WO2007052702A1 - 波長変換装置 - Google Patents
波長変換装置 Download PDFInfo
- Publication number
- WO2007052702A1 WO2007052702A1 PCT/JP2006/321862 JP2006321862W WO2007052702A1 WO 2007052702 A1 WO2007052702 A1 WO 2007052702A1 JP 2006321862 W JP2006321862 W JP 2006321862W WO 2007052702 A1 WO2007052702 A1 WO 2007052702A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- fiber
- wavelength
- output
- wavelength conversion
- fundamental wave
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/35—Non-linear optics
- G02F1/353—Frequency conversion, i.e. wherein a light beam is generated with frequency components different from those of the incident light beams
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/02057—Optical fibres with cladding with or without a coating comprising gratings
- G02B6/02076—Refractive index modulation gratings, e.g. Bragg gratings
- G02B6/02195—Refractive index modulation gratings, e.g. Bragg gratings characterised by means for tuning the grating
- G02B6/02204—Refractive index modulation gratings, e.g. Bragg gratings characterised by means for tuning the grating using thermal effects, e.g. heating or cooling of a temperature sensitive mounting body
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/13—Stabilisation of laser output parameters, e.g. frequency or amplitude
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F2201/00—Constructional arrangements not provided for in groups G02F1/00 - G02F7/00
- G02F2201/30—Constructional arrangements not provided for in groups G02F1/00 - G02F7/00 grating
- G02F2201/305—Constructional arrangements not provided for in groups G02F1/00 - G02F7/00 grating diffraction grating
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/06—Construction or shape of active medium
- H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
- H01S3/067—Fibre lasers
- H01S3/0675—Resonators including a grating structure, e.g. distributed Bragg reflectors [DBR] or distributed feedback [DFB] fibre lasers
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/13—Stabilisation of laser output parameters, e.g. frequency or amplitude
- H01S3/131—Stabilisation of laser output parameters, e.g. frequency or amplitude by controlling the active medium, e.g. by controlling the processes or apparatus for excitation
- H01S3/1317—Stabilisation of laser output parameters, e.g. frequency or amplitude by controlling the active medium, e.g. by controlling the processes or apparatus for excitation by controlling the temperature
Definitions
- the present invention relates to a wavelength conversion device that obtains a stable high output by combining a fiber laser and a wavelength conversion element.
- a high-power visible light source with strong monochromaticity is required to realize a large display, a high-luminance display, and the like.
- red light sources red high-power semiconductor lasers used in DVD recorders and the like can be used as compact light sources with high productivity.
- green or blue light sources there is a demand for small, highly productive light sources that are difficult to achieve with semiconductor lasers and the like.
- a wavelength conversion device combining a fiber laser and a wavelength conversion element has been realized as a low-power visible light source.
- Small green and blue light sources that use semiconductor lasers as excitation light sources for exciting fiber lasers and nonlinear optical crystals as wavelength conversion elements are well known.
- FIG. 25 shows a schematic configuration of a conventional wavelength conversion device 10.
- Laser light from the fiber excitation semiconductor laser 1 is coupled by a lens 2 to an optical fiber 3 having a grating portion 6 formed therein.
- An optical resonator is constituted by the semiconductor laser 1 and the grating portion 6 of the optical fiber 3 by the laser beam reciprocating many times in this coupling.
- the laser light emitted from the optical resonator enters the wavelength conversion element 5 through the lens 4, is converted into second harmonic light, and is emitted with a surface force opposite to the incident surface of the wavelength conversion element 5.
- the wavelength band that can be converted by the wavelength conversion element 5 is as narrow as about 0. Inm.
- the wavelength that can be converted does not match, and a stable output cannot be obtained from the wavelength conversion element 5.
- the contracting member 7 expands and contracts the grating portion 6 of the optical fiber 3 in the length direction via the fixing portion 8 and the fixing portion 9.
- the wavelength of the light emitted from the optical resonator force composed of the semiconductor laser 1 and the optical fiber 3 changes, and the center wavelength of the incident light that can be converted by the wavelength conversion element 5 due to the temperature change of the wavelength conversion element 5
- a method has been proposed in which even if fluctuates, the system is made to follow it (see, for example, Patent Document 1 and Patent Document 2).
- the temperature of the grating unit is detected by the temperature sensing element, and the wavelength conversion element of the wavelength conversion element is included in the reflection wavelength band of the grating part at this temperature so that the convertible wavelength band of the wavelength conversion element is included.
- the temperature is also controlled. As a result, it has been shown that a stable light output from the wavelength conversion element can be obtained regardless of changes in the environmental temperature or the like (see, for example, Patent Document 4).
- the ratio of the wavelength change with respect to the temperature change inside the grating portion of the optical fiber and the wavelength conversion element is different from 0.005 nmZK and 0.05 nmZK, respectively.
- the wavelength selected in the grating portion and the wavelength that can be converted by the wavelength conversion element are greatly separated. Therefore, when trying to obtain low-power wavelength-converted light of several hundred mW or less, the method described in the above conventional example is effective, but when trying to obtain W-class high-power wavelength-converted light.
- the temperature rise inside the wavelength conversion element increases, and the amount of wavelength fluctuation becomes too large.
- Quasi-phase matching devices using lithium niobate crystals (LN) and lithium tantalate (LT) have a higher nonlinear optical constant than LBO crystals and KTP crystals, resulting in high efficiency.
- high-power wavelength conversion is possible.
- the QPM-LN element Since it is necessary to concentrate light energy in a narrow area, the crystal is more likely to be broken and deteriorated by the fundamental wave and the generated second harmonic than the KTP crystal.
- UV light that is the sum frequency of infrared light that is the fundamental wave and converted green light (second harmonic) It occurs even when (third harmonic) deviates from the phase matching condition. It has been found that this generated UV light absorbs green light and causes high-power green saturation and crystal breakdown. In this specification, this crystal breakage due to ultraviolet light (third harmonic) is called crystal breakage due to ultraviolet induced green light absorption (UVIGA), and is distinguished from conventional photodamage.
- UVIGA ultraviolet induced green light absorption
- Fig. 26 shows a conventional wavelength conversion element using LiNbO crystal with 5.Omol% Mg added.
- the input / output characteristic of the theoretical value is the curve CR, and the input and output are almost proportional.
- the input / output characteristics of the measured value are the curve CE, and in the section rl where the green light output is less than 1W, the force that the curve CR and the curve CE almost match.
- the curve CE is In the section r3 where the green light output falls off the curve CR and the green light output is 1.75 W or more, the curve CE deviates greatly from the curve CR power, and the green light output becomes unstable.
- the output of a conventional wavelength conversion element is 1 W or more, ultraviolet light-induced green light absorption occurs remarkably.
- Patent Document 1 Japanese Patent Application Laid-Open No. 2004-165389
- Patent Document 2 JP 2005-115192 A
- Patent Document 3 Japanese Patent Laid-Open No. 2005-181509
- Patent Document 4 Japanese Patent Laid-Open No. 2005-10340
- An object of the present invention is to provide a wavelength conversion device that can stably obtain high-power wavelength-converted light from a wavelength conversion element even when the environmental temperature changes.
- a wavelength conversion device is configured by optically connecting a fiber including a laser active substance and having two fiber gratings formed thereon and a laser light source that makes excitation light incident on the fiber. And a wavelength conversion element that converts the fundamental wave of the laser emitted from the laser resonator force into a harmonic, and the fiber grating is a first fiber grating on the laser light source side. And a second fiber grating on the wavelength conversion element side, and the temperature of the second fiber grating is adjusted according to the output of the harmonics output from the wavelength conversion element force.
- the temperature of the second fiber grating on the wavelength conversion element side is adjusted according to the output of the harmonics output from the wavelength conversion element force.
- the wavelength of the fundamental wave can be greatly shifted by greatly increasing the temperature of the fiber grating.
- the wavelength of the fundamental wave can be shifted so as not to deviate from the wavelength that can be converted by the wavelength conversion element, high-power wavelength-converted light can be stably obtained from the wavelength conversion element.
- FIG. 1 is a schematic diagram showing a configuration of a wavelength conversion device according to a first embodiment of the present invention.
- FIG. 2 is a schematic diagram showing a configuration of a wavelength conversion device according to a second embodiment of the present invention.
- FIG. 3 is a schematic diagram showing a configuration of a wavelength conversion device according to a third embodiment of the present invention.
- FIG. 4 is a schematic sectional view of the structure shown in FIG. 3 in which the vicinity of the fiber grating is enlarged along the optical axis.
- FIG. 6 is a diagram showing the measurement results of the amount of change in reflected wavelength at the fiber grating and the amount of change in phase matching wavelength at the wavelength conversion element with respect to the output of the fundamental wave in the third embodiment.
- FIG. 7 is a schematic cross-sectional view of an enlarged structure in which the vicinity of the fiber grating in a double-clad fiber is sectioned along the optical axis.
- FIG. 8 is a schematic structural cross-sectional view in which the vicinity of the fiber bag rating of the fiber used in the wavelength conversion device according to the fourth embodiment of the present invention is enlarged along the optical axis.
- FIG. 9 is a schematic structural cross-sectional view of the vicinity of the fiber bag rating of another fiber used in the wavelength converter according to the fourth embodiment of the present invention, which is enlarged along the optical axis.
- FIG. 10 is a schematic diagram showing a configuration of a wavelength conversion device according to a fifth embodiment of the present invention.
- FIG. 11 is an enlarged schematic view of the vicinity of the fiber grating and the wavelength conversion element of the wavelength converter shown in FIG.
- FIG. 13 is a schematic diagram showing the configuration of a wavelength conversion device according to a seventh embodiment of the present invention.
- FIG. 14 is a diagram showing a detailed configuration of the vicinity of the fiber grating region formed in the fiber used in the seventh embodiment of the present invention.
