CN217360461U

CN217360461U - Ultrafast laser broadening compressor based on single transmission grating

Info

Publication number: CN217360461U
Application number: CN202221548221.9U
Authority: CN
Inventors: 王睿; 刘成; 程鑫鑫
Original assignee: Shanghai Ytterbium Radium Femtosecond Laser Technology Co ltd
Current assignee: Shanghai Ytterbium Radium Femtosecond Laser Technology Co ltd
Priority date: 2022-06-20
Filing date: 2022-06-20
Publication date: 2022-09-02
Anticipated expiration: 2032-06-20

Abstract

The application relates to an ultrafast laser widening compressor based on single transmission grating, which is used for widening and compressing ultrafast laser and comprises a body. The inner cavity of the body is provided with a supporting plate, and the upper end of the supporting plate is provided with a first climbing mirror, a grating, a plano-convex lens, a first reflector, a second reflector, a third reflector, a fourth reflector and a hollow right-angle reflector; after the laser passes through the grating through the first climbing mirror, the laser is reflected according to the widening route, the light path is translated for a preset length through the hollow right-angle reflector in the process, the translated light path is reflected according to the original reflection path, and the height of the widened emergent light ray is the same as that of the incident light ray. And then the light enters the cavity again through external amplification treatment, penetrates the grating to the folding mirror through a fifth reflecting mirror and a sixth reflecting mirror arranged in the cavity, is guided into the turn-back mirror through the folding mirror, and is reflected to a second step-up mirror and then is reflected according to the original reflection path. A hollow right-angle reflecting mirror is additionally arranged in the widening process, the light path is translated by utilizing symmetrical imaging of the sagittal plane of the lens, and the widening amount is doubled while the volume of the device is controlled.

Description

Ultrafast laser broadening compressor based on single transmission grating

Technical Field

The application relates to the field of ultrafast lasers, in particular to an ultrafast laser broadening compressor based on a single transmission grating.

Background

In the field of ultrafast laser, the peak power density of laser pulses is a critical parameter of the damage threshold of the optical element, and the higher the peak power density is, the greater the damage of the optical element is. The peak power density is the single pulse energy/(pulse width spot area), and when the single pulse energy and the spot size of the laser are determined, the shorter the time width of the pulse, the higher the peak power density. The chirped pulse amplification technology firstly widens the small-energy ultrashort pulse laser generated by the oscillator in the time domain by using a dispersion element, then amplifies the widened pulse by using a laser gain medium, and finally compresses the amplified pulse by using an element with the opposite sign of the broadened dispersion, thereby effectively reducing the peak power density of the laser pulse in the amplification process.

At present, optical elements providing chromatic dispersion can be combined into a stretcher and a compressor matched with chromatic dispersion according to the requirements of different laser systems on chromatic dispersion, the stretcher and the compressor comprise high-chromatic dispersion glass stretching and prism pair compression, grating pair stretching and grating pair compression, chirped Bragg grating stretching and grating pair compression, high-chromatic dispersion glass stretching and prism pair compression and the like, wherein the chromatic dispersion provided by a combined structure based on grating pair stretching and compression is large, the design flexibility is strong, the stretcher and the compressor are widely applied to practice, and particularly the stretcher and the compressor based on single transmission grating can meet the requirements of the stretcher and the compressor at the same time only by one grating.

The traditional single transmission grating broadening compressor is applied to a chirp amplification system with a bandwidth of 1-2nm, and in order to ensure enough dispersion, the size of the whole device is very large, and the stability is reduced.

SUMMERY OF THE UTILITY MODEL

In view of the above, the present application provides an ultrafast laser broadening compressor based on a single transmission grating, wherein a hollow right-angle reflector is added in the broadening process, the symmetrical imaging of the sagittal plane of a lens is utilized, the optical path is translated and reflected again according to the original reflection path, and the broadening amount can be doubled while the volume of the device is controlled.

