A calibration device and a calibration method for an optical path transmission module

Abstract

The present invention discloses a calibration device and a calibration method for an optical path transmission module, which relates to the technical field of excimer lasers and is used for calibrating an optical path transmission module. The calibration device includes two first optical slits, two second optical slits and a line light source. In a first calibration state, the surface of the first electrode facing the second electrode is coplanar with the center line of the first line slit, and the surface of the first electrode facing the second electrode is perpendicular to the height direction of the amplifying cavity; in a second calibration state, the center line of the second line slit is coplanar with the center line of the first electrode and the second electrode in the height direction of the amplifying cavity, and the coplanarity is perpendicular to the height direction of the amplifying cavity; the line light source emits a line light beam passing through the two first line slits and the amplifying cavity in the first calibration state, and emits a line light beam passing through the two second line slits and the amplifying cavity in the second calibration state.

Description

Technical Field

[0001] The present invention relates to the technical field of excimer lasers, and in particular to a calibration device and a calibration method for an optical path transmission module. Background Art

[0002] Lithography is the largest industrial application field of excimer lasers. As the lithography node is about to enter the 32nm node, ArF excimer lithography has become the mainstream and is expected to be applied to the lower 22nm node and 16nm node. In this regard, the current research hotspots of excimer laser technology are mainly focused on excimer laser technology for lithography. As the lithography node decreases, ArF excimer lasers are required to have more stable narrow spectral line width, greater output power, higher dose stability and longer gas life. At present, ArF excimer lasers have two discharge cavities, one is the seed cavity (MO cavity) and the other is the gain amplifier cavity (PA cavity). By using the ring cavity technology, the seed light in the seed cavity is input into the gain amplifier cavity multiple times, and the residence time in the amplifier cavity is long, and the amplifier cavity works in a deep saturation state.

[0003] Accurately controlling the optical path through the gain zone of the gain amplifier cavity determines the success or failure of the ring cavity technology. The current design of the gain amplifier cavity can be adjusted in the horizontal direction, and the vertical direction is determined by the installation reference. The beam transmission can be followed by the two-dimensional angle adjustment of the reflector. The optical axis of the beam and the center line of the discharge cavity should be consistent. If they are not consistent, part of the light will be blocked and cannot enter the gain zone. The direct impact is that the laser energy of a single pulse is reduced and the vertical size of the spot is reduced. Summary of the invention

[0004] The object of the present invention is to provide a light path transmission module calibration device and calibration method, which are used to calibrate the light path transmission module to prevent the light beam from being blocked and unable to completely pass through the gain region.

[0005] In a first aspect, the present invention provides a calibration device for an optical transmission module. The calibration device includes two first optical slits, two second optical slits and a line light source. Each first optical element has a first line slit, and each second optical element has a second line slit.

[0006] In the first adjustment state, each first optical element is disposed on a corresponding light-transmitting window, that is, one first optical element can be disposed on one light-transmitting window. The surface of the first electrode facing the second electrode is coplanar with the center line of the first line slit, and the surface of the first electrode facing the second electrode is perpendicular to the height direction of the amplifying cavity. For the convenience of description, Figure 1The height direction of the amplifying cavity 1 is defined as being consistent with the up-down direction of the drawing, and the first electrode is located at the bottom. The surface of the first electrode facing the second electrode is referred to as the top of the first electrode. In this way, in the height direction of the amplifying cavity, the top of the first electrode is at the same height as the center line of the first word line slit.

[0007] In the second adjustment state, each second optical element is arranged on the corresponding light-transmitting window, that is, one second optical element can be arranged on one light-transmitting window. The center line of the second straight line slit is coplanar with the center line of the first electrode and the second electrode in the height direction of the amplifying cavity, and the coplanarity is perpendicular to the height direction of the amplifying cavity. In other words, in the height direction of the amplifying cavity, the distance between the center line of the second straight line slit and the first electrode is equal to the distance between the center line of the second straight line slit and the second electrode. The center line of the first electrode and the second electrode in the height direction of the amplifying cavity can be called the amplifying cavity center line, and the center line of the second straight line slit can coincide with the center line of the amplifying cavity.

