CN216355285U - Micro-lens coupling laser of LD pump - Google Patents

Abstract

The utility model provides a micro-lens coupling laser of an LD pump, which comprises an LD pump source, a bonding crystal and a micro-lens system positioned between the bonding crystal and the pump source, wherein the LD pump source is used for emitting pump light with preset wavelength; the micro-lens system is positioned at one side close to the LD pumping source and used for carrying out beam shaping on the pumping light with the preset wavelength according to a selected bonded crystal, and shaping the beam into a preset shape, wherein the bonded crystal is Nd: YAG/Cr: YAG composite bonded crystal for stimulated emission of laser light. The laser device has the advantages of small volume, difficult loss and better light beam transmission effect.

Description

Micro-lens coupling laser of LD pump

Technical Field

The utility model relates to the field of lasers, in particular to a micro-lens coupling laser of an LD pump.

Background

The laser of Laser Diode (LD) pump laser gain medium has the advantages of wide pump absorption bandwidth, large absorption coefficient, large stimulated emission cross section and the like, and has attracted great attention in recent years. Especially lasers that pump bonded crystals by LD are more common. However, the pump source and the bonding crystal of the laser are generally coupled by an optical fiber, which is fragile, bulky, not easy to use and maintain, and inconvenient to miniaturize and integrate the system.

Disclosure of Invention

In order to solve the above problems, the present invention provides a microlens coupled laser of LD pumping.

An LD pumped microlens coupled laser, comprising an LD pump source, a bonding crystal, a microlens system between the bonding crystal and the pump source,

the LD pumping source is used for emitting pumping light with a preset wavelength;

and the micro lens system is positioned at one side close to the LD pumping source and is used for carrying out beam shaping on the pumping light with the preset wavelength according to the selected bonding crystal and shaping the beam into a preset shape.

The bonded crystal is Nd: YAG/Cr: YAG composite bonded crystal for stimulated emission of laser light.

Preferably, the micro lens system is FAC, SAC, FAC, BTS, FAC, SAC, BTS, or BTS disposed along the optical path direction.

Preferably, the beam divergence angle after the FAC is less than 10 mrad.

Preferably, the focal length of the FAC is 0.9 mm.

Preferably, the beam divergence angle after the SAC is less than 65 mrad.

Preferably, the spot size after the beam shaping is 0.8 mm.

Preferably, the LD pump source emits pump light with a wavelength of 808 nm.

Preferably, the size of the bonded crystal is 3mmx3mmxL, wherein L is within the range of 1mm < L < 10 mm.

By adopting the laser, the LD pumping source and the crystal are coupled through the micro-lens system, the laser has small volume, convenient use and adjustment, system integration and miniaturization, and the micro-lens system has stable state, is not easy to lose and has better light beam transmission effect. Meanwhile, a micro lens system formed by combining FAC, SAC, BTS and the like can adjust and shape light beams according to used bonding crystals, and a laser can output better target laser. Furthermore, the bonded crystal is used in the utility model, so that the thermal effect can be reduced, and the structure of the resonant cavity is more compact.

Drawings

FIG. 1 is a schematic diagram of a laser according to the present invention;

FIG. 2 is a schematic diagram of a bonded crystal structure;

fig. 3(a), 3(b), 3(c) and 3(d) are schematic structural views of the microlens system.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings in conjunction with the following detailed description. It should be understood that the description is intended to be exemplary only, and is not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

In the drawing there is shown a schematic diagram of the structure of a laser according to an embodiment of the utility model. The figures are not drawn to scale, wherein certain details are exaggerated and possibly omitted for clarity. The shapes of various regions, layers, and relative sizes and positional relationships therebetween shown in the drawings are merely exemplary, and deviations may occur in practice due to manufacturing tolerances or technical limitations, and a person skilled in the art may additionally design regions/layers having different shapes, sizes, relative positions, as actually required.

The utility model provides an LD pumped micro-lens coupled laser, as shown in FIG. 1, comprising an LD pumping source 11, a bonding crystal 12, and a micro-lens system 13 between the LD pumping source and the bonding crystal. In this embodiment, the LD pump source 11 sets a preset wavelength according to a preselected bonding crystal, and preferably, in this embodiment, the preset wavelength is 808nm, and is used for pumping Nd: YAG + Cr is a YAG composite bonded crystal which can be matched with the absorption peak of the bonded crystal so as to output laser with target wavelength; the bonded crystal can effectively reduce the length of a resonant cavity where the bonded crystal is located, and the resonant cavity efficiency is improved.

