CN210007099U

CN210007099U - Dye laser device with Nile red organic solvents as gain media

Info

Publication number: CN210007099U
Application number: CN201920308949.6U
Authority: CN
Inventors: 方昱玮; 程军杰; 王声波; 王贯; 董天浩; 顾春; 许立新
Original assignee: University of Science and Technology of China USTC
Current assignee: University of Science and Technology of China USTC
Priority date: 2019-03-12
Filing date: 2019-03-12
Publication date: 2020-01-31
Anticipated expiration: 2029-03-12

Abstract

The utility model provides a dye laser device of kinds of nile red organic solvents as gain medium, this dye laser device include the Nd of the double frequency of as the pumping source YAG laser instrument, optical system and dyestuff laser cavity, dyestuff laser cavity is including the quartz cuvette that is equipped with nile red organic solution the utility model discloses a nile red is as laser gain medium, utilizes the solvation color development characteristic of nile red, and fluorescence/laser intensity in different organic solvents is relevant with the polarity of central wavelength and solvent promptly, obtains 78nm tuning range's laser output through changing system polarity to and the result of dual wavelength "proportion laser".

Description

Dye laser device with Nile red organic solvents as gain media

Technical Field

The utility model relates to an kinds of dye laser, specifically be kinds of nile red organic solvent as the dye laser device of gain medium.

Background

Since ruby lasers appeared in the world in 1960, laser technology has been developed rapidly for over 50 years, lasers have the characteristics of good monochromaticity, strong directivity, high brightness and the like, thousands of laser working substances are found, the wavelength range is from soft X rays to far infrared rays, so that the application range is , and the laser working substances are combined with multiple subjects to form multiple application technical fields, such as laser processing technology, laser detection and measurement technology, laser spectrum technology, nonlinear optics, laser chemistry, laser radar, laser weapons, spectrum detection technology of atmospheric environment and the like.

Since the appearance of the laser in 1960, the tunable function was which was the important content of laser research, the core device of the tunable laser was a tunable laser medium with a broadband energy level structure, among many lasers, the dye laser became the focus research object of researchers for researching tunable lasers, the dye laser was a laser using an organic dye dissolved in constant solvent (methanol, ethanol, water, etc.) as a gain medium, the organic dye laser was first researched in 1964 by Stockman, the laser output was first obtained by using ruby laser to pump cyanine dyes from Sorokin and Lankard in 1966, the dye laser began to be rapidly developed, and reflectors of the resonant cavity were replaced by diffraction gratings from sorrel and faand in 1967, not only the output spectrum was compressed, but also a continuous tunable range of tens of nanometers was obtained, and a new method is provided for obtaining the tunable output of the dye laser.

The dye laser has the characteristics of wide output spectral line range, high power, easily controlled absorption and gain, and the like, wherein the most important point is that the output laser wavelength is continuously adjustable in a wide range.

SUMMERY OF THE UTILITY MODEL

The utility model aims at adopting novel laser dyes-nile red, and designing dye laser systems using nile red organic solvent as gain medium.

The utility model adopts the technical scheme that kinds of nile red organic solvent are as the dye laser device of gain medium, including laser pumping source, optical system and laser dye resonant cavity, wherein laser pumping source 1 is Nd: YAG solid laser, the light beam that the pumping source sent obtains the frequency doubling output light through frequency doubling optical crystal 2, adjust output energy jointly by half-wave plate 3 and polaroid 4, after change the light path direction through total reflection mirror 5 and second total reflection mirror 6, through beam splitting mirror 7, partial pump light is through third total reflection mirror 15 access energy meter 16 monitoring pump energy, part direct pumping dye laser gain system, pump light enters gain system after focusing lens 8 and aperture diaphragm 9, gain system includes plane dichroic mirror 10, the quartz cuvette 11 of the different organic solvents of nile red is equipped with, reflection formula blazed grating 12 and tuning total reflection mirror 13, plane dichroic mirror 10 is located aperture diaphragm 9 after 10mm, quartz cuvette 11 of the organic solvent of nile red is located behind the plane dichroic mirror 10mm, reflection formula blazed grating 12 and tuning total reflection formula blazed mirror 13, the incident light grating 12 is a distance on the surface of the quartz cuvette 11, the quartz cuvette 12 is 20mm, and the total reflection formula blazed grating 13 is carried out parallel reflection formula laser spectrometer of incident light, the incident light is carried out on the right side and is 20mm of the parallel reflection formula of the grating 13 grating.

