JP2002257632A - Optical wavelength measuring instrument and its method, program and recording medium with the program recorded thereon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical wavelength measuring instrument that can specify the wavelength of a laser light even if the wavelength of the laser light is much swept. SOLUTION: The measuring instrument to measure the wavelength of a variable wavelength light of a variable wavelength light source 12 is provided with a reference optical device 40 where the relation between a group delay time and the wavelength of the wavelength tunable light is known, a measuring portion 32 to measure the group delay time of the reference optical device 40, a recording portion 34 of characteristic the reference optical device to record a correspondence of the group delay time of the reference optical device 40 to the wavelength of the wavelength tunable light transmitted the reference optical device 40, and a wavelength measuring portion 36 to measure the wavelength of the wavelength tunable light based on recorded contents in the recording portion 34 of the characteristics of the reference optical device 40 and the group delay time of the reference optical device 40, wherein the wavelength of the laser light can be specified even if the wavelength of the laser light is much swept, because the group delay time can be measured even if the wavelength of the laser light is much swept.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a wavelength measurement of a light source for generating a laser beam or the like.

[0002]

2. Description of the Related Art A conventional system for measuring the chromatic dispersion of an optical device is disclosed, for example, in Japanese Patent Publication No. 7-9386, and its configuration is shown in FIG. According to the chromatic dispersion measurement system shown in FIG.
2 generates a measuring laser beam, and the laser beam is
Are intensity-modulated by an external modulator 108 based on the electric signal generated by the optical modulator 104 and are incident on an optical fiber 104 as an optical device. The measurement laser light transmitted through the optical fiber 104 is photoelectrically converted by the optical receiver 105. Optical receiver 1
The phase difference between the electric signal photoelectrically converted in step 05 and the electric signal generated by the oscillator 101 is measured by the phase comparator 106. From the phase difference, the group delay time and chromatic dispersion of the optical fiber 104 can be obtained.

In performing the above-described measurement, it is necessary to sweep the wavelength of the measurement laser beam generated by the measurement laser 102 and to accurately measure the wavelength of the measurement laser beam. The method for that is as follows. First,
The first wavelength of the measuring laser light is measured by the optical wavelength meter 112 in advance. Then, the wavelength of the monitoring laser light generated by the monitoring laser 110 is adjusted to the first wavelength of the measuring laser light. Then, the wavelength of the measuring laser light is swept.
Here, the laser beam for measurement and the laser beam for monitoring are combined by the optical synthesizer 113 to obtain a beat signal based on the frequency difference between the laser beam for measurement and the laser beam for monitoring. The beat signal is photoelectrically converted by the optical receiver 105c to obtain an intermediate frequency signal, which is observed by the spectrum analyzer 111. Since the beat signal is observed by the spectrum analyzer 111, the difference in frequency between the measuring laser light and the monitoring laser light can be measured. Therefore, a change in the wavelength of the measurement laser light can be measured.

[0004]

However, when the measurement laser light is swept in a narrow wavelength range (for example, 1.0 nm or less), the wavelength range that can be swept at one time is limited by the measurable band of the spectrum analyzer 111. . Each time the wavelength of the measurement laser is swept, the monitoring laser 1
It is necessary to match the wavelength of the monitoring laser light generated by 10 with the first wavelength of the measuring laser light, which takes time and labor. In addition, the wavelength range of the laser light generated by the monitoring laser 110 must be substantially the same as the wavelength range of the measurement laser light, which makes the monitoring laser 110 expensive.

The above problem occurs because there is no laser beam wavelength measuring device capable of specifying the wavelength of the measuring laser beam even when the wavelength of the measuring laser beam is swept largely.

Accordingly, an object of the present invention is to provide an optical wavelength measuring device or the like which can specify the wavelength of a laser beam even when the wavelength of the laser beam is swept largely.

[0007]

According to the present invention, there is provided an optical wavelength measuring apparatus for measuring the wavelength of a variable wavelength light generated by a variable wavelength light source, wherein the variable wavelength light is transmitted and the transmitted variable wavelength light is transmitted. The reference light device having a known relationship between the physical quantity of the wavelength light and the wavelength is provided, and reference light measuring means for measuring the physical quantity of the variable wavelength light transmitted through the reference light device.

According to the optical wavelength measuring apparatus configured as described above, the physical quantity of the variable wavelength light transmitted through the reference light device is measured by the reference light measuring means, and the physical quantity and the wavelength of the variable wavelength light are known. Because of this, the wavelength of the variable wavelength light can be measured. By appropriately selecting this physical quantity, the wavelength can be measured even when the wavelength of the variable wavelength light is swept largely.

According to a second aspect of the present invention, there is provided the first aspect of the present invention, wherein a modulation signal generating means for generating a modulation signal for providing a modulation frequency to be used for intensity modulation; Light modulation means for supplying intensity-modulated variable wavelength light to the reference light device, and the reference light measurement means measures the phase difference between the variable wavelength light transmitted through the reference light device and the modulation signal. is there.

The invention according to claim 3 is the invention according to claim 2, wherein the group delay time measuring means for measuring the group delay time of the reference optical device based on the phase difference, and the group delay of the reference optical device Reference light device characteristic recording means for recording the correspondence between the time and the wavelength of the variable wavelength light transmitted through the reference light device, and the variable wavelength light based on the recorded contents of the reference light device characteristic recording means and the group delay time of the reference light device. Wavelength measuring means for determining a wavelength.

According to a fourth aspect of the present invention, in the second aspect of the present invention, the optical modulation means also supplies a variable wavelength light intensity-modulated at the modulation frequency to the device to be measured, and controls the device to be measured. It is configured to include a DUT measuring unit that measures a phase difference between the transmitted variable wavelength light and the modulation signal.

A fifth aspect of the present invention is the invention of the second aspect, wherein the group delay time measuring means for measuring the group delay time of the reference optical device based on the phase difference, and a target variable wavelength light source A target group delay time calculating means for calculating a target group delay time of the reference optical device based on a target wavelength of the variable wavelength light, and a delay time comparing means for comparing the group delay time with the target group delay time. Be composed.

The invention according to claim 6 is the invention according to claim 3, wherein the target wavelength of the variable wavelength light of the target variable wavelength light source and the wavelength of the variable wavelength light obtained by the wavelength measuring means are determined. Wavelength comparing means for comparing.

The invention according to claim 7 is the invention according to claim 3, wherein the wavelength of the variable wavelength light generated by the variable wavelength light source is controlled based on the wavelength of the variable wavelength light obtained by the wavelength measuring means. It is configured to include a wavelength control unit and an optical demultiplexing unit that extracts the variable wavelength light generated by the variable wavelength light source from between the variable wavelength light source and the light modulation unit.

The invention according to claim 8 is the invention according to any one of claims 2 to 7, wherein the reference optical device is a dispersion compensating fiber, a dispersion compensating fiber Bragg grating and a single mode optical fiber. Is one of the

The ninth aspect of the present invention is the invention of the first aspect, wherein the reference light measuring means measures the amplitude of the variable wavelength light transmitted through the reference light device.