- FIG. 15 is a diagram showing the measurement results of the phase matching wavelength variation of the wavelength conversion element and the temperature rise with respect to the fundamental wave output.
- FIG. 16 is a schematic diagram showing the configuration of a wavelength conversion device according to a ninth embodiment of the present invention.
- FIG. 17 is a schematic diagram showing a configuration of a wavelength conversion device according to a tenth embodiment of the present invention.
- FIG. 18 is a schematic diagram showing a change in phase matching wavelength when the temperature of the wavelength conversion element is lowered.
- ⁇ 19 A schematic diagram showing the change in phase matching wavelength when the temperature of the wavelength conversion element rises. is there.
- FIG. 20 is a flowchart for explaining temperature control processing of the fiber grating by the determination circuit shown in FIG.
- FIG. 21 is a configuration diagram when temperature control of a wavelength conversion element is performed by a plurality of Peltier elements.
- FIG. 22 is a diagram showing the relationship between the distance of the incident surface force of the wavelength conversion element and the SHG output.
- FIG. 23 is a diagram showing the result of measuring the output characteristics of green light when the temperature of the wavelength conversion element is controlled by a plurality of Peltier elements.
- FIG. 24 is a configuration diagram when two Peltier elements are arranged in the vicinity of the exit surface where the SHG power deteriorates.
- FIG. 25 is a schematic configuration diagram of a conventional wavelength converter.
- FIG. 1 is a schematic diagram showing the configuration of the wavelength conversion device according to the first embodiment of the present invention.
- the wavelength conversion device shown in FIG. 1 includes a fiber laser 20, a lens 26, a wavelength conversion element 27, a beam splitter 28, a light receiving element 29, an output controller 30, and an excitation laser current source 31.
- the fiber laser 20 includes a laser light source 21 for making excitation light incident on a fiber (optical fiber) 14 and a fiber 14 in which a fiber grating 22 and a fiber grating 25 are formed.
- the excitation light from the laser light source 21 also enters one end force of the fiber 14.
- the incident excitation light is absorbed by the laser active substance contained in the fiber 14, and then the seed light of the fundamental wave is generated inside the fiber 14.
- the seed light of this fundamental wave is a fiber grating formed on the fiber 14.
- the laser beam is reflected back and forth many times in a laser resonator that uses the ing 22 and the fiber grating 25 as a pair of reflecting mirrors.
- the seed light is amplified by the laser active material contained in the fiber 14 to increase the intensity, leading to laser oscillation.
- the laser light source 21 is current-driven by an excitation laser current source 31.
- the laser light is output from the fiber laser 20, and the laser light enters the wavelength conversion element 27 through the lens 26.
- the laser beam from the fiber laser 20 becomes a fundamental wave, and this fundamental wave is converted into a harmonic by the nonlinear optical effect of the wavelength conversion element 27.
- the converted harmonics are partially reflected by the beam splitter 28, and the transmitted harmonics become the output light of the wavelength converter.
- the harmonics partially reflected by the beam splitter 28 are received by the light receiving element 29 and converted into an electric signal for monitoring the output light of the wavelength converter.
- the output controller 30 controls the excitation laser current source 31 and adjusts the drive current to the laser light source 21 so that the intensity of the converted signal becomes the intensity capable of obtaining the desired output of the wavelength converter. To do. Then, the intensity of the excitation light from the laser light source 21 is adjusted, the output intensity of the fundamental wave of the fiber laser 20 is adjusted, and as a result, the output intensity of the wavelength converted light output from the wavelength converter is adjusted.
- so-called auto power control hereinafter abbreviated as “APC”
- APC auto power control
- the core portion of the fiber 14 of the fiber laser 20 is doped with a rare earth element Yb as a laser active substance at a concentration of lOOOOppm.
- a semiconductor laser with a wavelength of 195 nm and a maximum output of 30 W is used as the laser source 21 for fiber excitation.
- the excitation light from the laser light source 21 enters the fiber 14, the excitation light is absorbed by the core portion, and stimulated emission with a wavelength of about 1060 nm occurs from the fiber 14 using the Yb level of the core portion.
- the stimulated emission light of about 1060 nm is amplified by a laser active material and travels through the fiber 14 to become a fundamental wave.
- the fiber grating 22 and the fiber grating 25 are used as reflection mirrors of the laser resonator, and the fundamental wave reciprocates between these reflection mirrors.
- the wavelength is selected.
- the reflection wavelength bandwidths of the fiber grating 22 and the fiber grating 25 are set to 1 to 5 nm and 0.1 nm, respectively. Therefore, the wavelength bandwidth of the fundamental wave is 0.1 nm, and this fundamental wave is output by 20 fiber lasers.
- the fundamental wave of about 1060 nm output from the fiber laser 20 enters the wavelength conversion element 27 via the lens 26.
- the wavelength conversion element 27 is an element that converts incident light into the second harmonic and outputs it.
- a periodically poled MgO: LiNbO crystal with a length of 10 mm is used.
- the wavelength that can be converted into a harmonic in the wavelength conversion element 27 is called a phase matching wavelength, and is set to about 1060 nm at 25 ° C. in the present embodiment. Therefore, the wavelength of the fundamental wave of the fiber laser 20 is approximately 1060 nm, which matches the phase matching wavelength, and the fundamental wave is converted to the second harmonic by the wavelength conversion element 27, and the green color with a wavelength of approximately 530 nm, which is the wavelength of 1Z2.
- the wavelength converter power is output as a laser.
- the wavelength conversion element 27 is temperature controlled with an accuracy of 0. Ore because the phase matching wavelength changes sensitively depending on the temperature of the element.
- a Peltier element is attached to the wavelength conversion element 27, and the temperature of the wavelength conversion element 27 is controlled with an accuracy of 0. Oe. In this way, a green laser of several hundred mW can be obtained with the output of the fundamental wave of the fiber laser 20 from 3 to 4 W.
- the wavelength of the fundamental wave of the fiber laser 20 matches the phase matching wavelength of the wavelength converter 27. It is difficult to let That is, when the output of the fundamental wave incident on the wavelength conversion element 27 increases to 3 to 4 W or more, the internal temperature of the wavelength conversion element 27 rapidly increases. In general, the ratio of the wavelength change with respect to the internal temperature of the fiber grating and the wavelength conversion element is 0.005 nmZK and 0.05 nmZK, respectively. As a result, the amount of shift due to the temperature rise of the fundamental wavelength and the temperature of the phase matching wavelength when the fundamental wave exceeds 5: LOW compared to when the fundamental wave has a low output of 3-4W. The shift amount due to the rise is far away. In addition, the shift amount exempts the range in which the wavelength conversion element 27 can be precisely controlled by the Peltier element.
- the internal temperature of the fiber grating 25 that selects the wavelength of the fundamental wave is further increased.
- the distance between the gratings is increased by raising the fiber grating 25 and thermally expanding it.
- the shift amount of the fundamental wavelength is increased, and the shift amount of the fundamental wavelength is matched with the shift amount of the phase matching wavelength due to the temperature rise.
- the rare earth element is doped in order to absorb the fundamental wave or a part of the excitation light in the fiber 14, and the fiber grating 25 is heated. That is, the cladding portion of Fino 14 is doped with a rare earth element Yb force of 20000 to 30000 ppm. Utilizing this Yb level, part of the fundamental leakage light and excitation light is absorbed to generate heat, and the fiber grating 25 is heated to raise the internal temperature.
- the core portion of the fiber 14 is doped with a rare earth element Yb as a laser active material at a concentration of lOOOOppm for absorbing the excitation light and generating the fundamental wave as described above. .
- a fundamental wave is generated mainly in the excitation light force, so the heating effect of the fiber grating 25 is small.
- the cladding portion of the fiber 14 is doped with the rare earth element Yb at a concentration of 20000 to 30000ppm!
- a part of the fiber grating can be absorbed and heated by the heat generated by the absorption to raise the temperature of the fiber grating.
- the magnitude of the output of the green laser output from the wavelength conversion element 27 is proportional to the magnitude of the output of the fundamental wave output from the fiber laser 20, the output of the fundamental wave of the laser or the excitation light is output.
- the amount of heat generated by absorbing a part of the light is proportional to the output of the green laser, and the temperature of the fiber grating 25 is adjusted according to the output of the green laser output from the wavelength conversion element 27. Will be.
- the temperature of the fiber grating can be increased more than before to increase the grating spacing, so that the wavelength of the fundamental wave is greatly shifted to a wavelength that can be converted by the wavelength conversion element 27. It is possible to obtain a stable W-class high output.
- the rare earth element doped into the fiber for heating is preferably at least one selected from Nd, Er, Dy, Pr, Tb and Eu. It is preferable to be doped at a concentration of ⁇ 3000 ppm. In this case, the selected rare earth By doping a similar element at a set concentration, the fiber grating can be further effectively heated.
- the rare earth element may be at least one selected from Yb, Ce, Tm, Ho, Gd, Y and La.
- the rare earth element is doped at a concentration of 20000 to 30000 ppm. It is preferable. Also in this case, the fiber grating can be further effectively heated by doping the selected rare earth element at the set concentration.
- the harmonics emitted from the wavelength conversion element 27 are green light having a wavelength of 510 to 550 nm, and the output of the green light is preferably 1 W or more, preferably 1.5 W or more. More preferred. In this case, as shown in Fig. 26, even if the green light output decreases due to ultraviolet light-induced green light absorption, the green light output after wavelength conversion is the same as the W when there is no output decrease due to ultraviolet light-induced green light absorption. It can be increased to a high output of the class.
- the harmonics emitted from the wavelength conversion element 27 may be blue light having a wavelength of 440 to 490 nm, and the output of the blue light is preferably 0.1 W or more and 0.15 W or more. More preferably. In this case, even when the blue light output is reduced due to ultraviolet light-induced green light absorption, the blue light output after wavelength conversion should be increased to a high output when there is no output drop due to ultraviolet light-induced green light absorption. Can do. Regarding the above points, the other embodiments are the same.
