Use of class of quaternary molybdenum/tungsten tellurate crystals, and device

Abstract

The present disclosure relates to use of a quaternary molybdenum/tungsten tellurite crystal and a device thereof. The quaternary molybdenum/tungsten tellurite crystal is used as an acousto-optic material, wherein the quaternary molybdenum/tungsten tellurite comprises tellurium (Te) and tungsten (W), or tellurium (Te) and molybdenum (Mo). The crystal has abundant kinds, is non-toxic, and includes high, medium and low symmetry crystal systems; it easily produces a large-size and high-quality single crystal and almost meets all requirements of excellent acousto-optic properties. In the present disclosure, by selecting different light transmission directions and excitation source directions to fabricate an acousto-optic device with practical application values according to the requirements of the crystal acousto-optic device and the crystal characteristics, high-performance acousto-optic Q switching laser output is achieved.

Claims

1. Use of quaternary molybdenum/tungsten tellurite crystal as an acousto-optic material wherein the quaternary molybdenum/tungsten tellurite is a tetraoxide comprising tellurium (Te) and tungsten (W), or tellurium (Te) and molybdenum (Mo), wherein the quaternary molybdenum/tungsten tellurite crystal is used as an acousto-optic medium to fabricate an acousto-optic device.

2. The use according to claim 1, wherein the acousto-optic device comprises an acousto-optic modulator, an acousto-optic deflector, and an acousto-optic filter.

3. The Use according to claim 1, wherein the quaternary molybdenum/tungsten tellurite is -BaTeMo.sub.2O.sub.9, -BaTeMo.sub.2O.sub.9, Cs.sub.2TeMo.sub.3O.sub.12, Cs.sub.2TeW.sub.3O.sub.12, Na.sub.2TeW.sub.2O.sub.9, or CdTeMo.sub.6.

4. An acousto-optic device, comprising an acousto-optic medium, a piezoelectric transducer and an impedance matching network, wherein a quaternary molybdenum/tungsten tellurite crystal serves as the acousto-optic medium, wherein the quaternary molybdenum/tungsten tellurite is a tetraoxide comprising tellurium (Te) and tungsten (W), or tellurium (Te) and molybdenum (Mo).

5. The acousto-optic device according to claim 4, wherein the quaternary molybdenum/tungsten tellurite is -BaTeMo.sub.2O.sub.9, -BaTeMo.sub.2O.sub.9, Cs.sub.2TeMo.sub.3O.sub.12, Cs.sub.2TeW.sub.3O.sub.12, Na.sub.2TeW.sub.2O.sub.9, or CdTeMo.sub.6.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram of diffraction of an acousto-optic provided by the present disclosure.

(2) FIG. 2 is a Q switching optical path diagram of an acousto-optic device according to Embodiments 1-6 of the present disclosure, in which 1: pumping source, 2: focusing system, 3: input mirror, 4: laser crystal, 5: acousto-optic modulator, and 6: output mirror.

(3) FIG. 3 is a Q switching laser output display diagram according to Embodiment 1 of the present disclosure.

(4) FIG. 4 is a Q switching laser output display diagram according to Embodiment 2 of the present disclosure.

(5) FIG. 5 is a Q switching laser output display diagram according to Embodiment 3 of the present disclosure.

(6) FIG. 6 is a Q switching laser output display diagram according to Embodiment 4 of the present disclosure.

(7) FIG. 7 is a Q switching laser output display diagram according to Embodiment 5 of the present disclosure.

(8) FIG. 8 is a Q switching laser output display diagram according to Embodiment 6 of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

(9) The present disclosure will be described in detail below in conjunction with the embodiments and the drawings, but is not limited thereto.

(10) Crystals described in the embodiments are all prepared according to the prior art.

(11) Particularly, -BaTeMo.sub.2O.sub.9 crystal is prepared with reference to the Chinese patent CN102031563A; -BaTeMo.sub.2O.sub.9 crystal is prepared with reference to the Chinese patent CN1958883A; Cs.sub.2TeMo.sub.3O.sub.12 crystal is prepared with reference to the Chinese patent CN102011189A; Cs.sub.2TeW.sub.3O.sub.12 crystal is prepared with reference to the Chinese patent CN104562204A; and Na.sub.2TeW.sub.2O.sub.9 crystal is prepared with reference to Cryst. Growth Des. 10 (9), 4091-4095, 2010.

