... optical time domain reflectometry (OTDR) is the latest FTTx optical fiber cable-based test instrument. It has light weight, elegant appearance, ... very simple. User only needs to connect in the optical fiber, click [Test] button, then the instrument will automatically ... framesRange of refractive index1.00000~2.00000Range of optical-cable correction factor0.80000~1.0000DisplayColor TFT LCD, 5.1 ...