Piezoelectric scanning mirrors for endoscopic optical coherence tomography

• Published in: Journal of micromechanics and microengineering Vol. 19; no. 9; pp. 095012 - 095012 (11)
• Main Authors: Gilchrist, Kristin H, McNabb, Ryan P, Izatt, Joseph A, Grego, Sonia
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.09.2009; Institute of Physics
• Subjects: Applied sciences; Biological and medical sciences; Electronics; Endoscopy; Exact sciences and technology; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Investigative techniques, diagnostic techniques (general aspects); Mechanical engineering. Machine design; Mechanical instruments, equipment and techniques; Medical sciences; Microelectronic fabrication (materials and surfaces technology); Micromechanical devices and systems; Physics; Precision engineering, watch making; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Scanner; Optical scanners; Catheter; Endoscope; Optical beam; Optical measurement; Angular displacement; Forwarding; Resonance frequency; Piezoelectricity; Tomography; Endoscopy; Mirror; Micromirrors
• ISSN: 0960-1317; 1361-6439
• DOI: 10.1088/0960-1317/19/9/095012

A novel piezoelectric scanning mirror design for endoscopic optical coherence tomography (OCT) is presented. OCT is an interferometric technique providing microscopic tomographic sectioning of biological samples with mm-range penetration capability in tissue and is suited for integration with endoscopes using fiber-based light delivery to the sample. The piezoelectric scanning mirror was designed to provide wide-range rapid forwarding-looking scanning of the optical beam at the distal end of a compact catheter. The optical scanner provides a large ratio of mirror aperture to device size with rectangular mirror sizes ranging from 600 mum X 840 mum to 840 mum X 1600 mum. Static angular displacements up to +/-7 deg (mechanical angle) were demonstrated and resonance frequencies of hundreds of Hz (and up to 1-2 kHz) were measured, depending on the mirror size. The imaging capability of the piezoelectric scanner was demonstrated using a bench-top spectrometer-based Fourier-domain OCT system.