[0008] The adjustment device has a first adjustment state and a second adjustment state. The straight-line light source is located on a side of the amplifying cavity close to the first reflecting element in both the first adjustment state and the second adjustment state, and is used to emit a straight-line light beam passing through two first straight-line slits and the amplifying cavity in the first adjustment state, and to emit a straight-line light beam passing through two second straight-line slits and the amplifying cavity in the second adjustment state.

[0009] Through the above technical solution, in the first adjustment state, since the two first optical elements are located on both sides of the amplifying cavity, and the center line of the first straight-line slit and the top of the first electrode are located on the same plane, therefore, when the straight-line light source emits a straight-line light beam passing through the two first straight-line slits and the amplifying cavity in the first adjustment state, it means that the light outlet of the straight-line light source can emit a straight-line light beam that locks the top position of the first electrode in the current posture. At the same time, in the second adjustment state, the center line of the second straight-line slit can coincide with the center line of the amplifying cavity. Based on this, when the light outlet posture of the straight-line light source remains constant, when the straight-line light source emits a straight-line light beam passing through the two second straight-line slits and the amplifying cavity in the second adjustment state, it can be determined that: the light beam that can pass through the two second straight-line slits and the amplifying cavity is, in theory, not only parallel to the straight-line light beam passing through the top of the first electrode, but also passes through the center of the amplifying cavity. On this basis, the first reflecting element and / or the second reflecting element can be used to adjust the incident angle of the seed light entering the amplifying cavity, so that the seed light reflected by the second reflecting element passes through the amplifying cavity and the two second straight-line slits, which can indicate that the optical axis of the seed light passes through the center of the amplifying cavity, thereby ensuring that the size of the laser spot after amplification by the optical path transmission module in the height direction of the amplifying cavity meets the requirements and avoids a large loss of laser energy. Therefore, the adjustment device provided in the present application can adjust the optical path transmission module, which can prevent the light beam from being blocked and unable to completely pass through the gain region. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0011] Figure 1 A schematic diagram of the calibration device provided by an embodiment of the present invention when calibrating the amplifying cavity in the first calibration state;

[0012] Figure 2 A schematic diagram of the calibration device provided by an embodiment of the present invention when calibrating the amplifying cavity in the first calibration state;

[0013] Figure 3 A schematic diagram of the calibration device provided by an embodiment of the present invention calibrating the amplifying cavity in the second calibration state;

[0014] Figure 4 A schematic diagram of the calibration device provided by an embodiment of the present invention calibrating the amplifying cavity in the second calibration state;

[0015] Figure 5 A schematic diagram of the adjustment device provided in an embodiment of the present invention when adjusting the seed light;

[0016] Figure 6A schematic diagram of a first optical slit provided in an embodiment of the present invention;

[0017] Figure 7 A schematic diagram of a second optical slit provided in an embodiment of the present invention.

[0018] Reference numerals:

[0019] 1- amplification cavity, 11- first electrode, 12- second electrode, 13- light-transmitting window, 2- linear light source,

[0020] 3-first optical element, 4-second optical element, 5-third optical element,

[0021] 6-first reflecting element, 7-second reflecting element. DETAILED DESCRIPTION

[0022] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0023] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0024] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. The meaning of "several" is one or more, unless otherwise clearly and specifically defined.

[0025] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by the terms "up", "down", "front", "back", "left", "right", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0026] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] See also Figure 1 As shown, the excimer laser has an optical path transmission module, which includes a first reflecting element 6, a second reflecting element 7, and an amplifying cavity 1 of the laser located between the first reflecting element 6 and the second reflecting element 7, wherein the amplifying cavity 1 has a first electrode 11 and a second electrode 12 arranged opposite to each other, and the first electrode 11 and the second electrode 12 are distributed in the height direction of the amplifying cavity 1; the amplifying cavity 1 has two light-transmitting windows 13 arranged opposite to each other. The present invention provides a calibration device for an optical path transmission module, which is used for calibrating the optical path transmission module.

