| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical level checker capable of easily and stably checking an optical level at the end of an optical fiber, having a simple configuration, and inexpensive. <P>SOLUTION: The level checker is provided with a light-receiving element 20 for converting an optical signal into an electrical signal, a photoelectric amplifier 21 for amplifying the output of the light-receiving element, operational amplifiers 22, 23 for amplifying the output of the photoelectric amplifier with predetermined amplification factors respectively, comparators 24, 25, 26 provided in a plurality of stages and connected in parallel for comparing input voltages with a comparing reference voltage, light emitting devices 27, 28, 29 connected to the output side of each comparator, and a reference voltage source 32 for supplying the same comparing reference voltage to each comparator. The output signal of the photoelectric amplifier is directly input into a comparator, to display an upper limit of the signal level. Along with it, the output signal is input to comparators via predetermined operational amplifiers respectively, and an arbitrary level value and the lower limit of the signal level are displayed. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
