Miniature objective lens with variable focus for confocal endomicroscopy

作者:Kim Minkyu*; Kang DongKyun; Wu Tao; Tabatabaei Nima; Carruth Robert W; Martinez Ramses V; Whitesides George M; Nakajima Yoshikazu; Tearney Guillermo J
来源:Biomedical Optics Express, 2014, 5(12): 4350-4361.
DOI:10.1364/BOE.5.004350

摘要

Spectrally encoded confocal microscopy (SECM) is a reflectance confocal microscopy technology that can rapidly image large areas of luminal organs at microscopic resolution. One of the main challenges for large-area SECM imaging in vivo is maintaining the same imaging depth within the tissue when patient motion and tissue surface irregularity are present. In this paper, we report the development of a miniature vari-focal objective lens that can be used in an SECM endoscopic probe to conduct adaptive focusing and to maintain the same imaging depth during in vivo imaging. The vari-focal objective lens is composed of an aspheric singlet with an NA of 0.5, a miniature water chamber, and a thin elastic membrane. The water volume within the chamber was changed to control curvature of the elastic membrane, which subsequently altered the position of the SECM focus. The vari-focal objective lens has a diameter of 5 mm and thickness of 4 mm. A vari-focal range of 240 mu m was achieved while maintaining lateral resolution better than 2.6 mu m and axial resolution better than 26 mu m. Volumetric SECM images of swine esophageal tissues were obtained over the vari-focal range of 260 mu m. SECM images clearly visualized cellular features of the swine esophagus at all focal depths, including basal cell nuclei, papillae, and lamina propria.

  • 出版日期2014-12-1