[0028] See also Figures 1 to 7 As shown, the calibration device provided by the embodiment of the present invention comprises two first optical elements 3, two second optical elements 4 and a line light source 2. Each first optical element 3 has a first line slit, and each second optical element 4 has a second line slit.

[0029] In the first adjustment state, each first optical element 3 is disposed on a corresponding light-transmitting window 13, that is, one first optical element 3 can be disposed on one light-transmitting window 13. The surface of the first electrode 11 facing the second electrode 12 is coplanar with the center line of the first line slit, and the surface of the first electrode facing the second electrode is perpendicular to the height direction of the amplifying cavity. Figure 1 The height direction of the amplifying cavity 1 is defined as being consistent with the up-down direction of the drawing, and the first electrode 11 is located at the bottom. Hereinafter, the surface of the first electrode 11 facing the second electrode 12 is referred to as the top of the first electrode 11. In this way, in the height direction of the amplifying cavity 1, the top of the first electrode 11 and the center line of the first word line slit are located at the same height.

[0030] In the second adjustment state, each second optical element 4 is disposed on a corresponding light-transmitting window 13, that is, one second optical element 4 can be disposed on one light-transmitting window 13. The center line of the second straight line slit is coplanar with the center line of the first electrode 11 and the second electrode 12 in the height direction of the amplifying cavity, and the coplanarity is perpendicular to the height direction of the amplifying cavity. In other words, in the height direction of the amplifying cavity 1, the distance between the center line of the second straight line slit and the first electrode 11 is equal to the distance between the center line of the second straight line slit and the second electrode 13. The center line of the first electrode 11 and the second electrode 12 in the height direction of the amplifying cavity can be called the center line of the amplifying cavity 1, so that the center line of the second straight line slit can coincide with the center line of the amplifying cavity 1.

[0031] The adjustment device has a first adjustment state and a second adjustment state. The straight-line light source 2 is located on a side of the amplifying cavity 1 close to the first reflecting element 6 in both the first adjustment state and the second adjustment state, and is used to emit a straight-line light beam passing through two first straight-line slits and the amplifying cavity 1 in the first adjustment state, and to emit a straight-line light beam passing through two second straight-line slits and the amplifying cavity 1 in the second adjustment state.

[0032] Through the above technical solution, in the first adjustment state, since the two first optical elements 3 are located on both sides of the amplifying cavity 1, and the center line of the first straight-line slit and the top of the first electrode 11 are both located on the first plane, therefore, when the straight-line light source 2 emits a straight-line light beam passing through the two first straight-line slits and the amplifying cavity 1 in the first adjustment state, it means that the light outlet of the straight-line light source 2 is in the current posture, and the emitted straight-line light beam locks the top position of the first electrode 11, that is, the height of the straight-line light beam is the top position of the first electrode 11. At the same time, in the second adjustment state, the center line of the second straight-line slit can coincide with the center line of the amplifying cavity 1. Based on this, when the light outlet posture of the straight-line light source 2 remains constant, when the straight-line light source 2 emits a straight-line light beam passing through the two second straight-line slits and the amplifying cavity 1 in the second adjustment state, it can be determined that: the light beam that can pass through the two second straight-line slits and the amplifying cavity 1 is, in theory, not only parallel to the straight-line light beam passing through the top of the first electrode 11, but also passes through the center of the amplifying cavity 1. On this basis, the first reflecting element 6 and / or the second reflecting element 7 can be used to adjust the incident angle of the seed light entering the amplifying cavity 1, so that the seed light reflected by the second reflecting element 7 passes through the amplifying cavity 1 and the two second one-line slits, which can indicate that the optical axis of the seed light passes through the center of the amplifying cavity 1, thereby ensuring that the size of the laser spot after amplification by the optical path transmission module in the height direction of the amplifying cavity 1 meets the requirements and avoids a large loss of laser energy. Therefore, the adjustment device provided in the present application can adjust the optical path transmission module, which can prevent the light beam from being blocked and unable to pass through the gain region completely.

