Device and method for measuring and calibrating position and direction of laser beam

Abstract

The invention discloses a laser beam position and direction measuring and calibrating device and method. The laser beam position and direction measuring device comprises a measuring box body, and a main light path, a beam position stability measuring device and a beam direction stability measuring device are arranged in the measuring box body; the main light path comprises a first lens and a beam splitter, a laser beam to be measured is transmitted to the beam splitter through the first lens, and the laser beam to be measured is divided into a first light beam and a second light beam through the beam splitter; the light beam position stability measuring device comprises a second lens, a first light source conversion element, a first imaging lens group and a first light beam detector which are sequentially arranged along the transmission direction of the first light beam; and the light beam pointing stability measuring device comprises a third lens, a second light source conversion element, a second imaging lens group and a second light beam detector which are sequentially arranged along the transmission direction of the second light beam. The device solves the problem that the measurement of the position stability and the pointing stability of the laser beam cannot meet the long-term measurement requirement.

Description

Technical Field

[0001] The present application relates to the field of optoelectronic technologies, and particularly to a laser beam position and pointing measurement device, a calibration device for laser beam position stability measurement results, a calibration device for laser beam pointing stability measurement results, and a laser beam position and pointing measurement method. Background Art

[0002] Laser technology has been widely applied in industries, agriculture, military, astronomy, and even our daily life. For example, laser pointers, laser burning, MP3 players, CD players, etc. are some of the most common laser products.

[0003] With the continuous in-depth research on lasers, the types of lasers are also increasing. In the development process of lasers or laser technology, the emergence of excimer lasers is an important milestone. An excimer laser source is a product developed on the basis of lasers. It is a laser with a short wavelength, a short pulse time, a wide laser spectrum, and a high power density. It uses the process of neutral particle-neutral molecule collisions involved in the generation of excited states in atoms or molecules in a gas, rather than the radiative transition of electrons to generate laser light. Therefore, excimer lasers have the characteristics of small volume, high energy, wide excitation energy levels, and higher control and stability, making them widely used in fields such as distance measurement, gas detection, biomedical applications, and communication. For example, semiconductor lithography, flat panel display manufacturing, ophthalmic refractive correction, thrombus ablation, etc.

[0004] During the propagation of a laser beam, it may be affected by factors such as mechanical vibration and the environment, resulting in changes in the position and pointing of the laser beam. Therefore, laser position stability and pointing stability are key factors to ensure the effective operation of lasers in various applications. Furthermore, the measurement of laser beam position stability and pointing stability is an important means to ensure the accuracy and stability of laser beams. Summary of the Invention

[0005] The present application provides a laser beam position and pointing measurement device to solve the technical problem in the prior art that the measurement of laser beam position stability and pointing stability cannot meet the long-term measurement requirements.

[0006] The present application provides a device for measuring the position and pointing of a laser beam, comprising: a measurement box body, wherein a main optical path, a beam position stability measurement device and a beam pointing stability measurement device are arranged inside the measurement box body; the main optical path includes: a first lens and a beam splitter, and the laser beam to be measured is transmitted to the beam splitter through the first lens, and the laser beam to be measured is divided into a first beam and a second beam by the beam splitter; the beam position stability measurement device includes a second lens, a first light source conversion element, a first imaging lens group and a first beam detector arranged in sequence along the transmission direction of the first beam, and the real image on the first light source conversion element is imaged on the first beam detector through the first imaging lens group to obtain the measurement result of the beam position stability; the beam pointing stability measurement device includes a third lens, a second light source conversion element, a second imaging lens group and a second beam detector arranged in sequence along the transmission direction of the second beam, and the real image on the second light source conversion element is imaged on the second beam detector through the second imaging lens group to obtain the measurement result of the beam pointing stability.

[0007] Optionally, according to the focal length of the first lens and the focal length of the second lens, the placement position of the second lens in the beam position stability measurement device is set; wherein, the focal length of the second lens is less than the focal length of the first lens.

[0008] Optionally, according to the focal point formed after the laser beam to be measured is focused by the first lens, which is located between the first focal length and the second focal length of the third lens, the placement position of the third lens in the beam pointing stability measurement device is set; wherein, the focal length of the third lens is less than the focal length of the first lens.

[0009] Optionally, the main optical path further includes: an attenuation sheet and a first steering mirror;

[0010] The incident surface of the attenuation sheet is opposite to the incoming light direction of the laser beam to be measured output by the laser, and is located between the laser and the first lens; the first steering mirror is arranged between the first lens and the beam splitter to control the direction of the beam in the main optical path; by adjusting the installation angle of the attenuation sheet, the energy of the laser beam to be measured entering the first light source conversion element and the first beam detector, and entering the second light source conversion element and the second beam detector is controlled.

[0011] Optionally, it further includes: a second steering mirror, which is located in the beam position stability measurement device or the beam pointing stability measurement device to control the direction of the first beam in the beam position stability measurement device and the direction of the second beam in the beam pointing stability measurement device, and the optical path lengths of the first beam in the beam position stability measurement device and the second beam in the beam pointing stability measurement device are the same;

[0012] When the second steering mirror is located in the beam pointing stability measurement device, the second steering mirror is arranged between the second light source conversion element and the third lens;

[0013] When the second steering mirror is located in the beam position stability measuring device, the second steering mirror is arranged between the first light source conversion element and the second lens.

[0014] Optionally, the distance from the first light source conversion element to the first imaging lens group is equal to the distance from the first beam detector to the first imaging lens group, and / or the distance from the second light source conversion element to the second imaging lens group is equal to the distance from the second beam detector to the second imaging lens group.

[0015] The present application also provides a calibration device for the measurement result of the laser beam position stability, including: a light source, a laser beam position and pointing measurement device, and a sliding guide rail; by controlling the movement of the light source or the laser beam position and pointing measurement device arranged on the sliding guide rail, the movement amount is used as the first calibration parameter; the change amount of the centroid on the first beam detector of the beam position stability measuring device in the laser beam position and pointing measurement device during the movement of the light source is used as the second calibration parameter; according to the first calibration parameter and the second calibration parameter, calibration data for adjusting the measurement result of the beam position stability is obtained.

[0016] The present application also provides a calibration device for the measurement result of the laser beam pointing stability, including: a light source, a sliding guide rail, a beam splitter, a focusing lens, a beam detector, and a laser beam position and pointing measurement device; the light output direction of the light source corresponds to the beam splitter and is arranged on the sliding guide rail; the beam splitter divides the light source into a first beam and a second beam; the light source is moved so that the first beam enters the laser beam position and pointing measurement device along the transmission direction, and through the beam pointing stability measuring device in the laser beam position and pointing measurement device, the first centroid change amount of the second beam detector in the beam pointing stability measuring device is obtained, and the second centroid change amount of the second beam along the transmission direction entering the focusing lens and then reaching the beam detector is obtained; according to the first centroid change amount and the second centroid change amount, calibration data for adjusting the measurement result of the beam pointing stability is obtained.