According to an aspect of the application, an ultrafast laser broadening compressor based on a single transmission grating is provided, which is used for broadening and compressing ultrafast laser and comprises a body;

the inner cavity of the body is provided with a supporting plate, and the upper end of the supporting plate is provided with a first climbing mirror, a grating, a plano-convex lens, a first reflector, a second reflector, a third reflector, a fourth reflector and a hollow right-angle reflector; the front end of the body is provided with a first penetration hole;

the first climbing mirror is arranged at a position close to the first incident hole, the grating is arranged at the rear end of the first climbing mirror, and a preset angle is formed between the grating and the first climbing mirror;

the laser is guided into the planoconvex lens through the grating, passes through the planoconvex lens, reaches the first reflector, is reflected to the second reflector by the first reflector, and is sequentially reflected back to the first reflector, the planoconvex lens, the grating and the first climbing mirror by the second reflector, after multiple reflections among the first climbing mirror, the grating, the first reflector and the second reflector, is guided into the third reflector through the grating, and after being guided into the fourth reflector through the third reflector, is guided into the hollow right-angle reflector, and after being translated by the hollow right-angle reflector for a preset length, is guided into the fourth reflector;

the upper end of the supporting plate is also provided with a fifth reflector, a sixth reflector and a second climbing mirror, the upper end and the lower end of the supporting plate are symmetrically provided with folding mirrors, and the lower end of the supporting plate is provided with a turning mirror; a second penetration hole is formed beside the body;

the amplified laser is guided into the fifth reflector through the second incident hole, enters the sixth reflector after being reflected by the fifth reflector, enters the folding mirror after being reflected to the grating by the sixth reflector, is reflected to the turn-back mirror through the folding mirror, generates a certain displacement in the horizontal direction through light paths in front of and behind the turn-back mirror, is then reflected back to the folding mirror and the grating in sequence, and climbs to a preset height through the second climbing mirror after passing through the grating;

the front end of the body is also provided with an exit hole, and the exit hole is opposite to the first incident hole.

In a possible implementation, the preset angle between the grating and the first climbing mirror is 60.9 °.

In one possible implementation, the perpendicular distance from the center of the plano-convex lens to the support plate is 36 mm.

In one possible implementation, the vertical distance from the uppermost end of the third mirror to the support plate is 35 mm.

In a possible implementation manner, the second incident hole is disposed at a position on one side of the body, close to the front end of the body, and is located on the oblique front side of the grating.

In a possible implementation manner, the preset included angle between the upper portion of the folding mirror and the supporting plate is 45 °, and the preset included angle between the lower portion of the folding mirror and the supporting plate is also 45 °.

In a possible implementation manner, the folding mirror is coaxially arranged with the lower part of the folding mirror, and the left and right side lenses of the folding mirror are 90 degrees in the horizontal direction.

In a possible implementation mode, the lower end of the supporting plate is further provided with a displacement table, and the displacement table is fixedly connected with the turning mirror in a threaded manner.

In one possible implementation, the fifth mirror has a mirror height lower than the sixth mirror.

In a possible implementation manner, the exit hole is arranged at the front end of the body close to the second entrance hole.

The ultrafast laser broadening compressor based on single transmission grating of the embodiment of the application has the following beneficial effects: after the laser passes through the grating arranged in the cavity for diffraction, the laser is reflected for multiple times between mirror parts such as the grating and the like in the device for broadening. A hollow right-angle reflecting mirror is additionally arranged in the widening process, so that the light beam after once widening can be horizontally translated by 5mm and reversely propagated, and the last light path widening is repeated again, namely, the widening amount is doubled while the volume of the device is controlled. And the output light rays enter the device again after being amplified outside the high-output device such as the expanded emergent laser and the incident laser, and are compressed by the optical path of the compressor to obtain the optimal dispersion compensation. The laser expands once, namely, four times of diffraction occurs on the same grating to form two grating pairs, namely, the two grating pairs carry the dispersion amount which is twice of that of the equivalent grating pair, and the hollow right-angle transmitting mirror translates the light path to enable the laser to expand twice, so that the laser can carry the dispersion amount which is four times of that of the equivalent grating pair, the volume is reduced while the expansion amount is doubled, and the cost is saved.

