CN203119287U - KTP Q-switching and parameter dual-function device capable of compensating walk-off and static birefringence - Google Patents

Abstract

The utility model relates to a KTP Q-switching and parameter dual-function device capable of compensating walk-off and static birefringence. The KTP Q-switching and parameter dual-function device comprises a shell, electrodes and an electro-optical crystal. The electro-optical crystal comprises four KTP crystals, wherein the four KTP crystals are sequentially arranged from the left side to the right side, the four KTP crystals are low in conductivity and are cut according to an II parameter critical phase matching angle, and the four KTP crystals are arranged by sequentially rotating for 90 degrees. Upper and lower electrifying surfaces of the first KTP crystal and the third KTP crystal are plated with gold films, and front and back electrifying surfaces of the second KTP crystal and the fourth KTP crystal are plated with gold films. Gold wires are led out from the upper electrifying surface of the first crystal, the front electrifying surface of the second crystal, the lower electrifying surface of the third crystal and the back electrifying surface of the fourth crystal, and are connected to the positive electrode; and gold wires are led out from the electrifying surfaces on the other sides of the four crystals and are connected to the negative electrode. The KTP Q-switching and parameter dual-function device achieves an electro-optical Q-switching effect in a voltage decreasing working way. The KTP Q-switching and parameter dual-function device compensates a walk-off angle and a static birefringence phase delay and eliminates the influences on the phase matching angle when the crystals are pressurized, while simultaneously achieving the two functions of parameter effecting and electro-optical Q-switching.

Description

A kind of compensation is walked from the KTP with static birefringent and is transferred Q parameter double-function device

Technical field:

The utility model relates to a kind of electro-optical Q-switch device, is specially a kind ofly can realize electric-optically Q-switched in laser and the device of parameter nonlinear effect takes place simultaneously.

Background technology:

The KTP crystalloid has big effective nonlinear coefficient and good electro-optical properties, therefore utilizes the research of this crystalloid development nonlinear effect and electric light multiplexing device to cause the great interest of people.1994, Japanese T. Takunori etc. were with 1 * a 3 * 5mm ³Ktp crystal, to Nd:YVO ₄The 1064nm laser of output has been realized frequency multiplication and accent Q simultaneously.When repetition rate 100Hz, modulation obtains the 532nm pulse laser output that pulsewidth is 18ns, peak power is 15.4W (Takunori Taira, Takao Kobayashi. Q-switching and frequency doubling of solid-state laser by a single intracavity KTP crystal [J], IEEE. J. Quantum Eleronies, 1994,30 (3): 800-804).Nineteen ninety-five, they have realized green glow output (Takunori Taira, the Takao Kobayashi. Intraeavity frequency doubling and Q-switching in diode laser pumped Nd:YVO of peak power 230W again ₄Laser [J], APPlied Optics 1995,34 (21): 4298-4301).1997, matching angle and applied voltage when Yao Jianquan etc. transfer Q to the ktp crystal frequency multiplication have carried out calculating (J.Q.Yao, X.W.Sun, H.S.Kwok. Analysis of simultaneous Q-switching and frequency doubling in KTP [J], Journal of modern optics, 1997,44 (5): 997-1004).2000, Chen Fei etc. adopted 2 * 4 * 10mm ³Ktp crystal, be 1kHz in repetition rate, λ/4 voltage 647V during pump power 1W, has realized the TEM of pulsewidth 12ns, peak power 762W ₀₀Mould output, and realized device, whole volume has only half colour film size, and (new type electro is transferred Q inner chamber green (light) laser [J], Chinese engineering science, 2000,2 (4): 39-42) for Chen Fei, Huo Yujing.Ktp crystal is used for optical parametric oscillation and electric-optically Q-switched research seldom simultaneously, and Zhang Peng, Zhang Yuping etc. are used for optical parametric oscillation simultaneously and have electric-optically Q-switchedly carried out theoretical calculating ktp crystal, calculate, for 5 * a 5 * 20mm ³Ktp crystal, if obtain the parameteric light of 1.57 μ m, the phase matching angle of KTP should be θ=90 °,

, the half-wave voltage that applies at crystal z axle should be 887V.In the above scheme with KTP as non-linear and electro-optical Q-switch device, all used a ktp crystal, and cut according to the phase matched angle.But because there is static birefringent phase delay in ktp crystal, use the design of a KTP to have influence on the electric-optically Q-switched effect of closing the door; And have deviation angle at parameter as the time spent according to the ktp crystal of the phase matched angle under normal temperature cutting, have influence on the efficient of parameter conversion.