Wherein, the Nile red used in the experiment is fluorescent dyes, the molecular formula is C20H18N2O2, the used organic solvents are respectively ethanol, acetone, ether and toluene, the content GC of the ethanol, the acetone, the ether and the toluene solvent is more than or equal to 99.5%, the concentration value of the Nile red in a pure ethanol solution is 60 mu g/mL, and the concentration value in a pure acetone solution, a pure toluene solution and a pure ether solution is 50 mu g/mL.

YAG solid laser, and output laser wavelength of 1064 nm. YAG solid laser is produced with potassium titanyl phosphate (KTP) crystal as frequency doubling crystal.

The th total reflection mirror 5, the second total reflection mirror 6 and the third total reflection mirror 15 are surface-coated 1064nm/532nm dichroic mirrors, the reflectivity R is greater than 99.5% around 532nm, the splitting ratio of the beam splitter 7 is 1:9, wherein 90% of the energy of the pumping light is reflected by the beam splitter 7 and the third total reflection mirror 15 and then is connected to an energy meter 16 to monitor the pumping energy, in addition, 10% of the energy of the pumping light penetrates through the beam splitter 7 to be used as a direct pumping source of the dye laser gain system, and the pumping laser penetrating through the beam splitter 7 enters the dye laser resonant cavity after passing through a focusing lens 8 with the focal length of 17cm and a small-hole diaphragm 9 with the light-transmitting caliber of 5 mm.

The laser dye resonant cavity comprises a plane dichroic mirror 10, a quartz cuvette 11, a reflective blazed grating 12 and a tuning total reflection mirror, the total length of the resonant cavity is about 5cm, the plane dichroic mirror 10 is a plane dichroic mirror, and the transmittance T of the laser dye resonant cavity at 532nm is more than 95% and the reflectance R of the laser dye resonant cavity within the range of 560-700 nm is more than 95% through film coating. The quartz cuvette 11 is used for containing different organic solutions of Nile red, the optical path is 5mm, and the transmissivity of two optical surfaces is over 99.5% within the range of 400-700 nm. The pumping light passes through the plane dichroic mirror 10 and the quartz cuvette 11 and is glancing-projected into the reflective blazed grating 12. The reflection type blazed grating 12(1200 lines/mm) is a common scribed grating with the blazed wavelength of 500nm, the size of the common scribed grating is 10cm x 10cm, and the tuning total reflection mirror 13 is an aluminized broadband reflection mirror. The stronger 1 st order diffraction light is fed back to the resonant cavity through the tuning total reflection mirror 13 to continue oscillation, and the dye laser transmitted along the axial direction is finally output along the 0 th order direction of the grating diffraction. The angle of grazing incidence of the grating is fixed, and tunable output of the dye laser can be realized by rotating the tuning total reflection mirror 13.

Wherein, the tuning total reflection mirror is kept not to rotate, pure ether and pure ethanol solvent are prepared into mixed solvent according to the content ratio of 10:0 to 0:10 by utilizing the solvatochromic characteristic of Nile red, and the Nile red is respectively dissolved in the mixed solvent at the concentration of 50 mug/mL, thereby realizing the tunable output of dye laser.

The method for realizing proportional laser dual-wavelength output comprises the steps of adopting double-layer serially-connected quartz cuvettes, wherein a front cavity is filled with 100 mu G/mL rhodamine 6G ethanol solution, a rear cavity is filled with Nile red ethanol solution, the concentrations of the two solutions are respectively configured to be 120 mu G/mL, 100 mu G/mL, 80 mu G/mL, 60 mu G/mL, 40 mu G/mL, 20 mu G/mL and 10 mu G/mL, groups of dual-wavelength laser output is obtained, the peak wavelength of output laser of the rhodamine 6G dye is kept unchanged, the output laser wavelength and the relative intensity of the Nile red dye are continuously changed along with the change of the concentrations, and groups of proportional laser output are obtained.

The utility model has the advantages of it is following:

1. the method utilizes the solvation color development characteristic of Nile red, changes the polarity of the environment by mixing organic solvents, and obtains the tuning of the output laser of the Nile red.

2. On the basis of solvent polarity tuning, a grating is added for compressing spectral width and outputting tuning, the tuning range of the Nile red organic solution is expanded, and the whole tuning range reaches nearly 80 nm.

