Light beam quality measuring device of ultraviolet excimer laser

Abstract

The invention relates to the technical field of excimer laser measurement, in particular to an ultraviolet excimer laser beam quality measuring device. The device comprises an excimer laser, a laser dispersion system which is arranged corresponding to a transmitting end of the excimer laser and divides a light path into two parts for transmission, a first measurement system which is matched with the laser dispersion system and is used for receiving a group of light paths, and a second measurement system which is arranged corresponding to the laser dispersion system and is used for receiving a second group of light paths. According to the technical scheme, two groups of light paths are arranged, pointing and position testing are separated, stray light in the light paths is avoided by using the wedge lens group, light is focused on the ultraviolet fluorescence conversion glass by using the first lens assembly and the second lens assembly, an ultraviolet light spot is changed into a light spot of a visible wave band, the light spot is imaged on a CCD (Charge Coupled Device) through the imaging lens of the camera, and the detection accuracy is improved. And finally carrying out data acquisition and processing on the light spots.

Description

Technical Field

[0001] The invention relates to the technical field of excimer laser measurement, and in particular to an ultraviolet excimer laser beam quality measurement device. Background Art

[0002] Excimer laser is a high-energy, short-wavelength gas laser widely used in precision machining, laser beam focusing, medical treatment, material surface treatment and other fields. The beam position and pointing measurement device of the excimer laser is used to ensure the accuracy and stability of its laser beam, especially in the case of extremely high precision requirements in these applications, monitoring and controlling the position, pointing and energy of the beam is very important.

[0003] Existing technology, CN202410942839.0, the existing excimer laser beam position, pointing, and energy measurement devices cannot meet the requirements of beam stability and high-precision simultaneous testing; and direct testing with ultraviolet instruments is relatively expensive.

[0004] Therefore, it is necessary to design a UV excimer laser beam quality measurement device to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a device for measuring the quality of an ultraviolet excimer laser beam to overcome the above-mentioned deficiencies in the prior art.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A device for measuring the quality of an ultraviolet excimer laser beam comprises an excimer laser, and is characterized in that it also comprises a laser dispersion system arranged corresponding to the emission end of the excimer laser and dividing the optical path into two for transmission, a first measurement system arranged in cooperation with the laser dispersion system for receiving a group of optical paths, and a second measurement system arranged corresponding to the laser dispersion system for receiving a second group of optical paths, wherein the laser dispersion system comprises a prism arranged at the emission end of the excimer laser, an optical wedge combination arranged in the refraction direction of the excimer laser after passing through the prism, a first lens group arranged at a group of refraction positions of the optical wedge combination, an attenuation plate arranged at a position after refraction of the first lens group and in front of the first measurement system, and a refraction component arranged at another group of refraction positions of the optical wedge combination and in front of the second measurement system.

[0008] Preferably, the optical wedge assembly includes a first wedge mirror and a second wedge mirror, and the first wedge mirror and the second wedge mirror rotate around a common axis.

[0009] Preferably, the first measuring system and the second measuring system are placed at different positions in the same horizontal space, and the refraction assembly includes a first reflector or a third wedge mirror arranged at another group of refraction positions of the optical wedge combination, a second reflector or a fourth wedge mirror arranged at the refraction position of the first reflector or the third wedge mirror, a third reflector or a fifth wedge mirror arranged at the refraction position of the second reflector or the fourth wedge mirror, and a second lens assembly placed in the refraction path of the light source of the first reflector or the third wedge mirror and the second reflector or the fourth wedge mirror.

[0010] Preferably, the first measurement system and the second measurement system have the same structure, both comprising an ultraviolet fluorescence conversion glass for preferentially receiving the light source, a camera imaging lens for receiving the light source converted by the ultraviolet fluorescence conversion glass, and a sensor or CCD camera for receiving the light source and collecting relevant data.

