公开(公告)号：US5898502A

公开(公告)日：1999-04-27

申请号：US878543

申请日：1997-06-19

申请人： Yukio Horiuchi ,  Shu Yamamoto

发明人： Yukio Horiuchi ,  Shu Yamamoto

IPC分类号： G01J1/16 ,  G01J9/00 ,  H04B10/07 ,  H04B10/079 ,  H04B110/08 ,  G01J3/51

CPC分类号： G01J1/1626 ,  G01J9/00

摘要： In an optical wavelength monitoring apparatus for easily monitoring wavelength deviation, light introduced from a laser source 10 to an optical transmission line 12 is divided by directional couplers 14, 20. Optical output of the directional coupler 14 is converted into an electrical signal by a photodiode 16, and logarithmic-amplified by a logarithmic amplifier 18. Optical output of the directional coupler 20 is introduced to a photodiode 26 via an optical filter 24. The optical filter 24 is an optical element whose transmittance decreases as the incident light deviates from a specific wavelength .lambda.a. Optical output from the optical filter 24 is converted into an electrical signal by a photodiode 26, and logarithmic-amplified by a logarithmic amplifier 28. A differential amplifier 30 outputs a difference between outputs of the amplifiers 18, 28. A comparator 32 compares the output of the differential amplifier 30 with an alarm threshold Vref, and outputs an alarm-on signal when the difference is Vref or higher.

摘要翻译： 在用于容易监测波长偏差的光波长监测装置中，从激光源10引入到光传输线12的光被定向耦合器14,20分开。定向耦合器14的光输出由光电二极管转换成电信号 定向耦合器20的光输出通过滤光器24被引入光电二极管26.光学滤光器24是一种光学元件，其透光率随着入射光偏离特定的光学元件而降低 波长λa。 来自滤光器24的光输出由光电二极管26转换成电信号，由对数放大器28对数放大。差分放大器30输出放大器18,28的输出之间的差。比较器32将输出 差分放大器30具有报警阈值Vref，并且当差值为Vref或更高时输出报警开启信号。