- FIG. 2 is a schematic diagram showing the configuration of the wavelength converter according to the second embodiment of the present invention.
- a fiber laser having a pair of fiber grating 22 and fiber grating 25 formed inside the fiber 14 as shown in FIG. 1 was used.
- a fiber (optical fiber) 15 having a fiber grating 22 formed in a part thereof, and a fiber (optical fiber) having a fiber grating 25 formed in a part thereof.
- a fiber laser 20a is formed by optically connecting 24 to the connection portion 16 to form an integrated structure.
- the fiber 15 that efficiently converts the pumping light into the fundamental wave and the fiber 24 that efficiently heats the fiber grating 25 that selects the wavelength of the fundamental wave are manufactured with optimum configurations.
- the cladding portion is not doped with rare earth elements, and therefore, the leakage light and excitation light of the fundamental wave are not absorbed in the cladding portion. Therefore, the excitation light can be efficiently converted to the fundamental wave with little light absorption loss. Furthermore, since the fiber 24 can increase the doping concentration of the rare earth element Yb in the core portion by 2 to 3 times compared to the fiber 14, the fiber grating 25 can be heated more efficiently.
- FIG. 3 is a schematic diagram showing the configuration of the wavelength conversion device according to the third embodiment of the present invention.
- a fiber (optical fiber) 19 having a fiber grating 22 formed in a part thereof, a fiber (optical fiber) 23 containing a laser active substance, and a part thereof.
- a fiber (optical fiber) 24 having a fiber grating 25 formed thereon is optically connected by a connection 16 and a connection 17.
- the fiber formed in this way is used for the fiber laser 20b.
- the fiber 23 that efficiently converts the pumping light into the fundamental wave and the fiber 24 that efficiently heats the fiber grating 25 that selects the wavelength of the fundamental wave are manufactured with optimal configurations. Can be used as an integral fiber.
- the fiber 19 is not doped with a rare earth element, there is almost no loss due to light absorption.
- the core portion of the fiber 23 is doped with rare earth element Yb as a laser active material at a concentration of 100 OOppm, and the core portion and the cladding portion of the fiber 24 are heated to heat the fiber grating 25.
- Rare earth element Yb force Doped at a concentration of S20000-30000ppm. If the wavelength selectivity of the fiber grating 22 is not strong compared to the fiber grating 25, the fiber 19 does not need to be doped with a rare earth element.
- the fiber laser 20a of FIG. An effect similar to that of the above configuration is obtained for the fiber laser 20 of FIG. That is, compared to the fiber 14 in FIG. 1, in the fiber 23 in which the excitation light is converted to the fundamental wave, the cladding portion is doped with a rare earth element. Does not absorb. Therefore, the excitation light can be efficiently converted to the fundamental wave with little light absorption loss. Furthermore, since the fiber 24 can increase the doping concentration of the rare earth element Yb in the core portion by 2 to 3 times compared to the fiber 14, the fiber grating 25 can be heated more efficiently. However, since the fiber 19 is not doped with rare earth elements, there is no loss in which the fundamental wave or a part of the excitation light is absorbed and converted into heat.
- the rare earth element doped into the fiber may be changed as follows.
- Fiber 23 is doped with rare earth element Yb at a concentration of 100 OOppm in the core as a laser active material.
- the reflection wavelength bandwidths of the fiber grating 22 and the fiber grating 25, which are a pair of reflection mirrors of the laser resonator of the fiber laser 20b, are set to lnm and 0.1 nm, respectively, and the wavelength selectivity at the fiber grating 25 is strengthened. Since it is not necessary to heat the fiber grating 22, the fiber 19 in which the fiber grating 22 is formed is not doped with a rare earth element.
- the fiber 24 that effectively heats the fiber grating 25 for selecting the wavelength of the fundamental wave is doped to absorb a part of the fundamental wave or the excitation light. That is, the rare earth element doped into the core and cladding of the fiber 24 is Nd, and the addition concentration is 1000 to 3000 ppm.
- FIG. 4 shows a schematic structural cross-sectional view in which the vicinity of the fiber grating 25 of the fiber 24 of FIG. 3 is enlarged along the optical axis.
- the core portion 42 and the cladding portion 43 of the fiber 24 are doped with a rare earth element Nd force of OOO to 3000 ppm. This rare earth element doping forms a level that absorbs the fundamental wave and excitation light.
- the outer side of the cladding portion 43 of the fiber 24 is covered with a coating portion 44.
- the laser oscillated by the laser active material in the fiber 23 propagates to the fiber 24 as the fundamental wave of the wavelength converter.
- the fundamental wave 45 propagating through the fiber 24 and the excitation light 46 are partially absorbed by the levels formed by the rare earth elements and converted to heat.
- the heat generated in the vicinity of the fiber grating 25 is directly The fiber grating 25 is heated to raise the temperature. When the temperature rises, the core portion 42 in which the fiber bag rating 25 is formed thermally expands, and the wavelength of the fundamental wave shifts to the longer wavelength side by extending the grating interval.
- the shift amount due to the temperature rise of the fundamental wave wavelength and the shift amount due to the temperature rise of the phase matching wavelength are greatly separated.
- the temperature rise of the fiber grating 25 can be increased several times to an order of magnitude more than in the case of the normal configuration. Then, the shift amount of the wavelength of the fundamental wave in the fiber grating 25 and the shift amount of the phase matching wavelength of the wavelength conversion element 27 can be substantially matched.
- the shift amount of the fundamental wavelength and the shift amount of the phase matching wavelength can be matched to achieve high output.
- a green laser of several W or more can be obtained stably.
- the output of the fundamental wave incident on the wavelength conversion element 27 is linearly polarized light.
- the fiber 19, fiber 23, and fiber 24 are all polarization-maintaining fibers, and the output of the fundamental wave incident on the wavelength conversion element 27 from the fiber laser 20b is linearly polarized light.
- the output of the fundamental wave may be linearly polarized by inserting a polarizer into the fiber laser 20b, in which one of the fibers 19, 23, and 24 is a normal fiber that is not polarization-maintaining.
- Temperature rise amount L1 in normal fiber grating with respect to fundamental wave output and this implementation Figure 5 shows the measurement results of the temperature rise L2 with the fiber grating 25 in the form of.
- the temperature rise L1 of a normal fiber grating increases in proportion to the fundamental wave output.
- the temperature rise L2 of the fiber grating 25 when the fundamental wave output is up to about 4 W increases in proportion to the slope slightly lower than usual.
- the temperature rise L2 increases rapidly with increasing fundamental wave output. The reason for this is considered to be the result that the effect of doping rare earth elements into the fiber appears remarkably when the output of the fundamental wave exceeds about 4.5 W. This effect is particularly noticeable when the core of Fino 24 is doped with rare earth element Nd at a concentration of 1000 to 3000 ppm.
- FIG. 6 shows the measurement results of the reflected wavelength variation L 3 at the fiber grating 25 and the phase matching wavelength variation L 4 at the wavelength conversion element 27 with respect to the fundamental wave output.
- the graph in Fig. 6 shows the amount of change in reflected wavelength reflecting the temperature rise of the fiber grating 25 with respect to the fundamental wave output in Fig. 5. Therefore, the temperature rise amount L2 of the fiber dulling 25 shown in FIG. 5 and the reflected wavelength change amount L3 of the fiber grating 25 shown in FIG. 6 show the same change with respect to the fundamental wave output. Recognize.
- the phase matching wavelength variation L4 in the wavelength conversion element 27 with respect to the fundamental wave output is also slightly larger than the reflected wavelength variation L3 in the fiber grating 25 and shows the same change tendency.
- the shift amount of the fundamental wavelength in the fiber grating 25 and the shift amount of the phase matching wavelength of the wavelength conversion element 27 are substantially the same.
- the temperature of the fundamental wave and the phase-matched wavelength are matched by finely adjusting the temperature with the Bercher element attached to the wavelength conversion element 27.
- a laser can be obtained stably.
- a 2.3 W green laser was stably obtained when the output of the fundamental wave was 9 W.
- a fiber having a double clad structure may be used as the fiber.
- Fig. 7 shows a schematic structural cross-sectional view of the fiber cladding 25 in the double-clad fiber 50 in the vicinity of the fiber grating 25 and enlarged along the optical axis.
- the fiber 50 of the double clad structure has a higher refractive index in the inner clad portion 53 of the two clad portions 53 and 57 than in the outer clad portion 57.
- the pumping light 56 can be more efficiently confined in the inner cladding portion 53 and propagated in the fiber 50.
- the outer periphery of the outer cladding portion 57 is covered with a covering portion 54.
- the fiber grating 25 is heated by absorbing a part of the fundamental wave 55 or the pumping light 56 propagating through the core portion 52, the clad portion 53 and the clad portion of the fiber 50 of this double clad structure are heated.
- a structure in which at least one of 57 is doped with a rare earth element as described above may be used. With this configuration, the shift amount of the wavelength of the fundamental wave 55 and the shift amount of the phase matching wavelength of the wavelength conversion element 27 are matched, and a high-power green laser of several W or more can be stably obtained.
- a configuration similar to that of the fiber 14 of Fig. 1 manufactured as a single continuous fiber 19, fiber 23, and fiber 24 may be used.
- the cladding portion of the fiber 14 is not doped with rare earth elements but only the core portion is doped with rare earth elements, at least one element of Nd, Er, Dy, Pr, Tb, and Eu rare earth elements is doped at less than lOOOppm.
- the heating effect of the fiber grating 25 may be slightly reduced.
- the amount of the rare earth element doped into the fiber is below the lower limit, the amount of light absorbed is small, so the heating effect of the fiber grating is small. Conversely, if the amount of rare earth elements doped in the fiber exceeds the upper limit, the fiber grating will be overheated and the internal temperature will become unstable, making it impossible to control the visible light output of the wavelength converter.
