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The NGST Phase Retrieval Camera (PRC) is a portable wavefront sensor useful for optical testing in high-vibration environments. Primary applications of the PRC are testing and experimenting with NGST technology demonstrator mirrors, along with exploring other wavefront sensing and control problems not easily studied using WCT. An overview of the hardware and testing results will be presented.

This presentation will detail the packaging and hardware chosen for the PRC, the PRC software, and calibration of the instrument.

This paper describes recent modifications to the instrument over winter maintenance cycles not covered elsewhere, and discusses the rationale leading up to the changes, implementation and results.

This guide serves as a brief overview of the AVIRIS instrument and its role in the field of imaging spectrometry.

This paper presents key aspects of the implementation, operation, calibration, georectification, and validation of AVIRIS on a low-altitude platform in the Autumn of 1998.

AVIRIS is a calibrated Earth-looking imaging spectrometer that measures the total upwelling spectral radiance in the solar reflected spectrum for 400 to 2500 nm.

Imaging spectroscopy is of growing interest as a new approach to Earth remote sensing. The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) was the first imaging sensor to measure the solar reflected spectrum from 400 to 2500nm at 10 nm intervals.

The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) measures spectral radiance in the solar reflected spectrum from 400 to 2500 nm.

The trap or quantum efficient detector has a quantum effciency of greater than 0.98 for the region from 450 to 900nm.

The AVRIS On-Board Calibrator (OBC) provides essential data for refining the calibration of each AVIRIS data run.

To validate AVIRIS in flight, and in-flight calibration experiment was performed for an over-flight on May 9, 1995, at Ivanpah Playa, California, USA. In-situ measurements were used to constrain a radiative transfer code and predict the total upwelling spectral radiance incident at AVIRIS.

None given. From Intro: This paper describes AVIRIS (the Airborne Visible and InfraRed Imaging Spectrometer) as a remote sensing instrument that is supported, calibrated, and maintained by JPL.

An imaging spectrometer measures a contiguous spectrum of light for each spatial element of an image.

Teaching technical writing to Native Americans contending with a second language and culture is addressed. Learning difficulties arising from differences between native and acquired language and cultural systems are examined. Compartmentalized teaching, which presents the ideals of technical writing in minimal units, and skills development are considered. Rhetorical problems treated include logic of arrangement, selection of support and scope of detail, and time and space. Specific problems selected include the concept of promptness, the contextualization of purpose, interpersonal relationships, wordiness, mixture of registers, and the problem of abstracting. Four inductive procedures for students having writing and perception problems are included. Four sample exercises and a bibliography of 13 references are also included.

The effects of various machine design parameters on the growth of web dendritic silicon ribbon were investigated. Ribbons were grown up to lengths of one meter, with widths increasing linearly up to one cm at the point of termination of growth. Thermal data were collected and evaluated for actual seeding and growth with variations in parameters affecting heat loss. It was found that for suitable growth, the mechanical system should be very rigid and stable, and the tolerances and specifications of the quartz crucibles must be far tighter than normal quartz tolerances. The widening rates of the ribbons were found to be a function of the temperature gradient rather than the temperature differences alone. A twin spacing in the seed of 3 microns to 2 microns was found to be unfavorable for growth; whereas spacing of 0.9 microns to 2 microns and 8 microns to 2 microns were favorable. Thermal modeling studies of the effects of furnace design parameters on the temperature distributions in melt and the growth of the dendritic web ribbon showed that the pull rate of the ribbon is strongly dependent on the temperature of the top thermal shield, the spacing between this shield and the melt, and the thickness of the growing web.

A web furnace was constructed for pulling dendritic-web samples. The effect of changes in the furnace thermal geometry on the growth of dendritic-web was studied. Several attempts were made to grow primitive dendrites for use as the dendritic seed crystals for web growth and to determine the optimum twin spacing in the dendritic seed crystal for web growth. Mathematical models and computer programs were used to determine the thermal geometries in the susceptor, crucible melt, meniscus, and web. Several geometries were determined for particular furnace geometries and growth conditions. The information obtained was used in conjunction with results from the experimental growth investigations in order to achieve proper conditions for sustained pulling of two dendrite web ribbons. In addition, the facilities for obtaining the following data were constructed: twin spacing, dislocation density, web geometry, resistivity, majority charge carrier type, and minority carrier lifetime.

Electron microscopy analysis of microinhomogeneities in commercial Si used in preparation of p-n junction devices