| 摘要 |
PROBLEM TO BE SOLVED: To provide a photodetector and a light amplifier that achieve miniaturization and cost reduction. SOLUTION: The photodetector 14 has a housing 21 and, in the upper part of the housing 21, an aperture 24 is provided for letting through a light (monitoring light) emitted from a monitoring optical fiber 13. A photodetecting element 26 for detecting the monitoring light is arranged in the housing 21. On the upper inner surface of the housing 21, an optical filter 28 for extracting a specified wavelength band of light is installed, blocking the aperture 24 and also sealing airtight the inside of the housing 21. As the optical filter 28, a blocking filter blocking an excited light but not a signal light or a wavelength-selective filter transmitting only the light in the signal light wavelength band is used. The light filter for extracting a specified wavelength band of light attached to the housing for blocking the aperture in the housing achieves apparatus miniaturization and cost reduction. COPYRIGHT: (C)2004,JPO |