Other features and aspects of the present application will become apparent from the following detailed description of exemplary embodiments, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate exemplary embodiments, features, and aspects of the application and, together with the description, serve to explain the principles of the application.

FIG. 1 shows an optical schematic of a single transmission grating based ultrafast laser stretching compressor of an embodiment of the present application;

FIG. 2 is a top view of the internal structure of a single transmission grating based ultrafast laser stretching compressor according to an embodiment of the present application;

fig. 3 shows a bottom view of the internal structure of the ultrafast laser stretching compressor based on single transmission grating according to the embodiment of the present application.

Detailed Description

Various exemplary embodiments, features and aspects of the present application will be described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers can indicate functionally identical or similar elements. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

It will be understood, however, that the terms "central," "longitudinal," "lateral," "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in an orientation or positional relationship indicated in the drawings for convenience in describing the present application or for simplicity of description, and do not indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be considered limiting of the present application.

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 application, "a plurality" means two or more unless specifically limited otherwise.

The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

Furthermore, in the following detailed description, numerous specific details are set forth in order to provide a better understanding of the present application. It will be understood by those skilled in the art that the present application may be practiced without some of these specific details. In some instances, methods, means, elements and circuits that are well known to those skilled in the art have not been described in detail so as not to obscure the present application.

Fig. 1 shows an optical schematic diagram of a single-transmission-grating-based ultrafast laser stretching compressor according to an embodiment of the present application, and fig. 2 shows a top view of an internal structure of the single-transmission-grating-based ultrafast laser stretching compressor according to an embodiment of the present application; fig. 3 shows a bottom view of the internal structure of the ultrafast laser stretching compressor based on single transmission grating according to the embodiment of the present application.

As shown in fig. 1 and fig. 2, the ultrafast laser broadening compressor based on single transmission grating is used for broadening and compressing ultrafast laser, and is characterized by comprising a body 100; a supporting plate 200 is arranged in the inner cavity of the body 100, and a first climbing mirror 140, a grating 120, a plano-convex lens 150, a first reflector 111, a second reflector 112, a third reflector 113, a fourth reflector 114 and a hollow right-angle reflector 130 are arranged at the upper end of the supporting plate 200; the front end of the body 100 is provided with a first penetration hole 300; the first climbing mirror 140 is arranged at a position close to the first penetration hole 300, and the grating 120 is arranged at the rear end of the first climbing mirror 140 and has a preset angle with the first climbing mirror 140; the laser is guided into the planoconvex lens 150 through the grating 120, passes through the planoconvex lens 150, then reaches the first reflector 111, is reflected to the second reflector 112 by the first reflector 111, and is reflected back to the first reflector 111, the planoconvex lens 150, the grating 120 and the first climbing mirror 140 in sequence by the second reflector 112, after multiple reflections among the first climbing mirror 140, the grating 120, the first reflector 111 and the second reflector 112, is guided into the third reflector 113 through the grating 120, and is guided into the hollow right-angle reflector 130 after being guided into the fourth reflector 114 by the third reflector 113, and is guided into the fourth reflector 114 after being translated by the hollow right-angle reflector 130 for a preset length; the upper end of the support plate 200 is also provided with a fifth reflector 115, a sixth reflector 116 and a second climbing mirror 190, the upper end and the lower end of the support plate 200 are symmetrically provided with folding mirrors 170, and the lower end of the support plate 200 is provided with a turning mirror 180; a second penetration hole 310 is formed beside the body 100; the amplified laser is guided into the fifth reflector 115 through the second incident hole 310, enters the sixth reflector 116 after being reflected by the fifth reflector 115, enters the folding mirror 170 after being reflected to the grating 120 by the sixth reflector 116, is reflected to the turn-back mirror 180 through the folding mirror 170, generates a certain displacement in the horizontal direction through the light path in front of and behind the turn-back mirror 180, is then reflected back to the folding mirror 170 and the grating 120 in sequence, and is climbed to a preset height by the second climbing mirror 190 after passing through the grating 120; the front end of the body 100 is further provided with an exit hole 320, and the exit hole 320 is opposite to the first entry hole 300.