Summary of the invention:

The utility model is at the deficiencies in the prior art, provide a kind of can compensation walk from the electric-optically Q-switched parameter double-function device of the KTP of static birefringent.

The utility model realizes that the scheme that above purpose is taked is: a kind of compensation is walked from the KTP with static birefringent and is transferred Q parameter double-function device, comprise shell, electrode, electrooptic crystal, electrooptic crystal comprises four ktp crystals that satisfy the critical phase matched of II class, from left to right sets gradually first ktp crystal, second ktp crystal that relative first ktp crystal half-twist placed, the 3rd ktp crystal of relative first ktp crystal Rotate 180 ° placement and the 4th ktp crystal of relative the 3rd ktp crystal half-twist placement; The gold-plated film of energising face on first ktp crystal, the gold-plated film of following energising face, the gold-plated film of preceding energising face at second ktp crystal, the gold-plated film of back energising face, the gold-plated film of energising face on the 3rd ktp crystal, the gold-plated film of following energising face is at the gold-plated film of preceding energising face of the 4th ktp crystal, the gold-plated film of back energising face; Draw gold thread from the gold-plated film of following energising face of the gold-plated film of preceding energising face of the gold-plated film of last energising face of first ktp crystal, second ktp crystal, the 3rd ktp crystal and the gold-plated film of back energising face of the 4th ktp crystal, be connected to positive electrode; Draw gold thread from the gold-plated film of last energising face of the gold-plated film of back energising face of the gold-plated film of following energising face of first ktp crystal, second ktp crystal, the 3rd ktp crystal and the gold-plated film of preceding energising face of the 4th ktp crystal, be connected to negative electrode.

As further improvement of the utility model, the 3rd ktp crystal of second ktp crystal that first ktp crystal, relative first ktp crystal half-twist are placed, relative first ktp crystal Rotate 180 ° placement and the 4th ktp crystal that relative the 3rd ktp crystal half-twist placed are the ktp crystal of low conductivity.

As further improvement of the utility model, first second ktp crystal, the 3rd ktp crystal of relative first ktp crystal Rotate 180 ° placement and the 4th critical phase matched of ktp crystal employing II class degeneracy parameter of relative the 3rd ktp crystal half-twist placement that ktp crystal, relative first ktp crystal half-twist are placed, cutting angle is θ=52.3 °

As further improvement of the utility model, first ktp crystal, second ktp crystal of relative first ktp crystal half-twist placement, the 3rd ktp crystal of relative first ktp crystal Rotate 180 ° placement and the logical light face of the 4th ktp crystal that relative the 3rd ktp crystal half-twist placed are square.

As further improvement of the utility model, the 3rd ktp crystal of second ktp crystal that first ktp crystal, relative first ktp crystal half-twist are placed, relative first ktp crystal Rotate 180 ° placement interior logical light face relative with the 4th ktp crystal that relative the 3rd ktp crystal half-twist placed links to each other with the optical cement of insulation transparent, leads to the light face outward and plates 1064nm and the double-colored anti-reflection film of 2128nm.

As further improvement of the utility model, the 3rd ktp crystal of second ktp crystal that first ktp crystal, relative first ktp crystal half-twist are placed, relative first ktp crystal Rotate 180 ° placement placed successively with the 4th ktp crystal that relative the 3rd ktp crystal half-twist placed, interior logical light face and outer logical light face plating 1064nm and the double-colored anti-reflection film of 2128nm.

The utility model realizes that above purpose principle is:

The cutting angle of the critical phase matched of ktp crystal degeneracy II class is θ=52.3 °,

Therefore, the propagation of light wave in the monolithic ktp crystal exists natural birefringence and deviation angle under this kind cutting mode, adopts rotate to an angle method compensation deviation angle and the static phase of serial connection of four identical ktp crystals to postpone.