[0033] In a possible implementation, in the first adjustment state, each first optical element 3 is detachably mounted on the corresponding light-transmitting window 13; in the second adjustment state, each second optical element 4 is detachably mounted on the corresponding light-transmitting window 13. In this way, it is convenient to disassemble and install the first optical element 3 and install the second optical element 4.

[0034] In one example, if Figure 6 and Figure 7 As shown, the first optical element 3 and the second optical element 4 can be constructed as circular plates, and the circular plates are provided with slits. The circular plates can be provided with mounting holes at positions corresponding to the light-transmitting windows 13 so as to detachably mount the circular plates on the light-transmitting windows 13.

[0035] In a possible implementation, when the first optical element 3 is disposed on the corresponding light-transmitting window 13, the geometric center of the first optical element 3 can be made coaxial with the geometric center of the corresponding light-transmitting window 13. Since the distance a between the top of the first electrode 11 and the geometric center of the light-transmitting window 13 in the height direction of the amplifying cavity 1 is a constant, the distance between the geometric center of the first optical element 3 and the center line of the first straight-line slit can also be set to a; in this way, in the height direction of the amplifying cavity 1, the center line of the first straight-line slit can be located at the same height as the top of the first electrode 11.

[0036] When the second straight-line slit is arranged on the corresponding light-transmitting window 13, the geometric center of the second optical element 4 can be made coaxial with the geometric center of the corresponding light-transmitting window 13. Since the distance b between the geometric center of the light-transmitting window 13 and the center line of the amplifying chamber 1 in the height direction of the amplifying chamber 1 is a constant, the distance between the geometric center of the second optical element 4 and the center line of the second straight-line slit can be set to b; in this way, the center line of the second straight-line slit can be located at the same height as the center line of the amplifying chamber 1. In other words, the center line of the second straight-line slit can coincide with the center line of the amplifying chamber 1.

[0037] The height difference between the first adjustment state and the second adjustment state of the above-mentioned straight-line light source 2 is D, D=ab. Thus, in the first adjustment state, the light-emitting posture of the straight-line light source 2 is adjusted so that the straight-line light beam emitted by it can pass through the amplifying cavity 1 and the two first straight-line slits, and under the premise of keeping the light-emitting posture of the straight-line light source 2 unchanged, according to the positional relationship between the first straight-line slit and the second straight-line slit, the straight-line light source 2 is raised only in the height direction of the amplifying cavity 1 by the height difference D. As long as the position of the second straight-line slit is correct, the straight-line light beam emitted by the straight-line light source 2 can pass through the amplifying cavity 1 and the two second straight-line slits, and at this time, the position of the second straight-line slit is verified to be correct, and thus, the center line position of the first electrode 11 and the second electrode 12 in the height direction of the amplifying cavity is marked by the second straight-line slit.

[0038] In the height direction of the amplifying cavity 1, the center line of the amplifying cavity 1 and the geometric center of the light-transmitting window 13 may be located at different heights or at the same height, for example Figure 2 As shown, in one example, the center line of the amplifying cavity 1 and the geometric center of the light-transmitting window 13 are located at different heights, b=1.1 mm, a=6.9 mm.

[0039] In a possible implementation, the calibration device may further include fluorescent paper. In the first calibration state, the fluorescent paper is located between the second reflective element 7 and one of the first optical elements 3 close to the second reflective element 7. By utilizing the principle of generating a light spot when light is irradiated on the fluorescent paper, it is possible to verify whether the line light beam passes through the amplifying cavity 1 and the two first line light slits. It is also possible to further verify by the shape of the light spot whether the line light beam is blocked during the propagation process. Thus, the complete propagation of the line light beam can be achieved by fine-tuning the light emission posture of the line light source 2, thereby improving the accuracy of the light emission posture of the line light source 2. In the second calibration state, It provides a good reference benchmark for verifying the position accuracy of the second straight-line slit; similarly, in the second adjustment state, the fluorescent paper is located between the second reflective element 7 and one of the second optical elements 4 close to the second reflective element 7, so it can be verified whether the straight-line light beam passes through the amplifying cavity 1 and the two first straight-line slits, and it can also be further verified by the shape of the light spot whether the straight-line light beam is blocked during the propagation process, so that the complete propagation of the straight-line light beam can be achieved by fine-tuning the position of the second optical element 4 (that is, the straight-line light beam is not blocked during the propagation process), thereby improving the position accuracy of the second straight-line slit and improving the adjustment accuracy of the optical path transmission module.