In this embodiment, the seed light enters the inside of the body 100 at a height of 39mm relative to the supporting plate 200 and passes through the first climbing mirror 140, and it should be noted that the first climbing mirror 140 is assembled by two 45 ° reflecting mirrors at a mirror surface included angle of 90 ° in the vertical direction, and the two mirrors are both 50 × 10mm and have a light passing slit in the middle. The seed light is incident on the surface of the grating 120 at 60.9 degrees through the slit, the first diffraction occurs on the surface of the grating 120, the originally circular light spot is dispersed into a line in the horizontal direction due to the introduction of a large amount of dispersion, and then passes through the plano-convex lens 150, wherein the distance between the plano-convex lens 150 and the diffraction point of the grating 120 is 50 mm. Specifically, after the laser with dispersion passes through the optical axis of the plano-convex lens 150, the originally dispersed light in the horizontal direction is affected by the plano-convex lens 150 to be spread by linear light spots close to parallel, and the linear light spots in the vertical direction intersect with the optical axis on the focal plane of the plano-convex lens 150. The light passing through the plano-convex lens 150 is reflected to the second reflecting mirror 112 by the first reflecting mirror 111, and then reflected back to the plano-convex lens 150 by the second reflecting mirror 112 through the first reflecting mirror 111 in sequence, wherein the first reflecting mirror 111 is a plane reflecting mirror with a size of 60 × 30 × 10mm and is assembled at 30 ° with respect to the front side of the body 100, and the second reflecting mirror 112 is also a plane reflecting mirror with a size of 40 × 10mm and is assembled at 0 ° with respect to the front side of the body 100. It should be noted here that the light returning to the plano-convex lens 150 is distributed symmetrically along the optical axis with the light passing through the plano-convex lens 150 for the first time, and then reaches the surface of the grating 120 again to perform the second diffraction during the broadening process, at this time, the laser has already passed through a martindz grating pair structure and still has a linear spot. The laser light passing through the grating 120 reaches the lower half of the first climbing mirror 140, and travels back to the grating 120 after being raised by 12mm inside the first climbing mirror 140, and the light height at this time is 45 mm. The third diffraction in the broadening process occurs when the light enters the grating 120 again, then passes through the upper part of the planoconvex lens 150 to the first reflecting mirror 111, is reflected to the second reflecting mirror 112 by the first reflecting mirror 111, is reflected back to the planoconvex lens 150 along the original path through the second reflecting mirror 112 again, the light height when passing through the planoconvex lens 150 is 27mm, then the fourth diffraction occurs when the light enters the grating 120 again, and the light spot becomes circular. The height of the light after the fourth diffraction is less than the upper edge of the third reflector 113, so the light is reflected to the fourth reflector 114 by the third reflector 113, and is reflected to the hollow cube corner reflector 130 by the fourth reflector 114. Specifically, the third mirror 113 and the fourth mirror 114 are plane mirrors, each having a size of 15 × 6, and both of them are 45 ° with respect to the front side of the body 100.

It should be noted that, two 45 ° reflectors are assembled inside the hollow corner reflector 130 at a mirror surface included angle of 90 ° in the horizontal direction, so that the light beam is incident on the mirror far away from the first climbing mirror 140, and is reflected by the mirror to the other mirror, thereby achieving the purpose of translating the light path by 5 mm. The translated light is reflected to the third reflector 113 through the fourth reflector 114, reflected to the grating 120 through the third reflector 113, diffracted for four times again on the same grating according to the optical path before translation, and finally emitted from the first incident hole 300, and the emitted laser and the incident laser have the same height, so that the whole widening process is completed. In the broadening process, eight times of diffraction occur on the same grating, and the broadening amount of laser pulses is increased.

