We propose development of innovative optics for a slide scanner to generate virtual slides in histopathology. These optics will allow scanning a microscope slide in a single sweep at a numerical aperture of NA = 0.65, covering the entire width and length of a slide with 0.5-mu sampling. The innovation consists of the use of an array of miniaturized objectives, each measuring approximately 2 mm in diameter and 10 mm in length, slightly staggered in the array, to produce a single, seamless sweep of the slide. The proposed innovation allows very rapid scanning, requiring less than 60 seconds for a full microscope slide of 20 mm x 50 mm, at diffraction-limited sampling. Specialized diagnostic expertise is expensive and frequently difficult to find. Therefore, materials are increasingly evaluated by telepathology, i.e., by sending digitized imagery from a remote location to a centralized diagnostic facility. Unfortunately, scanning of histopathologic slides is still very time-consuming. The parallelization of image acquisition by means of the array microscope results in a gain in scanning speed by a factor of 15-20 over any single-objective system. Furthermore, the array-microscope solution reduces the computational burden that is required in stitching of image tiles or swaths used in conventional scanning systems. The innovation further resides in an optics design based on injection-molded plastic aspheric lens elements, generated in large numbers on separate plates for each element. By stacking up the plates bearing the lens elements for the objectives, the array of microscope objectives is assembled fully in parallel.