[0011] The beneficial effects of the present invention are as follows: the technical solution is configured into two groups of optical paths, the pointing and position tests are separated, a wedge mirror group is used to avoid stray light in the optical path, the first lens assembly and the second lens assembly are used to focus the light on the ultraviolet fluorescent conversion glass, the ultraviolet light spot is converted into a light spot in the visible band, the camera imaging lens is used to image the light spot on the CCD, and finally the light spot is subjected to data acquisition and processing. The equipment can be adjusted through the above-collected data, so that it can be used for dynamic adjustment and real-time calibration of the laser; and it can be used for large-scale measurement, suitable for the alignment and calibration of complex systems, with extremely high precision, and capable of detecting tiny displacements and offsets; the spatial position, intensity distribution and morphological information of the light beam can be obtained simultaneously, and intuitive light beam position and morphological analysis can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of an ultraviolet excimer laser beam quality measurement device of the present invention;

[0013] In the figure: 1-prism, 2-1-first wedge mirror, 2-2-second wedge mirror, 3-first lens group, 4-attenuation plate, 5-ultraviolet fluorescence conversion glass, 6-camera imaging lens, 7-sensor or camera, 8-1-first reflector or third wedge mirror, 8-2-second reflector or fourth wedge mirror, 8-3-third reflector or fourth-fifth wedge mirror, 9-second lens group. DETAILED DESCRIPTION

[0014] Reference Figure 1 , a device for measuring the quality of ultraviolet excimer laser beams, comprising an excimer laser 10, a laser dispersion system arranged corresponding to the emission end of the excimer laser and dividing the optical path into two for transmission, a first measurement system arranged in cooperation with the laser dispersion system for receiving a group of optical paths, and a second measurement system arranged corresponding to the laser dispersion system for receiving a second group of optical paths;

[0015] The laser dispersion system comprises a prism 1 disposed at the emission end of the excimer laser 10, an optical wedge combination disposed in the refraction direction of the excimer laser 10 after passing through the prism 1, a first lens group disposed at a group of refraction positions of the optical wedge combination, an attenuation plate 4 disposed at a position after the refraction of the first lens group and disposed in front of the first measurement system, and a refraction component disposed at another group of refraction positions of the optical wedge combination and disposed in front of the second measurement system;

[0016] The optical wedge assembly includes a first wedge mirror 2-1 and a second wedge mirror 2-2. The first wedge mirror 2-1 and the second wedge mirror 2-2 rotate around a common axis to generate different deflection angles to form a variable refractive power prism.

[0017] In order to facilitate the assembly and symmetry of the equipment and ensure the complete handling of the entire equipment, the first measurement system and the second measurement system are placed at different positions in the same horizontal space, so it is necessary to ensure the refraction and reception of another group of light sources, and the refraction assembly includes a first reflector or a third wedge mirror 8-1 set at the refraction position of another group of the optical wedge combination, a second reflector or a fourth wedge mirror 8-2 set at the refraction position of the first reflector or the third wedge mirror 8-1, a third reflector or a fifth wedge mirror 8-3 set at the refraction position of the second reflector or the fourth wedge mirror 8-3, and a second lens assembly 9 placed in the refraction path of the light sources of the first reflector or the third wedge mirror 8-1 and the second reflector or the fourth wedge mirror 8-2. Through multiple refractions of the first reflector or the third wedge mirror 8-1, the second reflector or the fourth wedge mirror 8-2, and the third reflector or the fifth wedge mirror 8-3, it is ensured that another group of light sources can be input exactly into the receiving position of the second measurement system;

[0018] The first lens assembly and the second lens assembly 9 are both for displaying a real image on the screen, so as to cooperate with receiving and collecting data and perform data collection and processing on the light spot.

[0019] The first measurement system and the second measurement system have the same structure, and both include an ultraviolet fluorescence conversion glass 5 for preferentially receiving the light source, a camera imaging lens 6 for receiving the light source after conversion by the ultraviolet fluorescence conversion glass, and a sensor or CCD camera 7 for receiving the light source and collecting relevant data; the light is focused on the ultraviolet fluorescence conversion glass, and the ultraviolet light spot is converted into a light spot in the visible band.

[0020] In order to facilitate the use with each sensor, the sensor or camera is externally connected to a control processing device, and the sensors or cameras are connected in communication. The sensor or camera 3 collects the spot image data corresponding to the spot reflected by the total reflector group at the corresponding collection position, and sends the spot image data to the control processing device. The control processing device adjusts the photosensitivity time of the image sensor collecting the spot image data according to the received spot image data, and calculates the laser beam quality parameters according to the spot image data that meets the preset conditions. The photosensitivity time of the sensor or camera spot image data refers to the real-time adjustment of the photosensitivity time of the sensor or camera collecting the spot image data during the process of the sensor or camera continuously collecting the spot image data, so as to accurately adjust the number of incident photons in the spot image, so as to achieve the sensor or camera working in the optimal linear dynamic range.