It should be further noted that the broadened laser light is amplified outside the device, enters the interior via the second entrance hole 310 to be broadened, enters the fifth reflector 115 with a light height of 30mm, and is reflected to the sixth reflector 116 via the fifth reflector 115, and is reflected to one end of the grating 120 by the sixth reflector 116, and is reflected to the lower end of the supporting plate 200 by the folding mirror 170 after undergoing the first diffraction in the compression process. It should be noted here that the folding mirror 170 is assembled by two 45 ° mirrors with a mirror surface included angle of 90 ° in the vertical direction, specifically, the two mirrors are 60 × 40 × 10mm in size, symmetrically disposed at the upper end and the lower end of the support plate 200, and reflected by the upper mirror to the lower mirror, so as to achieve the purpose of guiding the laser to the lower end of the support plate 200, the laser is reflected to the folding mirror 180 through the folding mirror 170, the folding mirror 180 is disposed at the lower end of the support plate 200, specifically, two 45 ° mirrors are assembled with a mirror surface included angle of 90 ° in the horizontal direction, the laser is reflected back to the folding mirror 170 through the folding mirror 180, and is reflected to the other end of the grating 120 by the folding mirror 170, and then enters the second climbing mirror 190, and then the second climbing mirror 190 climbs up to 42mm, and then enters the grating again, and then the third diffraction occurs in the compression process, and returns to the same grating 120 after being reflected according to the aforementioned compression route, the fourth diffraction in the compression process occurs, and finally the fourth diffraction is reflected to the outside of the device by the sixth reflector 116, and the twelve diffractions are generated on the same grating 120 with the broadening process at the end of the compression process, so that the broadening amount is increased, the volume of the device is reduced, and the manufacturing cost is saved.

In one embodiment, the predetermined angle between the grating 120 and the first climbing mirror 140 is 60.9 °.

In this embodiment, the angle between the grating 120 and the first climbing mirror 140 is 60.9 °, that is, the laser is incident on the surface of the grating 120 at 60.9 °, it should be noted that the grating coefficient of the grating 120 used in the present apparatus is 1700gr/nm, the size is 102 × 28 × 6mm, and the single diffraction efficiency is 97%. The dispersion amount of laser broadening depends on the distance between grating pairs, in the device, the oblique distance between the grating pairs is 2(F-L), wherein F is the focal length of the plano-convex lens, namely 400mm, and L is the vertical distance from the plano-convex lens to the center of a grating diffraction point, namely 50 mm. The grating with the grating parameter of 1700gr/nm is used at the wavelength of 1030nm, the grating is incident at 60.9 degrees, and under the condition, the second-order dispersion quantity provided by the broadened laser is 6.59-10 ⁷ fs ² 。

In one embodiment, the perpendicular distance from the center of the plano-convex lens 150 to the support plate 200 is 36 mm.

In this embodiment, the laser beam enters the device with a height of 39mm, and is located 3mm above the optical axis when passing through the plano-convex lens 150, so that the laser beam is incident on the first reflector 111 at a certain angle, and is reflected back to the first reflector 111 by the second reflector 112, and then is guided into the plano-convex lens 150 by the first reflector 111, and the light beam is located 3mm below the optical axis, i.e. the distance from the support plate 200 is 36mm, which is symmetrical to the light beam passing through the plano-convex lens 150 for the first time along the optical axis.

In one embodiment, the vertical distance from the uppermost end of the third reflecting mirror 113 to the support plate 200 is 35 mm.

In this embodiment, the vertical distance from the uppermost end of the third reflector 113 to the supporting plate 200 is less than the light height after the second diffraction, so that the laser in the broadening process can penetrate the grating 120 to be diffracted for the second time and then enter the first climbing mirror 140 from above the third reflector 113, thereby achieving the purpose of climbing.

In one embodiment, the second penetration hole 310 is disposed on one side of the body 100 near the front position of the body 100 and on the oblique front side of the grating 120.