A tenth aspect of the present invention is the invention of the ninth aspect, wherein the reference light device characteristic recording means for recording correspondence between the amplitude and the wavelength of the variable wavelength light transmitted through the reference light device; Wavelength measuring means for obtaining the wavelength of the variable wavelength light from the recorded content of the reference light device characteristic recording means and the amplitude of the variable wavelength light.

An eleventh aspect of the present invention is the invention according to the ninth aspect, wherein a modulation signal generating means for generating a modulation signal for providing a modulation frequency to be used for intensity modulation; The device is configured to include an optical modulation unit that supplies the variable-wavelength light whose intensity has been modulated to the device to be measured, and a DUT measurement unit that measures the phase difference between the variable-wavelength light transmitted through the device to be measured and the modulation signal.

According to a twelfth aspect of the present invention, in accordance with the ninth aspect of the present invention, the target amplitude of the variable wavelength light transmitted through the reference light device based on the target wavelength of the variable wavelength light of the target variable wavelength light source. , And amplitude comparing means for comparing the amplitude with the target amplitude.

The invention according to claim 13 is the invention according to claim 10, wherein the target wavelength of the variable wavelength light of the target variable wavelength light source and the wavelength of the variable wavelength light obtained by the wavelength measuring means are determined. Wavelength comparing means for comparing.

According to a fourteenth aspect of the present invention, there is provided the wavelength control apparatus for controlling the wavelength of the variable wavelength light of the variable wavelength light source based on the wavelength of the variable wavelength light obtained by the wavelength measuring means. Means for extracting variable wavelength light from the variable wavelength light source from between the variable wavelength light source and the light modulation means.

A fifteenth aspect of the present invention is the invention according to any one of the ninth to fourteenth aspects, wherein the reference light device comprises: ¹² C ₂ H ₂ , ¹³ C ₂ H ₂ , H ¹³ C ¹⁴ N, which is any one of argon, xenon and krypton.

According to a sixteenth aspect of the present invention, there is provided an optical wavelength measuring apparatus for measuring the wavelength of the variable wavelength light generated by the variable wavelength light source, wherein the variable wavelength light is transmitted, and the physical quantity and the wavelength of the transmitted variable wavelength light. A reference light device having a known relationship with
Reference light measuring means for measuring the physical quantity of the variable wavelength light transmitted through the reference light device; reference light device characteristic recording means for recording the correspondence between the physical quantity and the wavelength of the variable wavelength light transmitted through the reference light device; Wavelength measuring means for obtaining the wavelength of the variable wavelength light from the recorded contents of the device characteristic recording means and the measured physical quantity.

According to a seventeenth aspect of the present invention, there is provided a variable wavelength light source for generating a variable wavelength light, a reference light device through which the variable wavelength light is transmitted, and a relation between the physical quantity and the wavelength of the transmitted variable wavelength light is known. A reference light measuring means for measuring a physical quantity of the variable wavelength light transmitted through the reference light device; and a light wavelength measuring method for measuring the wavelength of the variable wavelength light of the optical wavelength measuring device, comprising: A reference light device characteristic recording step of recording the correspondence with the wavelength of the variable wavelength light transmitted through, and a wavelength measurement step of obtaining the wavelength of the variable wavelength light from the recorded contents of the reference light device characteristic recording means and the measured physical quantity. This is an optical wavelength measurement method provided.

According to the present invention, there is provided a variable wavelength light source for generating a variable wavelength light, a reference light device through which the variable wavelength light is transmitted, and a relation between the physical quantity and the wavelength of the transmitted variable wavelength light is known. A reference light measuring means for measuring a physical quantity of the variable wavelength light transmitted through the reference light device, and a program for causing a computer to execute a light wavelength measurement process for measuring the wavelength of the variable wavelength light of the optical wavelength measurement device having the reference light recording device. A recording medium readable by a computer, comprising: a reference light device characteristic recording process for recording a correspondence between a physical quantity and a wavelength of the variable wavelength light transmitted through the reference light device; A computer that stores a program for causing a computer to execute a wavelength measurement process for obtaining the wavelength of the variable wavelength light from the measured physical quantity. Thus a recording medium which is readable.

According to a nineteenth aspect of the present invention, there is provided a variable wavelength light source for generating a variable wavelength light, a reference light device through which the variable wavelength light is transmitted, and a relation between the physical quantity and the wavelength of the transmitted variable wavelength light is known. A reference light measuring means for measuring the physical quantity of the variable wavelength light transmitted through the reference light device; and a program for causing a computer to execute an optical wavelength measurement process for measuring the wavelength of the variable wavelength light of the optical wavelength measurement device. hand,
A reference light device characteristic recording process for recording the correspondence between the physical quantity and the wavelength of the variable wavelength light transmitted through the reference light device, and the wavelength of the variable wavelength light is obtained from the recorded contents of the reference light device characteristic recording means and the measured physical quantity. Wavelength measurement processing,
Is a program for causing a computer to execute.

[0027]

Embodiments of the present invention will be described below with reference to the drawings.

First Embodiment FIG. 1 is a block diagram showing a configuration of an optical wavelength measuring device according to a first embodiment of the present invention. The optical wavelength measuring apparatus according to the embodiment of the present invention includes a variable wavelength light source 12, a modulation power source 14, an optical modulator 16, a photoelectric converter 22, and a phase comparator 2.
4, a group delay time measuring unit 32, a reference light device characteristic recording unit 34, a wavelength measuring unit 36, and a reference light device 40.
The optical wavelength measuring device according to the embodiment of the present invention is for measuring the optical wavelength of the variable wavelength light source 12.

The variable wavelength light source 12 generates a variable wavelength light whose wavelength can be changed. By the variable wavelength light source 12,
The wavelength of the variable wavelength light can be swept. The modulation power supply 14 supplies the optical modulator 16 with a modulation signal having a frequency (modulation frequency) at which the variable wavelength light is to be modulated. Optical modulator 1
6 modulates the intensity of the variable wavelength light at the modulation frequency and enters the reference light device 40. The light modulator 16 generally has lithium niobate (LN), but may not include LN as long as the light intensity can be modulated.

The reference light device 40 transmits the light output from the light modulator 16. The correspondence between the wavelength of light and the group delay time of the reference light device 40 is known. FIG. 2 shows an example of the correspondence between the wavelength of light incident on the reference light device 40 and the group delay time. As shown in FIG. 2, as the wavelength increases, the group delay time monotonically decreases. Therefore,
The wavelength and the group delay time have a one-to-one correspondence. Also, the group delay time is continuous for the wavelength sweep. On the other hand, the absolute value of the group delay time cannot be measured, and only the difference, that is, the relative value can be measured. Therefore, if the difference ΔGD between the group delay time of the reference light device 40 at the start of the wavelength measurement of the variable wavelength light and the group delay time of the reference light device 40 at a certain measurement is measured, the difference ΔGD at the start of the wavelength measurement of the variable wavelength light The difference Δλ between the wavelength of the variable wavelength light and the wavelength of the variable wavelength light at the time of a certain measurement can be obtained.

