阅读说明：本技术 上转换激发单元及其激光器 (Up-conversion excitation unit and laser thereof ) 是由 王婷 余兆丰 于 2020-05-14 设计创作，主要内容包括：本发明属于激光器技术领域,尤其涉及一种上转换激发单元,所述上转换激发单元包括：相对且平行设置的全反射镜和非全反射镜,以及设置在所述全反射镜和所述非全反射镜之间的上转换单元；所述上转换单元包括微晶载体和分布在所述微晶载体内部的上转换材料。本发明提供的上转换激发单元,通过在上转换单元的相对两侧,依次引入非全反射镜和全反射镜,提高腔体内上转换材料对入射光波的吸收效率,从而提升上转换材料对光波的转化效率,增加上转换激发单元的激光发射效率,减少了激发光源的溢出损失。(The invention belongs to the technical field of lasers, and particularly relates to an up-conversion excitation unit, which comprises: the device comprises a total reflecting mirror, a non-total reflecting mirror and an up-conversion unit, wherein the total reflecting mirror and the non-total reflecting mirror are arranged oppositely and in parallel; the upconversion unit comprises a microcrystalline support and an upconversion material distributed inside the microcrystalline support. According to the up-conversion excitation unit provided by the invention, the non-total-reflection mirrors and the total-reflection mirrors are sequentially introduced into the two opposite sides of the up-conversion unit, so that the absorption efficiency of the up-conversion material in the cavity on incident light waves is improved, the conversion efficiency of the up-conversion material on the light waves is improved, the laser emission efficiency of the up-conversion excitation unit is increased, and the overflow loss of an excitation light source is reduced.)

1. An up-conversion excitation unit, characterized in that the up-conversion excitation unit comprises: the device comprises a total reflecting mirror, a non-total reflecting mirror and an up-conversion unit, wherein the total reflecting mirror and the non-total reflecting mirror are arranged oppositely and in parallel; the upconversion unit comprises a microcrystalline support and an upconversion material distributed inside the microcrystalline support.

2. The upconversion excitation unit according to claim 1, wherein the non-total reflection mirror is selected from a group consisting of mirrors having a refractive index of 80% to 95% for incident light.

3. The upconversion excitation unit according to claim 1 or 2, wherein the microcrystalline support is selected from a crystalline material or a microcrystalline glass; and/or the presence of a gas in the gas,

the up-conversion material comprises a nanocrystalline carrier and rare earth ions doped in the nanocrystalline carrier.

4. The upconversion excitation unit according to claim 3, wherein the nanocrystalline carrier is selected from the group consisting of: NaYF₄、CaF₂、Ba₂LaF₇、LaF₃、NaGdF₄At least one of; and/or the presence of a gas in the gas,

the rare earth ions include: er³⁺、Ho³⁺、Tm³⁺And Yb, and³⁺(ii) a Or, Er³⁺、Ho³⁺、Tm³⁺And Yb, and³⁺and Gd³⁺(ii) a Or, Pr³⁺And Gd³⁺。

5. The upconversion excitation unit according to claim 3, wherein the crystalline material is selected from the group consisting of: at least one of yttrium fluoride crystal and yttrium aluminum garnet crystal; and/or the presence of a gas in the gas,

the microcrystalline glass is selected from: 45SiO 2₂-15Al₂O₃-12Na₂CO₃-Ba₂LaF₇、40SiO₂-8AlF₃-4TiO₂-20BaF₂、40SiO₂-13Al₂O₃-10Na₂CO₃-20BaF₂、InF₃-25ZnF₂-25SrF₂-15BaF₂-5NaF-1GaF₃、40SiO₂-20Al₂O₃-20-xNa₂O-5MgO-10NaYF₄At least one of (1).

6. The upconversion excitation unit according to claim 4 or 5, wherein a molar ratio of the nanocrystalline carrier to the rare earth ion in the upconversion material is 1: (0.1 to 1); and/or the presence of a gas in the gas,

in the up-conversion unit, the molar ratio of the microcrystalline carrier to the up-conversion material is (1-2): (1-5).

7. The upconversion excitation unit according to claim 6, wherein the upconversion excitation unit is a cuboid, and a vertical distance between the total reflection mirror and the non-total reflection mirror is 3 mm to 3 cm.