- FIG. 8 is a schematic structural cross-sectional view of the vicinity of the fiber grating of the fiber used in the wavelength converter according to the fourth embodiment of the present invention, which is enlarged along the optical axis.
- the fiber 60 of FIG. 8 is obtained by covering the fiber 24 of FIG. 4 described in the third embodiment with a recoat portion 47 outside the cladding portion 43 in the region where the fiber rating 25 is formed.
- the other configurations of the present embodiment are the same as those of the third embodiment. Therefore, the detailed description will be omitted and the characteristic part will be mainly described.
- the re-coating portion 47 is made of a material that absorbs a part of the output of the fundamental wave 45 or the excitation light 46.
- a mixture of a fluorine-based polymer and a light absorber having a particle size of several meters is applied around the cladding portion 43 of the fiber 60 in FIG.
- the light absorber bubbles such as air, carbon, rare earth oxides, and the like, which are desired, were mixed in a fluorine polymer in an amount of about 1 to 5% by volume. In this case, the light reflected by the fiber grating 25 of the fundamental wave 45 or the partial re-covering portion 47 of the excitation light 46 is absorbed.
- the fiber grating 25 Since the re-coated portion 47 serves as a heating portion, the fiber grating 25 is heated. If this is done, the temperature rises in the fiber grating 25 and the dulling interval is widened, so the wavelength of the fundamental wave is shifted to the longer wavelength side.
- the cladding portion 43 of the fiber 60 doped with 1000 to 300 Oppm of rare earth element Er was used.
- the fiber grating 25 was heated by absorbing part of the output of the filter, the fundamental wave 45 or the pumping light 46 by the cladding part 43. .
- FIG. 9 is a schematic structural cross-sectional view showing an enlarged vicinity of the fiber grating of another fiber used in the wavelength converter according to the fourth embodiment of the present invention along the optical axis.
- the outer periphery of the outer cladding portion 57 located in the region where the fiber rating 25 is formed is covered by the re-coated portion 47. You may make it cover.
- the fiber 65 in FIG. 9 is obtained by doping the inner cladding portion 53 with 1000 to 3000 ppm of rare earth element Er, and further forming a recoated portion 47 on the outer periphery of the outer cladding portion 57 in the vicinity of the fiber grating 25. .
- the re-coated portion 47 in Figs. 8 and 9 generates heat by absorbing light, but is made of a flame-retardant material. Therefore, materials with sufficient consideration for safety are selected as materials for the fibers 60 and 65, and high reliability can be obtained.
- a material having a refractive index in the range of 1.37 to L43 is used as the material of the re-coated portion 47.
- a material having a refractive index in the range of 1.37 to L43 is used as the material of the re-coated portion 47.
- the refractive index of a normal coating material is higher than that of 1.35 to L36, so that the reflected light of the fundamental wave and a part of the excitation light are more easily absorbed. That is, it is possible to heat the fiber grating 25 by absorbing an optimum amount of reflected light of the fundamental wave and a part of the excitation light.
- the refractive index exceeds 1.43 the fiber 60 and the fiber 65 absorb the excitation light too much and are heated too much, or the loss of the excitation light becomes too large.
- the force described using Nd and Er for the core portion of the fiber 24 or the like is selected from Nd, Er, Dy, Pr, Tb, and Eu for the core portion.
- At least one rare earth element doped to a concentration of 1000-3000 ppm or at least one rare earth element selected from Yb, Ce, Tm, Ho, Gd, Y and La is 20 000-30000 ppm The same effect can be obtained even if the composition is doped to a concentration of.
- Nd, Er, Dy, Pr, and Nd are applied to the cladding portion of the fiber 24 described using Nd and Er for the cladding portion of the fiber 24 and the like.
- At least one element of rare earth elements of Tb and Eu is doped at a rate of 1000 to 3000 ppm, or at least one element of rare earth elements of Yb, Ce, Tm, Ho, Gd, Y and La is 20000 to 30000 ppm If the structure is doped at this ratio, the heating effect is further enhanced.
- the fiber grating 25 cannot be heated effectively. Conversely, if the amount of rare earth elements doped in the fiber exceeds the upper limit, the fiber grating will be overheated and the temperature will become unstable, making it impossible to control the visible light output of the wavelength converter.
- the rare-earth element doped in the core portion and the clad portion of the fiber 24 or the like can obtain the same effects as those of the present embodiment even when a plurality of elements are combined.
- levels other than those formed by a single element are formed.
- the level is formed so that the energy gap difference between these levels is 1. OeV or less, the transition between the levels below 1. OeV changes to thermal energy, and the heating effect of the fiber grating 25 Can be increased.
- FIG. 10 is a schematic diagram showing the configuration of the wavelength conversion device according to the fifth embodiment of the present invention.
- FIG. 11 is an enlarged view of the vicinity of the fiber grating 25 and the wavelength conversion element 27 of the wavelength conversion device shown in FIG. FIG.
- the wavelength converter that works on the fifth embodiment shown in FIG. 10 includes a wavelength conversion element 27 and a fiber laser 20c that outputs a laser beam that is an output of a fundamental wave that is input to the wavelength conversion element 27.
- the configuration shown in Fig. 3 is adopted, and by detecting a part of the fundamental wave output with the fiber laser 20c, the intensity of the light output after wavelength conversion can be controlled more accurately, and more stable APC It is configured to be able to operate.
- a part 32 of the fundamental wave output extracted from the fiber 23 by a coupler or the like is detected by the light receiving element 33 and taken into the output controller 30a.
- the fundamental wave output the light reflected by the fiber grating 25 is taken out and becomes part 34 of the fundamental wave output, and part 34 of the fundamental wave output is detected and output by the light receiving element 35. It is configured to be loaded into the controller 30a.
- a method for detecting the output of the fundamental wave either of the fundamental wave outputs 32 and 34 may be detected, and the light receiving elements 33 and 35 corresponding thereto may be used.
- the present embodiment further includes means for suppressing the temperature rise of the wavelength conversion element 27. As a result, the amount of change in the phase matching wavelength in the wavelength conversion element 27 is further reduced. In addition, even when the wavelength converter performs a W-class high-power operation, the wavelength of the fundamental wave output of the fiber laser 20c and the phase matching wavelength can be more easily and stably matched.
- the wavelength conversion element 27 shown in FIG. 11 was cooled by the temperature control element, and here, the Peltier element 37 was used as the temperature control element.
- a shared holding base 38 is used as a holding base for the wavelength converting element 27 and the fiber grating 25 so that heat 58 generated in the Peltier element 37 is transferred to the fiber grating 25 by cooling the wavelength converting element 27. .
- the common holding base 38 and the holding block 39 of the fiber grating 25 are surrounded by an insulating grease so that the heat generated in the Peltier element 37 does not diffuse to the surroundings. 18 covered. In this way, it occurs in the Peltier element 37 shown in FIG.
- the heat 58 is efficiently transferred to the formation region of the fiber grating 25 through the holding base 38 and the holding block 39, and effectively heats the fiber grating 25.
- the output 48 of the fundamental wave shown in FIG. 11 generated in the fiber 23 and the fiber 24 in FIG. 10 is increased to obtain a stable high-power light 49 from the wavelength conversion element 27.
- the green laser is operating at a high output of several hundreds mW
- the internal temperature of the wavelength conversion element 27 is greatly increased when operating at a high output of class W. It is difficult to match the wavelength of the fundamental wave output, which is a wave, of 48. Therefore, as described in the third embodiment, the fiber 24 is doped with rare earth elements, and the temperature of the fiber darling 25 is increased to several times that of the conventional one, so that the fundamental wave output 48 wave is obtained. The length is shifted to a long wavelength to bring it closer to the phase matching wavelength of the wavelength conversion element 27.
- the holding base 38 is made of copper which is a good heat conductor. The entire surface of the holding base 38 is coated with an insulating resin 18 so that heat is not diffused from the copper cap.
- the holding block 39 is also made of a metal made of brass or a material having a thermal conductivity equivalent to that of the metal.
- the temperature rise of the wavelength conversion element 27 can be suppressed by effectively moving the heat 58 to the fiber grating 25. .
- FIG. 12 is a schematic diagram mainly showing a configuration of an optical system for coupling the fiber grating and the wavelength conversion element of the wavelength conversion device according to the sixth embodiment of the present invention.
- the basic configuration of this embodiment is the same as that shown in FIG. What is different from FIG. 10 is the part of the optical system that couples the output light of the fiber laser 20c and the wavelength conversion element 27.
- this optical system is a force that is only the lens 26.
- this optical system is configured such that the lens 26 is provided with a cylindrical lens 36 to suppress an increase in the internal temperature of the wavelength conversion element 27. To do.
- FIG. 12 shows the wavelength from the output part of the fiber laser 20c, that is, the fiber grating 25.
- the top view of the configuration up to the output side of the conversion device, that is, the output side of the wavelength conversion element 27 is shown.
- the fundamental wave of the fiber laser from the fiber grating 25 formed in the fiber 24 is incident on the wavelength conversion element 27 via the lens 26 and the cylindrical lens 36.
- the incident fundamental wave is converted by the wavelength conversion element 27 into the second harmonic of the fundamental wave by the nonlinear optical effect. This converted second harmonic output becomes the output light of the wavelength converter.
- the cylindrical lens 36 can move along a direction 59 parallel to the optical axis corresponding to the intensity of the fundamental wave output, and the fundamental wave of the wavelength conversion element 27 corresponds to this movement.
- the width 69 of the light beam at the incident surface of the output increases.
- the movement is performed by attaching a cylindrical lens 36 to a piezoelectric element that moves in response to a signal that changes in accordance with the magnitude of the fundamental wave output, a lens actuator that uses electromagnetic induction, or the like. That is, when the output of the fundamental wave is low, the cylindrical lens 36 moves along the direction 59 parallel to the optical axis to a position where the width 69 of the light beam at the end face of the wavelength conversion element 27 is minimized.
