# US 2013/0156422 A1 · Optical communication device, wavelength number measurement device, optical repeater, and wavelength number measurement method

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2013/0156422 A1
- Document ID: US20130156422A1
- Status: Published application
- Kind: A1
- Application number: 13/711,773
- Filed: 2012-12-12
- Published: 2013-06-20
- Earliest claimed: 2011-12-19
- Assignees: Fujitsu Limited
- Inventors: Taizo MAEDA; Takashi Toyomaki; Takuya Miyashita
- Web page: https://patentgrep.com/patent/US20130156422A1

## CPC

- H04B 10/07957: {Monitoring or measuring wavelength}
- H04B: TRANSMISSION

## Abstract

In an optical communication device, a light source is capable of varying the wavelength of light to be output. An optical multiplexer multiplexes light output from the light source with signal light received from a transmission path. To an optical medium, light output from the optical multiplexer is input. A monitor monitors light having a predetermined wavelength output from the optical medium. A wavelength number measuring unit measures the number of wavelengths of signal light transmitted through the transmission path based on the result of monitoring by the monitor.

## Claims

### Claim 1

An optical communication device comprising:
a light source capable of varying the wavelength of light to be output;
a wavelength controller configured to control the wavelength of the light source;
an optical multiplexer configured to multiplex light output from the light source with signal light received from a transmission path;
an optical medium to which light output from the optical multiplexer is input;
a monitor configured to monitor light having a predetermined wavelength output from the optical medium; and
a wavelength number measuring unit configured to measure the number of wavelengths of signal light transmitted through the transmission path based on the result of monitoring by the monitor.

### Claim 2 (depends on 1)

The optical communication device according to claim 1, wherein
the wavelength number measuring unit measures the number of wavelengths of the signal light based on the presence/absence of the light having the predetermined wavelength.

### Claim 3 (depends on 1)

The optical communication device according to claim 1, wherein
the wavelength number measuring unit measures the wavelength of the signal light based on the presence/absence of the light having the predetermined wavelength.

### Claim 4 (depends on 3)

The optical communication device according to claim 3, wherein
the wavelength number measuring unit measures the wavelength of the signal light based on the presence/absence of the light having the predetermined wavelength and the wavelength of wavelength variable light output from the light source.

### Claim 5 (depends on 1)

The optical communication device according to claim 1, further comprising an automatic level controller configured to correct spontaneous emission light at the time of automatic level control of the signal light based on the number of wavelengths measured by the wavelength number measuring unit.

### Claim 6

A wavelength number measuring device comprising:
a light source capable of varying the wavelength of light to be output;
an optical multiplexer configured to multiplex light output from the light source with signal light received from a transmission path;
an optical medium to which light output from the optical multiplexer is input;
a monitor configured to monitor light having a predetermined wavelength output from the optical medium; and
a wavelength number measuring unit configured to measure the number of wavelengths of signal light transmitted through the transmission path based on the result of monitoring by the monitor.

### Claim 7

An optical repeater comprising:
a light source capable of varying the wavelength of light to be output;
a wavelength controller configured to control the wavelength of the light source;
an optical multiplexer configured to multiplex light output from the light source with signal light received from a transmission path;
an optical medium to which light output from the optical multiplexer is input;
a monitor configured to monitor light having a predetermined wavelength output from the optical medium; and
a wavelength number measuring unit configured to measure the number of wavelengths of signal light transmitted through the transmission path based on the result of monitoring by the monitor.

### Claim 8

A wavelength number measurement method comprising:
multiplexing light output from a light source with signal light received from a transmission path;
causing the multiplexed light to enter an optical medium;
monitoring light having a predetermined wavelength output from the optical medium; and
measuring the number of wavelengths of signal light transmitted through the transmission path based on the result of monitoring.