Microorganism Tracking Microscope System

Continuous observation of individual motile microorganisms is difficult, since their swimming speed is fast compared with their diameters. In fact, some bacteria can swim as fast as 50 diameters/s [1]. At this speed, microorganisms can quickly go out of the range of static measurement instruments, such as the field of view of optical microscopes. This problem can be solved by tracking the microorganism within the field of view by moving the chamber of the microorganism. In principal, this tracking can be realized by visual feedback control using a vision system mounted on the microscope. In this method, the position of the chamber is controlled based on the visual information captured by the vision system so as to keep the target within the field of view. This method allows continuous observation with high resolution and can be used with various imaging techniques by modifying its image-processing program. However, conventional vision systems, such as CCDs, operate at standard video rates (30 Hz for NTSC or 24 Hz for PAL) are too slow for this application. Therefore, a vision system with high frame rate is essential for the tracking of microorganisms.