TY - JOUR
T1 - Signal enhancement by fiber-dispersion in sub-ghz frequency domain biophotonic diagnosis systems
AU - Tseng, Sheng Hao
AU - Huang, Tzu Feng
AU - Yeh, Jun Liang
AU - Chan, Ming Che
N1 - Funding Information:
Manuscript received February 21, 2018; revised April 11, 2018; accepted May 30, 2018. Date of publication June 11, 2018; date of current version June 27, 2018. This work was supported in part by the Department of Medical Research of Chi-Mei Medical Center and in part by the Ministry of Science and Technology (MOST), Taiwan, under Grants MOST-104-2221-E-009-155-MY3, MOST-103-2221-E-009-076, and MOST-104-2221-E-006-179-MY3. (Corresponding author: Ming-Che Chan.) S.-H. Tseng is with the Department of Photonics, National Cheng-Kung University, Tainan 701, Taiwan (e-mail:,[email protected]).
Publisher Copyright:
© 1995-2012 IEEE.
PY - 2018/1/1
Y1 - 2018/1/1
N2 - Pulsed lasers can be utilized to generate intensity-modulated light at the fundamental frequency of the laser repetition rate as well as higher order modulation (HOM) frequencies in the recent study. We also demonstrated the feasibility of using pulse lasers and fiber-wavelength-convertors as a light source in multicolor frequency-domain (FD) biophotonic systems. In this paper, we present a novel approach to enhancing the intensity of signals below 1 GHz in HOM-based FD systems simply by employing the fiber dispersion effect. The energy spectrum of HOMs can be redistributed to enhance the intensity of HOMs within the bandwidth of the photo-detector without the need for an external (optical or electrical) amplifier. We also demonstrate that the length of dispersive fiber can be optimized via numerical calculations, the results of which are in good agreement with experimental measurements. Finally, we demonstrate a frequency-domain-photon-migration system employing the fiber dispersion effect to enhance sub-GHz signals at a wavelength of 1.03 μm in order to recover the optical properties of turbid samples. Our measurements results demonstrate the superiority of the proposed FD source over the conventional directly modulated FD light source. Furthermore, the simple configuration of the proposed scheme makes it applicable to a wide range of FD biophotonic systems.
AB - Pulsed lasers can be utilized to generate intensity-modulated light at the fundamental frequency of the laser repetition rate as well as higher order modulation (HOM) frequencies in the recent study. We also demonstrated the feasibility of using pulse lasers and fiber-wavelength-convertors as a light source in multicolor frequency-domain (FD) biophotonic systems. In this paper, we present a novel approach to enhancing the intensity of signals below 1 GHz in HOM-based FD systems simply by employing the fiber dispersion effect. The energy spectrum of HOMs can be redistributed to enhance the intensity of HOMs within the bandwidth of the photo-detector without the need for an external (optical or electrical) amplifier. We also demonstrate that the length of dispersive fiber can be optimized via numerical calculations, the results of which are in good agreement with experimental measurements. Finally, we demonstrate a frequency-domain-photon-migration system employing the fiber dispersion effect to enhance sub-GHz signals at a wavelength of 1.03 μm in order to recover the optical properties of turbid samples. Our measurements results demonstrate the superiority of the proposed FD source over the conventional directly modulated FD light source. Furthermore, the simple configuration of the proposed scheme makes it applicable to a wide range of FD biophotonic systems.
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U2 - 10.1109/JSTQE.2018.2846054
DO - 10.1109/JSTQE.2018.2846054
M3 - Article
AN - SCOPUS:85048481201
SN - 0792-1233
VL - 25
JO - IEEE Journal of Selected Topics in Quantum Electronics
JF - IEEE Journal of Selected Topics in Quantum Electronics
IS - 1
M1 - 8378241
ER -