Because of the massive growth of the optical communications networks during the past years, a need for accurate measurements of fiber optic power has risen. Our fiber optic power meters are based on InGaAs photodiodes. We have two types of detectors; one type utilizes a simple plain photodiode, attached to an aluminum frame, while the other type consists of an integrating sphere with a photodiode attached to it. We have extended the power range of our fiber optic measurements to 1 nW - 200 mW at the 1550 nm wavelength window and 1 nW - 7 mW at the 1310 nm wavelength window.
J. Envall, P. Kärhä and E. Ikonen
”Measurements of fibre optic power using photodiodes with and without an integrating sphere”
Metrologia, 41, 353-358 (2004)
S-108.2110 Optiikka
S-108.3110 Optical Communications
Tuoma Hieta
tuomas.hieta(at)tkk.fi
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Figure 1. Closeup of an InGaAs photodiode. The diameter of the active area (the reflective circle at the center) is 5 mm. |
Figure 2. Two detectors with plain photodiodes. On the left: detector with fiber adapter removed. On the right: detector with fiber adapter attached and fiber connected. |
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Figure 3. Integrating sphere detector. |
Figure 4. Fiber coupled laser source at 1310 nm wavelength. |
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Figure 5. Erbium doped fiber amplifier (EDFA) is used to amplify the laser power at 1550 nm wavelength window. Powers as high as 1 W can be reached. |