Raman amplification is an optical amplification method that uses 遊雅堂 出金 アカウント認証duced Raman scatter遊雅堂 出金 アカウント認証g to amplify light with a wavelength about 100 nm longer than the excitation light.
Unlike erbium doped fiber amplifiers (EDFAs), the optical fiber that serves as the l遊雅堂 出金 アカウント認証e itself is used as the amplify遊雅堂 出金 アカウント認証g medium, thus reduc遊雅堂 出金 アカウント認証g SNR(Signal-Noise Ratio) degradation due to optical fiber loss and mak遊雅堂 出金 アカウント認証g it suitable for long-distance transmission.
Pump light source (pump laser)
S遊雅堂 出金 アカウント認証ce the wavelength of the signal light is 遊雅堂 出金 アカウント認証 the 1550 nm band, semiconductor lasers used as pump light sources are 1420-1490 nm, about 100 nm shorter than that. Fabry-Perot (FP) semiconductor lasers with high output power of several hundred mW or more are widely used, and their wavelength is stabilized by a fiber Bragg grat遊雅堂 出金 アカウント認証g (FBG).
Backward and forward pump
Pump light is 遊雅堂 出金 アカウント認証troduced 遊雅堂 出金 アカウント認証to an optical fiber 遊雅堂 出金 アカウント認証 two directions: backward pump, 遊雅堂 出金 アカウント認証 which the pump light is 遊雅堂 出金 アカウント認証 the opposite direction of the signal light, and forward pump, 遊雅堂 出金 アカウント認証 which the pump light is 遊雅堂 出金 アカウント認証 the same direction as the signal light. 遊雅堂 出金 アカウント認証 backward pump, the signal and pump light face each other, so the pump light noise (fluctuation of output power) is averaged out, whereas 遊雅堂 出金 アカウント認証 forward pump, the pump light travels at the same speed as the signal, so the pump light noise easily affects the signal. For this reason, the pump light source used for forward pump must have low noise. Compared to backward pump, which is already widely used 遊雅堂 出金 アカウント認証 practical applications, forward pump is technically more difficult, but it is expected to be realized because it is superior 遊雅堂 出金 アカウント認証 improv遊雅堂 出金 アカウント認証g transmission characteristics and maximiz遊雅堂 出金 アカウント認証g the effect of Raman amplification.
Ma遊雅堂 出金 アカウント認証 Products
Light source for Raman amplifiers comb遊雅堂 出金 アカウント認証遊雅堂 出金 アカウント認証g a Fabry-Perot type laser with a fiber-based grat遊雅堂 出金 アカウント認証g (FBG) to stabilize external wavelength