[0040] After the second optical element 4 is installed on the light-transmitting window 13, due to the existence of mechanical errors, there may be a small gap between the center line of the second straight-line slit and the center line of the amplifying cavity 1; and, since the positions of the straight-line light source 2 in the first adjustment state and the second adjustment state are different, after the straight-line light source 2 is moved, the light-emitting posture of the straight-line light source 2 may have a small deviation; all of these will reduce the adjustment accuracy of the optical path transmission module. In order to reduce or avoid the adverse effects caused by these errors, in a possible implementation, the adjustment device may also include a third optical element 5 (such as Figure 5As shown), the third optical element 5 has a third straight-line slit; in the second adjustment state, the third optical element 5 can be located between the second straight-line slit and the straight-line light source 2, and the center of the light outlet of the straight-line light source 2 is at the same height as the center line of the third straight-line slit; then only when the light emission posture of the straight-line light source 2 is basically the same as that in the first adjustment state, the straight-line light beam emitted by the straight-line light source 2 in the second adjustment state can pass through the third straight-line slit, and then pass through the second straight-line slit and the amplifying cavity 1. In this way, the third straight-line slit can play a role in verifying the light emission posture of the straight-line light source 2. Since there may be installation errors in the second optical element 4, the position of the second optical element 4 can be fine-tuned in the entire second adjustment state so that the straight-line light beam passes through the second straight-line slit and the amplifying cavity 1.

[0041] In a possible embodiment, the third optical element 5 may be an adjustable mechanical slit, which facilitates adjustment of the size of the third straight-line slit so that the straight-line light beam can completely pass through the third straight-line slit, thereby improving adjustment accuracy.

[0042] In a possible implementation, the line light source 2 may be a line light source 2 with adjustable beam size, so that the size of the line light beam can be adjusted so that it can completely pass through the first line slit and the second line slit, thereby improving the calibration accuracy. The line light source 2 may be a line laser, and the calibration accuracy may be improved by utilizing the collimation characteristics of the laser. The line laser may be collimated by a Powell prism, and the light source has good consistency. In addition, the line laser may offset the horizontal displacement error caused by the gain amplifier cavity window, thereby improving the calibration accuracy.

[0043] In a possible embodiment, the width of the cross section of the line light beam provided by the line light source 2 is less than or equal to the width of the first line slit. In this way, the line light beam can completely pass through the first line slit and the second line slit, which is conducive to improving the adjustment accuracy.

[0044] In a possible embodiment, the width of the cross section of the line light beam provided by the line light source 2 is less than or equal to the width of the second line slit, and the width of the cross section of the line light beam provided by the line light source 2 is less than or equal to the width of the third line slit. It should be noted that the width of the second line slit refers to: the size of the second line slit in the height direction of the amplifying cavity 1; the width of the third line slit refers to: the size of the third line slit in the height direction of the amplifying cavity 1. In this way, in the height direction of the amplifying cavity 1, when the light emission posture of the line light source 2 is accurate and the position of the second line slit is accurate, the line light beam can pass through the second line slit and the third line slit completely without being blocked and enter the amplifying cavity 1. Therefore, this is conducive to improving the accuracy of the light emission posture of the line light source 2 and the accuracy of the position of the second line slit, and then it is conducive to improving the adjustment accuracy of the optical path transmission module.

[0045] It should be noted that, in this article, the width of the cross section of the line beam, the width of the first line slit, the width of the second line slit and the width of the third line slit all refer to their respective dimensions in the height direction of the amplifying cavity.