[0021] This implementation case, refer to Figure 1 After the equipment is arranged, the following parameters are calculated and obtained:

[0022] Lens group 1 focal length: 80mm, protection range: 50mm~300mm; Lens group 2 focal length: 400mm, protection range: 300mm~1000mm; Wedge lens group: wedge lens angle 10 degrees, protection range: 3 degrees~20 degrees Camera imaging lens focal length: 8mm, protection range: 5mm~20mm; 1 and 2-1 distance: 45mm, protection range: 20mm~100mm; 2-1 and 3 distance: 80mm, protection range: 50mm~150mm; 3 and 5 distance: 70mm, protection range: 30mm~140m m; distance between 2-2 and 8-1: 50mm, protection range: 50mm~150mm; distance between 8-1 and 9: 90mm, protection range: 40mm~200mm; distance between 9 and 8-2: 80mm, protection range: 30mm~200mm; distance between 8-2 and 8-3: 120mm, protection range: 70mm~240mm; distance between 8-3 and 5: 110mm, protection range: 50mm~220mm; this implementation case uses wavelengths of 193nm and 248nm, and the protection wavelength range is 190nm~1500nm.

[0023] This implementation case adopts the spectroscopic sampling method, using a beam splitter or a fiber optic splitter to separate part of the light beam, and indirectly monitors it through a secondary detector. This solution is non-invasive and suitable for scenarios where the integrity of the main optical path needs to be maintained. It is mainly used for laser output stability monitoring and optical power feedback control of fiber optic communication systems. The distance between each prism and wedge mirror is adjusted according to needs, so that it is suitable for different types of light beams.

[0024] The benefits of the present invention are that the technical solution is configured into two groups of optical paths to separate the pointing and position tests, and also uses a wedge mirror group to avoid stray light in the optical path, uses the first lens assembly and the second lens assembly to focus the light on the ultraviolet fluorescent conversion glass, uses the ultraviolet light spot to convert it into a light spot in the visible band, and images it on the CCD through the camera imaging lens, and finally collects and processes the light spot data. The equipment can be adjusted through the above collected data, so that it can be used for dynamic adjustment and real-time calibration of the laser; it can also be used for large-scale measurements, suitable for the alignment and calibration of complex systems, with extremely high accuracy, and can detect tiny displacements and offsets; it can simultaneously obtain the spatial position, intensity distribution and morphological information of the light beam, and can provide intuitive light beam position and morphological analysis, etc.

[0025] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An ultraviolet excimer laser beam quality measurement device, comprising an excimer laser, characterized in that: It also includes a laser dispersion system which is arranged corresponding to the emission end of the excimer laser and divides the optical path into two for transmission, a first measurement system which is arranged in conjunction with the laser dispersion system and is used to receive a group of optical paths, and a second measurement system which is arranged corresponding to the laser dispersion system and is used to receive a second group of optical paths. The laser dispersion system includes a prism placed at the emission end of the excimer laser, an optical wedge combination which is arranged in the refraction direction of the excimer laser after passing through the prism, a first lens group which is arranged at a group of refraction positions of the optical wedge combination, an attenuation plate which is arranged at a position after the refraction of the first lens group and is arranged in front of the first measurement system, and a refraction component which is arranged at another group of refraction positions of the optical wedge combination and is arranged in front of the second measurement system.

2. The ultraviolet excimer laser beam quality measurement device according to claim 1, characterized in that: The optical wedge assembly includes a first wedge mirror and a second wedge mirror, and the first wedge mirror and the second wedge mirror rotate around a common axis.

3. The ultraviolet excimer laser beam quality measurement device according to claim 1, characterized in that: The first measuring system and the second measuring system are placed at different positions in the same horizontal space, and the refraction assembly includes a first reflector or a third wedge mirror arranged at another group of refraction positions of the optical wedge combination, a second reflector or a fourth wedge mirror arranged at the refraction position of the first reflector or the third wedge mirror, a third reflector or a fifth wedge mirror arranged at the refraction position of the second reflector or the fourth wedge mirror, and a second lens assembly arranged in the refraction path of the light source of the first reflector or the third wedge mirror and the second reflector or the fourth wedge mirror.

4. The ultraviolet excimer laser beam quality measurement device according to claim 3, characterized in that: The first measurement system and the second measurement system have the same structure, and both include ultraviolet fluorescence conversion glass for preferentially receiving light source, a camera imaging lens for receiving light source converted by the ultraviolet fluorescence conversion glass, and a sensor or CCD camera for receiving light source and collecting relevant data.

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