CN104104008B - A kind of optical traveling-wave light fluid dye laser of electric field regulation and control - Google Patents

Abstract

The invention discloses an optical traveling-wave optofluidic dye laser regulated by an electric field. In the prior art, the system is complex, uncontrollable, and requires a high preparation process. The invention utilizes the optical traveling wave optical resonant cavity and combines the electrorheological effect and the optical flow control technology to form a harmonic dye laser. The incident pump beam enters the optical traveling-wave optical resonant cavity sequentially through the light-transmitting hole; the optical traveling-wave optical resonant cavity is a double-layer cylindrical shell-shaped cavity, and the inner surface of the outer shell of the cylindrical shell-shaped cavity is provided with a laser reflection layer. The lasing radiation light field is reflected by multiple traveling waves and enhanced by the dye suspension to generate an outgoing laser beam; a control electric field is applied between the inner and outer shells of the cylindrical shell-shaped cavity to realize the regulation of optical resonance conditions and laser emission modes. The invention has the characteristics of an optical traveling wave cavity structure, a simple system, a high degree of miniaturization, a simple preparation process, an electric field-regulated light beam output mode, a high light energy utilization rate, a wide application range, and flexible use.

Description

An electric field regulated optical traveling wave optofluidic dye laser

technical field

The invention belongs to the field of optical technology, and relates to a laser, in particular to an optical traveling wave optofluidic dye laser regulated by an electric field, which is mainly used for photoelectric detection, spectrum technology, laser measurement, optical fiber communication, laser processing, laser marking, and laser welding , laser guidance, laser medicine, wireless optical communication, optical micro-manipulation, optical microscopy and other fields as a laser light source.

technical background

A laser is a device that uses the principle of stimulated radiation to amplify or oscillate light in certain excited substances. The essential conditions for laser generation are population inversion and gain greater than loss. Generally, laser devices include: excitation source, working medium, and resonant cavity. Excitation is the excitation of the working medium to the excited state after absorbing external energy, which creates conditions for realizing and maintaining the inversion of the number of particles; the metastable energy level of the working medium makes the stimulated radiation dominant, thereby realizing optical amplification; the resonator can be very good The length of the working substance can be shortened as much as possible, and the mode of the generated laser light can also be adjusted by changing the length of the resonant cavity. At present, there are many kinds of lasers, such as gas lasers, solid-state lasers, dye lasers, and semiconductor lasers. Recently, small-scale nano-lasers and living biological lasers have also appeared.

In recent years, microfluidic technology has been greatly developed, and the combination of microfluidic technology and optics has formed a new discipline of optofluidics (Optofluidics). As a good laser gain medium, the dye has a low threshold and a wide range of wavelength adjustment, basically covering the entire visible light region, and can also be extended to the ultraviolet and infrared regions by frequency doubling technology. The state of the suspension can be controlled using an electric field, which scientists call galvanomorphism. And this phenomenon is called "Winslow phenomenon" or "electrorheological phenomenon". The liquid with electrorheological effect is called electrorheological fluid, and electrorheological fluid is a kind of suspension under normal conditions, which can undergo liquid-solid transition under the action of electric field. When the applied electric field strength is much lower than a certain critical value, the electrorheological fluid is liquid; when the electric field strength is much higher than this critical value, it becomes solid; The microstructure changes.

In the prior art, there is a dye laser light source based on optofluidic technology, see a US patent, US patent name: Mechanically tunable elastomeric optofluidic distributed feedback dyelaser, patent number: US 7,817,698, B2. The laser has considerable advantages, but there are still some essential deficiencies: 1) The system uses optical gratings to form feedback, and constructs optical gratings in three-dimensional optical waveguides to form a distributed feedback system, and then forms an optical resonant cavity, all of which are microscopic structures , so in essence, the system has high requirements on the preparation process, and the preparation process of the laser is complicated and difficult, and the whole system is complicated; 2) Once the optical microstructure in the system is formed, it cannot be changed, and the structure of the optical resonant cavity cannot be adjusted. , resulting in the non-adjustable mode of the output beam of the laser, which affects the use range and application flexibility of the light source; 3): the linear fineness cavity structure is adopted, and the laser forms an optical standing wave in the high-definition cavity, resulting in uneven distribution of light intensity. And the optical grating is easy to interfere with the laser; 4) The pumping method is paraxial asymmetric pumping. The side of the pump beam is irradiated to the optical gain area and the area containing dye molecules. The pump beam is excited once, and the light energy utilization The efficiency is low, and the uniformity of the pumping effect is not high, which affects the quality of the laser output beam.

