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We present the results of a modification performed in the optical system of the 62 cm telescope (f/14.32) at observatory “Severo Diaz Galindo” Universidad de Guadalajara, Mexico. This modification consists of a change of distance between the primary and secondary mirrors from 1020 to 1135 mm. With this, a change in the image plane from 5200 mm to 600 mm, measured from the vertex of the primary mirror, is obtained. The latter allow to get the first astronomical images of The Telescope. This modification was necessary because alignment errors, such as distance between primary and secondary mirrors in the original system were presented. Besides, the telescope has a new accurate and adequate mechanical system installed on November 2011. Details and the first images obtained, are here presented.

A 150 km free-space optical (FSO) communication link between Maui (Haleakala) and Hawaii (Mauna Loa) was demonstrated by JHU/APL and AOptix Technologies, Inc. in September 2006. Over a 5 day period, multiple configurations including single channel 2.5 Gbps transmission, single channel 10 Gbps, and four wavelength division multiplexed (WDM) 10 Gbps channels for an aggregate data rate of 40 Gbps were demonstrated. Links at data rates from 10 to 40 Gb/s were run in excess of 3 contiguous hours. Data on the received power, frame synchronization losses, and bit error rate were recorded. This paper will report on the data transfer performance (bit error rates, frame synchronization issues) of this link over a 5 day period. A micropulse lidar was run concurrently, and on a parallel path with the FSO link, recording data on scattering loss and visibility. Comparisons between the state of the link due to weather and the data transfer performance will be described.

This paper describes the results of an experi ment where an FSO link was established between a ground terminal and an airborne terminal on a tethered aerostat. In the first part of the experiment, four 10 Gb/s WDM channels were transmitted from the aerostat to the ground terminal, demonstrating error -free performance over many 5 minute windows. In the second part of the experiment, both one and two WDM channels, each running at a native 40 Gb/s rate, were transmitted over the FSO link, demonstrating error free performance over short (30 second) timeframes, and bit error rates in the 10 -6 range over longer term operation. During all tests, a 1 Gb/s optical Ethernet channel was run on a separate WDM channel. The paper will describe the test con figuration as well as the results when running both single and multiple channels. The im pact of the overall system design used for this experiment on the link integrity will be analyzed and discussed. It was found that the spatial dyna mics of the aerostat as a function of time of day had an impact on the quality of the link – this will also be di scussed. Modeling of poten tial penalty sources will also be discussed. Keywords: Free-space optical communications, wavelength division multiplexing, optical amplifier, noise figure

A free-space optical (FSO) communication demonstration was conducted with JHU/APL and AOptix at the TCOM Test Facility in Elizabeth City, NC in May 2006. The primary test objective was to evaluate the performance of an FSO link from a fiber-tethered aerostat to a ground platform at effective data rates approaching 100 Gigabits/sec using wavelength division multiplexing (WDM) techniques. (Multiple optical channels operating near 1550 nm were modulated at data rates of 1, 10 and 40 Gbps). The test was conducted with a 38 meter aerostat raised to an altitude of 1 km and a ground platform located 1.2 km from the aerostat (limited by property boundary). Error free data transfers of 1.2 Terabits in 30 seconds at 40 Gbps were demonstrated. The total data transferred during the test was greater than 30 Terabits with an average BER of 10 -6 without any forward error correction (FEC) coding.

The advent of large focal planes requiring many signal channels has exacerbated the problems associated with guaranteeing detector controller performance. The performance specifications for large focal plane controllers includes both 'per channel' requirements such as noise, linearity, dynamic range, etc. and 'system' requirements such as channel cross talk, gain matching, etc. To assess these performance parameters and fully characterize the controller before integration to a focal plane, the MONSOON team has adopted a testing methodology that is based on industry standard practices. This adoption has provided a consistent testing method that produces repeatable results and allows full characterization of the controller performance. This approach will provided a tool to assist in predicting focal plane performance before integration and establishes base line performance values for subsequent detector optimization efforts.

Imaging systems such as the Computed Tomographic Imaging Spectrometer (CTIS) are modeled by the matrix equationg = Hf , which is the discretized form of the general imaging integral equation.. The matrix H describes the contributionto each element of the image g from each element of the hyperspectral object cube f. The vector g is the image of thespatial/spectral projections of f on a focal plane array (FPA). The matrix H is enormous, sparse and rectangular. It isextremely difficult to discretize the integral operator to obtain the matrix operator H .NormallyH is constructedempirically from a series of monochromatic calibration images, which is a time consuming process. However we havebeen able to synthetically construct H by numerically modeling how the optical and diffractive elements in the CTISproject monochromatic point source data onto the FPA. We can evaluate a CTIS system by solving the imagingequation for f using both the empirical and synthetic H from some test data g. Comparison between the two resultsprovides a means to evaluate and improve CTIS system calibration procedures noting that the synthetic system matrix Hrepresents a baseline ideal system.Keywords: Hyperspectral Imaging, Tomographic Imaging Systems, Diffractive Optics

