JP2807376B2 - Driving method of laser for excitation of optical fiber amplifier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The method of driving a laser diode according to the present invention is used for supplying a pumping laser to an optical fiber amplifier in the case of optical communication using, for example, an Elbeum-doped optical fiber amplifier. Things.

[0002]

2. Description of the Related Art Conventionally, when an excitation laser for exciting an optical fiber amplifier is obtained from a laser diode, one laser diode has conventionally been driven DC to emit light continuously.

[0003]

SUMMARY OF THE INVENTION
When the C drive is performed, the heat generated from the consumed power increases, and heat dissipation becomes difficult.

It is an object of the present invention to reduce the power consumption of a laser diode drive circuit.

[0005]

According to the driving method of the laser for exciting an optical fiber amplifier of the present invention, two or more laser diodes 1 shown in FIG. 1 are controlled by a pulse driving circuit 2, and each laser is driven as shown in FIG. The laser beams A and B for excitation are alternately emitted from the diode 1, and the laser beams A and B for excitation are shown in FIG.
And is supplied to the optical fiber amplifier 3.

[0006]

In the present invention, since the excitation laser beams A and B are alternately emitted from two or more laser diodes 1, the power of each of the emitted excitation laser beams A and B has a rated value (FIG. 2).
Of X) or more. In addition, in the present invention, since the excitation laser beams A and B having a power equal to or higher than the rated value are synthesized, the excitation laser power (Y in FIG. 2A) that continuously outputs one laser diode by DC driving is used. The excitation laser beam C having a large power can be supplied to the optical fiber amplifier 3 continuously.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail with reference to FIG. In FIG. 1, pulse currents E ₁ and E ₂ are alternately applied to two laser diodes 1 from a pulse driving circuit 2 as shown in FIG. The laser beams A and B for excitation are alternately emitted. In this case, the phase is finely adjusted for each laser diode to stabilize the output. Then, the two pumping laser beams A and B are combined by, for example, a polarization plane combining coupler 4 and supplied to the optical fiber amplifier 3 through the WDM coupler 5.

In the embodiment shown in FIG.
Although the number is used, the number of laser diodes 1 to be used may be more, for example, four.

Although the pumping lasers A and B emitted from the laser diode 1 are inputted from the front of the optical fiber amplifier 3 in the embodiment of FIG. 1, they may be inputted from the rear through the WDM coupler 6. . When four laser diodes 1 are used, they are divided into two sets of two, and the pumping laser from one set of laser diodes is input from the front of the optical fiber amplifier 3 and the other one.
The excitation laser from the pair of laser diodes may be input from the rear of the optical fiber amplifier 3.

[0010]

The driving method of the laser for exciting an optical fiber amplifier according to the present invention has the following effects. . The power consumption of the driving circuit for each laser diode can be reduced. . Although switching noise is applied to the pumping laser due to the pulse-driven switching operation, noise up to a high frequency is absorbed by the characteristic of storing light of the erbium-doped fiber, so that the amplified light is not affected. . Due to the pulse-driven switching operation, switching distortion is applied to the pumping laser. However, the distortion is canceled by combining the two pumping lasers, and does not affect the amplified light.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing one embodiment of a method for driving a laser for exciting an optical fiber amplifier according to the present invention.

FIG. 2A is an explanatory view showing an example of an excitation laser generated from one laser diode in the same driving method,
(B) is an explanatory diagram showing an example of an excitation laser generated from the other laser diode in the same driving method, and (c) is an explanatory diagram of an excitation laser obtained by combining the excitation lasers of (a) and (b).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laser diode 2 Pulse drive circuit 3 Optical fiber amplifier A, B Excitation laser

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ identification code FI H04B 10/17 (58) Fields investigated (Int.Cl. ⁶ , DB name) H01S 3/094 G02B 6/00 G02F 1/35 501 H01S 3/07 H01S 3/10 H04B 10/16 H04B 10/17 JICST file (JOIS)

Claims (1)

(57) [Claims] 1. A laser drive circuit for controlling two or more laser diodes to generate excitation laser light alternately from each of the laser diodes, synthesize the excitation laser light and send the laser light to an optical fiber amplifier. A method for driving a laser for exciting an optical fiber amplifier, comprising supplying the laser.