| 摘要 |
PROBLEM TO BE SOLVED: To provide a closed system signal propagation device including an optical signal propagation route and an electric signal propagation route, in which attenuation in a signal strength is small and a stable optical signal is obtained, and an absorption spectrometry device and an optical memory device including it.SOLUTION: In an absorption spectrometry device 8, a closed system signal propagation device 40, which repeatedly propagates a signal, via a circulating closed route is constituted by a first optical fiber (optical signal propagation route) 28, and an electric signal propagation route between a photodetector 34 and a laser diode 30. Since there is no need for using an optical amplifier, oscillation or a signal waveform caused by the oscillation is not deformed, so that an output signal can be taken out sufficiently, and besides, conformity between an amplification band of an optical amplifier and a frequency of a laser beam becomes unnecessary, so that an output signal can be obtained easily. In addition, compared with a case in which the closed system signal propagation device is constituted solely by an optical fiber (optical signal propagation route), the number of components are reduced, and the device is made small in size and inexpensive. |