The reference optical device 40 is, for example, a dispersion compensating fiber (DCF), a dispersion compensating fiber Bragg grating (FBG), or a long single mode optical fiber. Further, the reference light device 40 has a dispersion value [p
[s / nm] is better.

The photoelectric converter 22 converts the light transmitted through the reference light device 40 into an electric signal. The phase comparator 24
The electric signal output from the photoelectric converter 22 and the power supply for modulation 14
And measure the phase difference with the modulation signal output from. The group delay time measuring unit 32 measures the group delay time of the reference light device 40 based on the phase difference measured by the phase comparator 24 and the frequency of the modulation signal. Reference light device characteristic recording unit 34
Records the correspondence between the wavelength of the variable wavelength light transmitted through the reference light device 40 and the group delay time of the reference light device 40. Note that the correspondence is as shown in FIG. 2 and is known. The wavelength measuring unit 36 measures the wavelength of the variable wavelength light from the recorded contents of the reference light device characteristic recording unit 34 and the group delay time of the reference light device 40.

Next, the operation of the optical wavelength measuring device according to the first embodiment of the present invention will be described. First, the variable wavelength light source 1
2 generates tunable light. Next, the optical modulator 16 modulates the intensity of the variable wavelength light with the frequency of the modulation signal generated by the modulation power supply 14, and the variable wavelength light enters the reference optical device 40. The variable wavelength light transmits through the reference light device 40 and is photoelectrically converted by the photoelectric converter 22. The phase difference between the electric signal output from the photoelectric converter 22 and the modulation signal generated by the modulation power supply 14 is measured by the phase comparator 24. Based on this phase difference, the group delay time measurement unit 32
The group delay time of the reference light device 40 is measured. The wavelength measuring unit 36 records the content of the reference light device characteristic recording unit 34 (the wavelength of the variable wavelength light transmitted through the reference light device 40,
The wavelength of the variable wavelength light is measured from the relationship between the group delay time of the reference light device 40) and the group delay time of the reference light device 40.

According to the first embodiment of the present invention, the wavelength of the variable wavelength light generated by the variable wavelength light source 12 can be measured by measuring the group delay time of the reference light device 40. The group delay time of the reference light device 40 can be measured even when the wavelength of the variable wavelength light is swept largely. Therefore, even if the wavelength of the variable wavelength light is greatly swept, the wavelength of the variable wavelength light can be measured.

Second Embodiment In a second embodiment, the optical wavelength measuring device according to the first embodiment is incorporated in an optical characteristic measuring device of a DUT (Device Under Test). Hereinafter, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 3 is a block diagram showing a configuration of an optical wavelength measuring device according to a second embodiment of the present invention. The optical wavelength measuring device according to the second embodiment includes a variable wavelength light source 1
2. Modulation power supply 14, optical modulator 16, optical demultiplexer 18, photoelectric converter 22, phase comparator 24, group delay time measurement unit 3.
2. Reference light device characteristic recording unit 34, wavelength measuring unit 36,
Reference light device 40, DUT 50, photoelectric converter 62, D
A UT measurement phase comparison unit 64 is provided.

The optical demultiplexer 18 inputs the output of the optical modulator 16 to the reference optical device 40 and the DUT 50. DUT
Reference numeral 50 denotes an object for which a group delay time, chromatic dispersion, and the like are to be obtained. The photoelectric converter 62 converts the variable wavelength light transmitted through the DUT 50 into an electric signal. DUT measurement phase comparator 6
4 measures the phase difference between the electric signal output from the photoelectric converter 62 and the modulation signal generated by the modulation power supply 14. The group delay time of the DUT 50 can be measured based on the phase difference and the frequency of the modulation signal, and the chromatic dispersion of the DUT 50 can be measured based on the group delay time of the DUT 50 and the wavelength of the variable wavelength light.

Next, the operation of the optical wavelength measuring device according to the second embodiment of the present invention will be described. First, the variable wavelength light source 1
2 generates tunable light. Next, the optical modulator 16 modulates the intensity of the variable wavelength light with the frequency of the modulation signal generated by the modulation power supply 14. The variable wavelength light output from the optical modulator 16 is converted by the optical demultiplexer 18 into a reference light device 40
The light enters the UT 50.

The variable wavelength light transmitted through the reference light device 40 is photoelectrically converted by the photoelectric converter 22. The phase difference between the electric signal output from the photoelectric converter 22 and the modulation signal generated by the modulation power supply 14 is measured by the phase comparator 24. Based on this phase difference, the group delay time measuring unit 3
2 measures the group delay time of the reference light device 40. The wavelength measuring unit 36 records the contents of the reference light device characteristic recording unit 34 (the correspondence between the wavelength of the variable wavelength light transmitted through the reference light device 40 and the group delay time of the reference light device 40).
And the group delay time of the reference light device 40, the wavelength of the variable wavelength light is measured.

The variable wavelength light transmitted through the DUT 50 is photoelectrically converted by the photoelectric converter 62. Then, the DUT measurement phase comparator 64 measures the phase difference between the electric signal output from the photoelectric converter 62 and the modulation signal generated by the modulation power supply 14. The group delay time of the DUT 50 can be measured based on the phase difference and the frequency of the modulation signal.
The wavelength dispersion of the DUT 50 can be measured based on the group delay time and the wavelength of the variable wavelength light measured by the wavelength measuring unit 36.

According to the second embodiment, the variable wavelength light source 1
The wavelength can be measured even if the wavelength of the variable wavelength light generated by 2 is swept largely. Then, using the measurement result of the wavelength, D
The wavelength dispersion and the like of the UT 50 can be measured.

Third Embodiment A third embodiment is different from the first embodiment in that the variable wavelength light source 1
2 has a function of determining whether or not the wavelength of the variable wavelength light generated by Step 2 is a target value. Hereinafter, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 4 is a block diagram showing a configuration of an optical wavelength measuring device according to a third embodiment of the present invention. The optical wavelength measuring device according to the third embodiment includes a variable wavelength light source 1
2, power supply for modulation 14, optical modulator 16, photoelectric converter 22,
Phase comparator 24, group delay time measuring unit 32, reference light device characteristic recording unit 34, wavelength measuring unit 36, reference light device 4
0, target wavelength recording section 72, target group delay time calculation section 74,
A group delay time comparing section 76 and a wavelength comparing section 78 are provided.

The target wavelength recording section 72 records the target wavelength of the variable wavelength light and the time to reach the target.
FIG. 5 shows the recorded contents of the target wavelength recording section 72. As shown in FIG. 5A, the recorded content of the target wavelength recording unit 72 may be the correspondence between the time t from the start of the measurement and the target wavelength λ of the variable wavelength light. Note that λ0 in FIG.
Is the target wavelength of the variable wavelength light at the start of the measurement.
Further, the recorded content of the target wavelength recording section 72 may be a correspondence relationship between the time t from the start of the measurement and the target wavelength displacement Δλ of the variable wavelength light, as shown in FIG. 5B.

