Label-free imaging of thick tissue at 1550 nm using a femtosecond optical parametric generator

Label-free imaging of thick tissue at 1550 nm using a femtosecond optical parametric generator.

We have developed a simple wavelength-tunable optical parametric generator (OPG), emitting broadband ultrashort pulses with peak wavelengths at 1530-1790 nm, for nonlinear label-free microscopy. The OPG consists of a periodically poled lithium niobate crystal, pumped at 1064 nm by a ultrafast Yb:fiber laser with high pulse energy. We demonstrate that this OPG can be used for label-free imaging,...

Optical fiber link for transmission of 1-nJ femtosecond laser pulses at 1550 nm.

We report on numerical and experimental characterization of the performance of a fiber link optimized for the delivery of sub-100-fs laser pulses at 1550 nm over several meters of fiber. We investigate the power handling capacity of the link, and demonstrate all-fiber delivery of 1-nJ pulses over a distance of 5.3 m. The fiber link consists of dispersion-compensating fiber (DCF) and standard si...

Optical coherence microscopy in 1700 nm spectral band for high-resolution label-free deep-tissue imaging

Optical coherence microscopy (OCM) is a label-free, high-resolution, three-dimensional (3D) imaging technique based on optical coherence tomography (OCT) and confocal microscopy. Here, we report that the 1700-nm spectral band has the great potential to improve the imaging depth in high-resolution OCM imaging of animal tissues. Recent studies to improve the imaging depth in OCT revealed that the...

Nonlinearities in porous silicon optical waveguides at 1550 nm.

We report an experimental investigation of the nonlinear optical properties of nanoporous silicon optical waveguides measured at 1550 nm. The nonlinear properties including two-photon absorption, self-phase modulation, free-carrier absorption and free-carrier plasma dispersion are characterized and compared with similar measurements conducted on a conventional silicon-on-insulator ridge wavegui...

Optical Absorption of Silicon Nitride Membranes at 1064 nm and at 1550 nm