In this embodiment, the expanded laser beam exits the device along the first entry hole 300, is amplified outside the device, and then exits the device again through the second entry hole 310 to be compressed. Specifically, after the laser light enters the fifth mirror 115, the laser light is reflected by the fifth mirror 115 to the sixth mirror 116, and then reflected by the sixth mirror 116 to the grating 120. The angle of the incident grating 120 needs to be finely adjusted according to the compression result, and the compression after laser is widened and then enlarged needs to compensate not only the amount of chromatic dispersion introduced during widening but also the material dispersion introduced during enlargement, wherein the incident angle of the incident grating during compression determines whether the second-order dispersion and the third-order dispersion can be simultaneously compensated to be optimal at the same grating pair pitch, so that a grating with a grating parameter of 1700gr/nm is used at a wavelength of 1030nm, the angle of the incident grating during laser widening is 60.9 °, when the focal length of the plano-convex lens is F ═ 400mm, the angle of the laser incident grating during compression needs to be 61 °, that is, the included angle between the laser incident from the second incident hole 310 and the fifth reflector 115 is 61 °.

It should be noted that the fifth mirror 115 has two dimensions that can be adjusted, and the angle at which the laser enters the grating 120 can be adjusted according to the required compression result, so as to meet the use requirement.

In one embodiment, the predetermined angle between the upper portion of the folding mirror 170 and the supporting plate 200 is 45 °, and the predetermined angle between the lower portion of the folding mirror 170 and the supporting plate 200 is 45 °.

In this embodiment, the laser beam is guided by the sixth mirror 116 to one end of the grating 120, is diffracted for the first time during compression, enters the upper portion of the folding mirror 170 from the grating 120, is reflected from the upper portion of the folding mirror 170 to the lower portion thereof, and is reflected from the lower portion to the turning mirror 180. The laser light is guided into the lower part of the support plate by the folding mirror 170, which effectively reduces the size of the device.

In one embodiment, the folding mirror 180 is coaxially disposed with the lower portion of the folding mirror 170, and the left and right lenses of the folding mirror 180 are 90 ° in the horizontal direction.

In this embodiment, the laser beam is reflected from the lower portion of the folding mirror 170 to one side mirror of the folding mirror 180, then reflected from one side mirror of the folding mirror 180 to the other side mirror, reflected back to the folding mirror 170 through the other side mirror, and then reflected from the folding mirror 170 to the other end of the grating 120, and undergoes the second diffraction in the compression process, and the specific folding mirror 180 is assembled by two 45 ° mirrors at a mirror surface included angle of 90 ° in the horizontal direction, and the mirror sizes are all 60 × 40 × 10 mm.

It should be noted that, after the laser is diffracted for the second time, the laser is guided into the second climbing mirror 190, the second climbing mirror 190 is assembled by two mirrors with 45 degrees and a mirror surface included angle of 90 degrees in the vertical direction, the laser is emitted into one end of the grating 120 after the second climbing mirror climbs to 42mm, the third diffraction occurs in the compression process, and then the laser is reflected according to the compression light path and finally reflected to the other end of the grating 120, that is, the fourth diffraction occurs in the compression process. Because the laser passes through the widening optical path twice in the device, in order to compensate the dispersion amount introduced in the widening process, the turn-back mirror 180 is arranged at the position which is about 1.3m away from the grating, so that the dispersion amount introduced in the widening process is compensated, and meanwhile, the turn-back mirror 180 receives the laser reflected from the lower part of the folding mirror 170, so that the transmission of the optical path at the lower part of the supporting plate is facilitated, and the whole volume of the device is reduced.

In one embodiment, as shown in fig. 3, a displacement table 160 is further disposed at the lower end of the support plate 200, and the displacement table 160 is screwed with the folding mirror 180.

In this embodiment, the mounting frame of the folding mirror 180 is fixed on the displacement table 160 by screwing screws, specifically, the displacement table 160 is an electric displacement table, the driver 161 of the electric displacement table is arranged at the rear end of the body, and the position of the folding mirror 180 is adjusted by controlling the electric displacement table 160 through the driver 161, so that the grating pair interval is changed, the compression effect is optimized, the adjustment in the compression process is facilitated to a greater extent, the adjustment efficiency is improved, and the future maintenance is facilitated.

