CN209200369U - A pre-biased electro-optic Q-switched all-solid-state laser based on MgO:LN crystal - Google Patents

Abstract

The utility model discloses an electro-optic Q-switched all-solid-state laser based on MgO:LN crystal pre-bias, which comprises a total reflection mirror (1), an electro-optic crystal (2), a polarizer (3), a laser crystal (4), and an output mirror (5), synchronous delayer (6), signal generator (7); the total reflection mirror (1), electro-optic crystal (2), polarizer (3), laser crystal (4), output mirror (5) Arranged in sequence, the synchronous delayer (6) is connected to the electro-optic crystal (2) and the laser crystal (4), and the signal generator (6) is connected to the synchronous delayer (7). The 1064nm semiconductor laser pumped all-solid-state laser with high energy, narrow pulse width and high repetition frequency of the utility model has better beam quality and longer service life, and has the advantage of compact structure at the same time, and can be applied in medical treatment, industry, In many fields such as the military, the 1064nm semiconductor laser with stable output, narrow pulse width and MW-level peak power is mainly realized through electro-optic Q-switching technology.

Description

A pre-biased electro-optic Q-switched all-solid-state laser based on MgO:LN crystal

technical field

The utility model relates to the field of lasers, in particular to a pre-biased electro-optic Q-switched all-solid-state laser based on MgO:LN crystals.

Background technique

The pressurized electro-optic Q-switched laser with a pulse width of about 10 ns can be obtained by a pressurized electro-optic Q-switched laser that is excited by the gain medium to store energy at the upper level. However, based on LD end-pumping, the efficiency is low and the optical path is relatively complicated. Common electro-optic crystals BBO and KD* P is prone to deliquescence, RTP is more expensive, and LGS has a lower damage threshold, which affects its use.

Utility model content

In order to solve the above-mentioned defects in the prior art, the utility model discloses a pre-biased electro-optic Q-switched all-solid-state laser based on MgO:LN crystal.

The utility model is achieved through the following technical solutions:

A pre-biased electro-optic Q-switched all-solid-state laser based on MgO:LN crystal, comprising a total reflection mirror, an electro-optic crystal, a polarizer, a laser crystal, an output mirror, a synchronous retarder, and a signal generator; the total reflection mirror, an electro-optic crystal , a polarizer, a laser crystal, and an output mirror are sequentially arranged, the synchronous retarder is connected to the electro-optic crystal and the laser crystal, and the signal generator is connected to the synchronous retarder.

Preferably, the total reflection mirror is made of a 1064nm high-transmission film.

Preferably, the electro-optic crystal is a MgO:LN crystal with a size of 7 mm×7 mm×20 mm, two of which are plated with a 1064nm high reflection film.

Preferably, the thickness of the polarizer is 2 mm, the diameter is 20 mm, and the included angle between the normal direction of the mirror surface and the optical axis of the resonant cavity is Brewster's angle of 55.0°-56.0°.

Preferably, the laser crystal is a Nd:YAG crystal rod with a size of φ3 mm×65 mm, and both of its two passes are coated with a 1064nm high-transmittance film.

Preferably, the output mirror is a 40% output mirror.

The beneficial effects of the present utility model are:

High energy, narrow pulse width, high repetition rate 1064nm semiconductor laser pumped all-solid-state laser has better beam quality and longer service life, and has the advantage of compact structure, which can be used in medical, industrial, military, etc. In the field, the 1064nm semiconductor laser with stable output, narrow pulse width and MW level peak power is mainly realized by electro-optic Q-switching technology.

Using LD side-pumped long-sized, highly doped Nd:YAG gain medium, based on MgO:LN crystal pre-bias technology and synchronous delay technology, the maximum average output power at the repetition frequency of 1kHz and 200Hz is respectively 1064nm pulsed laser output of 15.4W and 8.4W, the corresponding pulse width is 21ns and 10ns, the peak-to-peak instability of the pulse width is ±4.75% and ±3.25% respectively, and the factor M2 measured at the repetition frequency of 1kHz is M2x= 4.13, M2y=4.65, the experimental results can provide application reference for laser marking, laser cutting, laser drilling, laser ranging, remote sensing, nonlinear optical frequency conversion and other fields.

Description of drawings

Fig. 1 is the structural representation of the utility model;

In the figure: 1. Total reflection mirror 2. Electro-optic crystal 3. Polarizer 4. Laser crystal 5. Output mirror 6. Synchronous delay device 7. Signal generator.

Detailed ways

In order to make the technical solution of the utility model easier to understand, the utility model will be further described below in conjunction with specific embodiments and accompanying drawings.

As shown in Figure 1, a pre-biased electro-optic Q-switched all-solid-state laser based on MgO:LN crystal includes a total reflection mirror 1, an electro-optic crystal 2, a polarizer 3, a laser crystal 4, an output mirror 5, a synchronous delay 6, Signal generator 7; the total reflection mirror 1, electro-optic crystal 2, polarizer 3, laser crystal 4, and output mirror 5 are arranged in sequence, and the synchronous delayer 6 is connected to the electro-optic crystal 2 and the laser crystal 4, and the signal generation The device 7 is connected to the synchronous delay device 6.