8. The upconversion excitation unit according to claim 1, 2, 4, 5, or 7, wherein an absorption rate of the upconversion unit to an incident light source is 0.5l.mol^-1/cm^-1～10L.mol^-1/cm^-1。

9. An upconversion laser comprising the upconversion excitation unit according to any one of claims 1 to 8 and a light source unit, wherein an incident light source emitted from the light source unit enters the upconversion excitation unit from a side of the non-total reflection mirror.

10. The upconversion laser according to claim 9, wherein the incident light source enters the upconversion excitation unit perpendicular to the non-total reflection mirror; and/or the presence of a gas in the gas,

the light source unit is selected from a laser light source with the emission wavelength of 400 nm-1200 nm; and/or the presence of a gas in the gas,

the light source unit is selected from a pulsed laser or a continuous laser.

Technical Field

The invention belongs to the technical field of lasers, and particularly relates to an up-conversion excitation unit and an up-conversion laser.

Background

In recent years, up-conversion lasers have attracted attention because they can convert low-energy photons into high-energy photons, and in particular, can convert infrared light into visible light and reach a practical level. The ultraviolet light source can be applied to photo-biological imaging, can also be applied to high-energy deep ultraviolet laser with adjustable wavelength, and is particularly applied to ultraviolet sterilization, communication and the like. However, with the discovery of materials, the great problem faced by up-conversion materials is how to improve the luminous efficiency. The current upconversion materials have low luminous efficiency, especially for deep ultraviolet lasers, which is generally lower than 1%, and this will significantly limit the applications, thereby leading to the development of upconversion lasers being in a situation before being stopped. Even if it is proposed to start with the up-conversion of materials, a surface plasmon resonance method is introduced by introducing a core-shell structure; or the surface defects of the laser are repaired, etc. to realize the enhancement of the up-conversion luminescent material, thereby realizing the increase of the efficiency of the up-conversion laser. However, even if the optimization of the materials is started, the light emitting efficiency of the up-conversion material is still very low, and it is difficult to break through the situation of low light emitting efficiency at present. The laser efficiency of the upconversion laser is effectively improved, and the realization of the high-efficiency upconversion laser is still very difficult. Especially for short-band multi-photon up-conversion. Therefore, it is very desirable to improve the laser efficiency of the upconversion laser.

Disclosure of Invention

The invention aims to provide an up-conversion excitation unit, and aims to solve the technical problem of low laser efficiency of the existing up-conversion laser.

The invention aims to provide an up-conversion laser.

In order to achieve the purpose of the invention, the technical scheme adopted by the invention is as follows:

an up-conversion excitation unit, the up-conversion excitation unit comprising: the device comprises a total reflecting mirror, a non-total reflecting mirror and an up-conversion unit, wherein the total reflecting mirror and the non-total reflecting mirror are arranged oppositely and in parallel; the upconversion unit comprises a microcrystalline support and an upconversion material distributed inside the microcrystalline support.

Preferably, the non-total reflection mirror is selected from mirrors having a refractive index of 80% to 95% with respect to incident light.

Preferably, the microcrystalline support is selected from a crystalline material or a microcrystalline glass; and/or the presence of a gas in the gas,

the up-conversion material comprises a nanocrystalline carrier and rare earth ions doped in the nanocrystalline carrier.

Preferably, the nanocrystalline support is selected from: NaYF₄、CaF₂、Ba₂LaF₇、LaF₃、NaGdF₄At least one of; and/or the presence of a gas in the gas,

the rare earth ions include: er³⁺、Ho³⁺、Tm³⁺And Yb, and³⁺(ii) a Or, Er³⁺、Ho³⁺、Tm³⁺And Yb, and³⁺and Gd³⁺(ii) a Or, Pr³⁺And Gd³⁺。

Preferably, the crystalline material is selected from: at least one of yttrium fluoride crystal and yttrium aluminum garnet crystal; and/or the presence of a gas in the gas,

the microcrystalline glass is selected from: 45SiO 2₂-15Al₂O₃-12Na₂CO₃-Ba₂LaF₇、40SiO₂-8AlF₃-4TiO₂-20BaF₂、40SiO₂-13Al₂O₃-10Na₂CO₃-20BaF₂、InF₃-25ZnF₂-25SrF₂-15BaF₂-5NaF-1GaF₃、40SiO₂-20Al₂O₃-20-xNa₂O-5MgO-10NaYF₄At least one of (1).

Preferably, in the up-conversion material, the molar ratio of the nanocrystalline carrier to the rare earth ion is 1: (0.1 to 1); and/or the presence of a gas in the gas,

in the up-conversion unit, the molar ratio of the microcrystalline carrier to the up-conversion material is (1-2): (1-5).

