A Photon Counting Imager

The Remote Low Light Imaging (RULLI) system responds to individual photons using a modification to conventional image intensifier technology and fast timing electronics. Each photon received at the detector is resolved in three dimensions (X, Y, and time). The accumulation of photons over time allows the system to image with very low light levels, such as starlight illumination. Using a low power pulsed laser and very fine time discrimination, three dimensional imaging has been accomplished with a vertical resolution of five cm

Demonstration of Literal Three-Dimensional Imaging

In a recent paper a new technique was proposed for remote ranging and topographical mapping by using a system with a single-photon-counting detector and a low-power pulsed laser @Appl. Opt. 35, 441 ~1996!#. We report on the results from the laboratory and the field demonstration of this literal three-dimensional imaging technique. Using a detector system developed at Los Alamos with a commercial pulsed laser and observing from a single remote vantage point, we demonstrate use of this technique in the literal mapping of three-dimensional topography and the probing of a complex scene. With a reasonably short exposure this system can resolve features with height variations as small as 5 cm. © 1999 Optical Society of Americ

The association between preschool children's social functioning and their emergent academic skills

This study examined the relationship between social functioning and emergent academic development in a sample of 467 preschool children (M = 55.9 months old, SD = 3.8). Teachers reported on children’s aggression, attention problems, and prosocial skills. Preliteracy, language, and early mathematics skills were assessed with standardized tests. Better social functioning was associated with stronger academic development. Attention problems were related to poorer academic development controlling for aggression and social skills, pointing to the importance of attention in these relations. Children’s social skills were related to academic development controlling for attention and aggression problems, consistent with models suggesting that children’s social strengths and difficulties are independently related to their academic development. Support was not found for the hypothesis that these relationships would be stronger in boys than in girls. Some relationships were stronger in African American than Caucasian children. Children’s self-reported feelings about school moderated several relationships, consistent with the idea that positive feelings about school may be a protective factor against co-occurring academic and social problems