SUMMERY OF THE UTILITY MODEL
In view of the above, it is desirable to provide a 266nm pulse solid-state laser with compact structure, high frequency doubling efficiency and long service life.
In order to solve the problems, the utility model adopts the following technical scheme:
a 266nm pulsed solid state laser comprising: the Laser Diode (LD) laser comprises an LD pumping source (1), a four-section type bonding crystal (2), a focusing lens (3), an LBO crystal (4), a collimating lens (5), a dichroic mirror (7), a two-dimensional translation stage (8), a CLB0 crystal (9), a high-temperature constant temperature furnace (10) and a beam splitter prism (11), wherein the high-temperature constant temperature furnace (10) is arranged on the two-dimensional translation stage (8), and the CLBO crystal (9) is arranged in the high-temperature constant temperature furnace (10), wherein:
808nm laser emitted by the LD pumping source (1) passes through the four-section type bonding crystal (2), the four-section type bonding crystal (2) absorbs 808nm pump light to form population inversion, laser oscillation is carried out under the feedback and modulation effects of the front end surface and the rear end surface of the four-section type bonding crystal (2) to output 1064nm picosecond laser, the 1064nm picosecond laser passes through the focusing lens (3), beam waist falls into the LBO crystal (4) and is partially converted into 532nm picosecond laser, the residual 1064nm laser (6) which is not converted into 532nm is reflected by the dichroic mirror (7), the 532nm picosecond laser is collimated by the collimating lens (5) and is transmitted by the dichroic mirror (7) to enter the CLB0 crystal (9), the 532nm picosecond laser partially generates 266nm picosecond laser in the CLB0 crystal (9), and the generated 266nm picosecond laser and the residual 532nm laser which is not converted into 266nm are divided into 266nm beam splitting prism (11) together through the beam splitting prism (11) Two lasers (12) and 532nm laser (13) are used for outputting pure 266nm picosecond laser (12) finally.
In some embodiments, the LD pump source (1) adopts a single-tube spatial coupling output, and shapes the beam at the light exit of the laser chip with an optical fiber to form a beam divergence angle 1 in the fast-slow axis direction: 1 output.
In some of these embodiments, the four-segment bonded crystal (2) is YAG/Nd: YAG/Cr4+YAG/YAG with size of phi 3-8 mm, wherein YAG, Nd, YAG, Cr4+YAG and YAG have a diameter of 3mm and lengths of 1, 4, 2 and 1mm respectively.
In some embodiments, the front end face of the four-segment bonded crystal (2) is coated with a 1064nmHR film, the reflectivity to 1064nm is greater than 99.9%, the four-segment bonded crystal is used as a front end mirror of a laser resonant cavity, the rear end face of the four-segment bonded crystal is coated with a 1064nmPR film, the reflectivity to 1064nm is 70-75%, and the four-segment bonded crystal is used as an output mirror of the laser resonant cavity.
In some of these embodiments, the Cr4+YAG has an initial transmittance of 20% and has passive Q-switching effect.
In some of these examples, the LBO crystals (4) were 3 × 8mm3 in size, cut at a cut angle Theta 90 °, Phi 11.2 °, with AR @1064&532nm films applied to both ends.
In some of these embodiments, the dichroic mirror (7) is at 45 ° incidence, coated with films of HR @1064nm and AR @532nm, with a reflectivity of greater than 99.5% at 1064nm and a transmission of greater than 95% at 532 nm.
In some of these embodiments, the CLB0 crystals (9) have a length, width, and height dimension of 7 × 5 × 2mm3, a cutting angle of theta62 °, phi45 °.
By adopting the technical scheme, the utility model has the following technical effects:
the 266nm pulse solid laser provided by the utility model has no pump coupling system, small volume and simple structure; a four-section type bonded crystal passive Q-switching mode is adopted to output picosecond pulse width fundamental frequency light, and then picosecond 266nm laser can be output; the frequency doubling conversion efficiency can be improved by adopting a mode of focusing 1064nm laser for frequency doubling and collimating 532nm laser for frequency quadrupling; the quadruple frequency crystal adopts a non-critical phase matching high-temperature working mode to greatly improve the quality of a 266nm laser beam and effectively prevent the CLBO crystal from deliquescing; the quadruple frequency crystal shift design can effectively prolong the service life of the laser.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the utility model and are not to be construed as limiting the utility model.
In the description of the present invention, it is to be understood that the terms "upper", "lower", "horizontal", "inside", "outside", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the 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.
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments.
Referring to fig. 1, a schematic structural diagram of a 266nm pulse solid-state laser according to an embodiment of the present invention includes: the device comprises an LD pumping source (1), a four-section type bonding crystal (2), a focusing lens (3), an LBO crystal (4), a collimating lens (5), a dichroic mirror (7), a two-dimensional translation stage (8), a CLB0 crystal (9), a high-temperature constant temperature furnace (10) and a light splitting prism (11), wherein the high-temperature constant temperature furnace (10) is arranged on the two-dimensional translation stage (8), and the CLBO crystal (9) is arranged in the high-temperature constant temperature furnace (10).
In some embodiments, the LD pump source (1) adopts a single-tube spatial coupling output, and shapes the beam at the light exit of the laser chip with an optical fiber to form a beam divergence angle 1 in the fast-slow axis direction: 1 output.
