Open AccessDivided-aperture confocal Brillouin microscopy for simultaneous high-precision topographic and mechanical mapping
Author(s) -
Hanxu Wu,
Weiqian Zhao,
Yunhao Su,
Lirong Qiu,
Yun Wang,
He Ni
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.405458
Subject(s) - optics , materials science , brillouin zone , confocal microscopy , confocal , microscopy , characterization (materials science) , microscope , aperture (computer memory) , brillouin scattering , numerical aperture , laser , nanotechnology , physics , acoustics , wavelength
Confocal Brillouin microscopy (CBM) is a novel and powerful technique for providing non-contact and direct readout of the micro-mechanical properties of a material, and thus used in a broad range of applications, including biological tissue detection, cell imaging, and material characterization in manufacturing. However, conventional CBMs have not enabled high precision mechanical mapping owing to the limited depth of focus and are subject to system drift during long-term measurements. In this paper, a divided-aperture confocal Brillouin microscopy (DCBM) is proposed to improve the axial focusing capability, stability, and extinction ratio of CBM. We exploit high-sensitivity divided-aperture confocal technology to achieve an unprecedented 100-fold enhancement in the axial focusing sensitivity of the existing CBMs, reaching 5 nm, and to enhance system stability. In addition, the dark-field setup improves the extinction ratio by 20 dB. To the best of our knowledge, our method achieves the first in situ topographic imaging and mechanical mapping of the sample and provides a new approach for Brillouin scattering applications in material characterization.