[0017] Optionally, it further includes: an attenuation sheet, the incident surface of the attenuation sheet faces the light output direction of the light source and is located between the beam splitter and the focusing lens.

[0018] The present application also provides a laser beam position and pointing measurement method, using the above-mentioned laser beam position and pointing measurement device to perform beam position stability measurement and beam pointing stability measurement.

[0019] The present application also provides a method for measuring the position and pointing of a laser beam, including: splitting the laser beam to be measured into a first beam and a second beam in the transmission direction according to a beam splitter in the main optical path; transmitting the first beam and the second beam to a beam position stability measuring device and a beam pointing stability measuring device respectively according to the transmission direction of the laser beam to be measured; obtaining a beam position stability measurement result of the laser beam to be measured according to the beam position stability measuring device; and obtaining a beam pointing stability measurement result of the laser beam to be measured according to the beam pointing stability measuring device.

[0020] Optionally, it further includes: correcting the beam position stability measurement result and / or the beam pointing stability measurement result.

[0021] Optionally, correcting the beam position stability measurement result and / or the beam pointing stability measurement result includes:

[0022] obtaining calibration data in a calibration device for the beam position stability measurement result of the laser beam;

[0023] correcting the beam position stability measurement result according to the calibration data and the beam position stability measurement result;

[0024] and / or,

[0025] obtaining calibration data in a calibration device for the beam pointing stability measurement result of the laser beam;

[0026] correcting the beam pointing stability measurement result according to the calibration data and the beam pointing stability measurement result.

[0027] The present application also provides a calibration method for the beam position stability measurement result of a laser beam, including: determining a first calibration parameter according to the moving amount of a light source or a laser beam position and pointing measuring device on a sliding guide; determining a second calibration parameter based on the movement of the light source or the laser beam position and pointing measuring device on the sliding guide according to the centroid change amount of the light source on a first beam detector of a beam position stability measuring device in the laser beam position and pointing measuring device; and determining calibration data for adjusting the beam position stability measurement result according to the first calibration parameter and the second calibration parameter.

[0028] The present application also provides a calibration method for the measurement results of the laser beam pointing stability, including: splitting the light source to obtain a first light beam and a second light beam transmitted along the transmission direction of the light source; according to the movement of the light source, obtaining the change amount of the first centroid on the second light beam detector in the beam pointing stability measurement device after the first light beam enters the laser beam position and pointing measurement device; according to the movement of the light source, obtaining the change amount of the second centroid on the light beam detector after the second light beam enters the focusing lens; and determining the calibration data for adjusting the measurement results of the beam pointing stability according to the change amount of the first centroid and the change amount of the second centroid.

[0029] Compared with the prior art, the present application has the following advantages:

[0030] The present application provides a laser beam position and pointing measurement device, including: a measurement box body, in which a main optical path, a beam position stability measurement device and a beam pointing stability measurement device are arranged; the main optical path includes: a first lens and a beam splitter, and the laser beam to be measured is transmitted to the beam splitter through the first lens, and the laser beam to be measured is split into a first light beam and a second light beam by the beam splitter; the beam position stability measurement device includes a second lens, a first light source conversion element, a first imaging lens group and a first light beam detector arranged in sequence along the transmission direction of the first light beam, and the real image on the first light source conversion element is imaged on the first light beam detector through the first imaging lens group to obtain the measurement result of the beam position stability; the beam pointing stability measurement device includes a third lens, a second light source conversion element, a second imaging lens group and a second light beam detector arranged in sequence along the transmission direction of the second light beam, and the real image on the second light source conversion element is imaged on the second light beam detector through the second imaging lens group to obtain the measurement result of the beam pointing stability.

[0031] The laser beam position and pointing measurement device of the present application includes a beam position stability measurement optical path and a beam pointing stability measurement optical path. The entire measurement device is only composed of a first lens, a beam splitter, a second lens, a first light source conversion element, a first imaging lens group, a first light beam detector, a third lens, a second light source conversion element, a second imaging lens group and a second light beam detector. The optical path design has a high integration degree, and the structure of the measurement device is simple. At the same time, the beam splitter is used to split the laser beam to be measured, and the laser beam to be measured is respectively divided into a position stability measurement optical path and a pointing stability measurement optical path. The two measurement lights after imaging through the first lens, the second lens, the first lens and the third lens are respectively incident on the light source conversion elements at corresponding positions for wavelength conversion, and finally the data is collected by the light beam detectors located at the ideal image planes of the imaging lens groups, thereby realizing the simultaneous measurement of the beam position and pointing stability, and the beam debugging is simple and efficient, meeting the requirements of long-term measurement of the beam position and pointing stability.

[0032] The laser beam position and pointing measurement device of the present application, through the beam position stability measurement device and the beam pointing stability measurement device, can meet the wavelength response range of ordinary beam detectors. It not only solves the disadvantages of short service life, low response, and easy damage of ordinary beam detectors in the current ultraviolet band, but also avoids the problem that the beam quality analyzer cannot meet the long-term measurement requirements of the beam position and pointing stability of high-repetition single-pulse laser beams due to low sampling frequency. Moreover, in the optical path design, it also solves the problems of separate and independent measurement of the beam position and pointing stability of the laser, low integration of the measurement device, cumbersome use, and low efficiency, realizing the simultaneous measurement of the beam position and beam pointing stability and improving the measurement efficiency.

[0033] The calibration device for the laser beam position stability measurement result of the embodiment of the present application can perform accuracy correction on the beam position stability measurement result of the beam position stability measurement device in the laser beam position and pointing measurement device. The calibration device for the laser beam pointing stability measurement result can perform accuracy correction on the beam pointing stability measurement result of the beam pointing stability measurement device in the laser beam position and pointing measurement device, so that the beam position stability measurement result of the beam position stability measurement device and the beam pointing stability measurement result of the beam pointing stability measurement device in the laser beam position and pointing measurement device are more accurate. Description of the Drawings

[0034] Figure 1a is a schematic structural diagram of the first embodiment of a laser beam position and pointing measurement device provided by the present application;

[0035] Figure 1b is a schematic structural diagram of the second embodiment of a laser beam position and pointing measurement device provided by the present application;

[0036] Figure 2 is a schematic structural diagram of the position stability measurement device in the first embodiment of a laser beam position and pointing measurement device provided by the present application;

[0037] Figure 3 is a schematic structural diagram of the pointing stability measurement device in the first embodiment of a laser beam position and pointing measurement device provided by the present application;

[0038] Figure 4a is a schematic structural diagram of the first embodiment of a calibration device for the laser beam position stability measurement result provided by the present application;

[0039] Figure 4b is a schematic structural diagram of the second embodiment of a calibration device for the laser beam position stability measurement result provided by the present application;

[0040] Figure 5It is a schematic structural diagram of a calibration device for the measurement result of the laser beam pointing stability provided by this application;

[0041] Figure 6 It is a flowchart of a method for measuring the laser beam position and pointing provided by this application;

[0042] Figure 7 It is a flowchart of a calibration method for the measurement result of the laser beam position stability provided by this application;

[0043] Figure 8 It is a flowchart of a calibration method for the measurement result of the laser beam pointing stability provided by this application;

[0044] Figure 9 It is a schematic diagram of an embodiment of a calibration method for the measurement result of the laser beam position stability provided by this application;

[0045] Figure 10 It is a schematic diagram of an embodiment of a calibration method for the measurement result of the laser beam pointing stability provided by this application.