- the fundamental wave output part 32 or the fundamental wave output part 34 is detected by the light receiving element 33 or the light receiving element 35 to output the fundamental wave.
- the cylindrical lens 36 reduces the width 69 of the light beam by moving slightly away from the wavelength conversion element 27 along the direction 59 parallel to the optical axis, for example, according to the magnitude of the increase in the fundamental wave output. Expand. In this way, the intensity of the light beam per unit volume in the wavelength conversion element 27 does not become too large! /, And thus the temperature rise inside the wavelength conversion element 27 can be suppressed. .
- the position of the cylindrical lens 36 may be changed by detecting the intensity of the fundamental wave output and changing the voltage applied to the piezoelectric element in accordance with the magnitude of the intensity.
- a plurality of cylindrical lenses 36 having different focal lengths are prepared, and a plurality of cylindrical lenses 36 are replaced and used in accordance with the intensity of the fundamental wave output.
- FIG. 13 shows the present invention. It is the schematic which shows the structure of the wavelength converter by 7th Embodiment of this.
- FIG. 13 has substantially the same configuration as FIG. 10, and both the fiber grating 25 and the wavelength conversion element 27 of the fiber laser 20d can perform temperature control using Peltier elements 66 and 67 as temperature control means. Is different. As a whole of the wavelength converter, each operation including the Peltier elements 66 and 67 is controlled by the output controller 30b.
- a part of the output of the wavelength converter is detected by the light receiving element 29, and the output of the fundamental wave 45 is detected by the light receiving elements 33 and 35.
- the data indicating the relationship between the fundamental wave output and the wavelength converter output, the shift amount of the fundamental wave wavelength relative to the fundamental wave output, and the phase matching wavelength
- the shift amount data is measured in advance, and the data is stored in the output controller 30b as a table.
- the fiber grating 25 is heated by the Peltier element 66 under the control of the output controller 30b or the wavelength by the Peltier element 67 so that the conversion efficiency at the wavelength conversion element 27 is maximized.
- the conversion element 27 is cooled.
- the difference between the shift amount of the fundamental output wavelength and the shift amount of the phase matching wavelength is finally reduced to a stable W-class high-power operation.
- FIG. 14 is a diagram showing a detailed configuration in the vicinity of the region of the fiber grating 25 formed in the fiber 70, and shows a configuration of the fiber 70 in which the vicinity of the fiber grating 25 is held by the holding member 63.
- the holding member 63 is fixed by being bonded to the covering portion 44 of the fiber 70 with an adhesive 64.
- the holding member 63 generates heat by absorbing light reflected by the fiber grating 25 in the fundamental wave 45 and leakage light of the excitation light 46.
- the coefficient of thermal expansion of the holding member 63 is larger than the coefficient of thermal expansion of the core portion 42 and the cladding portion 43 of the fiber, so that the holding member 63 passes through the adhesive 64 due to the thermal expansion.
- the covering portion 44 is pulled in the left-right direction 61 shown in FIG. Accordingly, the fiber grating 25 is subjected to tensile stress in the outer direction 62. As a result, the grating interval increases, and the wavelength of the fundamental wave 45 shifts to the longer wavelength side.
- the internal temperature of the wavelength conversion element Since the phase matching wavelength greatly changes with a large increase in the degree, it is difficult to achieve stable high output operation that is difficult to match with the wavelength of the incident fundamental wave.
- the fiber 70 when the fiber 70 is used, the effect of the stress on the holding member 63 described above and the heating effect of the fiber grating 25 by the optimum doping of the rare earth element to the fiber 70 are used for the grating. As the interval becomes larger, the wavelength of the fundamental wave 45 shifts to the longer wavelength side. As a result, the difference between the shift amount of the fundamental wavelength and the shift amount of the phase matching wavelength can be reduced.
- the holding member 63 in FIG. 14 is made of a flame-retardant material, and the fiber 70 is selected from a material that gives sufficient consideration to safety. Further, in FIG. 14, only the region where the fiber grating 25 is formed is coated on the outside of the cladding portion 43 of the fiber 70, and a recoating portion may be provided in this portion.
- the laser output after wavelength conversion is controlled based on data stored in a table stored in advance. Since the configuration of the entire wavelength conversion device of the eighth embodiment is the same as the configuration shown in FIG. 13, the illustration thereof is omitted, and the control operation will be described with reference to FIG.
- the output light of the wavelength conversion device is detected by the light receiving element 29, and a part 32, 34 of the fundamental wave output can be detected by the light receiving elements 33, 35.
- the fiber grating 25 and the wavelength conversion element 27 of the fiber 24 can be controlled by Peltier elements 66 and 67, respectively.
- the light receiving elements 29, 33, and 35 and the penoleche elements 66 and 67 are all connected to the output controller 30b and controlled as a whole.
- the amount of change in the reflected wavelength of the fiber grating with respect to the fundamental wave output changes with a change of 0.0 InmZK, so the fundamental wave output is 5 to: LOW, and the internal temperature of the wavelength conversion element is If it rises, the amount of change in the phase matching wavelength of the wavelength conversion element, which changes with a change of 0.05 nmZK, becomes very large and adjustment becomes difficult.
- the core portion or the cladding portion of the fiber 24 is doped with a rare earth element so that the output of the fundamental wave or the excitation light is reduced.
- the fiber grating 25 is heated and the internal temperature is increased by absorbing the Yes.
- the internal temperature of the region where the fiber grating is formed rises more than before, so the amount of change in the reflected wavelength at the fiber grating 25 is as shown in Fig. 6.
- a larger change than the conventional one can be obtained.
- the amount of change in the phase matching wavelength of the wavelength conversion element 27 and the amount of change in the reflected wavelength of the fiber grating 25 are as shown in FIG. It can be configured to have substantially the same amount of change with respect to the output. Further, by controlling the temperature using the Peltier elements 66 and 67, the wavelength of the fundamental wave selected by the fiber grating 25 can be accurately matched to the phase matching wavelength of the wavelength conversion element 27. As a result, an infrared fundamental wave of about 1060 nm is converted to the second harmonic by the wavelength conversion element 27, and a green W-class high-power light of 530 nm is obtained.
- the amount of change in the reflected wavelength at the fiber grating 25 with respect to the output of the fundamental wave is taken using the environmental temperature as a parameter.
- the amount of phase matching wavelength change in the wavelength conversion element 27 with respect to the fundamental wave output is taken.
- the wavelength conversion element 27 for the fundamental wave output obtained only by the phase matching wavelength variation L5 of the wavelength conversion element 27 for the fundamental wave output 27 It is preferable to store data such as the temperature rise width L6 in advance and store it as stored data, while referring to the tableed data.
- the temperature can be controlled with higher accuracy.
- FIG. 16 is a schematic diagram showing the configuration of the wavelength converter according to the ninth embodiment of the present invention.
- a temperature sensor 68 is provided on a holder for the wavelength conversion element 27, and the temperature of the fiber grating 25 is controlled by a Peltier element 66 or the like. That is, in this embodiment, the wavelength conversion element 27 shown in the seventh embodiment is controlled.
- a temperature sensor 68 detects the temperature of the wavelength conversion element 27 instead of the Peltier element 67 that performs the above operation. With such a configuration, as shown in FIG. 15, it is possible to grasp the phase matching wavelength change amount of the wavelength conversion element 27 and the element temperature rise with respect to the output of the fundamental wave.
- the wavelength of the fundamental wave that is the incident wave can be matched with the phase matching wavelength of the wavelength conversion element 27. Since the wavelength of this fundamental wave is controlled with high precision by the Peltier element 66 that controls the temperature of the fiber grating 25, as described above, a W-class visible light laser can be stably output from this wavelength converter. .
- FIG. 17 is a schematic diagram showing the configuration of the wavelength converter according to the tenth embodiment of the present invention.
- the wavelength conversion apparatus shown in FIG. 17 includes a fiber laser 20e, a lens 26, a wavelength conversion element 27, a beam splitter 28, a light receiving element 29, an output controller 30c, an excitation laser current source 31, and Peltier elements 66 and 67.
- the output controller 30c is a force that also controls the Peltier element 67 so that the temperature of the wavelength conversion element 27 becomes constant. If the temperature control of the wavelength conversion element 27 is not performed, the Peltier element 67 may be omitted. .
- the fiber laser 20e is composed of a laser light source 21 for making excitation light incident on a fiber (optical fiber) 14a, and a fiber 14a in which a fiber grating 22 and a fiber grating 25 are formed. .
- the core portion of the fiber 14a is doped with rare earth element Yb as a laser active substance at a concentration of lOOOOppm.
- the clad is not doped with rare earth elements.
- the temperature of the fiber grating 25 is controlled by the Bellecher element 66. Except for these points, the fiber laser 20e is configured in the same manner as the fiber laser 20 shown in FIG. 1 and operates in the same manner.
- the output controller 30c includes an AZD converter 71, a determination circuit 72, a DZA converter 73, a PWM signal generator 74, a current-output value table 75, and a register 76.
- the output controller 30c uses the Peltier element 66 to control the temperature of the fiber grating 25. If necessary, a thermistor for measuring the temperature at a predetermined location in the wavelength conversion device may be provided.
- each setting value at the time of shipment from the factory is stored in advance, and the output value of green light with respect to the current value supplied to the laser light source 21 is stored in a table format. These values serve as reference values for control.
- the register 76 is used to temporarily store a current value and an output value used during control.
- the output value of the green light to be output by the wavelength converter is determined according to the light amount control signal LC which is an external signal.
- the current-output value table 75 receives the light quantity control signal LC and notifies the judgment circuit 72 of the output value of the green light set by the light quantity control signal LC.