[0046] The embodiment of the present invention further provides a calibration method for an optical path transmission module, and the calibration method can apply the above-mentioned calibration device. The method provided by the embodiment of the present invention includes:

[0047] like Figure 1 As shown, each first optical element 3 is firstly arranged on a corresponding light transmission window 13 .

[0048] like Figure 2 As shown, then, the line light source 2 is arranged on the side of the first optical element 3 close to the first reflecting element 6, and the position and light emission posture of the line light source 2 are adjusted so that the line light beam emitted by the line light source 2 passes through the amplifying cavity 1 and the two first line slits. At this time, the light emission posture of the line light source 2 is determined.

[0049] like Figure 3As shown, then, under the premise of keeping the light-emitting posture of the straight-line light source 2 constant, the straight-line light source 2 is moved a distance D along the height increase direction of the amplifying cavity 1; wherein, D=ab, a is the distance between the geometric center of the first optical element 3 and the center line of the first straight-line slit; b is the distance between the geometric center of the second optical element 4 and the center line of the second straight-line slit. According to the above description of the distance b, after the movement is completed, the straight-line light beam emitted by the straight-line light source 2 can pass through the center line of the second straight-line slit, and also pass through the center line of the amplifying cavity 1, so that the seed light can pass through the center of the amplifying cavity 1. Then, after removing the first optical element 3, each second optical element 4 is disposed on the corresponding light-transmitting window 13, so that the second straight-line slit and the center of the light outlet of the straight-line light source 2 are at the same height.

[0050] like Figure 4 As shown, a straight-line light source 2 is used to emit a straight-line light beam passing through two second straight-line slits and the amplifying cavity 1. At this time, the position of the second optical element 4 is determined, and the second optical element 4 can be used to adjust the optical path transmission module.

[0051] Finally, if Figure 5 As shown, the posture of the first reflecting element 6 and / or the posture of the second reflecting element 7 are adjusted to utilize the first reflecting element 6 and / or the second reflecting element 7 to adjust the incident angle of the seed light entering the amplifying cavity 1, so that the seed light reflected by the second reflecting element 7 passes through the amplifying cavity 1 and the two second one-line slits, thereby completing the adjustment of the optical path transmission module.

[0052] Among them, firstly, the seed light is irradiated on the first reflecting element 6, and then the posture of the first reflecting element 6 is adjusted so that the seed light reflected by the first reflecting element 6 can pass through the third one-line slit, the second one-line slit and the amplifying cavity 1, and irradiate on the second reflecting element 7; then, the posture of the first reflecting element 6 and / or the second reflecting element 7 is adjusted so that the seed light reflected by the second reflecting element 7 can pass through the second one-line slit, the amplifying cavity and the third one-line slit. At this time, the adjustment of the optical path transmission module is completed. The seed light reflected by the first reflecting element 6 and passing through the amplifying cavity 1, and the seed light reflected by the second reflecting element 7 and passing through the amplifying cavity 1 can both pass through the central area of ​​the amplifying cavity 1. Among them, the posture of the first reflecting element 6 and the posture of the second reflecting element 7 both refer to the inclination angle of the reflecting element relative to the center line of the amplifying cavity 1.

[0053] It should be noted that: the seed light reflected by the first reflective element 6 and passing through the amplifying cavity 1 has an angle A with the seed light reflected by the second reflective element 7 and passing through the amplifying cavity 1, and A≤8mrad. Since the angle A is small, both seed lights can pass through the third line slit and the second line slit. Figure 5As shown, the seed light reflected by the second reflecting element 7 and passing through the amplifying cavity 1 may coincide with the center line of the amplifying cavity 1 , and an angle a is formed between the seed light reflected by the first reflecting element 6 and passing through the amplifying cavity 1 and the center line of the amplifying cavity 1 .

[0054] In a possible implementation, the first reflective element 6 may be a tunable reflector, and the second reflective element 7 may include two tunable reflectors, namely a first reflector 71 and a second reflector 72, so as to reflect the received seed light again and make it pass through the amplifying cavity 1 again.