The total reflection mirror 1 is coated with a 1064nm high transmission film (R>99.8%).

The electro-optic crystal 2 is a MgO:LN crystal with a size of 7mm×7mm×20mm, two crystals of lithium niobate (MgO:LN) mixed with magnesium oxide and coated with a 1064nm high reflection film (R>99.8%) While possessing the low transverse half-wave voltage of general non-doped lithium niobate crystal (LN), it can greatly improve its anti-light interference and anti-photorefractive properties, and its light intensity is two orders of magnitude higher than that of general LN crystal; and The pre-bias technology based on MgO:LN crystal, compared with the traditional Nd:YAG gain medium pressurized electro-optic Q-switching technology, saves the λ/4 wave plate, reduces the device loss in the optical path, and thus can improve its Output Power.

The polarizer 3 has a thickness of 2mm and a diameter of 20mm, and the included angle between the normal direction of the mirror surface and the optical axis of the resonant cavity is Brewster's angle of 55.0°-56.0°.

The laser crystal 4 is a Nd:YAG crystal rod with a size of φ3mm×65mm, both of which are plated with a 1064nm high-transmittance film (R>99.8%).

The output mirror 5 is a 40% output mirror.

The principle of the utility model is as follows: the laser power supply is placed in the external control, and the synchronous pulse signal generator provides the trigger pulse signal to the pulse LD pump module drive power supply and the MgO:LN crystal high-voltage drive power supply. By adjusting the delay trigger time of the two signals , to ensure precise synchronization between pressurizing the MgO:LN crystal and triggering the 808nm pulsed LD pump light, so as to achieve the purpose of maximum energy storage in the cavity. Among them, the LD pump module is a side three-way, adjacent LD array with an angle of 120°, the laser gain medium is Nd:YAG crystal rod, the center emission wavelength of pulse LD is 808nm, and the pulse repetition frequency is adjustable from 1kHz to 1Hz. The duty cycle of the pump is 20%, the pulse width is 250μs, and the deflection angle of the MgO:LN crystal along the optical axis is θ=2.96° according to theoretical calculations. Q value, the resonant cavity cannot generate oscillation, and there is no laser output; MgO:LN crystal is applied with voltage, and it is incident at a suitable angle θ along the deviation from the optical axis. After passing through the MgO:LN crystal, the phase difference generated by the outgoing light can be π/2 , its effect is equivalent to the λ/4 wave plate, the resonant cavity generates laser oscillation, with low loss, high Q value, and P-polarized light output in the resonant cavity.

The beneficial effects of this embodiment are: the LD side-pumped long-sized, highly doped Nd:YAG gain medium is adopted, based on the pre-bias technology and synchronous delay technology of MgO:LN crystal, and the repetition frequency of 1kHz and 200Hz is obtained. , the maximum average output power is 15.4W and 8.4W of 1064nm pulsed laser output, the corresponding pulse width is 21ns and 10ns, and the peak-to-peak instability of the pulse width is ±4.75% and ±3.25%, respectively. The measured factor M2 is M2x=4.13, M2y=4.65. The experimental results can provide application reference for laser marking, laser cutting, laser drilling, laser ranging, remote sensing, nonlinear optical frequency conversion and other fields.

The above description is only a preferred example of the utility model, and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the aforementioned embodiments, for those skilled in the art, it can still be used for the aforementioned items. The technical solutions described in the embodiments are modified, or equivalent replacements are made to some of the technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims (6)

1. one kind is based on the electric-optically Q-switched all solid state laser of MgO:LN crystal prebias, which is characterized in that including total reflection mirror, electricity Luminescent crystal, polarizing film, laser crystal, outgoing mirror, synchronization delay device, signal generator；The total reflection mirror, electro-optic crystal, partially Vibration piece, laser crystal, outgoing mirror are set gradually, and the synchronization delay device is connected to electro-optic crystal and laser crystal, the signal Generator is connected to synchronous delayer.

2. all solid state laser according to claim 1, which is characterized in that it is highly transmissive that the total reflection mirror is coated with 1064nm Film.

3. all solid state laser according to claim 1, which is characterized in that the electro-optic crystal is MgO:LN crystal, Having a size of 7mm × 7mm × 20mm, two light passings are coated with 1064nm high-reflecting film.

4. all solid state laser according to claim 1, which is characterized in that the polarizing film with a thickness of 2mm, diameter is 20mm, the angle between mirror normal direction and resonant cavity light passing axis are 55.0 ° -56.0 ° of Brewster's angle.

5. all solid state laser according to claim 1, which is characterized in that the laser crystal is Nd:YAG crystal bar, , having a size of φ 3mm × 65mm, two light passing is coated with the highly transmissive film of 1064nm for it.

6. all solid state laser according to claim 1, which is characterized in that the outgoing mirror is 40% outgoing mirror.