The phase delay that polarised light produces during by the monolithic ktp crystal is:

$\begin{array}{c}\mathrm{\&Gamma;}=-\frac{2\mathrm{\&pi;}}{\mathrm{\&lambda;}}(n_z^{\&prime;}-n_x^{\&prime;})L\\ =-\frac{2\mathrm{\&pi;}}{\mathrm{\&lambda;}}(n_z-n_x)L+\frac{\mathrm{\&pi;}}{\mathrm{\&lambda;}}{\mathrm{<figure-callout\; id="3"\; label="n\; z"\; filenames="121204184346.png"\; state="\{\{state\}\}">n</figure-callout>}}_z^{}{\mathrm{\&gamma;}}_{c1}{E}_{z}L={\mathrm{\&Gamma;}}_S+{\mathrm{\&Gamma;}}_E\end{array}$

In the following formula, first Γ s is the phase delay that natural birefringence causes, and be irrelevant with extra electric field; Second Γ _EBe the phase delay that is produced by the extra electric field effect.

If at identical ktp crystal that has rotated 90 ° of serial connection, then the phase delay that produces during the ktp crystal of polarised light by being connected in series is this piece ktp crystal after:

$\begin{array}{c}\mathrm{\&Gamma;}=-\frac{2\mathrm{\&pi;}}{\mathrm{\&lambda;}}(n_x^{\&prime;}-n_z^{\&prime;})L\\ =-\frac{2\mathrm{\&pi;}}{\mathrm{\&lambda;}}(n_x-n_z)L+\frac{\mathrm{\&pi;}}{\mathrm{\&lambda;}}{\mathrm{<figure-callout\; id="3"\; label="n\; z"\; filenames="121204184346.png"\; state="\{\{state\}\}">n</figure-callout>}}_z^{}{\mathrm{\&gamma;}}_{c1}{E}_{z}L=-{\mathrm{\&Gamma;}}_S+{\mathrm{\&Gamma;}}_E\end{array}$

At this moment, natural birefringence (n _z-n _x) compensated.Therefore, our designed structure can be good at compensating the natural birefringence of ktp crystal.According to above-mentioned derivation, in twos after the butt joint again the phase delay of four ktp crystals of half-twist serial connection be:

${\mathrm{\&Gamma;}}_E=4\frac{\mathrm{\&pi;}}{\mathrm{\&lambda;}}{n}_z^3{\mathrm{\&gamma;}}_{c1}\frac{V}{d}L$

V is along the added voltage of z direction, can calculate needed half-wave voltage V π thus.In addition, in parallel on series connection, the electricity on four ktp crystal optics, producing the required half-wave voltage of π phase delay is 1/4 of monolithic KTP electro-optical Q-switch.

If logical light face length of side d=4mm, logical light length is L, the d/L value not simultaneously, corresponding half-wave voltage is as shown in the table:

The required half-wave voltage of the different aspect ratios of table one

Realize also need considering the compensation of deviation angle after the compensation of static phase delay.Ktp crystal adopt the critical phase matched of II class degeneracy parameter (θ=52.3 °,

), the cutting of z axle, optical propagation direction is parallel to the y axle.Suppose that parameteric light is by the deviation angle of its direction of propagation of energy behind ktp crystal with fundamental frequency light generation α 1, after this piece crystal, place an other identical ktp crystal, making two angles between the ktp crystal optical axis is 180 °, at this moment, the deviation angle of the parameteric light by second ktp crystal is α 2, it is identical with α 1 size, but is distributed in the complete relative both sides of fundamental frequency optical propagation direction.Therefore, when fundamental frequency light passed through two ktp crystals, parameteric light at first was offset downwards in the 1st parameter crystal, upwards is offset again when the 2nd parameter crystal, has obtained compensation.In the utility model device, first and the 3rd ktp crystal, second and the 4th ktp crystal have been realized the compensation of deviation angle.

The beneficial effects of the utility model:

As parameter and electro-optical Q-switch device, a device has been realized parameter and electric-optically Q-switched two kinds of functions to the utility model simultaneously with KTP, and one two, 34 two pairs of relative half-twists of ktp crystal are placed, and have compensated static birefringent phase delay; ° placement of one three, 24 two pairs of relative Rotate 180s of ktp crystal has compensated deviation angle; The influence to phase matching angle is moved back when pressing working method to eliminate the crystal pressurization in employing.

Description of drawings:

Fig. 1. the device principle schematic diagram that four crystal optical cements connect

Fig. 2. the device principle schematic diagram of four crystal plating anti-reflection film

The drawing explanation:

(1) first ktp crystal;

(2) second ktp crystal placing with respect to first ktp crystal half-twist;

(3) with respect to the 3rd ktp crystal of first ktp crystal Rotate 180 °;

(4) with respect to the 4th ktp crystal of the 3rd ktp crystal half-twist;

The gold-plated film of last energising face of (5) first ktp crystals;

The gold-plated film of following energising face of (6) first ktp crystals;

The gold-plated film of preceding energising face of (7) second ktp crystals;

The gold-plated film of back energising face of (8) second ktp crystals;

The gold-plated film of energising face on (9) the 3rd ktp crystals;

The gold-plated film of following energising face of (10) the 3rd ktp crystals;

The gold-plated film of preceding energising face of (11) the 4th ktp crystals;

The gold-plated film of back energising face of (12) the 4th ktp crystals;

(13) positive electrode;

(14) negative electrode.

