Peter A. Torpey

Double‐carrier injection and recombination in insulators, including diffusion effects

A theory describing the double‐carrier injection and recombination in thin insulating crystals is developed and applied to the case of current flow in anthracene. The diffusion‐free analysis indicates that the scaling J∝V2/d3 holds, even when recombination effects are present for any crystal thickness. The same scaling is shown to be valid when diffusion effects are present, if the injecting contacts are not limiting. The individual effects of recombination, diffusion, contacts, and crystal thickness are studied and discussed.

A nonlinear theory for describing the propagation of disturbances on a capillary jet

The problem of the growth of disturbances on a capillary jet has received much attention in the past. However, previous theories have produced only limited correlation with experimental evidence. Traditional perturbation approaches to the problem are not well suited to describing the highly nonlinear behavior of disturbances on a capillary jet, especially near the tip of the jet where it breaks up into isolated drops. On the other hand, numerical solutions necessitate the use of an extremely fine spatial resolution over a large extent to follow disturbances as they progress along the jet and grow in amplitude over several orders of magnitude. In this paper, a new approach to this well‐studied problem is described. The new approach is based on a weighted residual technique and takes advantage of the particular strengths of both analytical and numerical methods. The method is shown to correctly predict many of the nonlinear phenomena observed on actual jets and offers some fresh insight into the dynamical p...

Multipass printing in an ink-jet device

This paper discusses the use of multi-pass print modes in an ink-jet device. Multi-pass printing techniques are a class of pixel timing/sequencing methods that are associated with many commercial ink-jet printers. When these techniques are used, only part of the final printed image is actually printed during each pass of the printhead over the substrate. After a sufficient number of passes of the printhead over the substrate, the entire final image is printed. There are a variety of algorithms to decide how the image is built up after each successive pass of the printhead. The particular algorithm used will depend on the output results desired from the printer. The following sections will illustrate how these methods are commonly applied to offer enhanced printer capabilities, improve print quality, and increase systems tolerances and latitudes.