[0046] Reference numerals: Laser beam position and pointing measurement device 100, measurement box body 101, main optical path 102, beam position stability measurement device 103, beam pointing stability measurement device 104;

[0047] The main optical path 102 includes: first lens 102-1, beam splitter 102-2, attenuation sheet 102-3, first turning mirror 102-4;

[0048] The beam position stability measurement device 103 includes: second lens 103-1, first light source conversion element 103-2, first imaging lens group 103-3, first beam detector 103-4;

[0049] The beam pointing stability measurement device 104 includes: third lens 104-1, second light source conversion element 104-2, second imaging lens group 104-3, second beam detector 104-4, second turning mirror 104-5;

[0050] The calibration device 105 for the measurement result of the laser beam position stability includes: light source 111, sliding guide rail 114, laser beam position and pointing measurement device 100;

[0051] The calibration device 106 for the measurement result of the laser beam pointing stability includes: light source 111, focusing lens 112, beam detector 113, sliding guide rail 114, laser beam position and pointing measurement device 100. Detailed implementation manners

[0052] In the following description, numerous specific details are set forth to provide a thorough understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the spirit of the present application. Therefore, the present application is not limited by the specific implementations disclosed below.

[0053] Based on the above background art, it can be known that the laser beam position and pointing measurement device provided by the present application can meet the long-term measurement requirements for the measurement of the position stability and pointing stability of the laser beam. Generally, the commonly used instruments for measuring the position and pointing stability of the laser beam are the position sensitive detector PSD (Position Sensitive Detector) or the quadrant detector QD (quad-rant detector), both of which are semiconductor position detection devices based on the lateral photoelectric effect and continuously distributed, and the wavelength response range is usually 400 - 1100 nm. Some are optimized in the ultraviolet band to make the wavelength reach 200 - 1100 nm, but the wavelength response range within 200 - 400 nm is generally <10%. At the same time, according to measurement experience, even if the PSD in the ultraviolet band can be used at 248 nm, its service life is very short, especially shorter under short pulses and high repetition frequencies, and it cannot meet the long-term reliability use in the deep ultraviolet band.

[0054] For excimer lasers, in order to improve the resolution and productivity of the chip, the wavelength of the laser is getting smaller, in the deep ultraviolet or extreme ultraviolet band, and the repetition frequency is getting higher, up to 6KHz. In this case, when measuring the position and pointing stability of the laser beam, ordinary PSDs cannot meet the requirements of long-term reliability measurement. Based on this, the currently commonly used method is to use a beam quality analyzer for measurement. However, on the one hand, because its sampling frequency is relatively low at 50Hz, it can only measure the integration result of a fixed exposure time (20ms). For a pulsed laser with a high repetition frequency of 6KHz, it cannot trace the centroid change of each pulse, and thus cannot meet the measurement requirements of the single-pulse position and pointing, lacking a substantial reference basis for judging the state of the laser (single-pulse energy) in the subsequent stage; on the other hand, because the beam quality analyzer is based on the pyroelectric principle, and the deep ultraviolet light has a short wavelength and large photon energy, especially when measuring the pointing stability, it is very easy to cause damage to the chip and data deviation due to heat accumulation.

[0055] Based on the prior art in the measurement of position and pointing stability, due to the optical path design, there are not only disadvantages such as low integration and poor data synchronization, but also problems such as complex optical path construction structure, cumbersome beam debugging, and low efficiency; therefore, in order to meet the long-term measurement requirements of beam position and pointing stability, a laser beam position and pointing measurement device provided by the present application will be described in detail below.

[0056] Such asFigure 1a and Figure 1b as shown in Figure 1a is a schematic structural diagram of a first embodiment of a laser beam position and pointing measurement device provided by the present application; Figure 1b is a schematic structural diagram of a second embodiment of a laser beam position and pointing measurement device provided by the present application.

[0057] The difference between the first embodiment and the second embodiment lies in the different layout methods of the beam position stability measurement device and the beam pointing stability measurement device in the laser beam position and pointing measurement device, which will be described in sequence below.

[0058] The laser beam position and pointing measurement device 100 according to the embodiment of the present application includes a measurement box body 101. Inside the measurement box body 101, there are provided a main optical path 102, a beam position stability measurement device 103, and a beam pointing stability measurement device 104. Among them, the beam position stability measurement device 103 is used to measure the position stability of the laser beam, and the beam pointing stability measurement device 104 is used to measure the pointing stability of the laser beam.

[0059] The main optical path 102 includes: a first lens 102-1 and a beam splitter 102-2. The first lens 102-1 and the beam splitter 102-2 are arranged in sequence along the beam transmission direction. The laser beam to be measured (light source 111) is transmitted to the beam splitter 102-2 through the first lens 102-1, and the laser beam to be measured is divided into a first beam and a second beam by the beam splitter 102-2. It should be noted that the first lens 102-1 is located in the main optical path 102, and can realize the dual imaging functions of position stability and pointing stability. Moreover, the first lens 102-1 is a long-focus lens, which is used to focus the laser beam to be measured to form a focal point. The beam splitter 102-2 is located between the first lens 102-1 and the second lens 103-1 (the third lens 104-1), and is used to split the beam output by the excimer light source to be measured, so as to realize the simultaneous measurement of the position stability optical path and the pointing stability optical path.

[0060] In this embodiment, when measuring the beam position stability, the beam position stability measuring device 103 includes a second lens 103-1, a first light source conversion element 103-2, a first imaging lens group 103-3, and a first beam detector 103-4 arranged in sequence along the first beam transmission direction. The real image on the first light source conversion element 103-2 is imaged on the first beam detector 103-4 through the first imaging lens group 103-3 to obtain the beam position stability measurement result. When measuring the beam pointing stability, the beam pointing measuring device 104 includes a third lens 104-1, a second light source conversion element 104-2, a second imaging lens group 104-3, and a second beam detector 104-4 arranged in sequence along the second beam transmission direction. The real image on the second light source conversion element 104-2 is imaged on the second light speed detector 104-4 through the second imaging lens group 104-3 to obtain the beam pointing stability measurement result.

[0061] It should be noted that in the optical path design, for the beam position stability measuring device 103, the placement position of the second lens 103-1 in the beam position stability measuring device 103 is set according to the focal lengths of the first lens 102-1 and the second lens 103-1. Specifically, in the design, the distance between the second lens 103-1 and the first lens 102-1 is the sum of the focal lengths of the second lens 103-1 and the first lens 102-1, where the focal length of the second lens 103-1 is less than the focal length of the first lens 102-1. For the beam pointing stability measuring device 104, the placement position of the third lens 104-1 in the beam pointing stability measuring device 104 is set according to the position where the focus formed after the laser beam to be measured is focused by the first lens 102-1 is between the first focal length and the second focal length of the third lens 104-1. Among them, the focal length of the third lens 104-1 is less than the focal length of the first lens 102-1.

