Photonics & Imaging

Light modulators of a proposed type would exploit the propagation of lightin "whispering-gallery" electromagnetic modes in microspheres made of electro-optical materials. These modulators would offer advantages of ultrahigh modulation efficiency and increased bandwidth, relative to their...

Thin-walled structures made of strong glassy nickel and glassy nickel-cobalt alloys, with tailorable low residual stresses, and with high resistance to permanent plastic deformation, can be formed by use of an electrodeposition process. This process was developed to enable the fabrication of lightweight,...

Modifications have been made to upgrade the system described in "Optoelectronic Particle-Fallout Sensor" (KSC-11687), NASA Tech Briefs, Vol. 19, No. 4 (April 1995), page 17a. A description of the unmodified version of the system is necessary to place a description of the modifications in context:

In a proposed technique of maskless gray-scale x-ray lithography, a photoresist to be patterned would be exposed to a parallel beam of hard x-rays. As explained below, the photoresist would be translated across the beam at a varying rate to effect one-dimensional spatial variations in the radiation dose...

Focal-plane electronic image sensors that would not saturate when exposed to intense illumination have been proposed. These sensors could be used to acquire accurate, scientific-quality data on images (including spectral images), even when the images contain both very bright and very dark areas. The proposed...

Two reports present additional information on the subject matter of "Software for Processing Data in Particle-Image Velocimetry" (LEW-16857),NASA Tech Briefs, Vol. 24, No. 1 (January 2000), page 26a. Like the cited prior article, both reports discuss the principles and the practical aspects of...

A proposal for development of a class of high-transmission and antireflection optical filters is derived from the observation that the eyes of moths reflect almost no light, regardless of the wavelength or the angle of incidence of illumination. The low-reflection property of moth eyes...