Ultrahigh resolution spectral-domain optical coherence tomography at 1.3 μm using a broadband superluminescent diode light source

Abstract

We present an ultrahigh resolution spectral-domain optical coherence tomography imaging system using a broadband superluminescent diode light source emitting at a center wavelength of 1.3 µm. The light source consists of two spectrally shifted superluminescent diodes that are coupled together into a single mode fiber. The effective emission power spectrum has a full width at half maximum of 200 nm and the source output power is 10 mW. The imaging system has an axial resolution of 3.9 µm in air (< 3.0 µm in biological tissue), and a lateral resolution of 6.5 µm. The sensitivity and the maximum line rate are 95 dB and 46 kHz, respectively. Images of an infrared viewing card and a cornea from human eye suffering from glaucoma showing Schlemm's canal are presented to illustrate the performance of the system.

Numerical Analysis of Supercontinuum Generated Microstructured Optical Fiber with all Normal Chromatic Dispersion

“…The achieved input powers are 1.6 kW at 1.06 μm center wavelength, 2.4 kW at 1.30 μm center wavelength and 3.8 kW at 1.55 μm center wavelength; with acquired fiber length LF of 6 m for all center wavelengths considered. These Pin values are higher and LF values are lower than those reported light sources in references[7][8][9][10][11][12][13].…”

“…Moreover, the proposed M-PCF exhibits an ultra-flattened chromatic dispersion of 0.0 ~ -4.5 ps/(nm.km) and broad supercontinuum spectrum in the targeted wavelength range, making it suitable for optical transmissions and SC generation applications. The proposed M-PCF also exhibits high power and short fiber length at center wavelength 1.06 μm, 1.30 μm and 1.55 μm, which are superior to that in references [7][8][9][10][11][12][13].…”

“…Generation of SC spectrum with 80 nm bandwidth and 2 mW to 15 mW output power centered at approximately 1.2 μm wavelength have been demonstrated by Shibita et al [7]. Bayleyegn et al [8] produced an SC spectrum with 200 nm full width at half maxima and 10 mW source output power centered at 1.3 μm wavelength. These output powers are, however, insufficient for the identification of individual cells [7].…”

“…High nonlinear coefficient is also crucial for the generation of supercontinuum (SC) spectrum. Till now, super-luminescent diodes (SLDs) [7,8], femtosecond pulse laser sources [9][10][11][12] and picosecond pulse laser source [13] have been investigated as broadband light sources. Generation of SC spectrum with 80 nm bandwidth and 2 mW to 15 mW output power centered at approximately 1.2 μm wavelength have been demonstrated by Shibita et al [7].…”

“…These output powers are, however, insufficient for the identification of individual cells [7]. Furthermore, multiplexed SLD light sources were used; with complex designs but low output power [8]. Zaytsev et al [9] reported an SC spectrum pumped with 200 fs Yb-doped fiber laser at central wavelength of 1.07 μm, to obtain 11 nm spectrum FWHM and 800 mW output power.…”