- the determination circuit 72 is also configured with a microcomputer equal force. With reference to the current output value table 75, the current value corresponding to the output value set by the light quantity control signal LC is converted to the excitation laser current via the DZA converter 73. Notify source 31.
- the light receiving element 29 receives the green light partially reflected by the beam splitter 28, and outputs an output detection signal, which is a voltage signal corresponding to the magnitude of the received green light, to the AZD converter 71.
- the AZD converter 71 converts the analog output detection signal into a digital output detection signal and outputs the digital detection output signal to the determination circuit 72.
- the determination circuit 72 controls the temperature of the fiber grating 25 by using the Beltier element 66 according to the output detection signal.
- Fig. 18 is a schematic diagram showing changes in the phase matching wavelength when the temperature of the wavelength conversion element 27 is decreased.
- Fig. 19 shows changes in the phase matching wavelength when the temperature of the wavelength conversion element 27 is increased. It is a schematic diagram to represent.
- the determination circuit 72 instructs the PWM signal generator 74 to output a PWM signal for setting the temperature of the fiber grating 25 to the standby temperature.
- the PWM signal generator 74 uses the Peltier element 66 to adjust the temperature of the fiber grating 25 to the standby temperature.
- the standby temperature for example, a temperature that is 85 to 95% of the phase matching temperature at which the harmonic intensity reaches a peak and is lower than the phase matching temperature can be used.
- the temperature of the fiber grating 25 is controlled to the standby temperature, and the green light is output from the standby position where the green light output from the wavelength conversion element 27 is 85 to 95% of the peak output.
- the characteristic curve of the phase matching wavelength with respect to the green light output changes from a solid line to a broken line as shown by an arrow A1, as shown in FIG. Shift to the left side, that is, the short wavelength side.
- the green light output moves to point P2 and rises, as shown by arrow A2.
- the environmental temperature during operation can be monitored.
- the phase matching wavelength of the wavelength conversion element 27 is in the standby position, if the green light output increases, the environmental temperature decreases, and if the green light output decreases, the environmental temperature increases. Therefore, the temperature of the fiber grating 25 can be controlled based on this output value.
- FIG. 20 is a flowchart for explaining a temperature control process of the fiber grating 25 by the determination circuit 72 shown in FIG.
- the determination circuit 72 obtains the output value of green light determined according to the light amount control signal LC from the current output value table 75, and the output value of the wavelength conversion element 27 and the obtained output value.
- the current value of the excitation laser current source 31 is controlled via the D / A change 73.
- step S2 the determination circuit 72 confirms that the current value of the excitation laser current source 31 is within a predetermined usable range, and outputs an output detection signal output from the light receiving element 29.
- the force also determines whether or not the output value of the green light has fluctuated. If the output value of the green light has changed and is falling, the process proceeds to step S3, and if it is rising, the process is stepped. Transfer processing to S5. On the other hand, when the output value of the green light has not changed, the processing after step S1 is repeated, and the green light corresponding to the light quantity control signal LC is output.
- step S3 the determination circuit 72 instructs the PWM signal generator 74 to increase the average current value flowing through the Peltier element 66, and generates the PWM signal.
- the vessel 74 cools the fiber grating 25 by lowering the temperature of the Peltier element 66.
- step S4 the determination circuit 72 checks that the current value of the excitation laser current source 31 is within a predetermined usable range, and the output detection signal power output from the light receiving element 29 is also green light. Check the output value of.
- step S5 when the output value of the green light is increasing, in step S5, the determination circuit 72 instructs the PWM signal generator 74 to decrease the average current value flowing through the Peltier element 66, and the PWM The signal generator 74 increases the temperature of the Peltier element 66 and heats the fiber darling 25.
- step S5 the determination circuit 72 checks that the current value of the excitation laser current source 31 is within a predetermined usable range, and the output detection signal power output from the light receiving element 29 is also green. Check the light output value.
- step S4 or S5 the determination circuit 72 compares the current value of the excitation laser current source 31 with the initial current value with respect to the output value of the green light after the above process is executed. If the difference between the two is within the predetermined range, the processing after step S1 is continued. If the difference between the two is outside the predetermined range, the processing after steps S3 and S5 is continued. .
- the fiber grating 25 can be heated according to the output value of the green light, so the shift amount due to the temperature rise of the phase matching wavelength and the wavelength of the fundamental wave can be increased.
- the amount of shift can be matched, and W-class high-power green light can be stably obtained from the wavelength conversion element 27.
- the temperature of the wavelength conversion element 27 is controlled by the Peltier element 67.
- the temperature increase of the wavelength conversion element 27 is greater on the output side of the wavelength converted light than on the input side of the fundamental wave. Therefore, the temperature of the input side portion and the output side portion of the wavelength conversion element 27 may be individually controlled by using a plurality of Peltier elements instead of the Peltier element 67 as described below.
- FIG. 21 is a configuration diagram in the case where the temperature control of the wavelength conversion element is performed by a plurality of Peltier elements. As shown in FIG. 21, a plurality of Peltiers are arranged in the light propagation direction of the wavelength conversion element 27. Elements 110 and 111 are arranged. A periodic domain-inverted region 102 is formed in the wavelength conversion element 27, and the domain-inverted region 102 was produced by an electric field application method.
- the substrate of the wavelength conversion element 27 has a thickness of lmm, and the domain-inverted region 102 is formed along the Y-axis of the substrate crystal.
- the domain-inverted region 102 is formed by directing force from the + Z plane to the ⁇ Z plane side of the substrate.
- the polarization inversion period ⁇ is formed by 6.
- 4nm light (Nd: YAG laser) can be converted into green light with a wavelength of 532nm.
- Two copper plates 109 are attached to the surface of the wavelength conversion element 27 via a heat dissipation agent 108 for heat dissipation, and further, a Peltier element 110 is attached to the two copper plates 109 via the heat dissipation agent 108. 1 11 is pasted.
- Two Peltier elements 110 and 111 are used as temperature control elements for controlling the temperature of the wavelength conversion element 27. The temperature can be controlled.
- FIG. 22 is a diagram showing the relationship between the distance from the incident surface 106 of the wavelength conversion element 27 and the SHG output.
- the wavelength conversion element 27 when converting a fundamental wave with a wavelength of 1064nm to SHG (harmonic) with a wavelength of 532nm, the input of the fundamental wave is 10W, the condensed diameter of the fundamental wave is ⁇ 33 / zm, and the fundamental wave beam Assuming that the quality is almost ideal Gaussian distribution, when the length of the wavelength conversion element 27 is 10 mm, the SHG intensity is 1.5 W at a position approximately 7 mm from the incident surface 106 of the wavelength conversion element 27. Over. The value of P (poor) at the SHG wavelength of 532 nm is about 1.5 W.
- the wavelength conversion is performed by installing the Peltier element 111 that performs temperature control most recently in the range of 3 mm from the emission surface near the emission part of the element length and controlling the temperature.
- the conversion efficiency of element 27 can be greatly increased.
- FIG. 23 shows the result of measuring the output characteristics of green light by controlling the temperature of the wavelength conversion element 27 having the above configuration with the Peltier elements 110 and 111.
- the conversion efficiency when the SHG output is 1.5 W or less is 3% ZW. Even if the SHG output is 1.5 W or more, the square characteristics are degraded, the output is unstable, and The conversion efficiency did not decrease, and a high-quality beam profile could be obtained with a stable output.
- the temperature rise is remarkable in order to avoid the temperature distribution generated in the propagation direction.
- Two or more Peltier elements arranged near the exit surface 107 where the SHG power deteriorates may be arranged. As shown in FIG. 24, a plurality of Peltier elements 211, 212 are arranged near the emission surface 107 of the wavelength conversion element 27 where heat generation is concentrated so that the element temperature is constant according to the temperature distribution in the light propagation direction. Place.
- the arrangement method of Peltier elements is not limited to these arrangement methods as long as the temperature distribution is suppressed! /.
- the length for individually controlling the vicinity of the emission surface 107 with a Peltier element is desirably 1Z2 or less of the full length.
- the conversion efficiency is improved when the focusing characteristics of the fundamental wave are set so that the focal point is at the center of the crystal and the beam diameter of the fundamental wave is maximized at both ends of the crystal. Maximum. At this time, the SHG intensity in the element is approximately three times higher at the exit surface than the power at the center of the element. As a result of the experiment, it was found that when the maximum output exceeds 3 times P (poor) where the conversion efficiency deteriorates, crystal breakage occurs due to light absorption.
- the length of temperature control individually in the vicinity of the emission surface 107 is set to be more than half of the element length, it is not possible to increase the output light. Therefore, it is preferable to make the length less than half of the element length. .
- the temperature adjustment method in this example is not particularly limited to the above example, and the SHG output near the emission surface of the wavelength conversion element and the heat dissipation characteristics of the portion where the SHG power density is maximized should be improved. It is also possible to suppress the element temperature distribution by heating the part so that SHG power degradation does not occur so that the SHG output and SHG power density in the vicinity of the output face of the wavelength conversion element will be the highest. Even if you do it.
- the output of the wavelength converter is the force described with the green laser of 530 nm.
- the wavelength of the output of the wavelength converter is an ultraviolet light including a visible light region of 400 to 900 nm. If the region force is up to the infrared region and the wavelength of the fiber laser is 800 to 180 Onm, the same effects as described in the above embodiments can be obtained. Further, the above embodiments can be arbitrarily combined, and in that case, the effects of the respective configurations can be obtained.
- the wavelength conversion device includes a laser active substance and includes two fiber gratings.
- a laser resonator that is configured by optically connecting a fiber in which a ring is formed and a laser light source that makes excitation light incident on the fiber, and converts a fundamental wave of the laser emitted from the laser resonator into a harmonic.