Contents of the invention

The purpose of the present invention is to address the deficiencies of the prior art, to provide an optical traveling wave optofluidic dye laser regulated by an electric field, which has an optical traveling wave cavity structure, a simple system, a high degree of miniaturization, a simple preparation process, an electric field regulated beam output mode, The pump light energy utilization rate is high, the use range is wide, the beam quality is good, and the use is flexible.

The basic idea of the present invention is: adopt optical traveling wave optical resonant cavity, combine electrorheological effect and optofluidic technology, and based on the working principle of dye laser, constitute a tunable dye laser with electric field control laser output mode. The incident pump beam enters the optical traveling wave optical resonant cavity sequentially through the light transmission hole; the optical traveling wave optical resonant cavity is a double-layer cylindrical shell-shaped cavity, and a dye suspension is arranged between the inner and outer shells of the cylindrical shell-shaped cavity. , the inner surface of the outer shell of the cylindrical shell-shaped cavity is provided with a laser reflection layer, and the stimulated radiation light field is reflected by multiple traveling waves, and is amplified by the dye suspension to generate an outgoing laser beam; the inner and outer layers of the cylindrical shell-shaped cavity A control electric field is applied between the shells to realize the adjustment of the optical resonance condition and the laser emission mode. The invention not only has the existing advantages of existing optofluidic lasers, but also has an optical traveling wave cavity structure, a simple system, a high degree of miniaturization, a simple preparation process, an electric field control beam output mode, a high utilization rate of pumping light energy, and a wide range of applications. Wide, good beam quality, flexible use and so on.

The invention comprises: a pumping light source and an optical traveling wave optical resonant cavity; the optical traveling wave optical resonant cavity is a double-layer cylindrical shell-shaped cavity, including an outer cylindrical shell, an inner cylindrical shell, a pumping light incident window, a laser The exit window, the dye suspension inlet and the dye suspension outlet, the output beam of the pump light source enters the optical traveling wave optical resonant cavity through the pump light incident window; the cylinders of the outer cylindrical shell and the inner cylindrical shell are symmetrical The axes are coincident, and the radial radius of the inner cylindrical shell is smaller than the radial radius of the outer cylindrical shell, the cavity between the outer cylindrical shell and the inner cylindrical shell is provided with a suspension of dye particles, and the double-layer cylindrical shell One surface of the shell-shaped cavity is provided with a fuel suspension inlet, and the other surface of the double-layer cylindrical shell-shaped cavity is provided with a fuel suspension outlet; the pump light incident window and the laser exit window are arranged on the outer cylindrical shell, and the outer cylindrical shell The outer surface of the cylindrical shell is provided with a first electrode layer, and the inner surface of the outer cylindrical shell is provided with a laser reflection layer. The stimulated radiation light field is reflected by multiple traveling waves, and is amplified by the dye suspension to generate outgoing laser light. The outer surface of the inner cylindrical shell is provided with a second electrode layer, and a voltage can be applied between the first electrode on the outer surface of the outer cylindrical shell and the second electrode layer on the outer surface of the inner cylindrical shell, for regulating the dye The microstructure change of the particle suspension realizes the regulation of the output light field.

The pumping light source is one of gas laser, semiconductor laser, solid laser and dye laser.

The first electrode layer on the outer surface of the outer cylindrical shell is one of a light-transmitting conductive film layer, a conductive metal network layer, and a metal conductive film.

The laser reflective layer on the inner surface of the outer cylindrical shell is a kind of multi-layer dielectric reflective layer and metal reflective layer with laser reflectivity greater than 90%.

The second electrode layer on the outer surface of the inner cylindrical shell is one of a light-transmitting conductive film layer, a conductive metal network layer, and a metal conductive film.

The outer surface of the inner cylindrical shell can be provided with one of a multi-layer dielectric reflective layer and a metal reflective layer with a laser reflectivity greater than 90% on the side of the light-transmitting conductive film layer close to the dye particle suspension.

The dye suspension inlet and the dye suspension outlet can be arranged at positions on the optical traveling wave optical resonant cavity that do not affect beam propagation.

The pump light incident window is a window with a pump light transmittance greater than 90%.

A DC voltage or an AC voltage can be applied between the first electrode and the second electrode.