Preferably, the up-conversion excitation unit is a cuboid, and a vertical distance between two opposite side surfaces of the total reflection mirror and the non-total reflection mirror is 3 mm to 3 cm.

Preferably, the absorption rate of the up-conversion unit to the incident light source is 0.5l.mol^-1/cm^-1～10L.mol^-1/cm^-1。

Correspondingly, the upconversion laser comprises the upconversion excitation unit and the light source unit, wherein an incident light source emitted by the light source unit enters the upconversion excitation unit from one side of the non-total reflection mirror.

Preferably, the incident light source enters the up-conversion excitation unit perpendicular to the non-total reflection mirror; and/or the presence of a gas in the gas,

the light source unit is selected from a laser light source with the emission wavelength of 400 nm-1200 nm; and/or the presence of a gas in the gas,

the light source unit is selected from a pulsed laser or a continuous laser.

The up-conversion excitation unit provided by the invention comprises: the device comprises a total reflecting mirror, a non-total reflecting mirror and an up-conversion unit, wherein the total reflecting mirror and the non-total reflecting mirror are arranged oppositely and in parallel; the upconversion unit comprises a microcrystalline support and an upconversion material distributed inside the microcrystalline support. The total reflection mirrors arranged oppositely can effectively inhibit the overflow of the wave band of the light source, so that the incident light reaching the total reflection mirrors is totally reflected back to the up-conversion unit. When the incident light moves to the non-total reflection mirror, the light source overflow is reduced due to the refraction effect of the non-total reflection mirror, the light source is limited in the up-conversion unit as far as possible, and the absorption efficiency of the up-conversion material in the up-conversion unit to the light source is improved, so that the conversion efficiency of the up-conversion material to the incident light source is improved. According to the upconversion excitation unit provided by the invention, the non-total reflection mirror and the total reflection mirror are sequentially introduced into the two opposite sides of the upconversion unit, so that the absorption efficiency of an upconversion material in the cavity on incident light waves is improved, the conversion efficiency of the upconversion material on the light waves is improved, the laser emission efficiency of the upconversion excitation unit is increased, and the overflow loss of an excitation light source is reduced.

According to the up-conversion laser, the light source unit emits the incident light source, the incident light source enters the up-conversion excitation unit from one side of the non-total reflection mirror, the non-total reflection mirror and the total reflection mirror which are oppositely arranged in the up-conversion excitation unit limit the incident light source in the up-conversion unit, and the absorption efficiency of the up-conversion material in the up-conversion unit on the light source is improved, so that the conversion efficiency of the up-conversion material on the incident light source is improved, and the laser efficiency of the laser is improved.

Drawings

Fig. 1 is a schematic diagram of an operation of an upconversion laser according to an embodiment of the present invention.

FIG. 2 is a graph showing the relationship between the cavity length and the excitation absorption rate of the upconversion excitation unit in examples 1 to 3 of the present invention.

Detailed Description

In order to make the purpose, technical solution and technical effect of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention is clearly and completely described, and it is obvious that the described embodiments are a part of the embodiments of the present invention, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art without any inventive step in connection with the embodiments of the present invention shall fall within the scope of protection of the present invention.

In the description of the present invention, it is to be understood that the terms "first", "second" and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

The weight of the related components mentioned in the description of the embodiments of the present invention may not only refer to the specific content of each component, but also represent the proportional relationship of the weight among the components, and therefore, the content of the related components is scaled up or down within the scope disclosed in the description of the embodiments of the present invention as long as it is in accordance with the description of the embodiments of the present invention. Specifically, the weight described in the description of the embodiment of the present invention may be a unit of mass known in the chemical industry field, such as μ g, mg, g, and kg.

The embodiment of the invention provides an up-conversion excitation unit, which comprises: the upconversion excitation unit includes: the device comprises a total reflecting mirror, a non-total reflecting mirror and an up-conversion unit, wherein the total reflecting mirror and the non-total reflecting mirror are arranged oppositely and in parallel; the upconversion unit comprises a microcrystalline support and an upconversion material distributed inside the microcrystalline support.