Embodiment:

The utility model is described in further detail below in conjunction with drawings and Examples.

Embodiment 1 is referring to Fig. 1, a kind of can compensation walk from the electric-optically Q-switched parameter double-function device of the KTP of static birefringent, comprise shell, electrode, electrooptic crystal, electrooptic crystal comprises four with the ktp crystal of the critical phase matched cutting of II class, from left to right sets gradually first ktp crystal 1, second ktp crystal 2 that relative first ktp crystal 1 half-twist placed, the 3rd ktp crystal 3 of relative first ktp crystal 1 Rotate 180 ° placement and the 4th ktp crystal 4 of relative the 3rd ktp crystal 3 half-twists placement; Four ktp crystals are all realized 2.128 μ m parameter degeneracy phase matched by the critical phase matched of II class, and matching angle is θ=52.3 °, φ=0 °; The gold-plated film 5 of energising face on first ktp crystal 1, the gold-plated film 6 of following energising face, the gold-plated film 7 of preceding energising face at second ktp crystal 2 placing with respect to first ktp crystal 1 half-twist, the gold-plated film 8 of back energising face, at the gold-plated film 9 of switching on respect to the ktp crystal 1 Rotate 180 ° ktp crystal that rotation is placed 3, under the gold-plated film 10 of switching on, the gold-plated film 11 of energising before the 4th ktp crystal of placing with respect to the 3rd ktp crystal 3 half-twists 4, the back gold-plated film 12 of switching on; Draw gold thread from the gold-plated film 10 of following energising face of the gold-plated film 7 of preceding energising face of the gold-plated film 5 of the last energising face of first ktp crystal 1, second ktp crystal 2, the 3rd ktp crystal 3 and the gold-plated film 12 of back energising face of the 4th ktp crystal 4, be connected to positive electrode; Draw gold thread from the gold-plated film 9 of last energising face of the gold-plated film 8 of back energising face of the gold-plated film 6 of the following energising face of first ktp crystal, second ktp crystal, the 3rd ktp crystal and the gold-plated film of preceding energising face of the 4th ktp crystal 11, be connected to negative electrode.

First ktp crystal 1, second ktp crystal 2 of relative first ktp crystal half-twist placement, the 3rd ktp crystal 3 of relative first ktp crystal Rotate 180 ° placement and the 4th ktp crystal 4 that relative the 3rd ktp crystal 3 half-twists are placed are the ktp crystal of low conductivity.

First ktp crystal 1, second ktp crystal 2 of relative first ktp crystal half-twist placement, the 3rd ktp crystal 3 of relative first ktp crystal Rotate 180 ° placement and the logical light face of the 4th ktp crystal 4 that relative the 3rd ktp crystal 3 half-twists are placed are square.

The relative interior logical light face of the 3rd ktp crystal 3 of second ktp crystal 2 that first ktp crystal 1, relative first ktp crystal half-twist are placed, relative first ktp crystal Rotate 180 ° placement and the 4th ktp crystal that relative the 3rd ktp crystal 3 half-twists are placed 4 links to each other with the optical cement of insulation transparent, leads to the light face outward and plates 1064nm and the double-colored anti-reflection film of 2128nm.

Embodiment 2 is substantially the same manner as Example 1, difference is that second ktp crystal 2 that first ktp crystal 1, relative first ktp crystal half-twist place, the 3rd ktp crystal 3 of relative first ktp crystal Rotate 180 ° placement place successively with the 4th ktp crystal 4 that relative the 3rd ktp crystal 3 half-twists are placed, about midfeather 1mm, interior logical light face and outer logical light face all plate 1064nm and the double-colored anti-reflection film of 2128nm.

The utility model transfers Q and parametric device to be used for laser as laser.The parameter nonlinear interaction takes place by ktp crystal in 1064nm laser, and emission 2128nm laser is by the pulse laser of electric-optically Q-switched acquisition high-peak power.Adopt during electric-optically Q-switched work and move back pressure type influence to phase matching angle when eliminating the crystal pressurization.The boundary temperature of crystal is controlled by temperature controlling stove.

