Scanning optical mosaic scope for dynamic biological observations and manipulation

Abstract. Conventional microscopes with high magnification are limited by the size of the field of view. For biological observations and in particular for biological specimen manipulation, the need for a larger field of view has recently gained significant attention. For instance, for histological sections, specimens are rather large and need to be observed in their entirety with an high enough level of magnification. In cell biology, there is also a need for tracking multiple events occuring in a cell population and therefore, it is necessary to be able to look at different portions of a specimen at the same time. Enlarging the field of view has been done so far, by moving the specimen under the objectives. However, in general, the moving stage approach has two drawbacks: low-speed operation and time consuming calibration to gain accuracy. It also requires sophisticated, time consuming, vision processing algorithm to stitch grabbed images together. This paper introduces an alternate approach that consists in combining high speed scanners and a high speed camera to create a mosaic view over a large field of view at high refresh rates. We state the design problem of the optical, motion, and image processing subsystems and discuss the initial experimental setup and results. As a typical application, we emphasize the usefulness of this approach for cell population observations.