[0055] Before using the line light source 2 to emit a line light beam through the amplifying cavity 1 and the two first line slits, it is necessary to adjust the light emission posture of the line light source 2. The light emission posture of the line light source 2 can be understood as: the emission direction of the light relative to the amplifying cavity 1.

[0056] In a possible implementation, when the calibration device includes a third optical element 5, the calibration method further includes: after using the line light source 2 to emit a line light beam passing through two first line slits and the amplifying cavity 1, before using the line light source 2 to emit a line light beam passing through the amplifying cavity 1 and two second line slits; placing a third optical element 5 having a third line slit between the amplifying cavity 1 and the first reflecting element 6; then, when the light emission posture of the line light source 2 is constant, adjusting the size of the third line slit so that the line light beam completely passes through the third line slit, which is conducive to improving the accuracy of the light emission posture of the line light source 2 and the accuracy of the position of the second line slit, thereby improving the calibration accuracy of the optical path transmission module. Then, after each second line slit is arranged in the corresponding light-transmitting window 13, the line light beam emitted by the line light source 2 passes through the third line slit and the second line slit. Here, since in the second adjustment state, the third in-line slit can be located between the second in-line slit and the in-line light source 2, and the center of the light outlet of the in-line light source 2 is at the same height as the center line of the third in-line slit, then only if the light emission posture of the in-line light source 2 is basically the same as that in the first adjustment state, the in-line light beam emitted by the in-line light source 2 in the second adjustment state can pass through the third in-line slit, and then pass through the second in-line slit and the amplifying cavity 1. In this way, the third in-line slit can play a role in verifying the light emission posture of the in-line light source 2.

[0057] In the adjustment method of the optical transmission module provided by the present invention, in the entire second adjustment state, the position of the second optical element 4 can be fine-tuned so that the line light beam passes through the second line slit and the amplifying cavity 1. The fine-tuning here refers to the adjustment within the installation error range.

[0058] In the calibration method of the optical path transmission module provided by the present invention, the third optical element 5 can be placed before the line light source 2 is moved by a distance D, or the third optical element 5 can be placed after the line light source 2 is moved by a distance D, which is not limited in the present disclosure. If the third optical element 5 is placed before the line light source 2 is moved by a distance D, the third optical element 5 and the line light source 2 can be moved by a distance D in height at the same time.

[0059] In addition, in order to improve the adjustment accuracy and reduce or avoid the influence of the amplifying effect of the amplifying cavity 1 on the light, when each first single-line slit is arranged on the corresponding light-transmitting window 13, the amplifying cavity 1 can be in a power-off state to avoid amplifying the single-line light beam passing through the amplifying cavity 1; similarly, when each second single-line slit is arranged on the corresponding light-transmitting window 13, the amplifying cavity 1 can be in a power-off state to avoid amplifying the single-line light beam and seed light passing through the amplifying cavity 1.

[0060] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0061] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A calibration device for an optical transmission module, characterized in that: The optical path transmission module comprises a first reflecting element, a second reflecting element and an amplifying cavity of a laser located between the first reflecting element and the second reflecting element, wherein a first electrode and a second electrode are arranged opposite to each other in the amplifying cavity, and the first electrode and the second electrode are distributed in a height direction of the amplifying cavity; The amplifying cavity has two light-transmitting windows arranged opposite to each other, the adjusting device has a first adjusting state and a second adjusting state, and the adjusting device comprises: Two first optical elements having first straight-line slits, wherein in the first adjustment state, each of the first optical elements is disposed on the corresponding light-transmitting window, and a surface of the first electrode facing the second electrode is coplanar with a center line of the first straight-line slit; Two second optical elements with second straight-line slits, in the second adjustment state, each of the second optical elements is arranged on the corresponding light-transmitting window, and the center line of the second straight-line slit is coplanar with the center line of the first electrode and the second electrode in the height direction of the amplifying cavity; A line light source is located on one side of the amplifying cavity close to the first reflecting element, and is used to emit a line light beam passing through two of the first line slits and the amplifying cavity in the first adjustment state, and to emit a line light beam passing through two of the second line slits and the amplifying cavity in the second adjustment state.

