Engineering topics
Publications and source records attributed to Maker, P. D..
A key element in the Eclipse coronagraph is the apodized occulting spot. For exo-planet detection in the presence of a sun-like star, the intensity transmittance at the center of the spot is specified to be less than 1X10***sup-8***.
High power 2.05-mu m Fabry-Perot and distributed feedback (DFB) ridge waveguide lasers fabricated from epitaxially grown InGaAsSb/AlGaAsSb/GaSb and InGaAs/InP hetero-structures are reported.
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Calculations of the grating spatial-frequency spectrum and the filtering properties of multiple-pass electron-beam writing demonstrate a tradeoff between stitching-error suppression and minimum pitch separation. High-resolution measurements of optical-diffraction patterns show a 25-dB reduction in stitching-error side modes.
The coherent Doppler lidar approach for acquiring global profilometry of tropospheric winds from Earth orbit is reliant on off-nadir beam scanning geometry for retrieval of vector winds by Doppler analysis of laser radiation backscattered by entrained aerosols and cloud particles.
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Frequency selective surfaces are widely used in the microwave and millimeter wave regions of the spectrum for filtering signals. They are used in telecommunication systems for multi-frequency operation or in instrument detectors for spectroscopy.
In this paper, we discuss the development of very sensitive long wavelength infrared GaAs/AlxGa1-xAs quantum well infrared photodetectors (QWIPs) based on bound-to-quasibound intersubband transition, fabrication of light coupling schemes for efficient light coupling, and demonstration of several long wavelength infrared cameras based on QWIP focal plane arrays.
The properties of convex gratings fabricated by electron-beam lithography are investigated. Three grating types are shown. These gratings allow the optical designer to fully realize the considerable advantages of concentric spectrometer forms.
The performcance of this QWIP camera is reported including indoor and outdoor imaging.
The performance of this QWIP camera is reported including indoor and outdoor imaging.
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In this paper, we discuss the development of this very sensitive long wavelength infrared (LWIR) camera based on a GaAs/AlGaAs QWIP focal plane array (FPA) and its performance in quantum efficiency, NE(delta)T, uniformity, and operability.
The computed-tomography imaging spectrometer (CTIS) captures a scene's spatial and spectral information without any type of scanning.
In this paper, we discuss the development of this very sensitive long waelength infrared (LWIR) camera based on a GaAs/AlGaAs QWIP focal plane array (FPA) and its performance in quantum efficiency, NEAT, uniformity, and operability.
A hand-held quantum well infrared photodetector camera has been demonstrated.
A 9 micrometers cutoff 640 x 484 hand-held quantum well infrared photodetector (QWIP) camera has been demonstrated. Excellent imagery, with a noise equivalent differential temperature (NE.deltaT) of 43 mK has been achieved. In this paper, we discuss the development of this very sensitive long wavelength infrared (LWIR) camera based on a GaAs/AlGaAs QWIP focal plane array (FPA) and its performance in quantum efficiency, NE.deltaT, uniformity, and operability.
In this paper, we discuss the development of very sensitive long wavelength infrared (LWIR) GaAs/AlxGa1-xAs quantum well infrared photodetectors (QWIPs), fabrication of random reflectors for efficient light coupling, and the demonstration of first hand-held long-wavelength 256x256 QWIP focal plane array camera. Excellent imagery, with a noise equivalent differential temperature of 25 mK has been achieved.