Embodiment 1: -BaTeMo.SUB.2.O.SUB.9 .Crystal

(12) The -BaTeMo.sub.2O.sub.9 crystal belongs to a biaxial crystal, the orthorhombic system, and mm2 point group. The crystal has a light transmissive range of 0.38-5.53 m and a transmittance of about 80%. The transmittance of the crystal after being coated is up to 99% above. The crystal displays a higher refractive index (n.sub.z=2.42@0.4 m). The -BaTeMo.sub.2O.sub.9 crystal has excellent physicochemical properties such as ease of growing large-size and high-quality single crystals; resistance to deliquescence and cleavage, moderate hardness (Mohs4.7), ease of machining, and larger optical damage threshold, etc.

(13) The acousto-optic device comprises an acousto-optic medium, a piezoelectric transducer and an impedance matching network. The -BaTeMo.sub.2O.sub.9 crystal is selected as the acousto-optic medium, and choice and optimization is based on the acousto-optic coefficient of the crystal and a light propagation characteristic in the crystal (in the present embodiment, the z-axis is selected as the direction for transmitting light and the x-axis is for applying the piezoelectric transducer). The crystal is polished in the light transmission direction and coated with an optical anti-reflection film @ 1064 nm. The acousto-optic device is encapsulated with an aluminum shell.

(14) The driver comprises a signal generation and power amplification circuit. The working voltage is DC +24V. The power output end outputs a drive power and is connected to an optical modulator device via a high-frequency cable; and a modulation signal is input through an input end.

(15) If the acousto-optic device in this embodiment is applied to laser Q switching, a Q switching optical path diagram of the acousto-optic device is shown in FIG. 2. The Q switching optical path of the acousto-optic device comprises a pumping source 1, a focusing system 2, an input mirror 3, a laser crystal 4 (Nd:YAG), an acousto-optic modulator 5 and an output mirror 6, which are sequentially connected with one another. The acousto-optic medium of the acousto-optic modulator 5 is the -BaTeMo2O9 crystal. The acousto-optic device generates ultrasonic wave through electro-acoustic conversion, causing periodical change of a refractive index of the modulation medium, playing a role of diffraction grating to the incident light, which further causes diffraction loss of the incident light and decrease of the Q value, and consequently, laser oscillation cannot be formed. Under the excitation of an optical pump, upper state-reversed particle beams continuously accumulate till reaching a saturation value; and at this point, abrupt removal of an ultrasonic field will cause immediate loss of the diffraction effect and surging of the Q value in a cavity, and the laser oscillation recovers rapidly, outputting its energy in a giant pulse form, as shown in FIG. 3.

Embodiment 2: -BaTeMo.SUB.2.O.SUB.9 .Crystal

(16) The -BaTeMo.sub.2O.sub.9 crystal belongs to a biaxial crystal, the monoclinic system, and the 2.sup.nd point group. The crystal has a light transmissive range of 0.5-5 m with a transmittance of about 80%. The transmittance of the crystal after being coated is up to 99% above. The crystal displays a higher refractive index (n.sub.z=2.32@0.4 m). Similarly, the -BaTeMo.sub.2O.sub.9 crystal also has excellent physicochemical properties such as ease of growing large-size and high-quality single crystals; resistance to deliquescence and cleavage, moderate hardness (Mohs4.7), ease of machining, and larger optical damage threshold, etc.

(17) The -BaTeMo.sub.2O.sub.9 crystal acousto-optic device is similar to that in Embodiment 1, except that in this embodiment, the crystal orientation selects a crystal refractive index main axis, Z axis, as the light transmission direction of the acousto-optic device, and Y axis for applying the piezoelectric transducer. Likewise, as shown in FIG. 4, laser Q-switching can be output according to the laser optical path shown in FIG. 2.

Embodiment 3: Cs.SUB.2.TeMo.SUB.3.O.SUB.12 .Crystal

(18) The Cs.sub.2TeMo.sub.3O.sub.12 crystal belongs to a uniaxial crystal, the hexagonal crystal system, and the 6.sup.th point group. The crystal has a light transmissive range of 0.43-5.38 m with a transmittance of about 80%. The transmittance of the crystal after being coated is up to 99% above. The crystal displays a higher refractive index (n.sub.e=2.03@0.4 m and n.sub.o=2.23@0.48 m). The Cs.sub.2TeMo.sub.3O.sub.12 crystal has excellent physicochemical properties such as ease of growing large-size and high-quality single crystals; resistance to deliquescence and cleavage, moderate hardness (Mohs4.7), ease of machining, and larger optical damage threshold, etc.

(19) The acousto-optic device of the Cs.sub.2TeMo.sub.3O.sub.12 crystal is similar to that in Embodiment 1. In this embodiment, the crystal refractive index Z axis is selected as a light transmission direction of the crystal, and the refractive index X axis is for applying the transducer. Likewise, as shown in FIG. 5, laser Q-switching can be output according to the laser optical path shown in FIG. 2.