- a wavelength conversion element, wherein the fiber grating is
- the first fiber grating on the laser light source side and the second fiber grating on the wavelength conversion element side, and the temperature of the second fiber grating is the wavelength of the harmonics output from the wavelength conversion element force. It is adjusted according to the output.
- the temperature of the second fiber grating on the wavelength conversion element side is adjusted according to the output of the harmonics output from the wavelength conversion element force.
- the wavelength of the fundamental wave can be greatly shifted by greatly increasing the temperature of the fiber grating.
- the wavelength of the fundamental wave can be shifted so as not to deviate from the wavelength that can be converted by the wavelength conversion element, so that W-class high-power wavelength conversion light can be stably obtained from the wavelength conversion element. .
- the fiber preferably absorbs a part of the output of the fundamental wave or the excitation light by doping a rare earth element to a set concentration.
- the fiber absorbs a part of the output of the fundamental wave or excitation light propagating inside by doping the rare earth element to the set concentration. This absorbed light turns into heat and heats the fiber grating, which selects the fundamental wavelength.
- the fiber grating is heated and the temperature rises, and the spacing between the gratings increases due to thermal expansion. As a result, the wavelength of the fundamental wave is greatly shifted to the longer wavelength side.
- the output of the fundamental wave is about 10 W, so the internal temperature of the wavelength conversion element rises and the wavelength that can be converted is large. Shift to long wavelength side.
- the wavelength of the fundamental wave does not shift slightly toward the longer wavelength side.
- the wavelength of the fundamental wave is large and has a long wavelength. Shift to the side.
- the wavelength of the fundamental wave incident on the wavelength conversion element and the wavelength that can be converted by the wavelength conversion element can be followed and shifted to the longer wavelength side. Therefore, in the above wavelength converter, the wavelength-converted output light Can be stably obtained up to w-class high output.
- the rare earth element is at least one selected from Nd, Er, Dy, Pr, Tb, and Eu force.
- the rare earth element may be doped at a concentration of 1000 to 3000 ppm. preferable.
- the fiber grating can be further effectively heated by doping the selected rare earth element at a set concentration.
- the rare earth element is preferably at least one selected from Yb, Ce, Tm, Ho, Gd, Y and La.
- the rare earth element is doped at a concentration of 20000 to 30000 ppm. It is preferable.
- the fiber grating can be effectively heated by doping the selected rare earth element at a set concentration.
- the rare earth element is preferably doped in the cladding portion of the fiber.
- the fiber bag rating can be heated more effectively by doping rare earth elements in the cladding of the fiber.
- the rare earth element is preferably doped in the core of the fiber.
- the fiber grating can be heated more effectively by doping the core portion of the fiber with a rare earth element.
- the fiber is formed by optically connecting a first fiber in which the first fiber grating is formed and a second fiber in which the second fiber grating is formed. I prefer to be structured.
- the fiber in which the second fiber grating for selecting the fundamental wave is formed can be manufactured as the second fiber separately from the first fiber
- the second fiber is a fiber grating. It can be fabricated with a configuration in which a part of the output of the fundamental wave or excitation light is absorbed more efficiently by doping with a rare earth element in the vicinity.
- the first fiber includes a laser active material and has a configuration that converts the excitation light into the fundamental wave more efficiently.
- the fiber includes a first fiber on which the first fiber grating is formed, a second fiber, and a third fiber on which the second fiber grating is formed. It is preferable that the first fiber and the third fiber are optically connected to both ends of the fiber.
- the fiber in which the second fiber grating for selecting the fundamental wave is formed can be manufactured as the third fiber separately from the first fiber
- the third fiber is a fiber grating. It can be fabricated with a configuration in which a part of the output of the fundamental wave or excitation light is absorbed more efficiently by doping with a rare earth element in the vicinity.
- the first fiber can also be configured to contain a laser active substance and to convert the excitation light into the fundamental wave more efficiently.
- the second fiber absorbs as little of the fundamental wave or pump light output as possible to reduce the fundamental wave or pump light loss in the second fiber. .
- the fiber has a double-clad structural force.
- At least one clad portion of the double clad structure absorbs a part of the fundamental wave and the excitation light, and the fiber grating can be heated more effectively.
- At least one clad portion of the double clad structure is doped with the rare earth element! /.
- a rare earth element is doped in at least one of the clad portions of the double clad structure to absorb a part of the fundamental wave and the excitation light, thereby heating the fiber grating more effectively. Can do.
- the fiber grating It is preferable to further include a heating unit for heating the group.
- the fiber dulling can be more effectively heated by the heating unit that absorbs part of the output of the fundamental wave or the excitation light.
- the heating unit is a re-coating layer provided in a region where the second fiber grating is formed.
- the material of the re-coating layer is preferably a flame retardant material.
- the fiber can ensure higher safety.
- the refractive index of the material of the recoating layer is preferably 1.37 to L43.
- the heating unit includes a temperature control member for controlling the temperature of the wavelength conversion element, and a holding base for holding the second fiber grating and the wavelength conversion element, and the temperature control member force generation It is preferable that the second fiber grating is heated by the conducted heat being conducted to the second fiber darling via the holding table.
- the heat generated by the temperature control of the wavelength conversion element is conducted to the fiber grating through the holding base, and therefore the fiber grating can be heated more effectively.
- the heating unit absorbs the fundamental wave or the leakage light of the excitation light and generates heat, and has a material force having a thermal expansion coefficient larger than that of the fiber, and maintains the second fiber grating. It is preferable that the holding member absorbs a tensile stress in the second fiber grating by thermal expansion due to its own heat generation.
- the holding member is heated and expanded, whereby the fiber grating is stretched and the grating interval is mechanically expanded. Therefore, the wavelength of the fundamental wave can be further shifted to the longer wavelength side. As a result, even if the fundamental wave has a high output, the fundamental wave The length and the wavelength that can be converted by the wavelength conversion element shift in substantially the same manner, and the laser output after wavelength conversion can be controlled more effectively to a high output of the w class.
- the wavelength conversion device includes a detection unit that detects a part of the output of the fundamental wave, and a control that controls an output of the harmonics emitted from the wavelength conversion element force based on a detection value by the detection unit. It is preferable to further comprise means.
- control means controls the temperature of at least one of the fiber bag rating and the wavelength conversion element based on data stored in advance in a table format.
- control means performs temperature control of at least one of the fiber grating and the wavelength conversion element based on a phase matching wavelength change amount of the wavelength conversion element with respect to an output of the fundamental wave.
- phase matching wavelength variation of the wavelength conversion element with respect to the fundamental wave output can be stored in advance as table format data and used at any time for temperature control.
- the laser output can be controlled to a high output of class W with higher accuracy.
- control means performs temperature control of at least one of the fiber grating and the wavelength conversion element based on a reflected wavelength change amount of the fiber grating with respect to the output of the fundamental wave.
- the amount of change in the reflected wavelength of the fiber grating with respect to the fundamental wave output that is, the amount of change in the wavelength of the fundamental wave incident on the wavelength conversion element is stored in advance as table format data for temperature control. Since it can be used from time to time, after wavelength conversion The laser output can be controlled with higher accuracy up to the w-class high output.
- the detecting means preferably includes a light receiving element that receives the branched light of the fundamental wave from the fiber.
- the laser output after wavelength conversion can be controlled to a high W-class output with higher accuracy.
- the detection means receives the leaked light of the fundamental wave from the fiber grating.
- the output of the fundamental wave can be grasped quantitatively and accurately, so that the laser output after wavelength conversion can be controlled with high accuracy to a high output of class W, and the fundamental wave Since leakage light is received, unnecessary loss of the fundamental wave can be suppressed.
- the wavelength conversion device controls a temperature of the second fiber grating based on a detection unit that detects a part of the harmonic output and a detected value of the harmonic output by the detection unit. It is preferable to further comprise a control means.
- the fiber grating can be heated according to the output value of the harmonics, the shift amount due to the temperature rise of the phase matching wavelength and the shift amount of the fundamental wavelength can be matched, It is possible to control the laser output after wavelength conversion to a high W-class output with higher accuracy.
- the wavelength of the harmonic is preferably 510 to 550 nm, and the output of the harmonic is preferably 1 W or more.
- the output of green light after wavelength conversion is the same as that of class W when there is no output decrease due to absorption of ultraviolet light-induced green light. It can be increased to high output.
- the wavelength of the harmonic is preferably 440 to 490 nm, and the output of the harmonic is preferably 0.1 W or more.
- w-class high-output wavelength-converted light can be stably obtained from the wavelength conversion element, so that it is useful as a wavelength converter that serves as a high-output visible light source such as a large display or a high-intensity display. is there.