Claims (6)

1. a compensation is walked from the KTP with static birefringent to transfer Q parameter double-function device, comprises shell, electrode, electrooptic crystal, it is characterized in that:

Electrooptic crystal comprises four ktp crystals that satisfy the critical phase matched of II class parameter, from left to right sets gradually first ktp crystal (1), second ktp crystal (2) that relative first ktp crystal (1) half-twist is placed, the 3rd ktp crystal (3) of relative first ktp crystal (1) Rotate 180 ° placement and the 4th ktp crystal (4) of relative the 3rd ktp crystal (3) half-twist placement;

The gold-plated film of last energising face (5) at first ktp crystal (1), the gold-plated film of following energising face (6), the gold-plated film of preceding energising face (7) at second ktp crystal (2), the gold-plated film of back energising face (8), the gold-plated film of last energising face (9) at the 3rd ktp crystal (3), the gold-plated film of following energising face (10) is at the gold-plated film of preceding energising face (11) of the 4th ktp crystal (4), the gold-plated film of back energising face (12); Draw gold thread from the gold-plated film of last energising face (5) of first ktp crystal (1), the gold-plated film of preceding energising face (7) of second ktp crystal (2), the gold-plated film of following energising face (10) of the 3rd ktp crystal (3) and the gold-plated film of back energising face (12) of the 4th ktp crystal (4), be connected to positive electrode; Draw gold thread from the gold-plated film of last energising face (9) of the gold-plated film of back energising face (8) of the gold-plated film of following energising face (6) of first ktp crystal, second ktp crystal, the 3rd ktp crystal and the gold-plated film of preceding energising face of the 4th ktp crystal (11), be connected to negative electrode.

2. a kind of compensation according to claim 1 is walked from the KTP with static birefringent and is transferred Q parameter double-function device, it is characterized in that:

The 4th ktp crystal (4) that second ktp crystal (2) of first ktp crystal (1), the placement of relative first ktp crystal (1) half-twist, the 3rd ktp crystal (3) of relative first ktp crystal (1) Rotate 180 ° placement and relative the 3rd ktp crystal (3) half-twist are placed is the ktp crystal of low conductivity.

3. a kind of compensation according to claim 1 is walked from the KTP with static birefringent and is transferred Q parameter double-function device, it is characterized in that:

First ktp crystal (1), second ktp crystal (2) that relative first ktp crystal (1) half-twist is placed, the 4th ktp crystal (4) that the 3rd ktp crystal (3) and relative the 3rd ktp crystal (3) half-twist of ° placement of relative first ktp crystal (1) Rotate 180 are placed adopt the critical phase matched of II class degeneracy parameter, cutting angle is θ=52.3 °

4. a kind of compensation according to claim 1 is walked from the KTP with static birefringent and is transferred Q parameter double-function device, it is characterized in that:

First ktp crystal (1), second ktp crystal (2) that relative first ktp crystal (1) half-twist is placed, the 3rd ktp crystal (3) of relative first ktp crystal (1) Rotate 180 ° placement and the logical light face of the 4th ktp crystal (4) that relative the 3rd ktp crystal (3) half-twist is placed are square.

5. a kind of compensation according to claim 1 is walked from the KTP with static birefringent and is transferred Q parameter double-function device, it is characterized in that:

The relative interior logical light face of the 4th ktp crystal (4) that second ktp crystal (2) that first ktp crystal (1), relative first ktp crystal (1) half-twist are placed, the 3rd ktp crystal (3) of relative first ktp crystal (1) Rotate 180 ° placement and relative the 3rd ktp crystal (3) half-twist are placed links to each other with the optical cement of insulation transparent, leads to the light face outward and plates 1064nm and the double-colored anti-reflection film of 2128nm.

6. a kind of compensation according to claim 1 is walked from the KTP with static birefringent and is transferred Q parameter double-function device, it is characterized in that:

First ktp crystal (1), second ktp crystal (2) that relative first ktp crystal (1) half-twist is placed, the 4th ktp crystal (4) that the 3rd ktp crystal (3) and relative the 3rd ktp crystal (3) half-twist of ° placement of relative first ktp crystal (1) Rotate 180 are placed are placed interior logical light face and outer logical light face plating 1064nm and the double-colored anti-reflection film of 2128nm successively.

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