[0062] In this embodiment, the second lens 103-1 and the third lens 104-1 are lenses of the same specification, and the first lens 102-1 is a long-focus lens, while the second lens 103-1 and the third lens 104-1 are both short-focus lenses, and the length of the focal length is relative. The materials of the first lens 102-1, the second lens 103-1, and the third lens 104-1 are fused silica and calcium fluoride (CaF 2), so as to ensure that the first lens 102-1, the second lens 103-1, and the third lens 104-1 have a high transmittance under ultraviolet light. The focal lengths of the first lens 102-1, the second lens 103-1, and the third lens 104-1 can be selected according to the actual optical path and design purpose. Moreover, since the focal length of a lens is related to the refractive index of the material, and the refractive index of the material changes with the change of the incident light frequency (wavelength), therefore, the focal lengths of the first lens 102-1, the second lens 103-1, and the third lens 104-1 change with the wavelength of the excimer laser, and precise calculations need to be performed according to the wavelength size during actual optical path measurement.

[0063] In this embodiment, the first light source conversion element 103-2 and the second light source conversion element 104-2 are used to convert a beam with a higher frequency (shorter wavelength) into a beam with a lower frequency (longer wavelength). For example, ultraviolet light is converted into visible light. The first light source conversion element 103-2 and the second light source conversion element 104-2 can adopt fluorescent glass. Among them, the principle of fluorescent glass is to emit visible light fluorescence through the interaction of ultraviolet light and fluorescent substances. Different ions doped on the glass or crystal and different ion concentrations will emit visible light with different wavelengths. The fluorescent glass can be glass or crystal, and any rare earth ions can be doped therein to achieve the ability to convert ultraviolet light into visible light. Moreover, a band-pass filter can be added behind the first light source conversion element 103-2 and the second light source conversion element 104-2 to filter out unnecessary stray light.

[0064] In this embodiment, the first light source conversion element 103-2 and the second light source conversion element 104-2 are provided mainly because the fluorescent glass is used to convert ultraviolet light into visible light, so as to indirectly measure the stability of the ultraviolet light beam by measuring the beam position and pointing stability of the visible light. The reason for converting ultraviolet light into visible light for measurement is mainly as follows: on the one hand, the commonly used instruments for measuring the position and pointing stability of laser beams are the position sensitive detector PSD (Position Sensitive Detector) or the quadrant detector QD (quad-rant detector). Both of them are semiconductor position detection devices based on the lateral photoelectric effect and continuous distribution, and the wavelength response range is usually 400-1100nm. Some are optimized in the ultraviolet band to make their wavelength reach 200-1100nm, but the wavelength response range within 200-400nm is generally <10%. At the same time, according to measurement experience, even if the PSD in the ultraviolet band can be used at 248nm, its service life is very short, especially shorter under short pulses and high repetition frequencies, and it cannot meet the long-term reliability use in the deep ultraviolet band; on the other hand, for excimer lasers, in order to improve the resolution and yield of the chip, the wavelength of the laser is getting smaller, in the deep ultraviolet or extreme ultraviolet band, and the repetition frequency is getting higher, up to 6KHz. In this case, when measuring the position and pointing stability of the laser beam, the ordinary PSD cannot meet the requirements of long-term reliability measurement. The commonly used method at present is to use a beam quality analyzer for measurement. However, on the one hand, because its sampling frequency is relatively low at 50Hz, it can only measure the integration result of a fixed exposure time (20ms). For a pulsed laser with a high repetition frequency of 6KHz, the beam quality analyzer cannot trace the centroid change of each pulse. Therefore, the beam quality analyzer cannot meet the measurement requirements of the single-pulse position and pointing; on the other hand, because the beam quality analyzer is based on the pyroelectric principle, and the deep ultraviolet light has a short wavelength and high photon energy, especially when measuring the pointing stability, it is easy to cause damage to the chip and data deviation due to heat accumulation. Therefore, in this embodiment, by using fluorescent glass to convert the ultraviolet light with a short wavelength into visible light with a long wavelength, the wavelength response range of the ordinary PSD can be satisfied, which not only solves the disadvantages of short service life, low response, high price and easy damage of the PSD in the current ultraviolet band, but also avoids the inability of the beam quality analyzer to meet the long-term reliability measurement of the single-pulse position and pointing at high repetition frequencies.

[0065] In specific implementation, the main optical path 102 further includes: an attenuation sheet 102-3 and a first steering mirror 102-4; the incident surface of the attenuation sheet 102-3 faces the incoming light direction of the laser beam to be measured output by the laser, and is located between the laser and the first lens 102-1; the first steering mirror 102-4 is disposed between the first lens 102-1 and the beam splitter 102-2; by adjusting the installation angle of the attenuation sheet 102-3, the energy of the laser beam to be measured entering the first light source conversion element 103-2 and the first beam detector 103-4, as well as entering the second light source conversion element 104-2 and the second beam detector 104-4, is controlled. In specific implementation, one or more attenuation sheets 102-3 can be set according to the energy scenario requirements of the laser beam to be attenuated, and specifically, an ultraviolet attenuation sheet can be selected. For example, in this embodiment, taking the setting of two attenuation sheets as an example, a first ultraviolet attenuation sheet and a second ultraviolet attenuation sheet. The first ultraviolet attenuation sheet and the second ultraviolet attenuation sheet are sequentially disposed between the laser and the first lens 102-1, and the incident surface of the first ultraviolet attenuation sheet faces the incoming light direction of the laser beam to be measured output by the laser. The materials of the first ultraviolet attenuation sheet and the second ultraviolet attenuation sheet are fused silica or CaF 2 . The first beam detector 103-4 and the second beam detector 104-4 can specifically be position sensitive detectors PSD, and generally, ordinary PSDs are selected, with a wavelength range of 400-1100 nm. The high-speed acquisition board card supporting the PSD is a customized structure for matching the Burst mode of the excimer laser. The wavelength selection of the PSD is related to the wavelength at which the fluorescent glass is converted into visible light.

