A miniature confocal Raman probe for endoscopic use.

Raman spectroscopy is a powerful tool for studying biochemical changes in the human body. We describe a miniature, confocal fibre optic probe intended to fit within the instrument channel of a standard medical endoscope. This probe has been optimized for the study of the carcinogenesis process of oesophageal malignancy. The optical design and fabrication of this probe is described including the anisotropic wet etching technique used to make silicon motherboards and jigs. Example spectra of PTFE reference samples are shown. Spectra with acquisition times as low as 2 s from resected oesophageal tissue are presented showing identifiable biochemical changes from various pathologies.