Dual Axes Confocal Microscopy

This chapter describes the theory, design, and implementation of a novel confocal architecture that uses separate optical axes for illumination and collection of light. This configuration can achieve subcellular resolution (< 5 mu m) with a deep tissue penetration (> 500 mu m) and a high dynamic range. Moreover, a large field-of-view can be generated with a diffraction-limited focal volume using post-objective scanning that also allows for this configuration to be scaled down in size to millimeter dimensions without loss of performance. Endoscope compatibility can be achieved with use of a MEMS (micro-electro-mechanical systems) scanner and fiber coupling. An instrument of this size can be used to perform real-time histopathology from the epithelium of hollow organs and longitudinal studies in small animals.