Further, as shown in fig. 2, two side surfaces of the bonding crystal 12 are respectively bonded with an undoped crystal so as to improve the thermal conductivity of the crystal, where the two side surfaces are respectively a front side surface close to the LD pump source 11 and a rear side surface far from the LD pump source 11, the undoped crystal bonded with the front side surface is a first undoped crystal, and the undoped crystal bonded with the rear side surface is a second undoped crystal. In this embodiment, the undoped crystal is a YAG crystal, and the gain medium and the undoped crystal of the same host material are bonded together, so that the stress on the front side and the back side of the bonded crystal can be further reduced, the thermal effect of the laser can be effectively improved, and the resonant cavity can be more compact.

The bonding crystal 12 and the first end face and the second end face of the bonding crystal 12 constitute a resonant cavity as a mirror face of the resonant cavity, the first end face is plated with a film with high reflection to light with a wavelength of 1064nm and high transmission to light with a wavelength range of 808nm-880nm, the second end face is plated with a film with 40% transmittance to light with a wavelength of 1064nm, wherein the first end face is a face of the first undoped crystal close to the LD pump source 11, and the second end face is a face of the second undoped crystal far away from the LD pump source 11.

Further, in order to better realize beam shaping by the micro lens system 13 and generate light with a better target wavelength, the size of the bonding crystal 12 in the embodiment is 3mmx3mmxL, where L is the length of the bonding crystal 12, and preferably, L is greater than or equal to 1mm and less than or equal to 10 mm.

The micro lens system 13 is located at a side close to the LD pump source 11, preferably, is attached to an end surface of the LD pump source 11, and is configured to shape the light beam emitted by the LD pump source 11 into a predetermined shape, so that the light intensity distribution passing through the micro lens system is uniform, and preferably, when the size of the light spot is 0.8mm, the shaping effect is good.

Specifically, the microlens system 13 is a Fast Axis Collimator (FAC) disposed along the optical path direction, as shown in fig. 3(a), or a FAC and a Slow Axis Collimator (SAC) shown in fig. 3(b), or a FAC and a beam converter (BTS) shown in fig. 3(c), or a FAC, a SAC and a BTS shown in fig. 3 (d).

The divergence angle of the pump light is smaller than 10mrad after passing through the FAC, the divergence angle of the pump light is smaller than 65mrad after passing through the SAC, the BTS is determined according to the FAC and SAC specifications, and preferably, when the focal length of the FAC is 0.09mm, the shaping effect is better.

It is to be understood that the above-described embodiments of the present invention are merely illustrative of or explaining the principles of the utility model and are not to be construed as limiting the utility model. Therefore, any modification, equivalent replacement, improvement and the like made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. Further, it is intended that the appended claims cover all such variations and modifications as fall within the scope and boundaries of the appended claims or the equivalents of such scope and boundaries.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the utility model.

Claims (7)

1. An LD pumped microlens coupled laser, characterized in that the laser comprises an LD pump source, a bonding crystal, and a microlens system between the bonding crystal and the pump source, wherein,

the LD pumping source is used for emitting pumping light with a preset wavelength;

the micro lens system is positioned at one side close to the LD pumping source and is used for carrying out beam shaping on the pumping light with the preset wavelength according to the selected bonding crystal and shaping the beam to a preset shape, the micro lens system is FAC, or FAC, SAC, or FAC, BTS, or FAC, SAC, BTS,

the bonded crystal is Nd: YAG + Cr: the YAG composite bonding crystal is used for stimulating and emitting target laser, the first end surface of the bonding crystal is plated with a film which is highly reflective to light with a wavelength of 1064nm and highly transparent to light with a wavelength range of 808nm-880nm, and the second end surface of the bonding crystal is plated with a film which has 40% transmittance to light with a wavelength of 1064 nm.

2. The laser of claim 1, wherein a beam divergence angle after passing through the FAC is less than 10 mrad.

3. The laser of claim 2, wherein the focal length of the FAC is 0.9 mm.

4. The laser of claim 1, wherein a beam divergence angle after passing over the SAC is less than 65 mrad.

5. The laser according to any of claims 1 to 2, wherein the spot size after said beam shaping is 0.8 mm.

6. The laser of claim 1, wherein the LD pump source emits pump light with a wavelength of 808 nm.

7. The laser of claim 1 or 6, wherein the bonded crystal has a size of 3mmx3mmxL, wherein L is in the range of 1mm ≦ L ≦ 10 mm.

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