A color scanning Digital Microscope: A new tool for Telepathology
This paper provides an evaluation of the COSMIC digital microscope, a cameraless white light-scanning microscope useful for providing rapid, high quality images using a traditional bright field microscope base. The instrument based on a Zeiss Axiovert scope using 2.5, 10, 40 and 100x infinity corrected objectives uses standard photomultiplier tubes (pmt) for detectors. Each detector collects a fixed bandwidth of light (300-490; 500-600; >600 nm via optical filters. There are five unique aspects of the microscope that should be noted. 1. The light source is a CRT oscilloscope providing 13.8 images per second, 2. The detectors are PMTs, 3. The instrument contains a 3 x electronic zoom that does not require changing of objectives, 4. There are extensive image processing options available directly on the scope, 5. Images are saved directly over the Internet via 10 Base10 cable as TIF files. The microscope collects images as 1280 x 1024 pixel images in 24 bit. Since there are no moving parts on the microscope there is no alignment issues, and no camera or computer compatibility issues to deal with. The microscope has no ocular - however because of the optical path, none is required to find or focus the specimen. Because of the light path, it is necessary to ensure proper Kohler illumination to obtain sharp well-focused images. Presented are a series of images collected with high cost, and low cost color cameras compared with the COSMIC scope images. Also presented are the many variations of image processing available in the system, which allow for electronic versions of dark field, color reversal and gamma and contrast enhancements.