[0066] It should be noted that the setting of the attenuation sheet 102-3 can be made according to the actual measurement scenario requirements. For example, when the energy of the excimer laser is relatively strong, the energy of the laser beam to be measured can be attenuated by setting the attenuation sheet 102-3 to avoid damage to the fluorescent glass and PSD caused by the laser beam to be measured. Of course, in this embodiment, the case where the energy of the laser is relatively strong is taken as an example for illustration, and it does not exclude the situation where the fluorescent glass and PSD will not be damaged and the attenuation sheet does not need to be set. The reason for setting the attenuation sheet 102-3 in the main optical path 102 of the laser beam position and pointing measurement device 100 of the present application is mainly that the energy of the excimer laser is relatively strong. In order to avoid damage to the fluorescent glass and PSD caused by the light source to be measured, a first ultraviolet attenuation sheet and a second ultraviolet attenuation sheet are added to the measurement device. The attenuation sheet 102-3 is used to attenuate the energy of the laser beam to be measured to ensure that the beam energy is attenuated to within the damage thresholds of the fluorescent glass and PSD. The installation angles of the first ultraviolet attenuation sheet and the second ultraviolet attenuation sheet are determined by the signal-to-noise ratio and damage threshold of the PSD. By adjusting the installation angles of the first ultraviolet attenuation sheet and the second ultraviolet attenuation sheet, the energy size entering the fluorescent glass and PSD is changed, so as to determine an appropriate signal-to-noise ratio and avoid the signal being too weak or oversaturated.

[0067] In this embodiment, the main optical path 102 further includes: a first steering mirror 102-4 for deflecting the optical path, and the first steering mirror 102-4 is disposed between the first lens 102-1 and the beam splitter 102-2. During the specific optical path design, it further includes: a second steering mirror 104-5 located in the beam position stability measuring device 103 or the beam pointing stability measuring device 104 for controlling the direction of the first beam in the beam position stability measuring device 103 and the direction of the second beam in the beam pointing stability measuring device 104, and the optical paths of the first beam in the beam position stability measuring device 103 and the second beam in the beam pointing stability measuring device 104 are the same.

[0068] It should be noted that during the specific optical path design, the second steering mirror 104-5 is disposed in the beam position stability measuring device 103 or the beam pointing stability measuring device 104. For details, please refer to Figure 1a and Figure 1b , Figure 1a wherein the second steering mirror 104-5 is disposed in the beam pointing stability measuring device 104 and is disposed between the second light source conversion element 104-2 and the third lens 104-1; Figure 1b wherein the second steering mirror 104-5 is disposed in the beam position stability measuring device 103 and is disposed between the first light source conversion element 103-2 and the second lens 103-1. The first steering mirror 102-4 and the second steering mirror 104-5 may specifically be refractive mirrors, and the materials of the first steering mirror 102-4 and the second steering mirror 104-5 may be high-reflection mirrors coated with dielectric films or metal films. The first steering mirror 102-4 and the second steering mirror 104-5 are not only used for deflecting the optical path and compressing the spatial volume, but also ensure that the optical paths of the first beam in the beam position stability measuring device 103 and the second beam in the beam pointing stability measuring device 104 are the same, thereby improving the portability of the measuring device.

[0069] In this embodiment, the distance from the first light source conversion element 103-2 to the first imaging lens group 103-3 is equal to the distance from the first light beam detector 103-4 to the first imaging lens group 103-3, and / or the distance from the second light source conversion element 104-2 to the second imaging lens group 104-3 is equal to the distance from the second light beam detector 104-4 to the second imaging lens group 104-3. Specifically, in implementation, the first light beam detector 103-4 can be arranged at the ideal focal plane of the first light source conversion element 103-2, and the second light beam detector 104-4 can be arranged at the ideal focal plane of the second light source conversion element 104-2. The first imaging lens group 103-3 and the second imaging lens group 104-3 can specifically be relay lens groups, which are used to relay image the light field on the fluorescent glass onto the PSD. The imaging ratio of the relay lens group is 1:1. The wavelength selection of the relay lens group is related to the wavelength at which the fluorescent glass is converted into visible light. The antireflection film range selected for the relay lens group is the 400-700nm band.

[0070] It should be noted that in the specific optical path design, in one way, the distance from the first light source conversion element 103-2 to the first imaging lens group 103-3 and the distance from the first light beam detector 103-4 to the first imaging lens group 103-3 can be set to an equal relationship, and the relationship between the distance from the second light source conversion element 104-2 to the second imaging lens group 104-3 and the distance from the second light beam detector 104-4 to the second imaging lens group 104-3 is not limited; in one way, the distance from the second light source conversion element 104-2 to the second imaging lens group 104-3 and the distance from the second light beam detector 104-4 to the second imaging lens group 104-3 can be set to an equal relationship, and the relationship between the distance from the first light source conversion element 103-2 to the first imaging lens group 103-3 and the distance from the first light beam detector 103-4 to the first imaging lens group 103-3 is not limited; there is also one way that the distance from the first light source conversion element 103-2 to the first imaging lens group 103-3, the distance from the first light beam detector 103-4 to the first imaging lens group 103-3, the distance from the second light source conversion element 104-2 to the second imaging lens group 104-3, and the distance from the second light beam detector 104-4 to the second imaging lens group 104-3 can all be set to an equal relationship. Of course, for the beauty of the mechanical mechanism, the last way above is adopted in the embodiment of the present application. Specifically, in implementation, it can be set according to the actual measurement scenario requirements, and all are within the protection scope of the embodiment of the present application.

[0071] In this embodiment, the measurement box body 101 is connected to the laser beam generator to be measured through a flange, so as to ensure that the entire measurement device is in a sealed state. Moreover, a nitrogen gas hole is provided at the bottom of the measurement box body 101, and nitrogen gas is input into the measurement box body 101 through the nitrogen gas hole, ensuring that the main optical path, the beam position stability measurement device, and the beam pointing stability measurement device are sealed in an environment filled with high-purity nitrogen gas to protect the optical path components.

[0072] The above is the description of the laser beam position and pointing measurement device in the embodiment of the present application. Next, the measurement principle of the laser beam position and pointing measurement device will be described.

[0073] When measuring the position stability of the excimer laser to be measured in this embodiment, the beam position stability measurement device 103 is used, and the measurement principle is as Figure 2 shown. Figure 2 FIG. 10 is a schematic structural diagram of the position stability measurement device in the first embodiment of the laser beam position and pointing measurement device provided by the present application. The laser beam to be measured is imaged through the first lens 102-1 and the second lens 103-1. The distance between the first lens 102-1 and the second lens 103-1 is the sum of the focal lengths of the two lenses. Then, the real image on the first light source conversion element 103-2 is imaged on the first beam detector 103-4 through the first imaging lens group 103-3, thereby obtaining the measurement result of the beam position stability.

[0074] It should be noted that the beam expander (shrinker) system is a system that can proportionally expand (shrink) the diameter of the collimated input beam and is commonly used in laser scanning, interferometric measurement, or telemetry applications. In the field of laser measurement, the common ones are the Kepler structure and the Galileo structure. The Kepler structure consists of two positive lenses. The distance between the two positive lenses is equal to the sum of the focal lengths of the two positive lenses. The output beam is inverted relative to the input beam, and there is a focal plane in the middle, which can form an inverted and reduced real image. The Galileo structure consists of a negative lens and a positive lens. The distance between the two lenses is equal to the difference between the focal lengths of the two lenses. The combination of the positive and negative lenses will not invert the direction of the beam, so it will not form an inverted image.