The target group delay time calculating section 74 calculates a target group delay time corresponding to the target wavelength from the recorded contents of the target wavelength recording section 72. Since the relationship between the wavelength of the transmitted light and the group delay time in the reference light device 40 is known, the target group delay time corresponding to the target wavelength can also be calculated. The calculation result of the target group delay time calculation unit 74 is as shown in FIG. However, FIG. 6A corresponds to FIG.
(B) corresponds to FIG.

The group delay time comparison unit 76 calculates the group delay time of the reference light device 40 measured by the group delay time measurement unit 32,
The target group delay time calculated by the target group delay time calculator 74 is compared with the target group delay time. If the comparison results in a match, the wavelength has been swept as intended. As a result of the comparison, if they do not match, it means that the wavelength has not been swept as intended. For example, as shown in FIG. 7, when the target group delay time is falling to the right and the group delay time is constant, the wavelength cannot be swept as intended. In addition, since the group delay time is constant, it can be seen that no wavelength sweep is performed.

The wavelength comparing section 78 compares the measurement result obtained by the wavelength measuring section 36 for measuring the wavelength of the variable wavelength light with the target wavelength recording section 7.
Compare the recorded contents of No. 2. In addition to comparing the group delay time with the target group delay time as in the group delay time comparison unit 76, a method of comparing the target wavelength with the actual wavelength to determine whether the sweep has been performed as the target value. There is also. As a result of the comparison,
If they match, the wavelength has been swept as intended. As a result of the comparison, if they do not match, it means that the wavelength has not been swept as intended. For example, as shown in FIG. 8, when the target wavelength is rising to the right and the measured wavelength is constant, the wavelength cannot be swept as intended. Moreover, it can be seen that no wavelength sweep is performed.

Next, the operation of the optical wavelength measuring device according to the third embodiment of the present invention will be described. First, the variable wavelength light source 1
2 generates tunable light. Next, the optical modulator 16 modulates the intensity of the variable wavelength light with the frequency of the modulation signal generated by the modulation power supply 14, and the variable wavelength light enters the reference optical device 40. The variable wavelength light transmits through the reference light device 40 and is photoelectrically converted by the photoelectric converter 22. The phase difference between the electric signal output from the photoelectric converter 22 and the modulation signal generated by the modulation power supply 14 is measured by the phase comparator 24. Based on this phase difference, the group delay time measurement unit 32
The group delay time of the reference light device 40 is measured. The wavelength measuring unit 36 records the content of the reference light device characteristic recording unit 34 (the wavelength of the variable wavelength light transmitted through the reference light device 40,
The wavelength of the variable wavelength light is measured from the relationship between the group delay time of the reference light device 40) and the group delay time of the reference light device 40.

The target group delay time calculating section 74 calculates the target group delay time based on the recorded contents of the target wavelength recording section 72. The group delay time comparison unit 76
Then, the measured group delay time of the reference light device 40 is compared with the target group delay time calculated by the target group delay time calculator 74.

Further, the wavelength comparing section 78 includes the wavelength measuring section 3
Reference numeral 6 compares the measurement result obtained by measuring the wavelength of the variable wavelength light with the recorded content of the target wavelength recording unit 72.

According to the third embodiment, the variable wavelength light source 1
The wavelength can be measured even if the wavelength of the variable wavelength light generated by 2 is swept largely. In addition, the group delay time comparing section 76 and the wavelength comparing section 78 can monitor whether the target wavelength sweep is being performed.

Fourth Embodiment In the fourth embodiment, the optical wavelength of the variable wavelength light in the first embodiment is controlled by the wavelength control unit 80, and the light is extracted to the outside by the optical demultiplexer 13. The entire wavelength measuring apparatus can be handled as a light source capable of appropriately controlling the wavelength. Hereinafter, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 9 is a block diagram showing a configuration of an optical wavelength measuring device according to the fourth embodiment of the present invention. The optical wavelength measurement device according to the fourth embodiment includes a variable wavelength light source 1
2, optical demultiplexer 13, modulation power supply 14, optical modulator 16, photoelectric converter 22, phase comparator 24, group delay time measuring unit 3
2. Reference light device characteristic recording unit 34, wavelength measuring unit 36,
A reference light device 40 and a wavelength controller 80 are provided.

The optical demultiplexer 13 is disposed between the variable wavelength light source 12 and the optical modulator 16, and takes out the light output from the variable wavelength light source 12 to the outside. That is, the entire light wavelength measuring device is used as one light source.

The wavelength control unit 80 controls the variable wavelength light source 1 based on the wavelength measured by the wavelength measurement unit 36 so that the wavelength of the variable wavelength light generated by the variable wavelength light source 12 matches the target wavelength.
2 is controlled. The control target of the wavelength control unit 80 differs depending on the configuration of the variable wavelength light source 12. Variable wavelength light source 12 is DF
In the case of a B laser, the wavelength control unit 80
Control the drive current and temperature of the If the variable wavelength light source 12 is an external cavity laser, the wavelength control unit 80 controls not only the drive current and temperature of the variable wavelength light source 12 but also the resonator length. FIG. 10 shows the configuration of the variable wavelength light source 12 when the variable wavelength light source 12 is an external cavity laser. The variable wavelength light source 12 has a laser diode 12a, a piezo element 12b, and a grating 12c. The laser diode 12a and the grating 12c form a resonator.

It should be noted that the wavelength control unit 80 is
A control method for adjusting the wavelength of the variable wavelength light generated by the variable wavelength light source 12 to the target wavelength based on the measured wavelength is well known. For example, it is also possible to take a difference between the wavelength measured by the wavelength measurement unit 36 and the target wavelength and perform general feedback control such as displacing the drive current, temperature, and resonance control length in proportion to the difference. Good.

Next, the operation of the optical wavelength measuring device according to the fourth embodiment of the present invention will be described. First, the variable wavelength light source 1
2 generates tunable light. Next, the optical modulator 16 modulates the intensity of the variable wavelength light with the frequency of the modulation signal generated by the modulation power supply 14, and the variable wavelength light enters the reference optical device 40. The variable wavelength light transmits through the reference light device 40 and is photoelectrically converted by the photoelectric converter 22. The phase difference between the electric signal output from the photoelectric converter 22 and the modulation signal generated by the modulation power supply 14 is measured by the phase comparator 24. Based on this phase difference, the group delay time measurement unit 32
The group delay time of the reference light device 40 is measured. The wavelength measuring unit 36 records the content of the reference light device characteristic recording unit 34 (the wavelength of the variable wavelength light transmitted through the reference light device 40,
The wavelength of the variable wavelength light is measured from the relationship between the group delay time of the reference light device 40) and the group delay time of the reference light device 40.

The wavelength control unit 80 controls the variable wavelength light source 12 based on the wavelength measured by the wavelength measurement unit 36 in order to adjust the wavelength of the variable wavelength light generated by the variable wavelength light source 12 to the target wavelength. . And the variable wavelength light source 12
The wavelength of the variable wavelength light generated by the above becomes equal to the target value. Then, the variable wavelength light generated by the variable wavelength light source 12 is extracted from the optical demultiplexer 13. Therefore, the entire optical wavelength measurement device becomes one light source.