It can be understood that, because the LD pump source (1) adopts single-tube spatial coupling output, the beam is shaped by the optical fiber at the light exit of the laser chip to form the beam divergence angle 1 in the fast-slow axis direction: 1 output, small divergence angle, and pumping the four-section type bonding crystal (2) to generate 1064nm picosecond laser by only depending on the light outlet of the LD pumping source (1) without a pumping coupling system.
In some of these embodiments, the four-segment bonded crystal (2) is YAG/Nd: YAG/Cr4+: YAG/YAG, with dimensions Φ 3 x 8mm, wherein YAG, Nd: YAG, Cr4+: YAG, YAG are all 3mm in diameter and 1, 4, 2, 1mm in length, respectively.
In some embodiments, the front end face of the four-segment bonded crystal (2) is coated with a 1064nmHR film, the reflectivity to 1064nm is greater than 99.9%, the four-segment bonded crystal is used as a front end mirror of a laser resonant cavity, the rear end face of the four-segment bonded crystal is coated with a 1064nmPR film, the reflectivity to 1064nm is 70-75%, and the four-segment bonded crystal is used as an output mirror of the laser resonant cavity.
In some of these embodiments, the Cr4+YAG has an initial transmittance of 20% and has passive Q-switching effect.
The laser crystal adopts a four-section type bonding design, and the white YAG crystals at the forefront and the last section of the four-section type bonding crystal 2 can weaken the thermal lens effect in the second section of Nd, namely the YAG crystal, reduce the thermal stress and ensure the 1064nm fundamental frequency light output with high power and high beam quality; in addition, two end faces of the four-section type bonding crystal 2 are used as cavity mirrors of the laser resonant cavity, and the laser resonant cavity is long, short, stable and reliable.
In some of these examples, the LBO crystals (4) were 3 × 8mm3 in size, cut at a cut angle Theta 90 °, Phi 11.2 °, with AR @1064&532nm films applied to both ends.
In some of these examples, the LBO crystals (4) were 3 × 8mm3 in size, cut at a cut angle Theta 90 °, Phi 11.2 °, with AR @1064&532nm films applied to both ends.
In some of these embodiments, the CLB0 crystals (9) have a length, width, and height dimension of 7 × 5 × 2mm3, a cutting angle of theta62 °, phi45 °.
It can be understood that the acceptance angle is large when the LBO crystal (4) is subjected to frequency doubling, the acceptance angle is small when the CLB0 crystal (9) is subjected to frequency doubling, and the frequency doubling efficiency can be effectively improved by adopting a mode that a focused light beam enters the LBO crystal (4) and a collimated light beam enters the CLBO crystal (9).
Furthermore, the CLBO crystal (9) is placed in a high-temperature constant-temperature furnace (10), the CLBO crystal (9) adopts a high-temperature zero-walk-off-angle phase matching technology, the cutting angle is theta62 degrees and phi45 degrees, fundamental frequency light and frequency doubling light are overlapped and are not separated, higher frequency doubling efficiency can be realized, and meanwhile, the beam quality of the four-frequency-doubled 266nm picosecond laser is better.
In addition, the single-point life of the CLBO crystal (9) is short, and after the single-point life of the CLBO crystal (9) is over, the point of the CLBO crystal (9) is shifted along the length direction of the CLBO crystal (9) through the two-dimensional translation stage (8), and the point is shifted by one point every 1.5mm, so that the service life of the laser can be greatly prolonged.
The operation of the 266nm pulse solid-state laser provided in this embodiment is described in detail below:
808nm laser emitted by the LD pumping source (1) passes through the four-section type bonding crystal (2), the four-section type bonding crystal (2) absorbs 808nm pump light to form population inversion, and Cr are respectively arranged on the front end surface and the rear end surface of the four-section type bonding crystal (2)4+Under the modulation of YAG, laser oscillation outputs 1064nm picosecond laser, the 1064nm picosecond laser passes through the focusing lens (3), falls into the LBO crystal (4) through the beam waist and is partially converted into 532nm picosecond laser, the residual 1064nm laser (6) which is not converted into 532nm is reflected by the dichroic mirror (7), the 532nm picosecond laser is collimated by the collimating lens (5) and transmits the dichroic mirror (7) to enter the CLB0 crystal (9), the 532nm picosecond laser partially generates 266nm picosecond laser in the CLB0 crystal (9), and the generated 266nm picosecond laser is 266nm picosecond laserThe light and residual 532nm laser light which is not converted into 266nm are divided into two laser light beams of 266nm laser light (12) and 532nm laser light (13) through the beam splitter prism (11), and finally pure 266nm picosecond laser light (12) is output.
The 266nm pulse solid laser provided by the utility model has no pump coupling system, small volume and simple structure; a four-section type bonded crystal passive Q-switching mode is adopted to output picosecond pulse width fundamental frequency light, and then picosecond 266nm laser can be output; the frequency doubling conversion efficiency can be improved by adopting a mode of focusing 1064nm laser for frequency doubling and collimating 532nm laser for frequency quadrupling; the quadruple frequency crystal adopts a non-critical phase matching high-temperature working mode to greatly improve the quality of a 266nm laser beam and effectively prevent the CLBO crystal from deliquescing; the quadruple frequency crystal shift design can effectively prolong the service life of the laser.
The foregoing is considered as illustrative only of the preferred embodiments of the utility model, and is presented merely for purposes of illustration and description of the principles of the utility model and is not intended to limit the scope of the utility model in any way. Any modifications, equivalents and improvements made within the spirit and principles of the utility model and other embodiments of the utility model without the creative effort of those skilled in the art are included in the protection scope of the utility model based on the explanation here.