[0075] In order to reduce the beam of the laser to be measured to match the PSD target surface, the beam position stability measurement device 103 adopts a Kepler structure, aiming to form an inverted and reduced real image on the first light source conversion element 103-2 and ensure that the beam exits parallel. By using the principle of forming an inverted and reduced real image with the Kepler structure, the focal length of the first lens 102-1 is greater than the focal length of the second lens 103-1, and the distance between the first lens 102-1 and the second lens 103-1 is the sum of the focal lengths of the two lenses, ensuring that the beam is reduced and exits parallel. The reduction ratio is the ratio of the focal lengths of the two lenses. Then, a first imaging lens group 103-3 with a 1:1 imaging ratio is used to image the inverted and reduced real image on the first light source conversion element 103-2 into an upright and equal-sized real image at the target surface of the first beam detector 103-4, thereby realizing the measurement of the beam position stability.

[0076] When measuring the pointing stability of the excimer laser to be measured in this embodiment, the beam pointing stability measurement device 104 is used, and the measurement principle is as Figure 3 shown, Figure 3 which is a schematic structural diagram of the pointing stability measurement device in the first embodiment of a laser beam position and pointing measurement device provided by this application. After the laser beam to be measured passes through the first lens 102-1 for focusing, the light spot at the focal point is the light spot for which the pointing stability is to be measured. Considering the processing technology and mechanical alignment problems, the light spot at the focal point needs to be imaged twice. By using the principle of forming an inverted and enlarged real image between one focal length and two focal lengths, the focal point is located between one focal length and two focal lengths of the third lens 104-1. The size of the image is related to the position of the image plane (the second light source conversion element 104-2). Then, a second imaging lens group 104-3 with a 1:1 imaging ratio is used to image the inverted real image on the second light source conversion element 104-2 into an upright and equal-sized real image at the target surface of the second beam detector 104-4, thereby realizing the measurement of the pointing stability.

[0077] In this embodiment, when measuring the position stability of the laser beam to be measured by using the beam position stability measuring device 103, the inverted and reduced real image located on the first light source conversion element 103-2 is imaged as an upright and equal-sized real image on the target surface of the first beam detector 103-4 through the first imaging lens group 103-3; when measuring the pointing stability of the laser beam to be measured by using the beam position pointing measuring device 104, the inverted real image located on the second light source conversion element 104-2 is imaged as an upright and equal-sized real image on the target surface of the second beam detector 104-4 through the second imaging lens group 104-3. It should be noted that the first beam detector 103-4 and the second beam detector 104-4 may specifically be position-sensitive detectors PSD. PSD is an optoelectronic device sensitive to the centroid position of the incident light spot on its photosensitive surface. When the incident light spot falls on different positions of the device photosensitive surface, PSD will correspondingly output different electrical signals. By processing the output signals, the position of the centroid of the incident light spot on PSD can be determined. The signal size detected by PSD has nothing to do with the intensity, size and distribution of the incident light spot, and only relates to the energy centroid position of the incident light. The beam position stability measurement result or the beam pointing stability measurement result refers to the result of statistically analyzing the change in the centroid position x of the light spot of the laser pulse on the PSD target surface. Since different evaluation indexes have different calculation methods, it is usually 3 times the standard deviation. Among them, the centroid position x of the light spot of the laser pulse on the PSD target surface is calculated in the following way:

[0078]

[0079] Wherein, X 1 、X 2 are current signals, and L is the size of the PSD target surface.

[0080] It should be noted that, for the sake of the beauty of the mechanical structure, in this embodiment, the beam splitter 102-2 divides the laser beam to be measured into two paths. One path is used for measuring the beam position stability, and the other is used for measuring the beam pointing stability. The second steering mirror 104-5 in the beam pointing stability measuring device 104 is used to realize the optical path folding, so that the first light source conversion element 103-2 in the beam position stability measuring device 103 and the second light source conversion element 104-2 in the beam pointing stability measuring device 104 are on the same horizontal plane. Since the size of the image formed in the beam pointing stability measuring device 104 is related to the position of the image plane (the second light source conversion element 104-2), the beam expansion ratio in the beam pointing stability measuring device 104 is related to the position of the second light source conversion element 104-2. Also, because the first light source conversion element 103-2 in the beam position stability measuring device 103 and the second light source conversion element 104-2 in the beam pointing stability measuring device 104 are on the same horizontal plane, once the position of the first light source conversion element 103-2 in the beam position stability measuring device 103 is fixed, the position of the second light source conversion element 104-2 in the beam pointing stability measuring device 104 can be determined, and further the beam expansion ratio of the beam pointing stability measuring device can be determined.

[0081] The above is a description of a specific embodiment of a laser beam position and pointing measurement device provided by the present application. Through the beam position stability measuring device and the beam pointing stability measuring device, the wavelength response range of a common beam detector can be satisfied. It not only solves the disadvantages of short service life, low response, and easy damage of common beam detectors in the current ultraviolet band, but also avoids the problem that the beam quality analyzer cannot meet the long-term measurement requirements of the position and pointing stability of high-repetition-rate single-pulse laser beams due to low sampling frequency. Moreover, in the optical path design, it also solves the problems existing in the prior art, such as low integration, poor data synchronization, complex optical path construction structure, cumbersome beam debugging, and low efficiency, during the measurement of position and pointing stability.

[0082] In view of the deviation in the optical path alignment during the simulation and actual optical path measurements of the laser beam position and pointing measurement device provided by the present application, which results in deviations in the beam reduction ratio of the actual position measurement optical path and the beam expansion ratio of the pointing measurement optical path, it is necessary to calibrate the laser beam position and pointing measurement device 100 of the simulation optical path before using the simulation optical path measurement. The following describes a calibration device for the measurement result of laser beam position stability and a calibration device for the measurement result of laser beam pointing stability.

[0083] The present application provides a calibration device for the measurement result of laser beam position stability. Please refer to Figure 4a and Figure 4b , Figure 4aIt is a schematic structural diagram of the first embodiment of a calibration device for the measurement result of the laser beam position stability provided by this application; Figure 4b It is a schematic structural diagram of the second embodiment of a calibration device for the measurement result of the laser beam position stability provided by this application. The calibration device for the measurement result of the laser beam position stability includes: a light source 111, a laser beam position and pointing measurement device 100, and a sliding guide rail 114; by controlling the movement of the light source 111 or the laser beam position and pointing measurement device 100 arranged on the sliding guide rail 114, the movement amount is used as the first calibration parameter; the centroid change amount of the light source 111 on the first beam detector 103-4 of the beam position stability measurement device in the laser beam position and pointing measurement device 100 during the movement process is used as the second calibration parameter; according to the first calibration parameter and the second calibration parameter, calibration data for adjusting the measurement result of the beam position stability is obtained.