3. Two quartz cuvettes are connected in series, the rhodamine ethanol solution and the nile red ethanol solution are pumped simultaneously, groups of proportional laser output are obtained by continuously changing the concentration of the nile red in the ethanol solution, and the method can be used for calibrating the tiny amount, detecting the concentration of the solution, expanding the tuning range of a dye laser and the like.

4. The whole structure is simple, the operation is easy, and the cost is lower.

Drawings

Fig. 1 is an optical diagram for realizing grating tuning and solvent polarity tuning in the present invention.

FIG. 2 shows the fluorescence output versus laser spectrum of the Nile Red ethanol solution of example 1.

FIG. 3 is the output energy and half-height width of the Nile Red ethanol solution of example 1 as a function of pump energy.

FIG. 4, FIG. 5 and FIG. 6 are the fluorescence output and laser spectrum of Nile Red acetone solution, Nile Red toluene solution and Nile Red Ether solution in examples 2, 3 and 4, respectively.

FIG. 7 is a laser tuning output spectrum obtained by changing the solvent ratio of Nile Red in the mixed solvent of ether and ethanol in example 5.

FIG. 8 is a graph of the total laser tuning output spectrum of Nile Red in Ether-EtOH mixed solution obtained by rotating and tuning the holomirror based on the polar tuning in example 5.

FIG. 9 is a light path diagram of a serial pumped rhodamine 6G/Nile Red ethanol solution as in example 6.

FIG. 10 is a plot of the "proportional laser" output spectra of the serially pumped rhodamine 6G/Nile Red ethanol solution of example 6.

FIG. 11 is a comparison of the tuning range of Nile Red laser at different concentrations obtained for the mixed solution system of rhodamine 6G/Nile Red ethanol of example 6, versus the tuning range of laser output at different concentrations in the single Nile Red/ethanol solution.

Detailed Description

The following describes in detail specific embodiments of the present invention with reference to the accompanying drawings.

In an embodiment 1, fig. 1 shows an optical path diagram for realizing grating tuning and solvent polarity tuning in the present invention, a whole dye laser device includes a laser pumping source, an optical system and a dye laser resonant cavity, the laser pumping source 1 is an Nd: YAG solid laser, and outputs frequency-doubled by a KTP crystal 2, the optical system includes an energy adjusting system composed of a half-wave plate 3 and a polarizing plate 4, a th total reflection mirror 5, a second total reflection mirror 6, a third total reflection mirror 15, a beam splitter 7, a focusing lens 8 and a small aperture diaphragm 9, a th total reflection mirror 5, the second total reflection mirror 6 and the third total reflection mirror 15 are 1064nm/532nm dichroic mirrors with surface-coated films, the reflectivity of the beam splitter 7 is greater than 99.5%, the beam splitting ratio of the beam 7 is 1:9, wherein, pumping energy is monitored by an energy meter 16, pumping energy is transmitted through the beam splitter 7 and the third total reflection mirror 15 after being reflected by the beam splitter, and then transmitted through a linear reflection mirror 11 cm, the linear reflection mirror is greater than 10mm, the total reflection transmittance of a quartz reflection film is greater than 10mm, the linear reflection spectrum of a grating reflection film, the reflection film is greater than 10.5 mm, the reflection spectrum of a 10.5 mm, the transmittance of a 10 g reflective film is greater than 10mm, the spectrum reflection film is greater than 10.5 mm, the spectrum reflection film of a 10mm, the spectrum reflection film is contained in a 10.5 mm, the spectrum reflection film in a spectrum reflection film of a spectrum of.

As shown in fig. 2 and 3, the tuning total reflection mirror is kept not to rotate, and the fluorescence and laser spectrum of nile red in an ethanol solution, and the output energy and the variation curve of the full width at half maximum of the spectrum with the pumping energy are obtained by continuously increasing the pumping energy. Curve 1 in FIG. 2 represents the ethanol solution of example 1The fluorescence spectrum of the solution below the pumping threshold, and curve 2 represents the laser spectrum of the nile red/ethanol solution obtained after the pumping energy exceeds the threshold. In fig. 3, curve 1 and curve 2 represent the full width at half maximum of the output spectrum near the threshold and the variation curve of the output energy with the pumping energy, respectively, and curve 3 in the inset represents the variation curve of the overall input and output energy obtained in the experiment. With the increasing of the pumping energy, the output fluorescence spectrum width gradually decreases from 46nm, and when the pumping energy reaches 3.1mJ/cm²The output spectral width was reduced to 6nm, with a center wavelength at 642 nm. The pumping energy is continuously increased, the center wavelength and the full width at half maximum of the output laser spectrum are unchanged, and the integral slope efficiency reaches 1.05 percent.

