Retinal imaging spectroscopy can provide functional maps using chromophore spectra. For example, oxygen saturation maps show ischemic areas from diabetes and venous occlusions. Obtaining retinal spatial-spectral data has been difficult due to saccades and long data acquisition times (>5 s). We present a snapshot imaging spectrometer with far-reaching applicability that acquires a complete spatial-spectral image cube in approximately 3 ms from 450 to 700 nm with 50 bands, eliminating motion artifacts and pixel misregistration. Current retinal spectral imaging approaches are incapable of true snapshot operation over a wide spectral range with a large number of spectral bands. Coupled to a fundus camera, the instrument returns true color retinal images for comparison to standard fundus images and for image validation while the patient is still dilated. Oxygen saturation maps were obtained with a three-wavelength algorithm: for healthy subjects arteries were approximately 95% and veins 30 to 35% less. The instrument is now undergoing clinical trials.

[1] The NASA Discovery Moon Mineralogy Mapper imaging spectrometer was selected to pursue a wide range of science objectives requiring measurement of composition at fine spatial scales over the full lunar surface. To pursue these objectives, a broad spectral range imaging spectrometer with high uniformity and high signal-to-noise ratio capable of measuring compositionally diagnostic spectral absorption features from a wide variety of known and possible lunar materials was required. For this purpose the Moon Mineralogy Mapper imaging spectrometer was designed and developed that measures the spectral range from 430 to 3000 nm with 10 nm spectral sampling through a 24 degree field of view with 0.7 milliradian spatial sampling. The instrument has a signal-to-noise ratio of greater than 400 for the specified equatorial reference radiance and greater than 100 for the polar reference radiance. The spectral cross-track uniformity is >90% and spectral instantaneous field-of-view uniformity is >90%. The Moon Mineralogy Mapper was launched on Chandrayaan-1 on the 22nd of October. On the 18th of November 2008 the Moon Mineralogy Mapper was turned on and collected a first light data set within 24 h. During this early checkout period and throughout the mission the spacecraft thermal environment and orbital parameters varied more than expected and placed operational and data quality constraints on the measurements. On the 29th of August 2009, spacecraft communication was lost. Over the course of the flight mission 1542 downlinked data sets were acquired that provide coverage of more than 95% of the lunar surface. An end-to-end science data calibration system was developed and all measurements have been passed through this system and delivered to the Planetary Data System (PDS.NASA.GOV). An extensive effort has been undertaken by the science team to validate the Moon Mineralogy Mapper science measurements in the context of the mission objectives. A focused spectral, radiometric, spatial, and uniformity validation effort has been pursued

Using an optical vortex coronagraph and simple adaptive optics techniques, we have made the first convincing demonstration of an optical vortex coronagraph that is coupled to a star gazing telescope. We suppressed by 97% the primary star of a resolvable binary system, Cor Caroli. The stars had an angular separation of 1.9lambda/D at our imaging camera. The secondary star suffered no suppression from the vortex lens.

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A transmission-type nonmechanical multiple-angle beam-steering device that uses liquid-crystal blazed grating has been developed. Sixteen steering angles with a contrast ratio of 18 has been demonstrated. A detailed analysis of the liquid-crystal and poly͑methyl methacrylate͒ blazed-grating deflector was carried out to provide guidance during the deflector's development. A manufacturing offset compensation technique is proposed to improve the device's performance greatly. A hybrid approach utilizing electrically generated blazed grating combined with the cascading approach described here yields in excess of 500 deflecting angles.

Novel optical components based on metasurfaces (metalenses) offer a new methodology for microlens arrays. In particular, metalens arrays have the potential of being monolithically integrated with infrared focal plane arrays (IR FPAs) to increase the operating temperature and sensitivity of the latter. In this work, we demonstrate a new type of transmissive metalens that focuses the incident light (λ = 3 -5 μm) on the detector plane after propagating through the substrate, i.e. solid-immersion type of focusing. The metalens is fabricated by etching the backside of the detector substrate material (GaSb here) making this approach compatible with the architecture of back-illuminated FPAs. In addition, our designs work for all incident polarizations. We fabricate a 10x10 metalens array that proves the scalability of this approach for FPAs. In the future, these solid-immersion metalenses arrays will be monolithically integrated with IR FPAs.Infrared focal plane arrays (IR FPAs) are commonly used in thermal cameras, medical imaging devices and for sensing applications such as wavefront sensing 1 . Microlenses and microspheres have been previously used as optical concentrators 2-9 to increase the operating temperature of IR FPAs, but they are typically made of materials different from the detector materials and therefore these approaches require additional deposition and alignments steps. Recently, mid-wavelength IR (MWIR) nBn detectors monolithically integrated with spherical concentrators fabricated on the detector backside were demonstrated 10 . This provides an alternative approach for realization of microlens-integrated detectors in which microlenses are made from the detector substrate material. The newly developed metasurfaces are a promising candidate for the next generation optical concentrators that can also be monolithically integrated with IR FPAs with small pixels. They can be fabricated from the same material as the substrate and are flat, ultrathin, and lightweight. Metasurfaces consist of optical components based on arrays of optical resonators with subwavelength separation. By accurately designing the optical properties of each element of the array, the wavefront of the incident light can be reshaped and redirected at will 11 . Numerous devices based on metasurfaces have been developed, including metasurface lenses (metalenses), waveplates, polarimeters, and holograms [12][13][14][15][16][17][18][19] .To be compatible with current IR FPAs, these metalenses have to feature several unique characteristics which differentiate them from the metalenses demonstrated so far. The majority of IR FPAs are back-illuminated (through the substrate), so the lens needs to be transmissive and of the immersion type to focus light in the detector materials. The lens also needs to be fabricated on

The design, characteristics, and first test flight results are described of the Portable Remote Imaging Spectrometer, an airborne sensor specifically designed to address the challenges of coastal ocean remote sensing. The sensor incorporates several technologies that are demonstrated for the first time, to the best of our knowledge, in a working system in order to achieve a high performance level in terms of uniformity, signal-to-noise ratio, low polarization sensitivity, low stray light, and high spatial resolution. The instrument covers the 350-1050 nm spectral range with a 2.83 nm sampling per pixel, and a 0.88 mrad instantaneous field of view, with 608 cross-track pixels in a pushbroom configuration. Two additional infrared channels (1240 and 1610 nm) are measured by a spot radiometer housed in the same head. The spectrometer design is based on an optically fast (F/1.8) Dyson design form coupled to a wide angle two-mirror telescope in a configuration that minimizes polarization sensitivity without the use of a depolarizer. A grating with minimum polarization sensitivity and broadband efficiency was fabricated as well as a slit assembly with black (etched) silicon surface to minimize backscatter. First flight results over calibration sites as well as Monterey Bay in California have demonstrated good agreement between in situ and remotely sensed data, confirming the potential value of the sensor to the coastal ocean science community.

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