5 research outputs found

    Field of View Based Optimization of Aspheric Designed Geometric-Phase Doublet Lenses

    Full text link
    Here we study aspheric phase pattern geometric-phase lenses through the design of doublet lenses in Zemax Optic Studio and in MATLAB using a simple ray tracing code. The solutions developed use variable spacer distances and are solved monochromatically (at 633 nm) and polychromatically (at 450, 532, and 633 nm). After selecting a Zemax generated polychromatically optimized doublet solution, we fabricated the lens utilizing liquid crystal films and direct writing. We characterized the liquid crystal alignment quality, efficiencies, and spot performance of this lens in comparison to a standard spherical singlet of the same back focal length and diameter (24.5 mm diameter and 40 mm back focal length at 633 nm). With this aspheric lens profile, we realize the development of novel focusing phase surfaces

    Volumetric analysis of the aging auditory pathway using high resolution magnetic resonance histology

    No full text
    Numerous shown consequences of age-related hearing loss have been unveiled; however, the relationship of the cortical and subcortical structures of the auditory pathway with aging is not well known. Investigations into neural structure analysis remain sparse due to difficulties of doing so in animal models; however, recent technological advances have been able to achieve a resolution adequate to perform such studies even in the small mouse. We utilize 12 members of the BXD family of recombinant inbred mice and aged separate cohorts. Utilizing novel magnetic resonance histology imaging techniques, we imaged these mice and generated high spatial resolution three dimensional images which were then comprehensively labeled. We completed volumetric analysis of 12 separate regions of interest specific to the auditory pathway brainstem nuclei and cortical areas with focus on the effect of aging upon said structures. Our results showed significant interstrain variation in the age-related effect on structure volume supporting a genetic influence in this interaction. Through multivariable modeling, we observed heterogenous effects of aging between different structures. Six of the 12 regions of interests demonstrated a significant age-related effect. The auditory cortex and ventral cochlear nucleus were found to decrease in volume with age, while the medial division of the medial geniculate nucleus, lateral lemniscus and its nucleus, and the inferior colliculus increased in size with age. Additionally, no sex-based differences were noted, and we observed a negative relationship between auditory cortex volume and mouse weight. This study is one of the first to perform comprehensive magnetic resonance imaging and quantitative analysis in the mouse brain auditory pathway cytoarchitecture, offering both novel insights into the neuroanatomical basis of age-related changes in hearing as well as evidence toward a genetic influence in this interaction. High resonance magnetic resonance imaging provides a promising efficacious avenue in future mouse model hearing loss investigations

    ON-SKY PERFORMANCE ANALYSIS OF THE VECTOR APODIZING PHASE PLATE CORONAGRAPH ON MagAO/Clio2

    No full text
    We report on the performance of a vector apodizing phase plate coronagraph that operates over a wavelength range of 2-5 mu m. and is installed in MagAO/Clio2 at the 6.5 m Magellan Clay telescope at Las Campanas Observatory, Chile. The coronagraph manipulates the phase in the pupil to produce three beams yielding two coronagraphic point-spread functions (PSFs) and one faint leakage PSF. The phase pattern is imposed through the inherently achromatic geometric phase, enabled by liquid crystal technology and polarization techniques. The coronagraphic optic is manufactured using a direct-write technique for precise control of the liquid crystal pattern. and multitwist retarders for achromatization. By integrating a linear phase ramp to the coronagraphic phase pattern, two separated coronagraphic PSFs are created with a single pupil-plane optic, which makes it robust and easy to install in existing telescopes. The two coronagraphic PSFs contain a 180 degrees dark hole on each side of a star, and these complementary copies of the star are used to correct the seeing halo close to the star. To characterize the coronagraph, we collected a data set of a bright (m(L) = 0-1) nearby star with similar to 1.5 hr of observing time. By rotating and optimally scaling one PSF. and subtracting it from the other PSF, we see a contrast improvement by 1.46 magnitudes at 3.5 lambda/D. With regular angular differential imaging at 3.9 mu m, the MagAO vector apodizing phase plate coronagraph delivers a 5 sigma Delta mag contrast of 8.3 (= 10(-3.3)) at 2 lambda/D and 12.2 (= 10(-4.8)) at 3.5 lambda/D.Netherlands Organization for Scientific Research (NWO); European Research Council [678194]; NASA Exoplanets Research Program (XRP) [NNX16AD44G]This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

    ON-SKY PERFORMANCE ANALYSIS OF THE VECTOR APODIZING PHASE PLATE CORONAGRAPH ON MagAO/Clio2

    No full text
    We report on the performance of a vector apodizing phase plate coronagraph that operates over a wavelength range of 2−5μ2-5 \mum and is installed in MagAO/Clio2 at the 6.5 m Magellan Clay telescope at Las Campanas Observatory, Chile. The coronagraph manipulates the phase in the pupil to produce three beams yielding two coronagraphic point-spread functions (PSFs) and one faint leakage PSF. The phase pattern is imposed through the inherently achromatic geometric phase, enabled by liquid crystal technology and polarization techniques. The coronagraphic optic is manufactured using a direct-write technique for precise control of the liquid crystal pattern, and multitwist retarders for achromatization. By integrating a linear phase ramp to the coronagraphic phase pattern, two separated coronagraphic PSFs are created with a single pupil-plane optic, which makes it robust and easy to install in existing telescopes. The two coronagraphic PSFs contain a 180∘^\circ dark hole on each side of a star, and these complementary copies of the star are used to correct the seeing halo close to the star. To characterize the coronagraph, we collected a dataset of a bright (mL=0−1m_L=0-1) nearby star with ∼\sim1.5 hr of observing time. By rotating and optimally scaling one PSF and subtracting it from the other PSF, we see a contrast improvement by 1.46 magnitudes at 3.5λ/D3.5 \lambda/D. With regular angular differential imaging at 3.9 μ\mum, the MagAO vector apodizing phase plate coronagraph delivers a 5σ Δ5\sigma\ \Delta mag contrast of 8.3 (=10−3.3=10^{-3.3}) at 2 λ/D\lambda/D and 12.2 (=10−4.8=10^{-4.8}) at 3.5λ/D3.5 \lambda/D.Comment: Published in ApJ. 8 figures, 1 table. Received 2016 June 17; revised 2016 November 3; accepted 2016 November 28; published 2017 January 1
    corecore