We have constructed a computed-tomography imaging spectrometer (CTIS) that uses two crossed phase-only computer generated holograms (CGH) as the dispersing elements. This imaging spectrometer collects the multiplexed spatial and spectral data simultaneously and can be used for flash spectral imaging. Previous CTIS instruments require a single CGH dispersing elements which were designed with the freedom of adjusting each element in the cell profile independently during the design process. The CHGs for this instrument are designed as identical crossed gratings to model the design parameters of a crossed 1D addressable liquid crystal spatial light modulator. Future integration of a liquid crystal spatial light modulator allows for the possibility of optical preprocessing of tomographic images. The CGH disperser pair has been designed to maintain nearly equal spectral diffraction efficiency among a 5x5 array of diffraction orders and to minimize the diffraction efficiency into higher orders. Reconstruction of the (x,y,(lambda) ) image cube from the raw, two-dimensional data is achieved by computed-tomography techniques.

Channeled spectropolarimetry is a technique for measuring the spectral dependence of the polarization state of light. Passive polarization optics are used to encode the spectral dependence of the four Stokes components s k into a single irradiance spectrum. We treat the technique as a linear operator and compute its singular value decomposition numerically. The resulting singular functions divide into three distinct groups representing s 0 , s 1 and mixtures of s 2 and s 3 . The corresponding singular values indicate that measurements of the latter two groups will have signal-to-noise ratios reduced form that of s 0 by factors of 0.6 and 0.4 respectively. The structure of the singular vectors is in agreement with a separate estimate of the system's resolution.

Figures of merit for optimization of a complete Stokes polarimeter based on its measurement matrix are described which are not limited in their application to cases in which four measurements are used in the determination of a single Stokes vector. Singular value decomposition and probability theory are used to investigate the behavior and significance of these figures of merit. Their use to optimize a system consisting of a rotatable retarder and fixed polarizer indicates that a retardance of 132° (approximately three-eighths wave) and retarder orientation angles of ±51.7° and ±15.1° are favorable when four measurements are used. The performance of this system is demonstrated with experimental data.

We report results of experimentation with a MWIR non-scanning, high speed imaging spectrometer capable of simultaneously recording spatial and spectral data from a rapidly varying target scene. High speed spectral imaging was demonstrated by collecting spectral and spatial snapshots of filtered blackbodies, combustion products and a coffee cup. The instrument is based on computed tomography concepts and operates in a mid-wave infrared band of 3.0 to 4.6 micrometer. Raw images were recorded at a video frame rate of 30 fps using a 160 X 120 InSb focal plane array. Reconstructions of simple objects are presented.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In the largely unpolarized natural IR environment, water stands out as a notably polarized source. Water surfaces appear partially polarized in the IR through both reflection and emission. This polarization can be significant in environmental and military remote sensing applications where the water is either the intended source or possibly a false target. In this paper we show and interpret measurements in midwave and longwave IR bands. The midwave images show up to 7 percent s polarization in regions where warm objects reflect from the water. The longwave data also show s polarization in regions of sunglint, but elsewhere exhibit p polarization. Where the background is clear sky, the longwave signal is p polarized by up to 5 percent at large incidence angles.

We describe fluorescence spectral-imaging results with the microscope computed-tomography imaging spectrometer ((mu) CTIS). This imaging spectrometer is capable of recording spatial and spectral data simultaneously. Consequently, the (mu) CTIS can be used to image dynamic phenomena involving multiple, spectrally overlapping fluorescence probes. The result presented in this paper consists of proof-of-concept imaging result using two static targets. The first is composed of 6-micrometers fluorescing microspheres and the second consists of rat sinusoid epithelial cells loaded with 0.5-micrometers fluorescing microspheres. Image data were collected in integration times of 16 msec, comparable to video frame rate integration times. The emission spectra were sampled at 10-nm intervals between 420 nm and 710 nm. The smallest spatial sampling interval presented in this paper is 1.7 micrometers .

Uncooled indium antimonide (InSb) photoconductors were studied to determine their primary noise source, spectral response, and maximum attainable spectral detectivity. The dominant noise component was determined by theoretically analyzing the background photon generation- recombination noise, thermal generation-recombination noise, and Johnson noise, using conditions of the experimental setup. It was shown that at room temperature (300 K) Johnson noise was predominant. Using this fact, an expression was derived for spectral detectivity which gave a value of 1.3 X 108 cm-Hz1/2/watt for a 25.2 k(Omega) photoconductor and 5.9 X 108 cm-Hz1/2/watt for a 10 k(Omega) photoconductor. The measurements from the experiment showed a peak wavelength response at 5 micrometer and a cutoff wavelength (50% of maximum) at 5.5 micrometer. The average peak spectral detectivity for the 25.2 k(Omega) photoconductor was 1.17 X 108 cm- Hz1/2/watt and for the 10 k(Omega) photoconductor, 4.48 X 108 cm- Hz1/2/watt. These results compared well with theory.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.