According to the fourth embodiment of the present invention, the wavelength of the variable wavelength light generated by the variable wavelength light source 12 can be measured by measuring the group delay time of the reference light device 40. The group delay time of the reference light device 40 can be measured even when the wavelength of the variable wavelength light is swept largely. Therefore, even if the wavelength of the variable wavelength light is greatly swept, the wavelength of the variable wavelength light can be measured. Therefore, the wavelength controller 80 controls the variable wavelength light source 12 using the measurement result of the wavelength, so that the wavelength of the variable wavelength light generated by the variable wavelength light source 12 can be adjusted to the target value. Furthermore, by taking out the variable wavelength light whose wavelength is adjusted to the target value from the optical demultiplexer 13, the entire optical wavelength measuring device can be handled as one light source.

Fifth Embodiment FIG. 11 is a block diagram showing a configuration of an optical wavelength measuring device according to a fifth embodiment of the present invention. The optical wavelength measurement device according to the fifth embodiment includes a variable wavelength light source 12, a modulation power supply 14, an optical modulator 16, a photoelectric converter 22, an amplitude measurement unit 3,
3, reference light device characteristic recording unit 34, wavelength measuring unit 36,
A reference light device 40 is provided. The optical wavelength measuring device according to the embodiment of the present invention is for measuring the optical wavelength of the variable wavelength light source 12.

The variable wavelength light source 12 generates a variable wavelength light whose wavelength can be changed. By the variable wavelength light source 12,
The wavelength of the variable wavelength light can be swept. The modulation power supply 14 supplies the optical modulator 16 with a modulation signal having a frequency (modulation frequency) at which the variable wavelength light is to be modulated. Optical modulator 1
6 modulates the intensity of the variable wavelength light at the modulation frequency and enters the reference light device 40. The light modulator 16 generally has lithium niobate (LN), but may not include LN as long as the light intensity can be modulated.

The reference light device 40 transmits the light output from the light modulator 16. The correspondence between the wavelength of the light and the amplitude of the light after passing through the reference light device 40 is known.
The wavelength of the light incident on the reference light device 40 and the amplitude of the transmitted light (strictly speaking, the amplitude ratio between the electric signal obtained by photoelectrically converting the transmitted light and the electric signal output from the modulation power supply 14). FIG. 12 shows an example of the correspondence between the two. The example shown in FIG.
This is an example in which acetylene ( ¹² C ₂ H ₂ ) is used as the reference light device 40.

As shown in FIG. 12, when a certain wavelength is reached,
The amplitude decreases sharply. Therefore, if the amplitude of the light transmitted through the reference light device 40 is measured, the light wavelength of the variable wavelength light source 12 can be measured. The reference light device 40 is, for example, ¹² C ₂ H ₂ , ¹³ C ₂ H ₂ , H ¹³ C ¹⁴ N, argon, xenon, and krypton.

The photoelectric converter 22 converts the light transmitted through the reference light device 40 into an electric signal. The amplitude measurement unit 33
The amplitude of the light transmitted through the reference light device 40 is measured. That is, the amplitude of the electric signal output by the photoelectric converter 22 and
The amplitude ratio with the amplitude of the electric signal output from the modulation power supply 14 is measured. The reference light device characteristic recording unit 34 records the correspondence between the amplitude of the variable wavelength light transmitted through the reference light device 40 and the wavelength. The correspondence is as shown in FIG. 12 and is known. The wavelength measuring unit 36 stores the recorded contents of the reference light device characteristic recording unit 34 and the reference light device 4.
The wavelength of the variable wavelength light is measured from the amplitude of the light transmitted through 0.

Next, the operation of the optical wavelength measuring device according to the fifth embodiment of the present invention will be described. First, the variable wavelength light source 1
2 generates tunable light. Next, the optical modulator 16 intensity-modulates the variable wavelength light with the frequency of the modulation signal generated by the modulation power supply 14, and the variable wavelength light passes through the reference light device 40 and is photoelectrically converted by the photoelectric converter 22. . Then, the amplitude measuring unit 33 measures an amplitude ratio between the amplitude of the electric signal output from the photoelectric converter 22 and the amplitude of the electric signal output from the modulation power supply 14. The wavelength measuring unit 36 stores the recorded contents of the reference light device characteristic recording unit 34 (the correspondence between the wavelength of the variable wavelength light transmitted through the reference light device 40 and the amplitude), the amplitude of the light transmitted through the reference light device 40, and the like. Then, the wavelength of the variable wavelength light is measured.

According to the fifth embodiment of the present invention, the wavelength of the variable wavelength light generated by the variable wavelength light source 12 can be measured by measuring the amplitude of the light transmitted through the reference light device 40. The amplitude of the light transmitted through the reference light device 40 is
Measurement is possible even when the wavelength of the variable wavelength light is greatly swept.
Therefore, even if the wavelength of the variable wavelength light is greatly swept, the wavelength of the variable wavelength light can be measured.

Sixth Embodiment In a sixth embodiment, the optical wavelength measuring device according to the fifth embodiment is incorporated in an optical characteristic measuring device of a DUT (Device Under Test). Hereinafter, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 13 is a block diagram showing the configuration of the optical wavelength measuring device according to the sixth embodiment of the present invention. The optical wavelength measuring device according to the sixth embodiment includes a variable wavelength light source 1
2. Modulation power supply 14, optical modulator 16, optical demultiplexer 18, photoelectric converter 22, amplitude measuring unit 33, reference optical device characteristic recording unit 34, wavelength measuring unit 36, reference optical device 40, DU
T50, photoelectric converter 62, DUT measurement phase comparator 64
Is provided.

The modulation power supply 14 supplies the optical modulator 16 with a modulation signal having a frequency (modulation frequency) at which the variable wavelength light is to be modulated. The optical modulator 16 modulates the intensity of the variable wavelength light at the modulation frequency and enters the optical demultiplexer 18. The light modulator 16 generally has lithium niobate (LN), but may not include LN as long as the light intensity can be modulated. The optical demultiplexer 18 outputs the output of the variable wavelength light source 12 to the reference optical device 40 and the DU
It is incident on T50. The DUT 50 is an object for which a group delay time, chromatic dispersion, and the like are to be obtained. The photoelectric converter 62 is D
The variable wavelength light transmitted through the UT 50 is converted into an electric signal.
The DUT measurement phase comparator 64 measures the phase difference between the electric signal output from the photoelectric converter 62 and the modulation signal generated by the modulation power supply 14. The group delay time of the DUT 50 can be measured based on the phase difference and the frequency of the modulation signal.
DU based on group delay time of 50 and wavelength of variable wavelength light
The chromatic dispersion of T50 can be measured.

Next, the operation of the optical wavelength measuring device according to the sixth embodiment of the present invention will be described. First, the variable wavelength light source 1
2 generates tunable light. Next, the variable wavelength light is demultiplexed by the optical demultiplexer 18 and is incident on the reference light device 40 and the optical modulator 16.

