TY - JOUR
AU - Kiguchi, Masashi
AB - Abstract.We developed a system-on-chip (SoC)-incorporated light-emitting diode (LED) and avalanche photodiode (APD) modules to improve the usability and flexibility of a fiberless wearable functional near-infrared spectroscopy (fNIRS) system. The SoC has a microprocessing unit and programmable circuits. The time division method and the lock-in method were used for separately detecting signals from different positions and signals of different wavelengths, respectively. Each module autonomously works for this time-divided-lock-in measurement with a high sensitivity for haired regions. By supplying +3.3  V of power and base and data clocks, the LED module emits both 730- and 855-nm wavelengths of light, amplitudes of which are modulated in each lock-in frequency generated from the base clock, and the APD module provides the lock-in detected signals synchronizing with the data clock. The SoC provided many functions, including automatic-power-control of the LED, automatic judgment of detected power level, and automatic-gain-control of the programmable gain amplifier. The number and the arrangement of modules can be adaptively changed by connecting this exchangeable modules in a daisy chain and setting the parameters dependent on the probing position. Therefore, users can configure a variety of arrangements (single- or multidistance combinations) of them with this module-based system.
TI - Rearrangeable and exchangeable optical module with system-on-chip for wearable functional near-infrared spectroscopy system
JO - Neurophotonics
DO - 10.1117/1.NPh.5.1.011007
DA - 2018-01-01
UR - https://www.deepdyve.com/lp/spie/rearrangeable-and-exchangeable-optical-module-with-system-on-chip-for-JKuj1000u3
SP - 011007
EP - 011007
VL - 5
IS - 1
DP - DeepDyve
ER -