[0084] It should be noted that in the calibration device for the measurement result of the laser beam position stability, one way is to place the light source 111 on the sliding guide rail 114. Please refer to Figure 4a , according to the movement amount of the sliding guide rail 114, that is, the first calibration parameter, actually measure the centroid change amount of the light source 111 on the first beam detector 103-4 of the beam position stability measurement device in the laser beam position and pointing measurement device 100, that is, the first calibration parameter, and then fit the first calibration parameter and the second calibration parameter to obtain the calibration data for adjusting the measurement result of the beam position stability, that is, obtain the calibration coefficient K1. The calibration coefficient K1 is used to correct the measurement result of the beam position stability, thereby improving the accuracy. In another way, of course, the laser beam position and pointing measurement device 100 can also be placed on the sliding guide rail 114 for measurement. Please refer to Figure 4b . In other words, for the calibration device for the measurement result of the laser beam position stability, both the light source 111 and the laser beam position and pointing measurement device 100 can be arranged on the sliding guide rail 114, with either one being the movable end and the other being the fixed end.

[0085] This application provides a calibration device for the measurement result of the laser beam pointing stability. Please refer to Figure 5 , Figure 5It is a schematic structural diagram of a calibration device for the measurement result of the laser beam pointing stability provided by this application; the calibration device for the measurement result of the laser beam pointing stability includes: a light source 111, a sliding guide rail 114, a beam splitter 102-2, a focusing lens 112, a beam detector 113, and a laser beam position and pointing measurement device 100; the light-emitting direction of the light source 111 corresponds to the beam splitter 102-2 and is arranged on the sliding guide rail 114; the beam splitter 102-2 divides the light source 111 into a first beam and a second beam; move the light source 111 so that the first beam enters the laser beam position and pointing measurement device 100 along the transmission direction, and through the beam pointing stability measurement device 103 in the laser beam position and pointing measurement device 100, obtain the first centroid change amount of the second beam detector 104-4 in the beam pointing stability measurement device 103, and the second centroid change amount of the second beam entering the focusing lens 112 along the transmission direction and then reaching the beam detector 113; according to the first centroid change amount and the second centroid change amount, obtain the calibration data for adjusting the measurement result of the beam pointing stability. Specifically in implementation, by moving the light source 11 on the sliding guide rail 114 and simultaneously measuring the first centroid change amount of the second beam detector 104-4 in the beam pointing stability measurement device 103 and the second centroid change amount on the beam detector 113 within a period of time, and by fitting the first centroid change amount and the second centroid change amount, the calibration data for adjusting the measurement result of the beam pointing stability can be obtained, that is, the calibration coefficient K2 is obtained. The calibration coefficient K2 is used to correct the measurement result of the beam pointing stability, thereby improving the accuracy. Among them, for the specific process of obtaining K1 and K2 by fitting, for example, linear fitting can be performed to obtain the slope as the calibration coefficient, which will not be described in detail here.

[0086] It should be noted that in order to avoid the deviation caused by the asynchronous measurement of the light source 111, a beam splitter 102-2 is provided in the calibration device for the measurement result of the laser beam pointing stability. The beam splitter 102-2 divides the light source 111 into two paths. One path of the beam is transmitted to the laser beam position and pointing measurement device 100, and one path of the beam is transmitted to the beam detector 113. Among them, the beam detector 113 can specifically be an ultraviolet position-sensitive detector PSD or a beam quality analyzer PY-4, which is used to measure the average value of the centroid change amount within a period of time. Similarly, in order to avoid damage to the beam detector 113 caused by the beam energy, an attenuation sheet 102-3 is also provided in the calibration device for the measurement result of the laser beam pointing stability. The incident surface of the attenuation sheet 102-3 faces the light-emitting direction of the light source 111 and is located between the beam splitter 102-2 and the focusing lens 112. The material of the focusing lens 112 is CaF 2Or fused silica, try to select a lens with a large focal length. The focal length of the focusing lens 112 is generally greater than 800 mm to reduce measurement errors. Moreover, the beam detector 113 is located at the ideal focal plane of the focusing lens 112 to ensure that the formed image matches the PSD target surface. Among them, the light source 111 and the laser beam to be measured in the above laser beam position and pointing measurement device 100 are the same light source, such as Figure 9 and Figure 10 shown Figure 9 is a schematic diagram of an embodiment of a calibration method for the measurement result of the laser beam position stability provided by this application, Figure 10 is a schematic diagram of an embodiment of a calibration method for the measurement result of the laser beam pointing stability provided by this application.

[0087] The above is the description of the calibration device for the measurement result of the laser beam position stability and the calibration device for the measurement result of the laser beam pointing stability. By calibrating the measurement result with the calibration device, the measurement result can be corrected, thereby improving the measurement accuracy. The following describes a laser beam measurement method.

[0088] This application provides a method for measuring the position and pointing of a laser beam. Please refer to Figure 6 , Figure 6 which is a flowchart of a method for measuring the position and pointing of a laser beam provided by this application.

[0089] Step S601: Divide the laser beam to be measured into a first beam and a second beam in the transmission direction according to the beam splitter in the main optical path.

[0090] This step is used to divide the laser beam to be measured into a first beam and a second beam in the transmission direction according to the beam splitter in the main optical path.

[0091] Step S602: Transmit the first beam and the second beam to the laser beam position stability measurement device and the laser beam pointing stability measurement device respectively according to the transmission direction of the laser beam to be measured.

[0092] This step is used to transmit the first beam to the laser beam position stability measurement device and the second beam to the laser beam pointing stability measurement device.

[0093] Step S603: Obtain the measurement result of the laser beam position stability of the laser beam to be measured according to the laser beam position stability measurement device.

[0094] This step is used to obtain the measurement result of the laser beam position stability of the laser beam to be measured according to the laser beam position stability measurement device.

[0095] Step S604: Obtain the measurement result of the laser beam pointing stability of the laser beam to be measured according to the laser beam pointing stability measurement device.

[0096] This step is used to obtain the measurement result of the beam pointing stability of the laser beam to be measured according to the beam pointing stability measurement device.

[0097] It should be noted that in this embodiment, the process of obtaining the measurement result of the beam position stability of the laser beam to be measured according to the beam position stability measurement device and the process of obtaining the measurement result of the beam pointing stability of the laser beam to be measured according to the beam pointing stability measurement device have been described in detail in the above embodiments, and will not be elaborated here. For the specific process, please refer to the relevant content of the above embodiments.

[0098] In this embodiment, after obtaining the measurement result of the beam position stability and the measurement result of the beam pointing stability, it further includes: correcting the measurement result of the beam position stability and / or the measurement result of the beam pointing stability. Correcting the measurement result of the beam position stability and / or the measurement result of the beam pointing stability includes: obtaining the calibration data in the calibration device for the measurement result of the laser beam position stability; correcting the measurement result of the beam position stability according to the calibration data and the measurement result of the beam position stability; and / or, obtaining the calibration data in the calibration device for the measurement result of the laser beam pointing stability; correcting the measurement result of the beam pointing stability according to the calibration data and the measurement result of the beam pointing stability. Specifically, when implementing, correcting the measurement result of the beam position stability according to the calibration data and the measurement result of the beam position stability can specifically be multiplying the measurement result of the beam position stability by a calibration coefficient to correct the measurement result of the beam position stability so as to improve the measurement accuracy; correcting the measurement result of the beam pointing stability according to the calibration data and the measurement result of the beam pointing stability can specifically be multiplying the measurement result of the beam pointing stability by a calibration coefficient to correct the measurement result of the beam pointing stability.

