摘要 |
A method and apparatus for measuring the optical attenuation of optical mediums characterized by a first transmitter and a second receiver being connected to one output of the optical medium and the second transmitter and first receiver being connected to the other output. Thus, four measuring processes can be obtained, which include measuring the signal from the first transmitter after it passes through the optical medium by the first receiver, measuring the signal from the first transmitter in the second receiver before it passes through the optical medium, measuring the signal from the second transmitter after it has passed through the optical medium by the second receiver and measuring the signal from the second transmitter by the first receiver before it passes through the optical medium. These four values are then processed to determine the exact attenuation of the optical medium.
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