KR20000051570A - Apparatus for generating variable wavelenth optical source having a function of optical amplification - Google Patents

Abstract

PURPOSE: An apparatus for generating a light source of a variable wave having an optical amplification function is provided to randomly select and output a light beam having a necessary light wave property by feeding back outputting light beams partially and passing through a filter for tuning the feedback light beams. CONSTITUTION: A switching part(51) interrupts to selectively output light beams applied from a tunable filter(57). A light beam is outputted from the switching part to an input of an isolator(52) and applied to a wavelength division multiplexer(54). The multiplexer simultaneously outputs the light beams applied from the isolator and light beams applied from a laser diode(53) to a single light path, and is supplied with pumping light beams from the laser diode. An optical amplification fiber(55) is applied with the light beams input via the multiplexer and synthesized with the pumping light beams to output the synthesized light beams to a tap coupler(56) after amplification. The tap coupler separates the input light beams into an output light signal and a feedback light signal in a ratio of 99:1 for outputting light beams corresponding to 99 as a light source and the remaining light beam to a tunable filter(57) for filtering the input light beam.

Description

Apparatus for generating variable wavelenth optical source having a function of optical amplification

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to optical communication, and more particularly, to a variable wavelength light source generation device having an optical amplification function capable of amplifying and outputting input light and generating a light source with high output by selecting a desired wavelength.

Optical communication technology using optical fiber is mainly used for information communication between countries through submarine cable because it can transmit large amount of information at high speed and there is no signal interference or crosstalk caused by electromagnetic induction.

Recently, optical communication has been used as a backbone communication network for high-speed broadband multimedia communication including voice and data communication during the switching period and CATV (Cable TV) and VOD (Video On Demand) as the multiplexing technology and the network technology have advanced. It is gradually expanding.

On the other hand, the optical communication modulates light having different wavelengths generated from a plurality of laser diodes, and multiplexes a multi-wavelength optical signal using a multiplexer and transmits them to a destination through a predetermined optical path. In the corresponding destination, the multiplexed optical signal is demultiplexed and separated into a plurality of optical signals having original wavelengths.

Therefore, the optical elements used in the optical communication system have predetermined characteristics for all laser light sources used in the optical communication system. When A and B are the same optical element, the characteristics of all the laser light sources are different from each other. Should be the same.

Therefore, in the manufacturing process of the optical device to check the output characteristics of the optical device manufactured in the final step, in order to examine the output characteristics of all the laser light source of the optical device there must be a laser light source for all bands.

However, the above-described conventional optical communication technology requires a plurality of laser diodes corresponding to each wavelength in order to construct a multi-wavelength light source. Since this laser diode cannot be manufactured by selecting a specific wavelength in its manufacturing process, many laser diodes are required. After fabricating a positive laser diode first, a multi-wavelength light source should be constructed using a laser diode that generates a desired wavelength.

Therefore, since a plurality of the expensive laser diodes are configured to check the performance of each optical device, there is a problem that the manufacturing cost is increased accordingly.

In addition, in order to inspect the output characteristics of the optical device, the light source applied to the input terminal of the optical device requires a high output. Since the laser diode has a low output gain, an optical amplifier is provided at the output terminal to the input of the optical device. Will be authorized.

That is, there is a problem that a separate light source generation device and an amplifier must be provided for the performance inspection of the optical device.

Accordingly, the present invention has been made in view of the above circumstances, and is configured so that a part of the output light is fed back through a tunable filter so that the light having the necessary optical wavelength characteristics can be arbitrarily selected and outputted. It is an object of the present invention to provide a variable wavelength light source generating device having an amplification function.

In addition, an object of the present invention is to provide a variable wavelength light source generation apparatus having an optical amplification function capable of generating and outputting a high power light source by amplifying and outputting light of a selected wavelength by being fed back.

1 is a view showing the internal configuration of a variable wavelength light source generation device having an optical amplification function according to the present invention.

Figure 2 shows the amplification characteristics of a typical optical amplified optical fiber.