The up-conversion excitation unit provided by the embodiment of the invention comprises: the upconversion excitation unit includes: the device comprises a total reflecting mirror, a non-total reflecting mirror and an up-conversion unit, wherein the total reflecting mirror and the non-total reflecting mirror are arranged oppositely and in parallel; the upconversion unit comprises a microcrystalline support and an upconversion material distributed inside the microcrystalline support. The total reflection mirrors arranged oppositely can effectively inhibit the overflow of the wave band of the light source, so that the incident light reaching the total reflection mirrors is totally reflected back to the up-conversion unit. When the incident light moves to the non-total reflection mirror, the light source overflow is reduced due to the refraction effect of the non-total reflection mirror, the light source is limited in the up-conversion unit as far as possible, and the absorption efficiency of the up-conversion material in the up-conversion unit to the light source is improved, so that the conversion efficiency of the up-conversion material to the incident light source is improved. According to the upconversion excitation unit provided by the invention, the non-total reflection mirror and the total reflection mirror are sequentially introduced into the two opposite sides of the upconversion unit, so that the absorption efficiency of an upconversion material in the cavity on incident light waves is improved, the conversion efficiency of the upconversion material on the light waves is improved, the laser emission efficiency of the upconversion excitation unit is increased, and the overflow loss of an excitation light source is reduced.

In the embodiment of the invention, the total reflector has the refractive index of 100% for incident light, and totally reflects the incident light source to prevent the incident light source from overflowing. In some embodiments, the non-total reflecting mirrors are selected from mirrors having a refractive index of 80% to 95% for incident light. According to the embodiment of the invention, the non-total reflection mirror with the refractive index of 80% -95% is arranged on one side of the upper conversion unit, so that most incident light can be limited in the upper conversion unit after the incident light enters the upper conversion unit from the reflection mirror, and the photon overflow is prevented. When the refractive index of the non-total reflection mirror to incident light is 80% -95%, the absorption rate of the up-conversion material to the incident light can be improved by about 40%, the absorption and conversion efficiency of the up-conversion material to the incident light is remarkably improved, and therefore the laser emission efficiency of the laser is effectively improved.

In some embodiments, the upconverting material includes a nanocrystalline support and a rare earth ion doped in the nanocrystalline support. According to the embodiment of the invention, the rare earth ions are doped in the nanocrystalline carrier in an ion substitution mode and the like, and when the nanocrystalline carrier is excited by an incident light source, the rare earth ions can emit light with a wavelength shorter than the excitation wavelength, namely anti-Stokes light.

In some embodiments, the rare earth ions include: er³⁺、Ho³⁺、Tm³⁺And Yb, and³⁺. In the upconversion unit of the upconversion excitation unit of the embodiment of the present invention, Yb³⁺The ions can absorb 980nm excitation light energy and transfer the energy to Er³⁺、Ho³⁺、Tm³⁺Plasma of Er³⁺、Ho³⁺、Tm³⁺And the laser emission of the short-wavelength deep ultraviolet light is realized by the energy level transition of the plasma.

In some embodiments, the rare earth ions include: er³⁺、Ho³⁺、Tm³⁺And Yb, and³⁺and Gd^{3 +}. In the upconversion unit of the upconversion excitation unit of the embodiment of the invention, the rare earth ions further comprise Gd³⁺，Gd³⁺Plays a role of a bridge of energy transfer in the emission of rare earth ion excitation light, when Yb³⁺The energy of exciting light absorbed by ions is transferred to Er³⁺、Ho³⁺、Tm³⁺Then Er³⁺、Ho³⁺、Tm³⁺The generated energy level transition can emit light of different wave bands, Gd³⁺Can convert Er into³⁺、Ho³⁺、Tm³⁺The energy of the emitted light with different wave bands, namely the light with long wavelength, is transferred to the light with short wavelength, so that the light with higher energy band is emitted, the selectivity of the rare earth ion luminescence wave band is improved, and the emission efficiency of the light with higher energy of the up-conversion excitation unit is improved.

In some embodiments, the rare earth ions include: pr (Pr) of³⁺And Gd³⁺. In the upconversion unit of the upconversion excitation unit of the embodiment of the invention, through Pr³⁺The ions absorb the excitation light energy and then pass through Pr³⁺The ion transfers the absorbed photon to Gd via multiphoton absorption³⁺And ions are used for realizing short-wavelength high-energy up-conversion luminescence.