Embodiment 4: Cs.SUB.2.TeW.SUB.3.O.SUB.12 .Crystal

(20) The Cs.sub.2TeW.sub.3O.sub.12 crystal belongs to a uniaxial crystal, the hexagonal crystal system, and the 6.sup.th point group. The crystal has a light transmissive range of 0.41-5.31 m with a transmittance of about 80%. The transmittance of the crystal after being coated is up to 99% above. The crystal has a higher refractive index (n.sub.e=1.98@0.4 m and n.sub.o=2.20@0.48 m). The Cs.sub.2TeW.sub.3O.sub.12 crystal has excellent physicochemical properties such as ease of growing large-size and high-quality single crystals; resistance to deliquescence and cleavage, moderate hardness (Mohs4.5), ease of machining, and larger optical damage threshold, etc.

(21) The structure and properties of the Cs.sub.2TeW.sub.3O.sub.12 crystal are similar to those of the Cs.sub.2TeMo.sub.3O.sub.12 crystal. In this embodiment, a light transmission direction of the crystal is identical with that of the Cs.sub.2TeMo.sub.3O.sub.12 crystal. Likewise, as shown in FIG. 6, laser Q-switching can be output according to the laser optical path shown in FIG. 2.

Embodiment 5: CdTeMoO.SUB.6 .Crystal

(22) The CdTeMoO.sub.6 crystal belongs to a uniaxial crystal, a tetragonal crystal, and 42 m.sup.th point group. The crystal has a light transmissive range of 0.345-5.40 m with a transmittance of about 80%. The transmittance of the crystal after being coated is up to 99% above. The crystal has a higher refractive index. The CdTeMoO.sub.6 crystal has excellent physicochemical properties such as ease of growing large-size and high-quality single crystals; resistance to deliquescence and cleavage, moderate hardness, ease of machining, good thermal stability and chemical stability, and larger optical damage threshold, etc.

(23) The acousto-optic device of the CdTeMoO.sub.6 crystal is similar to that in Embodiment 1. The crystal refractive index Z axis is selected as a light transmission direction of the crystal, and the refractive index X axis is for applying the transducer. Likewise, as shown in FIG. 7, laser Q-switching can be output according to the laser optical path shown in FIG. 2.

Embodiment 6: Na.SUB.2.TeW.SUB.2.O.SUB.9 .Crystal

(24) The Na.sub.2TeW.sub.2O.sub.9 crystal belongs to biaxial crystal system, the monoclinic system, and the m.sup.th point group. The crystal has a light transmissive range of 0.45-5.0 m with a transmittance of about 80%. The transmittance of the crystal after being coated is up to 99% above. The crystal has a higher refractive index, wherein n.sub.z=2.12@0.6 m. The Na.sub.2TeW.sub.2O.sub.9 crystal has excellent physicochemical properties such as ease of growing large-size and high-quality single crystals; resistance to deliquescence and cleavage, moderate hardness, ease of machining, and larger optical damage threshold, etc.

(25) The acousto-optic device of the Na.sub.2TeW.sub.2O.sub.9 crystal is similar to that in Embodiment 1. The crystal refractive index Z axis is selected as a light transmission direction of the crystal, and the refractive index X axis is for applying the transducer. Likewise, as shown in FIG. 8, laser Q-switching can be output according to the laser optical path shown in FIG. 2.

(26) Table 1 shows testing of the properties of the crystals in Embodiments 1-6, conventional fused silica and TeO.sub.2.

(27) TABLE-US-00001 TABLE 1 Length of Transmitted Diffraction Density Wave Angle .sub.B Diffraction Material (g/cm3) (m) ( @1.064 m) Efficiency Fused Silica 2.2 0.2-4.5 <85% TeO2 6.0 0.35-5.0 0.705 75%.sup. -BaTeMo.sub.2O.sub.9 5.372 0.5-5.5 0.716 82% -BaTeMo.sub.2O.sub.9 5.477 0.5-5.0 0.66 75% Cs.sub.2TeMo.sub.3O.sub.12 5.004 0.43-5.38 0.68 70% Cs.sub.2TeW.sub.3O.sub.12 6.544 0.41-5.31 0.69 74% CdTeMoO.sub.6 5.66 0.345-5.4 0.67 73% Na.sub.2TeW.sub.2O.sub.9 6.076 0.45-5.0 0.682 72%

(28) It can be seen from Table 1 that the basic physical characteristics of the crystals provided by the present disclosure are close to the basic physical characteristic of the TeO.sub.2 crystal, wherein the diffraction angle and the diffraction efficiency in the performance parameters of the -BaTeMo.sub.2O.sub.9 crystal acousto-optic device are slightly higher than those of the TeO.sub.2 crystal acousto-optic device.