3 is a view illustrating a 1551 nm wavelength light source generation test result in a general light source generation apparatus.

FIG. 4 is a diagram illustrating a test result of generating a 1551 nm wavelength light source in the apparatus shown in FIG. 1; FIG.

*** Explanation of symbols for the main parts of the drawing ***

51: switching unit, 52: isolator,

53: laser diode, 54: wavelength division multiplexer (WDM),

55: optically amplified optical fiber, 56: tab coupler,

57: tunable filter.

The variable wavelength light source raw growth value having an optical amplification function according to the present invention for realizing the above object comprises: switching means for selectively intermitting feedback light applied from an input light and a tunable filter, and light applied from the switching means; A wavelength division multiplexer that receives pumped light and outputs the optical amplification fiber through one transmission path, an optical amplification fiber that amplifies and outputs the light applied from the wavelength division multiplexer, and an amplified light applied from the optical amplification fiber And a tunable filter for outputting a specific wavelength band of light applied from the optical separation means by dividing a by a predetermined ratio, a part of which is output as output light, a part of which is applied to the tunable filter. It is done.

That is, as described above, the optical amplification function is performed, and a specific wavelength is selectively amplified and output using the pumping light, thereby generating a high power light source.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a block diagram showing an internal configuration of an apparatus according to the present invention.

In the figure, reference numeral 51 denotes a switching unit for intermittently outputting the input light and light applied from the tunable filter 57 to be described later, which is an input light when the apparatus is used as a general optical amplifier. Is switched to output to the next stage, and when the apparatus is used as a variable wavelength light source generating device, it is switched to output the feedback light applied from the tunable filter 57 to the next stage.

On the other hand, the output light from the switching unit 51 is applied to the input of the isolator 52, in which the output light applied from the switching unit 51 is a wavelength division multiplexer (Wavelength Division Multiplexer) : WDM) (54).

In addition, the wavelength division multiplexer 54 performs the function of simultaneously outputting the light applied from the isolator 52 and the light applied from the laser diode 53 into one light path.

Here, the pumping light applied to the wavelength division multiplexer 54 is supplied from a laser diode 53 which generates light of, for example, a wavelength of 980 nm.

On the other hand, the input light and the pumping light is synthesized through the wavelength division multiplexer 54 is applied to the input of the optical amplification fiber 55, the optical amplification fiber 55 is Erbium, prasedium, or It is manufactured by doping rare-earth ions such as neodium, and is excited by pumping light to amplify and output the input light.

In addition, the light amplified through the optical amplification optical fiber 55 is applied to the input of the tab coupler 56, the tap coupler 56 receives the input light in a predetermined ratio, for example, the output light signal and the feedback light The signal is separated and output at a ratio of 99: 1. That is, light corresponding to 99 is output as a light source, and light corresponding to 1 is applied to the input of the tunable filter 57.

On the other hand, the tunable filter 57 is a device that can selectively filter the light of a specific wavelength from the input light, which filters the light of a specific wavelength of the light applied from the tap coupler 56 by the switching unit 51 Will be applied as input.

That is, in the above configuration, a predetermined ratio of light is fed back to the tunable filter 57, and the output end of the tunable filter 7 is coupled with the input end of the switching unit 51 to form a ring structure. Will be formed.

Next, the operation of the apparatus shown in FIG. 1 will be described.

The device having the above configuration can be selectively used as an optical amplifier and a variable wavelength generation device. When the device is used as an optical amplifier, the switching unit 51 outputs input light to the isolator 52. When the device is used as a variable wavelength generation device, the switching unit 51 is configured to output the feedback light applied from the tunable filter 57 to the isolator 52.

First, when the device is used as an optical amplifier, the switching unit 51 outputs the input light from the outside to the isolator 52, and the output light of the isolator 52 is applied to the wavelength division multiplexer 54. Will be.

The wavelength division multiplexer 54 receives the light applied from the isolator 52 and the pumping light applied from the laser diode 53 to be multiplexed through one optical transmission path to transmit the optical amplification fiber 55. do.