The working process of the device of the present invention is as follows: the output light beam of the pump light source enters the optical traveling wave optical resonant cavity through the pump light incident window; the cylindrical symmetry axes of the outer cylindrical shell and the inner cylindrical shell coincide, and The radial radius of the cylinder of the inner cylindrical shell is smaller than the radial radius of the outer cylindrical shell, and the cavity between the outer cylindrical shell and the inner cylindrical shell is provided with a dye particle suspension, and the dye particle suspension is obtained from the dye suspension The inlet flows in, and the dye suspension outlet flows out. The dye suspension inlet and the dye suspension outlet are set on the shell surface of the optical traveling wave optical resonator where no light field hits; the pump light incident window and the laser exit window are set on the outer cylinder On the shell, the outer surface of the outer cylindrical shell is provided with a first electrode layer, and the inner surface of the outer cylindrical shell is provided with a laser reflection layer, and the stimulated radiation light field is reflected by multiple traveling waves and passed through the dye suspension Gain, to generate the outgoing laser beam; the outer surface of the inner cylindrical shell is provided with a second electrode layer, and a voltage can be applied between the first electrode layer on the outer surface of the outer cylindrical shell and the second electrode layer on the outer surface of the inner cylindrical shell , used to regulate the microstructure change of the dye particle suspension to realize the regulation of the output light field.

The dye molecule and its use, microfluidic technology, and electrorheological fluid preparation technology in the device of the invention are all mature technologies. The invention point of the present invention is to adopt optical traveling wave optical resonant cavity, combine electrorheological effect and optofluidic technology, and based on the working principle of dye laser, constitute a tunable dye laser with electric field regulation laser output mode, providing a kind of Fluidic lasers have existing advantages, such as optical traveling wave cavity structure, simple system, high degree of miniaturization, simple preparation process, electric field control beam output mode, high utilization rate of pump light energy, wide application range, good beam quality, and easy to use Optical traveling-wave optofluidic dye lasers with flexible and other characteristics controlled by electric field.

Compared with prior art, the advantages of the present invention:

1) In the prior art, the system uses optical gratings to form feedback, constructing optical gratings in three-dimensional optical waveguides to form a distributed feedback system, and then forming optical resonant cavities, all of which are microscopic structures, so that the system is essentially the best for the preparation process. The requirements are very high, the process of preparing the laser is complicated and difficult, and the whole system is complicated; the present invention adopts an optical traveling wave optical resonator, based on the working principle of dye laser, and combines the principle of dye laser, optofluidic control and electrorheological effect to give full play to Based on the characteristics of optical traveling wave optical resonator and optofluidic control, an electric field regulated optical traveling wave optofluidic dye laser is proposed, which not only has the existing characteristics of existing optofluidic lasers, but also has an optical traveling wave cavity structure, simple system, and miniaturization High degree, simple preparation process and so on.

2) In the prior art, once the optical microstructure is formed, it cannot be changed, and the structure of the optical resonant cavity cannot be adjusted. In this way, the mode of the output beam of the laser cannot be adjusted, which affects the range of use of the light source and the flexibility of application; in the present invention, the electrorheological effect Combined with optofluidic technology to form a tunable optical resonant cavity, based on the working principle of dye lasers, a tunable laser with an electric field regulated laser output mode is formed to realize the electric field regulated laser output beam characteristics and more flexibly control the output laser, so the present invention can realize The change of the output mode of the laser beam realizes the controllable output beam mode of high beam quality, expands the application range, and improves the use flexibility of the laser.

3) The prior art adopts a linear fineness cavity structure, and the laser forms an optical standing wave in the high-precision cavity, resulting in uneven distribution of light intensity, and the optical grating is easy to interfere with the laser; the present invention uses an optical traveling wave optical resonant cavity For laser optical feedback, since the optical traveling wave does not have the light field node phenomenon in the standing wave, the light field distribution of the traveling wave is relatively uniform, which effectively reduces the influence of the laser light field on the dye in the resonant cavity, and has significantly reduced Influence of thermal effect of light field on laser working performance.

4) The pumping method in the prior art is paraxial asymmetric pumping. The side of the pump beam irradiates the optical gain area and the area containing dye molecules. The pump beam is excited once, and the utilization rate of light energy is low. The uniformity of the effect is not high, which affects the quality of the output beam of the laser; the present invention uses the pumping beam to be coupled into the optical traveling wave optical resonator for pumping, and the pumping light field can propagate in the resonating cavity, effectively improving the pumping light energy Utilization efficiency, and because there is no incidence on the pump beam, the present invention can realize axisymmetric optical pumping.

