Shigeru Obo

TL;DR: In this paper, the phase adjustment circuit was digitized to digitize a phase adjusting circuit, which adjusts the phase of a reference signal in such a way that the sensitivity of a lock-in detection becomes largest out of a signal processing circuit used for the lockin detection.

TL;DR: In this article, a reverse flow map (flow rate map of the reverse side) for converting a signal from a heating resistor into the air flow rate is corrected, and then the corrected reverse flow rate upon the occurrence of reverse flowing is corrected in two steps by utilizing the corrected flow map.

TL;DR: In this article, the authors proposed a method to realize a low insertion loss, a low distributing dispersion and a low cost with respect to an optical star coupler for a single mode optical fiber, as well as providing a twisted/welded part on both sides of a tapered twisted/wedged/drawn part of the center part of plural bundled optical glass fibers.

TL;DR: In this article, the modulation of luminous intensity of a cycle T shorter than time width τ characteristic to the time change of a phenomenon to be measured is applied to a light emitting part 1 and the passing light of an optical fiber is detected and an optical signal receiving modulation is photoelectrically converted by a light detection part 3 and the converted signal is subjected to AC amplification by combining a noise filter part 30 and an amplifying part 40 to be demodulated by a demodulation part 20.

TL;DR: In this paper, the authors propose to self-diagnose from a detected value whether a fault exists or not, by detecting an AC component related to a driving frequency of an optical modulator, in the output of the optical system.