[0099] It should be noted that the calibration data in the calibration device for the measurement result of the laser beam position stability in this embodiment has been described in detail in the above embodiments; the obtaining method of the calibration data in the calibration device for the measurement result of the laser beam pointing stability has also been described in detail in the above embodiments, and will not be elaborated here. For the specific obtaining process, please refer to the above relevant content.

[0100] The present application provides a calibration method for the measurement result of the laser beam position stability. Please refer to Figure 7 , Figure 7 which is a flowchart of a calibration method for the measurement result of the laser beam position stability provided by the present application.

[0101] Step S701: Determine the first calibration parameter according to the movement amount of the light source or the laser beam position and pointing measurement device on the sliding guide rail;

[0102] Step S702: Based on the movement of the light source or the laser beam position and pointing measurement device on the sliding guide rail, determine the second calibration parameter according to the change in the centroid on the first beam detector of the beam position stability measurement device in the laser beam position and pointing measurement device;

[0103] Step S703: Determine the calibration data for adjusting the beam position stability measurement result according to the first calibration parameter and the second calibration parameter.

[0104] This application provides a calibration method for the measurement result of the laser beam pointing stability. Please refer to Figure 8 , Figure 8 which is the flowchart of a calibration method for the measurement result of the laser beam pointing stability provided by this application.

[0105] Step S801: Split the light source to obtain a first beam and a second beam transmitted along the transmission direction of the light source;

[0106] Step S802: According to the movement of the light source, obtain the first centroid change amount on the second beam detector in the beam pointing stability measurement device after the first beam enters the laser beam position and pointing measurement device;

[0107] Step S803: According to the movement of the light source, obtain the second centroid change amount on the beam detector after the second beam enters the focusing lens;

[0108] Step S804: Determine the calibration data for adjusting the beam pointing stability measurement result according to the first centroid change amount and the second centroid change amount.

[0109] Although this application is disclosed above with preferred embodiments, it is not intended to limit this application. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of this application. Therefore, the protection scope of this application should be defined by the scope of the claims of this application.

Claims

1. A laser beam position and pointing measurement device, characterized in that, it includes: a measurement box body, inside which a main optical path, a beam position stability measurement device and a beam pointing stability measurement device are arranged; The main optical path includes: a first lens and a beam splitter. The laser beam to be measured is transmitted to the beam splitter through the first lens, and the laser beam to be measured is divided into a first beam and a second beam by the beam splitter; The beam position stability measurement device includes a second lens, a first light source conversion element, a first imaging lens group and a first beam detector arranged in sequence along the transmission direction of the first beam. The real image on the first light source conversion element is imaged on the first beam detector through the first imaging lens group to obtain the beam position stability measurement result; The beam pointing stability measurement device includes a third lens, a second light source conversion element, a second imaging lens group and a second beam detector arranged in sequence along the transmission direction of the second beam. The real image on the second light source conversion element is imaged on the second beam detector through the second imaging lens group to obtain the beam pointing stability measurement result.

2. The laser beam position and pointing measurement device according to claim 1, characterized in that, the placement position of the second lens in the beam position stability measurement device is set according to the focal length of the first lens and the focal length of the second lens; wherein, the focal length of the second lens is less than the focal length of the first lens.

3. The laser beam position and pointing measurement device according to claim 1, characterized in that, the placement position of the third lens in the beam pointing stability measurement device is set according to the position where the focus formed after the laser beam to be measured is focused by the first lens is between the first focal length and the second focal length of the third lens; wherein, the focal length of the third lens is less than the focal length of the first lens.

4. The laser beam position and pointing measurement device according to claim 1, characterized in that, the main optical path further includes: an attenuation sheet and a first steering mirror; The incident surface of the attenuation sheet is opposite to the incoming light direction of the laser beam to be measured output by the laser, and is located between the laser and the first lens; the first steering mirror is arranged between the first lens and the beam splitter to control the direction of the beam in the main optical path; by adjusting the installation angle of the attenuation sheet, the energy of the laser beam to be measured entering the first light source conversion element and the first beam detector, and entering the second light source conversion element and the second beam detector is controlled.

5. The laser beam position and pointing measurement device according to claim 1, characterized in that, it further includes: The second steering mirror is located in the beam position stability measurement device or the beam pointing stability measurement device, and is used to control the direction of the first beam in the beam position stability measurement device and the direction of the second beam in the beam pointing stability measurement device, and the optical paths of the first beam in the beam position stability measurement device and the second beam in the beam pointing stability measurement device are the same; When the second steering mirror is located in the beam pointing stability measurement device, the second steering mirror is arranged between the second light source conversion element and the third lens; When the second steering mirror is located in the beam position stability measurement device, the second steering mirror is arranged between the first light source conversion element and the second lens.

6. The laser beam position and pointing measurement device according to claim 1, wherein, the distance from the first light source conversion element to the first imaging lens group is equal to the distance from the first beam detector to the first imaging lens group, and / or the distance from the second light source conversion element to the second imaging lens group is equal to the distance from the second beam detector to the second imaging lens group.

7. A calibration device for the measurement result of laser beam position stability, wherein, comprising: a light source, a laser beam position and pointing measurement device, and a sliding guide rail; by controlling the movement of the light source or the laser beam position and pointing measurement device arranged on the sliding guide rail, taking the movement amount as a first calibration parameter; taking the centroid change amount of the light source on the first beam detector of the beam position stability measurement device in the laser beam position and pointing measurement device during the movement process as a second calibration parameter; and obtaining calibration data for adjusting the measurement result of beam position stability according to the first calibration parameter and the second calibration parameter.

8. A calibration device for the measurement result of laser beam pointing stability, wherein, comprising: a light source, a sliding guide rail, a beam splitter, a focusing lens, a beam detector, and a laser beam position and pointing measurement device; the light emitting direction of the light source corresponds to the beam splitter and is arranged on the sliding guide rail; the beam splitter divides the light source into a first beam and a second beam; moving the light source so that the first beam enters the laser beam position and pointing measurement device along the transmission direction, passing through the beam pointing stability measurement device in the laser beam position and pointing measurement device, obtaining the first centroid change amount of the second beam detector in the beam pointing stability measurement device, and the second centroid change amount of the second beam reaching the beam detector after passing through the focusing lens along the transmission direction; and obtaining calibration data for adjusting the measurement result of beam pointing stability according to the first centroid change amount and the second centroid change amount.

9. The calibration device for the measurement result of laser beam pointing stability according to claim 8, wherein, further comprising: an attenuation sheet, the incident surface of the attenuation sheet faces the light emitting direction of the light source and is located between the beam splitter and the focusing lens.

10. A method for measuring the position and pointing of a laser beam, characterized in that, the measuring device in any one of claims 1-6 is used to measure the beam position stability and the beam pointing stability.

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