Example 2: this example is different from example 1 in that the nile red/ethanol solution in the quartz cuvette 11 was changed to a nile red/acetone solution at a concentration of 50 μ g/mL.

Example 3: this example is different from example 1 in that the nile red/ethanol solution in the quartz cuvette 11 was changed to a nile red/toluene solution at a concentration of 50 μ g/mL.

Example 4: this example is different from example 1 in that the nile red/ethanol solution in the quartz cuvette 11 was changed to a nile red/ether solution at a concentration of 50. mu.g/mL.

As shown in FIGS. 4, 5 and 6, fluorescence and laser spectra of Nile Red obtained in examples 2, 3 and 4 in different solvents are shown. Curves 1 in fig. 4, 5 and 6 each represent the fluorescence spectrum of the nile red organic solvent obtained in this example, and curves 2 each represent the laser spectrum of the nile red organic solvent obtained in this example. It is known that nile red exhibits strong fluorescence and laser properties in many organic solvents. The central wavelength of the emitted laser is different due to different polarities of the organic solvents, and is respectively 620nm, 618nm and 608nm in acetone, toluene and ether.

Example 5 in consideration of the solvatochromic properties of Nile Red, a mixture of ethyl ether and ethanol was prepared at ratios, the ratios of ethyl ether solvent to ethanol solvent were 10:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, 1:9, and 0:10, respectively, and the concentration of Nile Red in the mixture was controlled to be 50. mu.g/mL, the polar tuning spectrum shown in FIG. 7 was obtained, with the overall tuning range of 603nm to 643nm, and up to 40 nm.

Fig. 8 is a graph showing a tuned output spectrum obtained by rotating the tuned holomirror 13 based on example 5. The stronger 1 st order diffraction light is fed back to the resonant cavity through the tuning total reflection mirror 13 to continue oscillation, and the dye laser transmitted along the axial direction is finally output along the 0 th order direction of the grating diffraction. The angle of grazing incidence of the grating is fixed, and tunable output of the dye laser can be realized by rotating the tuning total reflection mirror 13. The tuning range of example 5 was extended by grating tuning, from 582nm to 660nm, achieving a tuning output of 78 nm.

Example 6 fig. 9 shows a partial optical path diagram of a dual wavelength "proportional laser" output in the present invention, a dye laser resonant cavity adopts a parallel plane cavity structure, including a plane dichroic mirror 10, a serial cuvette cell 17, an output coupling mirror 18 and an output filter 19. the plane dichroic mirror 10 is similar to in examples 1 to 5. the output coupling mirror 18 is a partial reflection mirror with a reflectivity of 85% in a range of 400nm to 700nm, the output filter 19 is a 532nm band stop filter, the serial cuvette cell 17 is formed by gluing two single-layer quartz cuvettes, each cuvette optical path is 5mm, an ethanol solution of nile red is filled in cuvettes close to pump light in the serial cuvette cell 17, the concentration is 100 μ G/mL, the concentration is maintained constant, another cuvettes are filled with an ethanol solution of nile red, the concentration is 120 μ G/mL, 100 μ G/mL, 80 μ G/mL, 60 μ G/mL, 40 μ G/mL, 20 μ G/mL and 10 μ G/mL, a spectrum concentration is obtained by gradually changing in a spectrum output range of 10 μ G/mL, a laser output curve of 10 μ G-G laser, a spectrum is obtained by a double-G laser output spectrum of a spectrum of 10-G laser, a spectrum of 10-G laser with a spectrum of 10-G concentration range of 10-G laser, a spectrum of 10-G laser, a spectrum is obtained by a spectrum-G laser, a spectrum of a spectrum obtained by a spectrum-G laser, a spectrum obtained by a spectrum-adjusting range of a spectrum of.

