BIOMEDICAL ARTICLES
Heiligenschein and related phenomena in divergent light.
When seen in divergent light, atmospheric optical phenomena could appear to be modified. We describe some geometric and retroreflectional effects of light divergence on heiligenschein and related phenomena that, to our knowledge, have not been previously reported. These geometric effects are compared with and set in […]
Correction of Sun glint Contamination on the SeaWiFS Ocean and Atmosphere Products.
For remote sensing of the ocean and atmosphere optical properties, the measurement of radiances affected by sun glint has to be avoided and/or masked out. There are usually no meaningful retrievals in regions significantly contaminated by sun glint. The Sea-viewing Wide […]
Strong dependence of rain-induced lidar depolarization on the illumination angle: experimental evidence and geometrical-optics interpretation.
Backscatter and depolarization lidar measurements from clouds and precipitation are reported as functions of the elevation angle of the pointing lidar direction. We recorded the data by scanning the lidar beam (Nd:YAG) at a constant angular speed of […]
Wavelength Dependence of Backscatter by use of Aerosol Microphysics and Lidar Data Sets: Application to 2.1- mum Wavelength for Space-Based and Airborne Lidars.
An aerosol microphysics dataset was used to model backscatter in the 0.35-11-mum wavelength range, with the results validated by comparison with measured cw and pulsed lidar backscatter obtained during two […]
Characterization of Two-Dimensional finite-aperture wire Grid Polarizers by a Spectral-Domain Technique.
We investigate the transmission characteristics of perfectly conducting two-dimensional wire grid polarizers fabricated in finite and infinite apertures using a rigorous spectral-domain mode-matching method. Specifically, the transmission coefficient for both transverse-electric and transverse-magnetic polarizations, extinction ratio, and diffraction pattern are characterized for […]
Scattering Measurements on Optical Disks and their Relation to Media Noise.
We have conducted measurements of scattered light from bare polycarbonate and glass substrates and from complete optical disks using a He-Ne laser beam in different polarization states and at different angles of incidence. The results are compared with the measured media noise […]
Improvement in holographic storage capacity by use of double-random phase encryption.
We show that a double-random encryption technique can improve the storage capacity of an angular-multiplexed holographic memory system. In the holographic memory system, input binary images are encrypted into white-noise-like images by use of two random phase masks located at the input […]
Experimental Study on Nonuniformity of Line Jitter in CCD Images.
The line jitter of CCD images can considerably influence the precision and resolution of a high-accuracy vision-based automated inspection system. We report the experimental studies on the line jitter of CCD images. By use of a method of Harr wavelet transform, correlation, and […]
Enhanced-resolution image restoration from a sequence of low-frequency vibrated images by use of convex projections.
An algorithm to increase the spatial resolution of digital video sequences captured with a camera that is subject to mechanical vibration is developed. The blur caused by vibration of the camera is often the primary cause for image […]
Near-field artifact reduction in planar coded aperture imaging.
Coded apertures for imaging problems are typically based on arrays having perfect cross-correlation properties. These arrays, however, guarantee a perfect point-spread function in far-field applications only. When these arrays are used in the near-field, artifacts arise. We present a mathematical derivation capable of predicting the […]