In some embodiments, the nanocrystalline support is selected from: NaYF₄、CaF₂、Ba₂LaF₇、LaF₃、NaGdF₄At least one of (1). NaYF is used as the up-conversion material in the embodiment of the invention₄、CaF₂、Ba₂LaF₇、LaF₃、NaGdF₄At least one of the rare earth ions is used as a nanocrystalline carrier, the rare earth ions are combined on the nanocrystalline carrier, and the adopted nanocrystalline carrier has the characteristics of low phonon energy, high fluorescence efficiency and the like, and can provide a carrier matrix for the rare earth ions to be excited to realize the deep ultraviolet up-conversion luminescence. In some embodiments, the nanocrystalline carrier may be grown into a nanocrystalline carrier in the microcrystalline carrier by annealing or the like, and during the process of precipitating the nanocrystalline carrier, the rare earth ions and the nanocrystalline carrier material undergo ion replacement, so that crystal particles containing the rare earth ions are formed in the microcrystalline carrier, and an environmental condition is provided for the luminescence of the rare earth ions. The nanocrystal carrier of the embodiment of the invention includes but is not limited to NaYF₄、CaF₂、Ba₂LaF₇、LaF₃、NaGdF₄The material can also be other nanocrystalline carriers as long as a carrier matrix is provided for the rare earth ions to be excited to realize up-conversion luminescence.

In some embodiments, the microcrystalline carrier is selected from the group consisting of: crystal material and microcrystalline glass. In the gain cavity of the upconversion excitation unit in the embodiment of the invention, the crystal material or the microcrystalline glass is used as the carrier of the upconversion excitation unit, and the materials have excellent thermal stability and chemical stability, so that the material is not only suitable for high-temperature excitation, but also improves the excitation resistance and the service life of the upconversion excitation unit, is suitable for high-density excitation, and improves the laser emission efficiency of the upconversion excitation unit.

In some embodiments, the crystalline material is selected from: at least one of yttrium fluoride crystal and yttrium aluminum garnet crystal. In some embodiments, the glass-ceramic is selected from: 45SiO 2₂-15Al₂O₃-12Na₂CO₃-Ba₂LaF₇、40SiO₂-8AlF₃-4TiO₂-20BaF₂、40SiO₂-13Al₂O₃-10Na₂CO₃-20BaF₂、InF₃-25ZnF₂-25SrF₂-15BaF₂-5NaF-1GaF₃、40SiO₂-20Al₂O₃-20-xNa₂O-5MgO-10NaYF₄The microcrystalline glass has the excellent characteristics of high mechanical strength, excellent insulating property, less dielectric loss, stable dielectric constant, adjustable thermal expansion coefficient in a large range, chemical corrosion resistance, wear resistance, good thermal stability, high use temperature and the like, so that the tolerance of the up-conversion excitation unit, such as thermal stability, chemical stability and the like, can be effectively improved, and the laser emission stability and the service life of the up-conversion excitation unit are improved.

In some embodiments, the molar ratio of nanocrystalline support to rare earth ion in the upconverting material is 1: (0.1 to 1). In the upconversion unit of the upconversion excitation unit provided in the embodiment of the present invention, the rare earth ions are doped into the crystal lattice of the nanocrystal carrier in an ion substitution manner to form the upconversion material, and specifically, the doping of the nanocrystal carrier can be realized by the substitution of the rare earth ions on the lattice position with the equivalent radius in the nanocrystal carrier. The molar ratio of nanocrystalline carrier to rare earth ion may be 1: (0.1-1), when the doping proportion of the rare earth ions in the nanocrystalline carrier is 1:1, each nanocrystalline carrier is doped with a rare earth ion up-conversion material through ion substitution. The higher the doping proportion of the rare earth ions in the microcrystalline matrix in the up-conversion unit is, the better the conversion effect of the laser on incident light is.

In some embodiments, the molar ratio of the microcrystalline support to the upconverting material in the upconverting unit is (1-2): (1-5), if the molar ratio of the up-conversion material is too high, the up-conversion material is easy to agglomerate in the microcrystalline carrier, the dispersion uniformity is poor, the light transmittance of the laser is affected, the laser with poor light transmittance is not beneficial to exciting rare earth ions by exciting light and is not beneficial to light conduction in the laser, the light loss is large, and the light emitting efficiency is low; if the molar ratio of the upconversion material is too low, the upconversion luminescence efficiency of the rare earth ions in the microcavity laser is reduced. In some embodiments, the molar ratio of the microcrystalline support to the upconverting material in the upconversion excitation unit may be 1:1, 2:1, 1:2, 1:3, 1:5, 2:3 or 2: 5.