Landscapes
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Nonlinear Science (AREA)
- Electromagnetism (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Lasers (AREA)
- Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2007542783A JP5484672B2 (ja) | 2005-11-04 | 2006-11-01 | 波長変換装置 |
US12/092,694 US7791790B2 (en) | 2005-11-04 | 2006-11-01 | Wavelength converter |
CN2006800395512A CN101297237B (zh) | 2005-11-04 | 2006-11-01 | 波长变换装置 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2005-320397 | 2005-11-04 | ||
JP2005320397 | 2005-11-04 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2007052702A1 true WO2007052702A1 (ja) | 2007-05-10 |
Family
ID=38005855
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2006/321862 WO2007052702A1 (ja) | 2005-11-04 | 2006-11-01 | 波長変換装置 |
Country Status (4)
Country | Link |
---|---|
US (1) | US7791790B2 (ja) |
JP (1) | JP5484672B2 (ja) |
CN (1) | CN101297237B (ja) |
WO (1) | WO2007052702A1 (ja) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2009015040A (ja) * | 2007-07-05 | 2009-01-22 | Cyber Laser Kk | レーザ光第2高調波発生装置 |
JP2009194371A (ja) * | 2008-01-16 | 2009-08-27 | Panasonic Corp | 波長変換レーザ光源、これを備えた2次元画像表示装置およびレーザ光源装置 |
JP2009258431A (ja) * | 2008-04-17 | 2009-11-05 | Yokogawa Electric Corp | 波長可変光源 |
JP2012191121A (ja) * | 2011-03-14 | 2012-10-04 | Seiko Epson Corp | 原子発振器用の光学モジュールおよび原子発振器 |
US9054638B2 (en) | 2010-07-14 | 2015-06-09 | Seiko Epson Corporation | Optical module and atomic oscillator |
JP2017198814A (ja) * | 2016-04-27 | 2017-11-02 | レーザーテック株式会社 | 光源装置、検査装置及び光源装置の制御方法 |
KR101975793B1 (ko) * | 2017-11-28 | 2019-05-07 | 김정수 | 파장 가변필터 |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPWO2007066747A1 (ja) * | 2005-12-09 | 2009-05-21 | パナソニック株式会社 | ファイバーレーザ |
US7859744B2 (en) * | 2007-07-27 | 2010-12-28 | Magiq Technologies, Inc. | Tunable compact entangled-photon source and QKD system using same |
CN102414943B (zh) * | 2010-03-02 | 2014-05-07 | 松下电器产业株式会社 | 波长转换装置及利用该波长转换装置的图像显示装置 |
JP7069037B2 (ja) * | 2016-04-27 | 2022-05-17 | ルミレッズ ホールディング ベーフェー | レーザベース光源 |
CN106058622A (zh) * | 2016-07-08 | 2016-10-26 | 上海大学 | 基于铕离子掺杂荧光光纤的光纤有源器件 |
JP2018018720A (ja) * | 2016-07-28 | 2018-02-01 | パナソニックIpマネジメント株式会社 | 発光装置、および、発光装置の点検方法 |
CN108865108B (zh) * | 2018-08-03 | 2021-04-16 | 广东工业大学 | 一种铌酸盐变色材料及其制备方法 |
US11880062B2 (en) * | 2018-11-30 | 2024-01-23 | The Board Of Trustees Of The University Of Illinois | Microheater comprising a rare earth-doped optical fiber |
CN111929248A (zh) * | 2020-08-26 | 2020-11-13 | 重庆渝微电子技术研究院有限公司 | 半导体冷热台 |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH1138460A (ja) * | 1997-07-24 | 1999-02-12 | Mitsubishi Cable Ind Ltd | レーザ装置 |
US6510167B1 (en) * | 1999-09-22 | 2003-01-21 | Science & Technology Corporation @Unm | Method for actively modelocking an all-fiber laser |
JP2004020571A (ja) * | 2002-06-12 | 2004-01-22 | Mitsubishi Cable Ind Ltd | 波長変換装置 |
JP2005181509A (ja) * | 2003-12-17 | 2005-07-07 | Shimadzu Corp | 波長変換レーザ装置 |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5682398A (en) * | 1996-05-03 | 1997-10-28 | Eastman Kodak Company | Frequency conversion laser devices |
US5982791A (en) * | 1998-01-14 | 1999-11-09 | Hewlett-Packard Company | Wavelength tracking in adjustable optical systems |
JP2001183713A (ja) * | 1999-12-22 | 2001-07-06 | Ngk Insulators Ltd | 第二高調波発生装置 |
US6594288B1 (en) * | 2000-11-06 | 2003-07-15 | Cidra Corporation | Tunable raman laser and amplifier |
US6768577B2 (en) * | 2002-03-15 | 2004-07-27 | Fitel Usa Corp. | Tunable multimode laser diode module, tunable multimode wavelength division multiplex raman pump, and amplifier, and a system, method, and computer program product for controlling tunable multimode laser diodes, raman pumps, and raman amplifiers |
JP4258206B2 (ja) | 2002-11-13 | 2009-04-30 | 株式会社島津製作所 | 波長変換レーザ装置 |
US7142572B2 (en) * | 2002-11-13 | 2006-11-28 | Shimadzu Corporation | Wavelength conversion laser apparatus with tunable fiber Bragg grating |
JP4111075B2 (ja) | 2003-06-18 | 2008-07-02 | 株式会社島津製作所 | 波長変換レーザ装置 |
US7103075B2 (en) * | 2003-06-18 | 2006-09-05 | Shimadzu Corporation | Solid laser apparatus |
JP2005115192A (ja) | 2003-10-10 | 2005-04-28 | Shinko Densen Kk | ファイバーグレーティングの温度補償 |
-
2006
- 2006-11-01 JP JP2007542783A patent/JP5484672B2/ja not_active Expired - Fee Related
- 2006-11-01 WO PCT/JP2006/321862 patent/WO2007052702A1/ja active Application Filing
- 2006-11-01 US US12/092,694 patent/US7791790B2/en not_active Expired - Fee Related
- 2006-11-01 CN CN2006800395512A patent/CN101297237B/zh not_active Expired - Fee Related
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH1138460A (ja) * | 1997-07-24 | 1999-02-12 | Mitsubishi Cable Ind Ltd | レーザ装置 |
US6510167B1 (en) * | 1999-09-22 | 2003-01-21 | Science & Technology Corporation @Unm | Method for actively modelocking an all-fiber laser |
JP2004020571A (ja) * | 2002-06-12 | 2004-01-22 | Mitsubishi Cable Ind Ltd | 波長変換装置 |
JP2005181509A (ja) * | 2003-12-17 | 2005-07-07 | Shimadzu Corp | 波長変換レーザ装置 |
Non-Patent Citations (2)
Title |
---|
BOUCHIER A. ET AL.: "Single-mode Yb-doped fiber laser at 980 nm for efficient frequency-doubling", LASERS AND ELECTRO-OPTICS, 2005 (CLEO). CONFERENCE, May 2005 (2005-05-01), pages 1995 - 1997, XP010877033 * |
FURUYA H. ET AL.: "Shuki Bunkyoku Hanten MgO:LiNb03 o Mochiita Bulk-gata SHG Device ni yoru 3WCW Ryokushokuko Hassei", DAI 52 KAI OYO BUTSURIGAKU KANKEI RENGO KOENKAI KOEN YOKOSHU, no. 3, March 2005 (2005-03-01), pages 1331, XP002996870 * |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2009015040A (ja) * | 2007-07-05 | 2009-01-22 | Cyber Laser Kk | レーザ光第2高調波発生装置 |
JP2009194371A (ja) * | 2008-01-16 | 2009-08-27 | Panasonic Corp | 波長変換レーザ光源、これを備えた2次元画像表示装置およびレーザ光源装置 |
JP2009258431A (ja) * | 2008-04-17 | 2009-11-05 | Yokogawa Electric Corp | 波長可変光源 |
US9054638B2 (en) | 2010-07-14 | 2015-06-09 | Seiko Epson Corporation | Optical module and atomic oscillator |
JP2012191121A (ja) * | 2011-03-14 | 2012-10-04 | Seiko Epson Corp | 原子発振器用の光学モジュールおよび原子発振器 |
JP2017198814A (ja) * | 2016-04-27 | 2017-11-02 | レーザーテック株式会社 | 光源装置、検査装置及び光源装置の制御方法 |
KR101975793B1 (ko) * | 2017-11-28 | 2019-05-07 | 김정수 | 파장 가변필터 |
Also Published As
Publication number | Publication date |
---|---|
US7791790B2 (en) | 2010-09-07 |
JP5484672B2 (ja) | 2014-05-07 |
US20090251766A1 (en) | 2009-10-08 |
CN101297237A (zh) | 2008-10-29 |
CN101297237B (zh) | 2012-03-21 |
JPWO2007052702A1 (ja) | 2009-04-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5484672B2 (ja) | 波長変換装置 | |
JP5180086B2 (ja) | 波長変換装置および画像表示装置 | |
JP5259716B2 (ja) | 波長変換レーザ光源、これを備えたプロジェクションディスプレイ装置、液晶ディスプレイ装置及びレーザ光源 | |
JP4855401B2 (ja) | 波長変換素子、レーザ光源装置、2次元画像表示装置及びレーザ加工装置 | |
WO2004025363A1 (ja) | 波長変換モジュール | |
US20110255562A1 (en) | Plane waveguide type laser and display device | |
WO2011132414A1 (ja) | 波長変換レーザ光源及び画像表示装置 | |
WO2012066596A1 (ja) | レーザ光源、レーザ加工装置、および半導体の加工方法 | |
JPWO2009031278A1 (ja) | 波長変換装置、画像表示装置及び加工装置 | |
JP5064777B2 (ja) | レーザ装置 | |
WO2007097177A1 (ja) | 波長変換装置及び画像表示装置 | |
JP3509598B2 (ja) | 半導体レーザ励起固体レーザ装置 | |
JP2007095995A (ja) | レーザ装置 | |
US20070041420A1 (en) | Solid-state laser device | |
CN116348814A (zh) | 紫外激光系统、设备和方法 | |
CN101383477A (zh) | 激光二次谐波发生装置 | |
JP2004157217A (ja) | 波長変換レーザ光源 | |
WO2007116563A1 (ja) | 光源 | |
JPWO2007013134A1 (ja) | 半導体レーザ励起固体レーザ装置 | |
JP4600129B2 (ja) | 固体レーザ装置 | |
Matsuura et al. | Development of a low-noise yellow-green laser using a Yb-doped double-clad fiber laser and a periodically poled LiNbO3 waveguide crystal | |
Kharlamov et al. | CW 488 nm laser with external-cavity frequency doubling of a multi-longitudinal-mode semiconductor source | |
JP2011223024A (ja) | 半導体レーザ励起固体レーザ装置 | |
JP2008216531A (ja) | レーザ装置 | |
JP2003315859A (ja) | 波長変換レーザ装置 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 200680039551.2 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
ENP | Entry into the national phase |
Ref document number: 2007542783 Country of ref document: JP Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 12092694 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 06822791 Country of ref document: EP Kind code of ref document: A1 |