Design of a Scanning Optical Microscope for Simultaneous Large Field of View and High Resolution

In microsystems applications from micro-assembly to biological observation and manipulation, the optical microscope remains one of the most important tools. However, it suffers from the well known trade-off between resolution and field of view. Traditional solutions involve moving the sample under the microscope using a moving stage or moving the microscope itself, and switching between low and high magnification objective lenses. In this paper, we present a new optical microscope design that uses a 2-dimensional high speed, high precision steering mirror system to scan the sample. By stitching the images together as a mosaic, we have the potential to achieve both high resolution and large field of view. An experimental prototype has been constructed to demonstrate the basic efficacy of the concept. However, in order to further improve the performance, systematic design of the optical, motion, and image acquisition subsystems is needed. We present the design constraints and performance metrics, and pose the design as a multi-objective optimization. By using a commercial optical design package, we show that it is possible to adjust the optical system parameters to improve specific performance measures.