2. The calibration device according to claim 1, characterized in that: In the first adjustment state, each of the first optical elements is detachably mounted on the corresponding light-transmitting window; in the second adjustment state, each of the second optical elements is detachably mounted on the corresponding light-transmitting window.

3. The calibration device according to claim 1, characterized in that: When the first optical element is disposed on the corresponding light-transmitting window, the geometric center of the first optical element is coaxial with the geometric center of the corresponding light-transmitting window, and the distance between the geometric center of the first optical element and the center line of the first straight-line slit is a; When the second optical element is disposed on the corresponding light-transmitting window, the geometric center of the second optical element is coaxial with the geometric center of the corresponding light-transmitting window, and the distance between the geometric center of the second optical element and the center line of the second straight-line slit is b; A height difference between the first adjustment state and the second adjustment state of the inline light source is D, and D=ab.

4. The calibration device according to claim 1, characterized in that: The width of the cross section of the line light beam provided by the line light source is less than or equal to the width of the first line slit; the width of the cross section of the line light beam provided by the line light source is less than or equal to the width of the second line slit, wherein, The line light source is a line light source with adjustable beam size, and / or the line light source is a line laser.

5. The adjustment device according to claim 1, characterized in that: The adjustment device also includes fluorescent paper. In the first adjustment state, the fluorescent paper is located between the second reflective element and one of the first optical elements close to the second reflective element. In the second adjustment state, the fluorescent paper is located between the second reflective element and one of the second optical elements close to the second reflective element.

6. The calibration device according to any one of claims 1 to 5, characterized in that: The adjustment device further comprises a third optical element having a third straight line slit; wherein, In the second adjustment state, the third optical element is located between one of the second line slits close to the line light source and the line light source, and the center of the light outlet of the line light source is at the same height as the center line of the third line slit; the line light beam emitted by the line light source in the second adjustment state is also used to pass through the third line slit; and / or, The third optical element is an adjustable mechanical slit; and / or, The width of the cross section of the inline light beam provided by the inline light source is less than or equal to the width of the third inline slit.

7. A method for calibrating an optical path transmission module, characterized in that: The calibration device according to any one of claims 1 to 6, wherein the calibration method comprises: Disposing each first optical element on the corresponding light-transmitting window; Adjusting the light emission posture of the inline light source so that the inline light source emits an inline light beam passing through the amplifying cavity and the two first inline slits; While keeping the light emission posture of the line light source constant, move the line light source by a distance D along the height increasing direction of the amplifying cavity; wherein D=ab, a is the distance between the geometric center of the first optical element and the center line of the first line slit; b is the distance between the geometric center of the second optical element and the center line of the second line slit; Remove the first optical element, and place each second optical element on the corresponding light-transmitting window; Using the line light source to emit a line light beam passing through the two second line slits and the amplifying cavity; The posture of the first reflecting element and / or the posture of the second reflecting element are adjusted to adjust the incident angle of the seed light entering the amplifying cavity using the first reflecting element and / or the second reflecting element, so that the seed light reflected by the second reflecting element passes through the amplifying cavity and the two second one-line slits.

8. The method for calibrating an optical transmission module according to claim 7, characterized in that: When the calibration device is the calibration device according to claim 6, after the line light source is used to emit a line light beam passing through the two first line slits and the amplifying cavity, the calibration method of the optical path transmission module further includes: The third optical element having the third line slit is placed between the amplifying cavity and the first reflecting element; the size of the third line slit is adjusted; and the line light beam emitted by the line light source is made to pass through the third line slit.

9. The method for calibrating an optical transmission module according to claim 8, characterized in that: The calibration method further includes: simultaneously moving the third optical element and the inline light source a distance D in height.

10. The method for calibrating an optical transmission module according to claim 7, wherein: Also includes: The second optical element is fine-tuned to make the line light beam pass through the second line slit and the amplifying cavity.

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