Subsequently, in the optical amplification fiber 55, the rare earth ions doped by the received pumping light are activated to amplify the light input through the isolator 52. Here, the amplification characteristic in the optical amplification optical fiber 55 is as shown in FIG.

On the other hand, the light amplified through the optical amplification optical fiber 55 is applied to the tap coupler 56, the tap coupler 56 is divided into a predetermined ratio, for example, 99: 99 corresponds to 99 Light is output as output light, and light corresponding to 1 is applied to the tunable filter 57.

That is, when used as an optical amplifier to set the light output through the switching unit as the input light.

On the other hand, when the device is used as a variable wavelength light source generation device, the switching unit 51 is set to output the feedback light applied from the tunable filter 57 to the isolator 52.

First, the pumping light applied through the laser diode 53 is applied to the optical amplification fiber 55 through the wavelength division multiplexer 54, and the optical amplification fiber 55 amplifies and outputs the input pumping light. Bar, the output characteristic is as shown in FIG.

On the other hand, the light amplified and output through the optical amplification fiber 55 is applied to the input of the tab coupler 56, the tap coupler 56 is divided into a predetermined ratio, for example, a ratio of 99: 1 Light corresponding to 99 is output to the output terminal, and light corresponding to 1 is applied to the tunable filter 57.

Here, the output terminal of the tunable filter 57 is coupled to the input terminal of the switching unit 51, so that the light applied from the tap coupler 56 to the tunable filter 57 becomes the feedback light.

Meanwhile, the light applied to the tunable filter 57 filters the light of a specific wavelength band and is applied to the switching unit 51. The tunable filter 57 has its wavelength band set by the user. That is, the user can select light of a desired wavelength.

In addition, the light output from the tunable filter 57 is applied to the input of the switching unit 51 to repeat the above-described operation, whereby the light of the wavelength selected by the user is amplified and output.

3 is an experimental result of the conventional light source generating apparatus, and FIG. 4 is a diagram showing an experimental result of the apparatus according to the present invention operating as described above.

That is, FIG. 3 generates a light source using a laser diode having a characteristic of outputting light having a wavelength of 1551 nm, which has a gain of about -2 dBm at a wavelength of 1551 nm.

On the other hand, Figure 4 shows the light source output characteristics when the wavelength band of the light source generating apparatus according to the present invention is set to 1551nm, as shown in Figure 4, has a signal strength of about 11dBm in the 1551nm wavelength band.

That is, a part of the output light of the optical amplified optical fiber to amplify and output the pumped light, and provided with a tunable filter for selectively filtering a specific wavelength band of the returned light, the light output through the tunable filter optically amplified optical fiber By forming the ring-shaped structure to be applied to, it is possible to stably generate a high power light source for the desired wavelength band.

Therefore, according to the apparatus of the present invention, it is possible to generate a high power light source by performing an optical amplification function and selectively amplifying and outputting a specific wavelength using the pumping light.

On the other hand, the present invention is not limited to the above embodiments and can be modified in various ways without departing from the technical spirit of the present invention.

As described above, according to the present invention, it is possible to generate a high power light source by performing an optical amplification function and selectively amplifying and outputting a specific wavelength using the pumping light.

Claims (2)

Switching means for selectively intermitting the feedback light applied from the input light and the tunable filter; A wavelength division multiplexer which receives light applied from the switching means and pumped light and outputs the optical amplified optical fiber through one transmission path; An optical amplified optical fiber for amplifying and outputting light applied from the wavelength division multiplexer; Optical separation means for dividing the amplified light applied from the optical amplified optical fiber into a predetermined ratio, partly outputting the output light, and partly applying the tunable filter; And a tunable filter for outputting a specific wavelength band of the light applied from the optical separation means. The method of claim 1, The switching means outputs the input light from the outside to the wavelength division multiplexer when used as an optical amplifier, and outputs the feedback light applied from the tunable filter to the wavelength division multiplexer when used as a light source generator. Variable wavelength light source generating device having an optical amplification function, characterized in that.