave-slope variance). The important findings from this study are 1) HSRL-2 surface wind speed retrieval accuracy is 0.15 m s-1 ± 1.80 m s-1, 2) dropsonde surface wind speed measurements most closely match with the Hu et al. (2008) wind speed-wave-slope variance model for surface wind speeds below 7 m s-1, showing that this

In the 20th century, rigid laparoscopes revolutionized surgery such that minimally invasive procedures are now the norm. However, these systems only provide surgeons with a two-dimensional (2D) view of the operative field and are subject to two major optical limitations: (1) the absence of binocular vision results in restricted depth perception and (2) the field of view (FOV) is restricted to the local operating region to ensure high image spatial resolution. Performing surgery through a monitor without depth perception is challenging and requires extensive training. Meanwhile, surgical accidents that occur outside of the limited FOV and have gone unnoticed may cause unnecessary trauma to the patient. In this dissertation, two novel optical designs were developed to address the two limitations and further advance this technology. The conceptualization, lens design, prototyping, calibration, and processed results are discussed for both designs. The first design is a programmable aperture light field laparoscope. It was used to investigate and explore the requirements of three-dimensional depth information extraction in a monocular form factor. Compared to state-of-the-art dual objective stereoscopic laparoscopes, this form factor preserves more design volume for transmitting more of the object scene’s light field. A programmable aperture is used to preserve the laparoscope’s conventional high resolution 2D imaging and upon demand, capture the light field. The light field information enables this system to view the object scene from different viewing angles, digitally refocus, and generate depth maps for surgical guidance in post processing. A second-generation design called a tri-aperture monocular laparoscope was then developed to address the depth perception and FOV limitations simultaneously. This system uses two displaced apertures and a custom prism to capture the stereoscopic views simultaneously, which can then be processed to generate absolute depth maps. Mea