The optical modulator 16 converts the variable wavelength light into the power supply 1 for modulation.
4 is intensity-modulated at the frequency of the modulation signal generated. The variable wavelength light output from the optical modulator 16 is incident on the DUT 50 via the optical demultiplexer 18. The variable wavelength light transmitted through the DUT 50 is photoelectrically converted by the photoelectric converter 62. DUT
The measurement phase comparator 64 measures the phase difference between the electric signal output from the photoelectric converter 62 and the modulation signal generated by the modulation power supply 14. The group delay time of the DUT 50 can be measured based on the phase difference and the frequency of the modulation signal, and the DUT 50 can be measured based on the group delay time of the DUT 50 and the wavelength of the variable wavelength light.
Can be measured.

The variable wavelength light transmitted through the reference light device 40 via the optical demultiplexer 18 is photoelectrically converted by the photoelectric converter 22. The amplitude measuring unit 33 determines the amplitude of the light transmitted through the reference light device 40 (strictly speaking, an electric signal obtained by photoelectrically converting the transmitted light by the photoelectric converter 22 and an electric signal output from the power supply 14 for modulation). Is measured). The wavelength measuring unit 36 includes a reference light device characteristic recording unit 34
(Correspondence relationship between the wavelength of the variable wavelength light transmitted through the reference light device 40 and the amplitude) of the reference light device 40
The wavelength of the tunable wavelength light is measured from the amplitude of the light transmitted through the.

According to the sixth embodiment, the variable wavelength light source 1
The wavelength can be measured even if the wavelength of the variable wavelength light generated by 2 is swept largely. Then, using the measurement result of the wavelength, D
The wavelength dispersion and the like of the UT 50 can be measured.

Seventh Embodiment The seventh embodiment is different from the fifth embodiment in that the variable wavelength light source 1
2 is added with a function of determining whether the wavelength of the variable wavelength light generated by the second optical element 2 has a target value. Hereinafter, portions similar to those of the fifth embodiment are denoted by the same reference numerals, and description thereof is omitted.

FIG. 14 is a block diagram showing the configuration of the optical wavelength measuring device according to the seventh embodiment of the present invention. The optical wavelength measurement device according to the seventh embodiment includes a variable wavelength light source 1
2, power supply for modulation 14, optical modulator 16, photoelectric converter 22,
Amplitude measurement unit 33, reference light device characteristic recording unit 34, wavelength measurement unit 36, reference light device 40, target wavelength recording unit 7
2. It includes a target amplitude calculator 75, an amplitude comparator 77, and a wavelength comparator 78.

The target wavelength recording section 72 records the target wavelength of the variable wavelength light and the time to reach the target.
The recorded contents of the target wavelength recording section 72 are the same as in the third embodiment, and will be described with reference to FIG. Target wavelength recording unit 7
As shown in FIG. 5A, the recorded content of No. 2 may be the correspondence between the time t from the start of the measurement and the target wavelength λ of the variable wavelength light. Note that λ0 in FIG. 5A is the target wavelength of the variable wavelength light at the start of the measurement. Further, the recorded content of the target wavelength recording section 72 may be a correspondence relationship between the time t from the start of the measurement and the target wavelength displacement Δλ of the variable wavelength light, as shown in FIG. 5B.

The target amplitude calculating section 75 includes the target wavelength recording section 7.
The target amplitude corresponding to the target wavelength is calculated from the recorded contents of 2. Since the relationship between the wavelength and the amplitude of the transmitted light in the reference light device 40 is known, the target amplitude corresponding to the target wavelength can also be calculated.

The amplitude comparing section 77 compares the amplitude of the variable wavelength light transmitted through the reference light device 40 measured by the amplitude meter 33 with the target amplitude which is the calculation result of the target amplitude calculating section 75. If the comparison results in a match, the wavelength has been swept as intended. If the comparison does not match,
This means that the wavelength has not been swept as intended. For example, when the amplitude measured by the amplitude meter 33 is constant, it can be understood that the wavelength is not swept.

The wavelength comparing section 78 compares the measurement result obtained by the wavelength measuring section 36 for measuring the wavelength of the variable wavelength light with the target wavelength recording section 7.
Compare the recorded contents of No. 2. In addition to comparing the group delay time with the target group delay time as in the group delay time comparison unit 76, there is a method of comparing the target wavelength with the actual wavelength. If the comparison results in a match, the wavelength has been swept as intended. As a result of the comparison, if they do not match, it means that the wavelength has not been swept as intended. For example, as shown in FIG. 8, when the target wavelength is rising to the right and the measured wavelength is constant, the wavelength cannot be swept as intended. Moreover, it can be seen that no wavelength sweep is performed.

Next, the operation of the optical wavelength measuring device according to the seventh embodiment of the present invention will be described. First, the variable wavelength light source 1
2 generates tunable light. Next, the optical modulator 16 modulates the intensity of the variable wavelength light with the frequency of the modulation signal generated by the modulation power supply 14, and the variable wavelength light enters the reference optical device 40. The variable wavelength light transmits through the reference light device 40 and is photoelectrically converted by the photoelectric converter 22. The amplitude measuring unit 33 calculates the amplitude of the variable wavelength light transmitted through the reference light device 40 (strictly speaking, the amplitude ratio between the electric signal obtained by photoelectrically converting the transmitted light and the electric signal output from the modulation power supply 14). ) Is measured. The wavelength measuring section 36 records the contents of the reference light device characteristic recording section 34 (the correspondence between the wavelength of the variable wavelength light transmitted through the reference light device 40 and the amplitude) and the variable wavelength light transmitted through the reference light device 40. From the amplitude, the wavelength of the variable wavelength light is measured.

The target amplitude calculator 75 calculates the target amplitude based on the recorded contents of the target wavelength recorder 72. The amplitude comparing unit 77 is configured to output the reference light device 40 measured by the amplitude meter 33.
Is compared with the target amplitude, which is the result of calculation by the target amplitude calculator 75.

Further, the wavelength comparing section 78 includes the wavelength measuring section 3
Reference numeral 6 compares the measurement result obtained by measuring the wavelength of the variable wavelength light with the recorded content of the target wavelength recording unit 72.

According to the seventh embodiment, the variable wavelength light source 1
The wavelength can be measured even if the wavelength of the variable wavelength light generated by 2 is swept largely. In addition, the amplitude comparison unit 77 and the wavelength comparison unit 78 can monitor whether the target wavelength sweep is being performed.

Eighth Embodiment In the eighth embodiment, the optical wavelength of the variable wavelength light in the fifth embodiment is controlled by the wavelength control unit 80 and extracted outside by the optical demultiplexer 13 so that the optical The wavelength measuring device can be handled as a light source capable of appropriately controlling the wavelength. Hereinafter, portions similar to those of the fifth embodiment are denoted by the same reference numerals, and description thereof is omitted.