Description of drawings

FIG. 1 is a schematic diagram of a sectional structure of a symmetry axis of a vertical cylindrical surface of the present invention.

Fig. 2 is a schematic diagram of the section structure along the symmetry axis of the cylindrical surface of the present invention.

detailed description

The present invention will be further described below in conjunction with drawings and embodiments.

As shown in Figure 1, an optical traveling-wave optofluidic dye laser regulated by an electric field includes a pump light source 1 and an optical traveling-wave optical resonant cavity 2; the optical traveling-wave optical resonant cavity 2 is a double-layer cylindrical shell-shaped cavity, including an outer Layer cylindrical shell 201, inner cylindrical shell 202, pump light incident window 203, laser exit window 204, dye suspension inlet 205 and dye suspension exit 206, the output beam of pump light source 1 passes through the pump light incident window 203 Incident into the cavity of the optical traveling wave optical resonant cavity 2; the cylindrical symmetry axes of the outer cylindrical shell 201 and the inner cylindrical shell 202 coincide, and the radial radius of the inner cylindrical shell 202 is smaller than that of the outer cylindrical shell 201 radial radius, the cavity between the outer cylindrical shell 201 and the inner cylindrical shell 202 is provided with a dye particle suspension 207, the dye particle suspension 207 flows in from the dye suspension inlet 205, and flows from the dye suspension outlet 206 Outflow, the dye suspension inlet 205 and the dye suspension outlet 206 are arranged on the shell surface of the optical traveling wave optical resonator 2 where no light field hits; the pump light incident window 203 and the laser exit window 204 are arranged on the outer cylindrical shell 201 Above, the outer surface of the outer cylindrical shell 201 is provided with a first electrode layer, and the inner surface of the outer cylindrical shell 201 is provided with a laser reflection layer. gain, to generate outgoing laser beams; the outer surface of the inner cylindrical shell 202 is provided with a second electrode layer, the first electrode layer on the outer surface of the outer cylindrical shell 201 and the second electrode layer on the outer surface of the inner cylindrical shell 202 A voltage can be applied between them to regulate the change of the microstructure of the dye particle suspension 207 to realize the regulation of the output light field.

In this embodiment, in this embodiment, the pumping light source 1 adopts a light beam with a wavelength of 532 nanometers emitted by a frequency-doubled YAG laser; the optical traveling wave optical resonator 2 is made of quartz material; the outer cylindrical shell 201 is 6.8 mm in diameter , a cylindrical tube with a thickness of 1 mm; the inner cylindrical shell 202 is a cylindrical tube with a diameter of 4 mm and a thickness of 1 mm; the pump light incident window 203 and the laser exit window 204 are both arranged on the outer cylindrical shell 201, and the pump The pump light incident window 203 is a window with a pump light transmittance of 97% and a laser reflectance of 99%, and the laser exit window 204 is a window with a laser reflectance of 90%; the dye particles are rhodamine 6G molecular composite particles, The dye particle suspension 207 is rhodamine 6G molecular composite particles dispersed in the insulating oil; the dye suspension inlet 205 and the dye suspension outlet 206 are arranged in the side circular ring shell of the optical traveling wave optical resonant cavity 2 where no light field hits On the surface, the first electrode layer on the outer surface of the outer cylindrical shell 201 and the second electrode layer on the outer surface of the inner cylindrical shell 202 are transparent conductive film layers, and a DC voltage is applied between them.

The working process of the device of the present invention is as follows: the output beam of the pumping light source 1 enters the cavity of the optical traveling wave optical resonant cavity 2 through the pumping light incident window 203; the cylinders of the outer cylindrical shell 201 and the inner cylindrical shell 202 are symmetrical The axes are coincident, and the radial radius of the inner cylindrical shell 202 is smaller than the radial radius of the outer cylindrical shell 201, and the cavity between the outer cylindrical shell 201 and the inner cylindrical shell 202 is provided with a suspension of dye particles 207, the dye particle suspension 207 flows in from the dye suspension inlet 205, and flows out from the dye suspension outlet 206; the pump light incident window 203 and the laser exit window 204 are arranged on the outer cylindrical shell 201, and the outer cylindrical shell 201 The outer surface is provided with a first electrode layer, and the inner surface of the outer cylindrical shell 201 is provided with a laser reflection layer. The stimulated radiation light field is reflected by multiple traveling waves, and is amplified by the dye suspension to generate an outgoing laser beam; the inner layer The outer surface of the cylindrical shell 202 is provided with a second electrode layer, and a voltage can be applied between the first electrode layer on the outer surface of the outer cylindrical shell 201 and the second electrode layer on the outer surface of the inner cylindrical shell 202 for controlling The change of the microstructure of the dye particle suspension 207 realizes the adjustment of the output light field. This embodiment has successfully achieved a high-quality adjustable output of 570 nanometers. The present invention not only has the existing advantages of existing optofluidic lasers, but also has an optical traveling wave cavity structure, a simple system, a high degree of miniaturization, a simple preparation process, and electric field control. Beam output mode, high utilization rate of pump light energy, wide range of use, good beam quality, and flexible use.