Finally, is summarized, the utility model discloses utilized the solvation color rendering characteristic of nile red, through the pulse pumping of frequency doubling Nd: YAG solid laser, carry out polarity tuning through changing the polarity of organic solvent, and the grating tuning is carried out to the rotatory tuning total reflection mirror, obtain group at 582nm to 660 nm's continuously adjustable output spectrum, put rhodamine 6G's ethanol solution and nile red ethanol solution in the series connection cell pond and carry out the series connection pumping again simultaneously, through the concentration that changes nile red solution, obtain group dual wavelength's "proportion laser" output, have very important application prospect in fields such as microminiature detection, terahertz light source, blood detection and extension tuning laser's tuning range.

Claims

The dye laser device with Nile red organic solvents as gain media is characterized by comprising a laser pumping source, an optical system and a dye laser resonant cavity, wherein the laser pumping source (1) is an Nd-YAG solid laser, light beams emitted by the laser pumping source (1) are subjected to frequency doubling output light through a frequency doubling optical crystal (2), output energy is adjusted by a half-wave plate (3) and a polaroid (4) together, then the light path direction is changed through a full-reflecting mirror (5) and a second full-reflecting mirror (6), the light beams pass through a beam splitter (7), part of pump light is introduced into an energy meter (16) through a third full-reflecting mirror (15) to monitor the pump energy, another part of pump laser resonant cavity is directly pumped, the pump light enters the dye laser resonant cavity after passing through a focusing lens (8) and a pinhole diaphragm (9), the dye laser resonant cavity comprises a plane dichroic mirror (10), a quartz cuvette (11) filled with different organic solvents of Nile red, a reflective blazed grating (12) and a tuned full-reflecting quartz cuvette (10) with a distance of 10mm from the quartz cuvette (10) to a quartz cuvette window (12), and a quartz reflective quartz cuvette (10) for incident light analysis, and a quartz cuvette (12) with a quartz reflective surface parallel incident light grating 12 mm distance of the quartz cuvette (10) and a quartz reflective quartz cuvette (10 mm, and a quartz cuvette 12 mm are connected to a quartz cuvette 12 mm.
2. The dye laser device using Nile Red organic solvents as gain medium according to claim 1, wherein the laser pump source (1) is a Nd: YAG solid-state laser with output laser wavelength of 1064nm, and the frequency doubling crystal passed by the Nd: YAG solid-state laser is a potassium titanyl phosphate (KTP) crystal.
3. The dye laser device using Nile Red organic solvents as gain media, according to claim 1, wherein the th holo-mirror (5), the second holo-mirror (6) and the third holo-mirror (15) are surface-coated 1064nm/532nm dichroic mirrors, and the reflectance R is greater than 99.5% around 532 nm.
4. The dye laser device using Nile Red organic solvents as gain media according to claim 1, wherein the splitting ratio of the beam splitter (7) is 1:9, wherein 90% of the energy of the pump light is reflected by the beam splitter (7) and the third holo-mirror (15) and then connected to an energy meter (16) for monitoring the pump energy, and the other 10% of the energy of the pump light is transmitted through the beam splitter (7) as a direct pump source of the dye laser gain system.
5. The dye laser device using Nile Red organic solvents as gain media, according to claim 1, wherein the pump laser transmitted through the beam splitter (7) enters the dye laser resonator after passing through the focusing lens (8) with a focal length of 17cm and the aperture stop (9) with a clear aperture of 5 mm.
6. The dye laser device using Nile Red organic solvents as gain media according to claim 1, wherein the dye laser gain system resonant cavity comprises a planar dichroic mirror (10), a quartz cuvette (11), a reflective blazed grating (12) and a tuned holophote (13), the total length of the resonant cavity is about 5cm, the planar dichroic mirror (10) is coated to ensure that the transmittance T at 532nm is more than 95% and the reflectance R at 560-700 nm is more than 95%, the quartz cuvette (11) is used for containing different organic solutions of Nile Red, the optical path is 5mm, the transmittance of two optical surfaces is more than 99.5% in the range of 400-700 nm, the pump light passes through the planar dichroic mirror (10) and the quartz cuvette (11) and enters the reflective blazed grating (12), the reflective blazed grating (12) is a common scribed grating with a blazed wavelength of 500nm, the 1200 scribed lines/mm size is 10cm, the tuned holophote (13) is a broadband reflection mirror coated with aluminum film, the tuned holophote is used as a tuned holophote, and the output of the tunable holophote is realized by continuous axial transmission of the tunable laser along the axial direction of the incident laser grating (13).