In some embodiments, the upconversion excitation unit is a cuboid, and the vertical distance between two opposite side surfaces of the total reflection mirror and the non-total reflection mirror is 3 mm-3 cm. The up-conversion excitation unit provided by the embodiment of the invention is a cuboid, the vertical distance between two opposite side surfaces of the total reflector and the non-total reflector is 3 mm-3 cm, an incident light source enters the laser from one side of the non-total reflector, most of the light sources are limited in the up-conversion unit through the reflection of the incident light source by the total reflector and the non-total reflector which are oppositely arranged, and the light absorption efficiency of the up-conversion material to the incident light source is improved, so that the up-conversion and excitation efficiency is improved. If the vertical distance between two opposite side surfaces of the total reflection mirror and the non-total reflection mirror is too short, the feedback motion of incident light in the up-conversion unit is not facilitated, and the absorption of the incident light by an up-conversion material is not facilitated; when the vertical distance between two opposite side surfaces of the total reflection mirror and the non-total reflection mirror is too long and is more than 3 cm, the absorption efficiency of the up-conversion material to the incident light source is not increased basically.

In some embodiments, the absorption rate of the incident light by the up-conversion unit is 0.5l.mol^-1/cm^-1～10L.mol^-1/cm^-1. The absorption rate of the up-conversion unit in the up-conversion excitation unit provided by the invention to incident light is 0.5L.mol^-1/cm^-1～10L.mol^-1/cm^-1High absorption efficiency, wide absorption rate range and wide application range.

Correspondingly, the embodiment of the invention also provides an upconversion laser, which comprises the upconversion excitation unit and the light source unit, wherein an incident light source emitted by the light source unit enters the upconversion excitation unit from one side of the non-total reflection mirror.

According to the up-conversion laser provided by the embodiment of the invention, the incident light source is emitted by the light source unit, the incident light source enters the up-conversion excitation unit from one side of the non-total reflection mirror, the non-total reflection mirror and the total reflection mirror which are oppositely arranged in the up-conversion excitation unit limit the incident light source in the up-conversion unit, and the absorption efficiency of the up-conversion material in the up-conversion unit to the light source is improved, so that the conversion efficiency of the up-conversion material to the incident light source is improved, and the laser efficiency of the laser is improved.

In some embodiments, the incident light source enters the upconversion excitation unit perpendicular to the non-total reflection mirror, so that the incident light source can more easily enter the upconversion unit, and light loss caused by refraction of the non-total reflection mirror on the incident light source is reduced. And simultaneously, the parallel feedback of incident light on the up-conversion unit is facilitated.

In some embodiments, the light source unit is selected from a laser light source emitting light having a wavelength of 400nm to 1200 nm. The upconversion laser provided by the embodiment of the invention can realize conversion of incident light with a long wavelength of 400-1200 nm by selecting an upconversion material, emits light with a short wavelength, high frequency and high energy, and has wide applicable functional wavelength range and strong practicability.

In some embodiments, the light source unit is selected from a pulsed laser or a continuous laser. The embodiment of the invention can flexibly select the light source unit of the incident light source, and in some specific embodiments, the light source unit can be selected from a pulse laser or a continuous laser.

As shown in fig. 1, in some embodiments, an upconversion laser includes: excitation light source @ lambda₁An up-conversion excitation unit and a lens for processing excitation light source, wherein the up-conversion excitation unit comprises total reflection mirrors R arranged oppositely₂And a non-total reflection mirror R₁And an up-conversion unit arranged in the middle, wherein the up-conversion unit comprises an up-conversion material, the length of the excitation cavity is l, the width of the excitation cavity is d, and the height of the excitation cavity is h. Excitation light source lambda₁Non-total reflection mirror R for up-conversion of excitation unit after treatment of incident light source by cylindrical lens or the like₁One side is incident on the up-conversion unit and passes through the total reflection mirror R₂And a non-total reflection mirror R₁The incident light is reflected and gathered, the absorption and conversion of the up-conversion material in the cavity to the optics are improved, and after the light with long wavelength and low energy is converted into the light with short wavelength and high energy by the up-conversion material, the light with short wavelength and high energy is emitted from the side surface of the laser along the direction parallel to the reflector in the optical cavity, so that the laser emission efficiency is improved, and the light source overflow loss is reduced. In some embodiments, total reflection mirrors may be disposed at upper and lower sides of an upconversion excitation unit of the upconversion laser as shown in fig. 1, so that the emitted laser light is emitted fromEmitting from the left side and the right side; or the left and right sides of the upper conversion excitation unit are provided with total reflection mirrors so that the emitted laser is emitted from the upper and lower sides; or the total reflection mirrors are arranged on the upper side and the lower side and the left side or the right side, or the three side surfaces of the left side and the right side and the upper side or the lower side, so that the laser is emitted from a certain side. The total reflection mirrors are arranged on other side edges, so that the emitting direction of the emitted laser is controlled, and the emitted laser is more concentrated.