FIG. 15 is a block diagram showing the configuration of an optical wavelength measuring device according to the eighth embodiment of the present invention. The optical wavelength measuring apparatus according to the eighth embodiment includes a variable wavelength light source 1
2, optical demultiplexer 13, modulation power supply 14, optical modulator 16, photoelectric converter 22, amplitude measuring unit 33, reference optical device characteristic recording unit 34, wavelength measuring unit 36, reference optical device 40, wavelength control unit 80 Is provided.

The optical demultiplexer 13 is disposed between the variable wavelength light source 12 and the optical modulator 16, and takes out the light output from the variable wavelength light source 12 to the outside. That is, the entire light wavelength measuring device is used as one light source.

The wavelength control unit 80 controls the variable wavelength light source 1 based on the wavelength measured by the wavelength measurement unit 36 so that the wavelength of the variable wavelength light generated by the variable wavelength light source 12 matches the target wavelength.
2 is controlled. The control target of the wavelength control unit 80 differs depending on the configuration of the variable wavelength light source 12. Variable wavelength light source 12 is DF
In the case of a B laser, the wavelength control unit 80
Control the drive current and temperature of the If the variable wavelength light source 12 is an external cavity laser, the wavelength control unit 80 controls not only the drive current and temperature of the variable wavelength light source 12 but also the resonator length. FIG. 10 shows the configuration of the variable wavelength light source 12 when the variable wavelength light source 12 is an external cavity laser. The variable wavelength light source 12 has a laser diode 12a, a piezo element 12b, and a grating 12c. The laser diode 12a and the grating 12c form a resonator.

It should be noted that the wavelength control unit 80 is
A control method for adjusting the wavelength of the variable wavelength light generated by the variable wavelength light source 12 to the target wavelength based on the measured wavelength is well known. For example, it is also possible to take a difference between the wavelength measured by the wavelength measurement unit 36 and the target wavelength and perform general feedback control such as displacing the drive current, temperature, and resonance control length in proportion to the difference. Good.

Next, the operation of the optical wavelength measuring device according to the eighth embodiment of the present invention will be described. First, the variable wavelength light source 1
2 generates tunable light. The optical modulator 16 intensity-modulates the variable wavelength light at the frequency of the modulation signal generated by the modulation power supply 14, and the variable wavelength light passes through the reference light device 40 and is photoelectrically converted by the photoelectric converter 22. And amplitude meter 3
Reference numeral 3 denotes the amplitude of light transmitted through the reference light device 40 (strictly speaking, the amplitude ratio between the electric signal obtained by photoelectrically converting the transmitted light by the photoelectric converter 22 and the electric signal output from the modulation power supply 14). Measure. The wavelength measuring unit 36 stores the recorded contents of the reference light device characteristic recording unit 34 (the correspondence between the wavelength of the variable wavelength light transmitted through the reference light device 40 and the amplitude), the amplitude of the light transmitted through the reference light device 40, and the like. Then, the wavelength of the variable wavelength light is measured.

The wavelength control unit 80 controls the variable wavelength light source 12 based on the wavelength measured by the wavelength measurement unit 36 in order to adjust the wavelength of the variable wavelength light generated by the variable wavelength light source 12 to the target wavelength. . And the variable wavelength light source 12
The wavelength of the variable wavelength light generated by the above becomes equal to the target value. Then, the variable wavelength light generated by the variable wavelength light source 12 is extracted from the optical demultiplexer 13. Therefore, the entire optical wavelength measurement device becomes one light source.

According to the eighth embodiment of the present invention, the wavelength of the variable wavelength light generated by the variable wavelength light source 12 can be measured by measuring the group delay time of the reference light device 40. The group delay time of the reference light device 40 can be measured even when the wavelength of the variable wavelength light is swept largely. Therefore, even if the wavelength of the variable wavelength light is greatly swept, the wavelength of the variable wavelength light can be measured. Therefore, the wavelength controller 80 controls the variable wavelength light source 12 using the measurement result of the wavelength, so that the wavelength of the variable wavelength light generated by the variable wavelength light source 12 can be adjusted to the target value. Further, by taking out the variable wavelength light whose wavelength is adjusted to the target value from the optical demultiplexer 13, the entire optical wavelength measuring device can be handled as one light source.

The above embodiment can be realized as follows. The CPU, hard disk, and media (floppy (registered trademark) disk, CD-ROM, etc.) having a reader for reading a medium having a program for realizing the above parts are read by a media reader of a computer equipped with the reader and installed on the hard disk. I do. Even with such a method, the above function can be realized.

[0093]

According to the present invention, the physical quantity of the variable wavelength light transmitted through the reference light device is measured by the reference light measuring means, and since the physical quantity and the wavelength of the variable wavelength light are known, the variable wavelength light is measured. Can be measured.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an optical wavelength measurement device according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of a correspondence relationship between a wavelength of light incident on a reference optical device 40 and a group delay time.

FIG. 3 is a block diagram illustrating a configuration of an optical wavelength measurement device according to a second embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of an optical wavelength measurement device according to a third embodiment of the present invention.

FIG. 5 is a diagram showing recorded contents of a target wavelength recording unit 72.

FIG. 6 is a diagram illustrating a calculation result of a target group delay time calculation unit 74;

FIG. 7 is a diagram showing a comparison between a group delay time and a target group delay time.

FIG. 8 is a diagram showing a comparison between a wavelength and a target wavelength.

FIG. 9 is a block diagram illustrating a configuration of an optical wavelength measurement device according to a fourth embodiment of the present invention.

FIG. 10 is a block diagram showing a configuration of the variable wavelength light source 12 when the variable wavelength light source 12 is an external cavity laser.

FIG. 11 is a block diagram illustrating a configuration of an optical wavelength measurement device according to a fifth embodiment of the present invention.

FIG. 12 shows a wavelength of light incident on a reference optical device 40,
FIG. 4 is a diagram illustrating an example of a correspondence relationship with the amplitude of transmitted light.

FIG. 13 is a block diagram illustrating a configuration of an optical wavelength measurement device according to a sixth embodiment of the present invention.

FIG. 14 is a block diagram illustrating a configuration of an optical wavelength measurement device according to a seventh embodiment of the present invention.

FIG. 15 is a block diagram showing a configuration of an optical wavelength measurement device according to an eighth embodiment of the present invention.

FIG. 16 is a block diagram showing a configuration of a chromatic dispersion measurement system of an optical device according to a conventional technique.

