Pushing the limits

Manufacturers of large-area imagers are pushing the limits of size and sensitivity as they rise to the challenge posed by ­ high-end imaging applications that range from medicine to astronomy. In the first article in this Optoelectronics World supplement devoted to imaging, Alice Reinheimer highlights the challenges of large-area imaging and explains how the imagers are growing to meet these specialized requirements. And while the devices themselves are getting larger, so too are the focal- plane arrays into which the devices are combined. One of the largest of these arrays-containing no less than 40 CCDs-now sits atop Mauna Kea in Hawaii.

As the imagers gain in sophistication, so too must the complexity of the hardware and software that process their output. Large arrays like the one atop Mauna Kea produce huge amounts of image data (50 terabytes over five years) that must be processed and stored-something that would not have been feasible a few years back. And smaller imagers, while producing much less actual data, can still challenge the processors. Dedicated imaging systems, for example, can help a computer make decisions based on what they “see” combined with sophisticated processing algorithms. In the second article, Gary Pedeville discusses segmentation algorithms for image-based automated defect detection during the manufacture of flat-panel displays.

The third feature highlights the research of Arthur R. Weeks and colleagues at the University of Central Florida in nonlinear filtering of color images, which is more complex than nonlinear filtering of grayscale images. In nonlinear filtering each pixel in a color image is viewed as a three-dimensional vector and the article describes the development of a set of morphological operators to order the vector data.