Claims (9)

1. the optical traveling-wave light fluid dye laser that a kind of electric field regulates and controls, including：Pump light source and optical traveling-wave optical resonance Chamber；Optical traveling-wave optical resonator is double cylindrical shell shape cavity, including outer layer cylindrical shell, internal layer cylindrical shell, pump light The outlet of incidence window, laser emitting window, dye suspensions entrance and dye suspensions, pump light source outgoing beam is by pumping Light incidence window is incided in optical traveling-wave optical resonator chamber；The cylinder of outer layer cylindrical shell and internal layer cylindrical shell is symmetrical Axle coincides, and internal layer cylindrical shell cylindrical radial radius be less than outer layer cylindrical shell radial direction radius, outer layer cylindrical shell and Cavity between internal layer cylindrical shell is provided with dye granule suspension, and a surface of double cylindrical shell shape cavity is provided with dyestuff Suspension inlet, another surface of double cylindrical shell shape cavity is provided with dye suspensions outlet；Pump light incidence window and swash Light exit window mouthful is arranged on outer layer cylindrical shell, and the outer surface of outer layer cylindrical shell is provided with first electrode layer, outer layer cylinder The inner surface setting of housing has laser reflection layer, and stimulated radiation light field reflects by multiple traveling wave, and is suspended by dye granule Liquid gain, produces outgoing laser beam；The outer surface of internal layer cylindrical shell is provided with the second electrode lay, outer layer cylindrical shell outer surface First electrode layer and the second electrode lay of internal layer cylindrical shell outer surface between can be with applied voltage, for regulating and controlling dye granule Suspension microstructure change realizes that output light field regulates and controls.

2. the optical traveling-wave light fluid dye laser that a kind of electric field according to claim 1 regulates and controls, it is characterised in that：Institute The pump light source stated is gas laser, semiconductor laser, solid state laser, one kind of dye laser.

3. the optical traveling-wave light fluid dye laser that a kind of electric field according to claim 1 regulates and controls, it is characterised in that：Institute The first electrode layer of the outer surface of the outer layer cylindrical shell stated is thin light transmitting electro-conductive film layer, conducting metal Internet, metallic conduction One kind of film.

4. the optical traveling-wave light fluid dye laser that a kind of electric field according to claim 1 regulates and controls, it is characterised in that：Institute The laser reflection layer of the inner surface of the outer layer cylindrical shell stated is the multilayer dielectricity reflecting layer for laser reflectivity more than 90% With one kind of metallic reflector.

5. the optical traveling-wave light fluid dye laser that a kind of electric field according to claim 1 regulates and controls, it is characterised in that：Institute The second electrode lay of the outer surface of the internal layer cylindrical shell stated be light transmitting electro-conductive film layer,

Conducting metal Internet, one kind of conductive metal film.

6. the optical traveling-wave light fluid dye laser that a kind of electric field according to claim 5 regulates and controls, it is characterised in that：Institute The outer surface of the internal layer cylindrical shell stated is provided with for laser in light transmitting electro-conductive film layer near the side of dye granule suspension Multilayer dielectricity reflecting layer of the reflectivity more than 90% or metallic reflector.

7. the optical traveling-wave light fluid dye laser that a kind of electric field according to claim 1 regulates and controls, it is characterised in that：Institute Dye suspensions entrance and the dye suspensions outlet stated can be arranged on optical traveling-wave optical resonator and not influence light beam to pass On the position broadcast.

8. the optical traveling-wave light fluid dye laser that a kind of electric field according to claim 1 regulates and controls, it is characterised in that：Institute The pump light incidence window stated is the window more than 90% to pump beam transmitance.

9. the optical traveling-wave light fluid dye laser that a kind of electric field according to claim 1 regulates and controls, it is characterised in that：Institute Apply DC voltage between the first electrode layer and the second electrode lay stated or apply alternating voltage.