[Explanation of symbols]

 Reference Signs List 12 variable wavelength light source 14 modulation power supply 16 optical modulator 22 photoelectric converter 24 phase comparator 32 group delay time measuring unit 33 amplitude meter 34 reference optical device characteristic recording unit 36 wavelength measuring unit 40 reference optical device

Claims (19)

[The claims] 1. An optical wavelength measuring device for measuring the wavelength of variable wavelength light generated by a variable wavelength light source, wherein the variable wavelength light is transmitted, and the relationship between the physical quantity and the wavelength of the transmitted variable wavelength light is known. An optical wavelength measurement device comprising: a reference light device; and reference light measurement means for measuring a physical quantity of the variable wavelength light transmitted through the reference light device. 2. A modulation signal generating means for generating a modulation signal for providing a modulation frequency used for intensity modulation, and an optical modulation for supplying the variable wavelength light intensity-modulated at the modulation frequency to the reference optical device. The optical wavelength measuring apparatus according to claim 1, further comprising: a reference light measuring unit that measures a phase difference between the variable wavelength light transmitted through the reference optical device and the modulation signal. 3. A group delay time measuring means for measuring a group delay time of the reference light device based on the phase difference; a group delay time of the reference light device; and a group delay time of the variable wavelength light transmitted through the reference light device. Reference light device characteristic recording means for recording correspondence with a wavelength, and wavelength measuring means for determining the wavelength of the variable wavelength light from the recorded content of the reference light device characteristic recording means and the group delay time of the reference light device. The optical wavelength measuring device according to claim 2. 4. The optical modulation means also supplies the device under test with the variable wavelength light intensity-modulated at the modulation frequency, and a position of the variable wavelength light transmitted through the device under test and the modulation signal. The optical wavelength measurement device according to claim 2, further comprising a DUT measurement unit that measures a phase difference. 5. A group delay time measuring means for measuring a group delay time of the reference light device based on the phase difference, and a target of the reference light device based on a target wavelength of the variable wavelength light of the target variable wavelength light source. The optical wavelength measurement device according to claim 2, comprising: target group delay time calculating means for calculating a group delay time; and delay time comparing means for comparing the group delay time with the target group delay time. 6. The wavelength comparing means according to claim 3, further comprising: a wavelength comparing means for comparing a target wavelength of the variable wavelength light of said variable wavelength light source with a wavelength of said variable wavelength light obtained by said wavelength measuring means. Optical wavelength measurement device. 7. A wavelength control means for controlling the wavelength of the variable wavelength light generated by the variable wavelength light source based on the wavelength of the variable wavelength light obtained by the wavelength measurement means; and a variable wavelength light generated by the variable wavelength light source. The optical wavelength measuring device according to claim 3, further comprising: a light demultiplexing unit that extracts light from between the variable wavelength light source and the optical modulation unit. 8. The optical wavelength according to claim 2, wherein said reference optical device is any one of a dispersion compensating fiber, a dispersion compensating fiber Bragg grating, and a single mode optical fiber. measuring device. 9. The optical wavelength measuring apparatus according to claim 1, wherein said reference light measuring means measures the amplitude of said variable wavelength light transmitted through said reference light device. 10. A reference light device characteristic recording means for recording a correspondence between an amplitude and a wavelength of the variable wavelength light transmitted through the reference light device, a recording content of the reference light device characteristic recording means, and an amplitude of the variable wavelength light. The optical wavelength measuring apparatus according to claim 9, further comprising: a wavelength measuring unit that obtains a wavelength of the variable wavelength light from the following. 11. A modulation signal generating means for generating a modulation signal for providing a modulation frequency used for intensity modulation, and an optical modulation means for supplying the variable wavelength light intensity-modulated at the modulation frequency to a device under test. The optical wavelength measurement apparatus according to claim 9, further comprising: a DUT measurement unit configured to measure a phase difference between the variable wavelength light transmitted through the device to be measured and the modulation signal. 12. A target amplitude calculating means for calculating a target amplitude of the variable wavelength light transmitted through the reference light device based on a target wavelength of the variable wavelength light of the target variable wavelength light source; The optical wavelength measurement device according to claim 9, further comprising: an amplitude comparison unit that compares the two. 13. A wavelength comparing means according to claim 10, further comprising: a wavelength comparing means for comparing a target wavelength of said variable wavelength light of said variable wavelength light source with a wavelength of said variable wavelength light obtained by said wavelength measuring means. Optical wavelength measurement device. 14. A wavelength control means for controlling the wavelength of the variable wavelength light of the variable wavelength light source based on the wavelength of the variable wavelength light obtained by the wavelength measuring means; The optical wavelength measuring device according to claim 10, further comprising: a light demultiplexing unit that extracts light between a wavelength light source and the light modulating unit. 15. The reference light device according to claim ¹² , wherein said reference light device is ¹² C ₂ H ₂ , ¹³ C
_{^{2 H 2, H 13 C 14}} N, argon, any one of xenon and krypton, the light wavelength measuring apparatus according to any one of claims 9 to 14. 16. An optical wavelength measuring device for measuring the wavelength of variable wavelength light generated by a variable wavelength light source, wherein the variable wavelength light is transmitted, and the relationship between the physical quantity and the wavelength of the transmitted variable wavelength light is known. A reference light device; reference light measuring means for measuring a physical quantity of the variable wavelength light transmitted through the reference light device; and recording correspondence between the physical quantity and the wavelength of the variable wavelength light transmitted through the reference light device. An optical wavelength measuring apparatus comprising: a reference light device characteristic recording unit; and a wavelength measuring unit that determines the wavelength of the variable wavelength light from the recorded content of the reference light device characteristic recording unit and the measured physical quantity. 17. A variable wavelength light source for generating a variable wavelength light, a reference light device through which the variable wavelength light is transmitted, and a relation between a physical quantity and a wavelength of the transmitted variable wavelength light is known, and Reference light measuring means for measuring the physical quantity of the transmitted variable wavelength light, and a light wavelength measuring method for measuring the wavelength of the variable wavelength light of the optical wavelength measuring device, comprising: the physical quantity and the reference light device. A reference light device characteristic recording step of recording the correspondence with the wavelength of the transmitted variable wavelength light; and a wavelength measuring step of obtaining the wavelength of the variable wavelength light from the recorded contents of the reference light device characteristic recording means and the measured physical quantity. And a light wavelength measuring method comprising: 18. A variable wavelength light source for generating a variable wavelength light, a reference light device through which the variable wavelength light is transmitted, and a relation between a physical quantity and a wavelength of the transmitted variable wavelength light, and a reference light device, A reference light measuring means for measuring a physical quantity of the transmitted variable wavelength light, and a computer storing a program for causing a computer to execute a light wavelength measurement process for measuring the wavelength of the variable wavelength light of the optical wavelength measuring device having: A readable recording medium, comprising: a reference light device characteristic recording process for recording a correspondence between the physical quantity and the wavelength of the variable wavelength light transmitted through the reference light device; and a recording content of the reference light device characteristic recording unit. And a wavelength measurement process for determining the wavelength of the variable wavelength light from the measured physical quantity, and a program for causing a computer to execute Recording medium readable recording computer. 19. A variable wavelength light source for generating variable wavelength light, a reference light device through which the variable wavelength light is transmitted, and a relation between a physical quantity and a wavelength of the transmitted variable wavelength light is known, and Reference light measuring means for measuring a physical quantity of the transmitted variable wavelength light, and a program for causing a computer to execute an optical wavelength measurement process of measuring the wavelength of the variable wavelength light of the optical wavelength measurement device, comprising: A reference light device characteristic recording process for recording the correspondence between the physical quantity and the wavelength of the variable wavelength light transmitted through the reference light device; and the variable wavelength from the recorded contents of the reference light device characteristic recording means and the measured physical quantity. A wavelength measurement process for determining the wavelength of light, and a program for causing a computer to execute.