In order to make the above implementation details and operations of the present invention clearly understood by those skilled in the art, and to make the advanced performance of the upconversion excitation unit and the laser device obvious in the embodiments of the present invention, the above technical solutions are illustrated by the following embodiments.

Example 1

An upconversion laser comprising: the device comprises a total reflecting mirror with the refractive index of 100 percent, a non-total reflecting mirror with the refractive index of 95 percent and an up-conversion unit arranged between the total reflecting mirror and the non-total reflecting mirror, wherein the total reflecting mirror and the non-total reflecting mirror are arranged oppositely; the upconversion unit comprises 40SiO₂-13Al₂O₃-10Na₂CO₃-20BaF₂-4LaF₃A glass carrier and an upconversion material distributed in the glass carrier, wherein the upconversion material comprises Ba₂LaF₇Nanocrystalline carrier and Yb doped in the nanocrystalline carrier³⁺And Tm³⁺Rare earth; the upconverting material was precipitated by annealing at 680 c for 1 hour. Wherein, compared with Ba₂LaF₇，Yb³⁺And Tm³⁺Doping percentage (compared to Ba)₂LaF₇) Respectively 90% and 3%. The up-conversion excitation unit is a cuboid, and the vertical distance between two opposite side surfaces of the total reflection mirror and the non-total reflection mirror is changed from more than 0 cm to 4 cm; the incident light excitation light source is a pulse laser light source and enters the up-conversion excitation unit from the surface of one side, which is perpendicular to the non-total reflection mirror and far away from the up-conversion unit.

Example 2

An upconversion laser comprising: a total reflection mirror with a refractive index of 100% and a non-total reflection mirror with a refractive index of 95% arranged oppositely, and an upper rotation arranged between the total reflection mirror and the non-total reflection mirrorReplacing a unit; the upconversion unit comprises 40SiO₂-13Al₂O₃-10Na₂CO₃-20BaF₂-4LaF₃A glass carrier and an upconversion material distributed in the glass carrier, wherein the upconversion material comprises Ba₂LaF₇Nanocrystalline carrier and Yb doped in the nanocrystalline carrier³⁺And Tm³⁺Rare earth; the upconverting material was precipitated by annealing at 670 ℃ for 1 hour. Wherein, compared with Ba₂LaF₇，Yb³⁺And Tm³⁺Doping percentage (compared to Ba)₂LaF₇) Respectively 90% and 3%. The up-conversion excitation unit is a cuboid, and the vertical distance between two opposite side surfaces of the total reflection mirror and the non-total reflection mirror is changed from more than 0 cm to 4 cm; the incident light excitation light source is a pulse laser light source and enters the up-conversion excitation unit from the surface of one side, which is perpendicular to the non-total reflection mirror and far away from the up-conversion unit.

Example 3

An upconversion laser comprising: the device comprises a total reflecting mirror with the refractive index of 100 percent, a non-total reflecting mirror with the refractive index of 95 percent and an up-conversion unit arranged between the total reflecting mirror and the non-total reflecting mirror, wherein the total reflecting mirror and the non-total reflecting mirror are arranged oppositely; the upconversion unit comprises 40SiO₂-13Al₂O₃-10Na₂CO₃-20BaF₂-4LaF₃A glass carrier and an upconversion material distributed in the glass carrier, wherein the upconversion material comprises Ba₂LaF₇Nanocrystalline carrier and Yb doped in the nanocrystalline carrier³⁺And Tm³⁺Rare earth; the upconverting material was precipitated by annealing at 660 ℃ for 1 hour. Wherein, compared with Ba₂LaF₇，Yb³⁺And Tm³⁺Doping percentage (compared to Ba)₂LaF₇) Respectively 90% and 3%. The up-conversion excitation unit is a cuboid, and the vertical distance between two opposite side surfaces of the total reflection mirror and the non-total reflection mirror is changed from more than 0 cm to 4 cm; the incident light excitation light source is a pulse laser light source and enters the up-conversion excitation unit from the surface of one side, which is perpendicular to the non-total reflection mirror and far away from the up-conversion unit.

