NIST and two industrial partners have developed a new high-resolution image acquisition and analysis system that may be retrofitted to most existing scanning electron microscopes to substantially improve the quality and detail of SEM images. (See tin particles above.)

The system, named ISAAC, digitizes the collected SEM signal with a resolution up to 4096 by 4096 pixels. Many commercial SEMs generate images with much lower resolution, often 512 or 1024 pixels across. At the same time, ISAAC provides a much greater range of measured values for each pixel. The system replaces the 8-bit image-processing system provided in most commercial SEM's with a 16-bit system. As a result, ISAAC produces more than 65,000 intensity levels in the final image, compared to ony 256 levels available with most image-processing systems.

ISAAC also provides researchers with greater flexibility for data analysis, storage, and retrieval. It can be used to produce "movies" of dynamic processes, make dimensional measurements, count and analyze particles, and automate micrograph analysis.

Developed in collaboration with 4pi Analysis Inc., Durham, N.C., and Signal Analytics Corp., Vienna, Va., the system includes hardware tht improves control of SEM's electron beam so that more accurate data may be collected from a sample.

The system runs on a desk-top computer and was originally developed to analyze over 1,000 micrographs and SEM data from 35 different laboratories participating with NIST in an interlaboratory study of a prototype SEM magnification standard.

Contact: Michael Postek, (301) 975-2299.