In one embodiment, fifth mirror 115 is at a lower mirror height than sixth mirror 116.

In this embodiment, the distance from the upper edge of the fifth mirror 115 to the support plate 200 is 35mm, the height of the laser beam after the fourth diffraction is 42mm, and the laser beam is guided into the sixth mirror 116 by the grating 120, and since the height of the center of the sixth mirror 116 is greater than that of the fifth mirror 115, the laser beam with the height of 42mm can pass through the fifth mirror 115, which helps to guide the laser beam out of the device.

In one embodiment, the exit hole 320 is disposed at the front end of the body 100 near the second entrance hole 310.

In this embodiment, the laser light for compression is emitted from the exit hole 320 to the outside of the device.

In summary, the laser is firstly broadened by the device, the broadened laser is amplified outside the device, and then is introduced into the device again for compression, and the dispersion carried by the compressed laser pulse can be well compensated. Specifically, in the widening process, the hollow right-angle reflecting mirror 130 is additionally arranged, so that the optical path widened once can be horizontally moved by 5mm, and the purpose of widening the optical path again according to the widening performed for the first time is achieved. The whole broadening process generates eight diffraction times on the same grating 120, which is equivalent to carrying four times of the dispersion of the equivalent grating. And then amplifying the broadened laser outside the device, and enabling the amplified laser to enter the device again for compression. Because the second-order dispersion and the third-order dispersion are introduced in the broadening process and the amplifying process, the angle of the laser incident grating in the compressing process can be adjusted according to the required compressing result, so that the laser can simultaneously compensate the second-order dispersion and the third-order dispersion introduced in the broadening and amplifying processes under the same grating. Meanwhile, the folding mirror 170 and the folding mirror 180 are additionally arranged in the compression process and can guide the light path into the lower part of the inner support plate 200 of the device, so that the utilization frequency of the same grating 120 in the compression process reaches four times, namely the utilization frequency of the same grating in the whole widening compression process is twelve times, the overall compression efficiency reaches 85 percent, and the manufacturing cost is saved while the volume of the device is effectively reduced.

Having described embodiments of the present application, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen in order to best explain the principles of the embodiments, the practical application, or improvements made to the technology in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. An ultrafast laser widening compressor based on a single transmission grating is used for widening and compressing ultrafast laser and is characterized by comprising a body;

2. The single transmission grating-based ultrafast laser stretching compressor of claim 1, wherein the preset angle between said grating and said first climbing mirror is 60.9 °.

3. The single transmission grating-based ultrafast laser stretching compressor of claim 1, wherein a vertical distance from a center of said plano-convex lens to said supporting plate is 36 mm.

4. The single transmission grating-based ultrafast laser stretching compressor of claim 1, wherein a vertical distance from an uppermost end of said third reflecting mirror to said supporting plate is 35 mm.

5. The single transmission grating ultrafast laser stretching compressor of claim 1, wherein said second incident hole is disposed at a position of said body side near said body front position and at a position of said grating slant front side.

6. The single transmission grating ultrafast laser stretching compressor of claim 1, wherein the predetermined angle between the upper portion of the folding mirror and the supporting plate is 45 °, and the predetermined angle between the lower portion of the folding mirror and the supporting plate is 45 °.

7. The single-transmission-grating ultrafast laser stretching compressor of claim 6, wherein the folding mirror is coaxially disposed with the lower portion of the folding mirror, and left and right side lenses of the folding mirror are 90 ° in a horizontal direction.

8. The ultrafast laser stretching compressor of single transmission grating of claim 7, wherein the lower end of the supporting plate is further provided with a displacement table, and the displacement table is screwed and fixed with the folding mirror.

9. The single transmission grating ultrafast laser stretching compressor of claim 1, wherein a mirror height of said fifth mirror is lower than said sixth mirror.

10. The single transmission grating ultrafast laser stretch compressor of claim 1, wherein said exit aperture is disposed at said body front end proximate to said second entrance aperture.