Comparative example 1

An upconversion laser comprising: an up-conversion unit; the upconversion unit comprises 40SiO₂-13Al₂O₃-10Na₂CO₃-20BaF₂-4LaF₃A glass carrier and an upconversion material distributed in the glass carrier, wherein the upconversion material comprises Ba₂LaF₇Nanocrystalline carrier and Yb doped in the nanocrystalline carrier³⁺And Tm³⁺Rare earth; the upconverting material was precipitated by annealing at 680 c for 1 hour. Wherein, compared with Ba₂LaF₇，Yb³⁺And Tm³⁺Doping percentage (compared to Ba)₂LaF₇) Respectively 90% and 3%. The incident light excitation light source is a pulse laser light source and enters the up-conversion unit in a vertical mode.

Comparative example 2

An upconversion laser comprising: an up-conversion unit; the upconversion unit comprises 40SiO₂-13Al₂O₃-10Na₂CO₃-20BaF₂-4LaF₃A glass carrier and an upconversion material distributed in the glass carrier, wherein the upconversion material comprises Ba₂LaF₇Nanocrystalline carrier and Yb doped in the nanocrystalline carrier³⁺And Tm³⁺Rare earth; the upconverting material was precipitated by annealing at 670 ℃ for 1 hour. Wherein, compared with Ba₂LaF₇，Yb³⁺And Tm³⁺Doping percentage (compared to Ba)₂LaF₇) Respectively 90% and 3%. The incident light excitation light source is a pulse laser light source and enters the up-conversion unit in a vertical mode.

Comparative example 3

An upconversion laser comprising: an up-conversion unit; the upconversion unit comprises 40SiO₂-13Al₂O₃-10Na₂CO₃-20BaF₂-4LaF₃A glass carrier and an upconversion material distributed in the glass carrier, wherein the upconversion material comprises Ba₂LaF₇Nanocrystalline carrier and Yb doped in the nanocrystalline carrier³⁺And Tm³⁺Rare earth; the upconverting material was precipitated by annealing at 660 ℃ for 1 hour. Therein, compared withBa₂LaF₇，Yb³⁺And Tm³⁺Doping percentage (compared to Ba)₂LaF₇) Respectively 90% and 3%. The incident light excitation light source is a pulse laser light source and enters the up-conversion unit in a vertical mode.

Further, in order to verify the advancement of the upconversion lasers in the embodiments 1 to 3 and the comparative examples 1 to 3 of the present invention, the embodiments of the present invention were subjected to performance tests.

Test example 1

In the test example, the best laser efficiency of examples 1 to 3 and comparative examples 1 to 3 was measured by an integrating sphere, and the test results are shown in the following table 1:

TABLE 1

According to the test results, the laser efficiency of the upconversion lasers in the embodiments 1 to 3 is improved by about 40% compared with the laser efficiency of the upconversion lasers in the comparative examples 1 to 3 provided with the reflector, and the laser emission efficiency of the laser is remarkably improved.

Test example 2

In the test example, simulation calculation is performed on the variation relationship between the excitation absorption efficiency of the laser in the embodiments 1 to 3 and the cavity length (the relative vertical distance between the total reflection mirror and the non-total reflection mirror) of the upconversion excitation unit through optical simulation, and the calculation result is shown in fig. 2 (the abscissa is the cavity length, and the ordinate is the excitation absorption efficiency). When the cavity length is increased to 3 cm, the excitation absorption efficiency α is substantially stable and slightly decreases, and therefore, the cavity length of the laser is preferably set to 3 mm to 3 cm. Specifically, such as: example 1 theoretical laser absorption efficiency of gain cavity was 4.2cm^-1When the cavity length is 0.35cm, the excitation absorption efficiency is improved by nearly 40%; example 2 theoretical laser absorption efficiency of a gain cavity is2cm^-1When the cavity length is 0.6cm, the excitation absorption efficiency is improved by nearly 35%; example 3 theoretical laser absorption efficiency of gain cavity is 0.5cm^-1When the cavity length is 2.5cm, the excitation absorption efficiency is improved by nearly 35%.

In addition, the laser threshold of the laser of example 1 and the laser of comparative example 1 were also tested by the integrating sphere, and the test results are shown in table 2 below:

TABLE 2

	Laser threshold (mJ/cm)2)
		Comparative example 1	120
Example 1	80

From the test results, the laser threshold of the laser with the front and rear reflectors added in embodiment 1 of the present invention is reduced by 40% compared with the laser threshold of the laser without the reflectors added in proportion 1, which indicates that the laser in embodiment 1 of the present invention has lower laser emission power and is easier to emit laser.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.