Optical element cleaning apparatus and method

Abstract

The application discloses an optical element cleaning device, which comprises a laser confining unit and an electrostatic adsorption unit, and the laser confining unit comprises a laser system and a beam shaping system. The application provides an optical element cleaning method, wherein the laser beam emitted by the laser system is shaped into a Gaussian beam by the beam shaping system, so that the electric field generated by the electrostatic adsorption unit covers the Gaussian light field; the starting time of the laser confining unit and the electrostatic adsorption unit is controlled to be synchronous with the light transmission time of the optical element, so that the flight path of the damage spatter ions passes through the Gaussian light field and the electric field generated by the electrostatic adsorption unit; the Gaussian light field is used to control the movement of the particles to the electrostatic adsorption unit, and the particles are adsorbed by the electrostatic adsorption unit. The application uses the confining force of the Gaussian light field to limit the spatter ions in the Gaussian light field, controls the movement of the particles to the electrostatic adsorption unit by adjusting the energy of the Gaussian light field, and adsorbs the particles by the electrostatic adsorption unit, so that the purpose of removing the damage particles is achieved.

Description

Technical Field

[0001] This invention relates to the field of optical component maintenance technology, and in particular to an optical component cleaning device and method. Background Technology

[0002] Large-aperture optical components play a crucial role in many high-end technology fields due to their high precision and large size. High-energy and high-power laser devices contain a large number of large-aperture optical components, bearing the ultimate output of high energy and high power. Among the damage to optical components, particulate contaminants are a significant contributing factor. These contaminants may originate from the manufacturing process of the optical components or from the use of the optical components in high-power laser systems, leading to the adhesion of contaminants such as metal particles to the component surface. Particulate contaminants alter the light field intensity distribution, causing the light field energy to be absorbed by the particles. Upon absorbing laser light, the particles instantly heat up, potentially leading to an explosion that generates high temperature and pressure, causing thermal ablation and other damage to the component surface.

[0003] Therefore, how to change the current situation in the technology where particulate contaminants cause damage to optical components, thus affecting the operation of high-energy and high-power laser devices, has become an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide an optical component cleaning device and method to solve the problems existing in the prior art, to remove damaged particles from optical components online, with high processing efficiency, which is beneficial to improving the operational stability of high-energy and high-power laser devices.

[0005] To achieve the above objectives, the present invention provides the following solution:

[0006] This invention provides a cleaning device for optical components, comprising:

[0007] A laser confinement unit includes a laser system and a beam shaping system. The laser system emits a laser beam, and the laser beam shaping system shapes the laser beam emitted by the laser system into a Gaussian beam. The beam emitted by the laser beam shaping system is located on the light-emitting side of the optical element and is parallel to the light-emitting surface of the optical element.

[0008] An electrostatic adsorption unit is disposed on the light-emitting side of the optical element and along the beam emission direction of the laser confinement unit. The electrostatic adsorption unit is located behind the optical element and is capable of adsorbing damaged particles on the surface of the optical element.

[0009] Preferably, the laser system uses an Nd:YAG laser with an output energy of 300mJ, a wavelength of 1064nm, a pulse width of 10ns, and a frequency of 1-10Hz.

[0010] Preferably, the beam shaping system includes a first lens and a second lens arranged sequentially along the laser beam emission direction. The first lens is positioned close to the laser system. The diameter of the first lens is 20 mm, and the diameter of the second lens is 50 mm. The first lens and the second lens are used to shape and expand the laser beam emitted by the laser system.

[0011] Preferably, the electrostatic adsorption unit includes an electrode and an electret film disposed on the electrode. The electrode can be connected to an external power source to generate electrostatic adsorption force on the electret film. The electret film is located on the side of the electrode closer to the laser confinement unit.

[0012] Preferably, the static voltage of the electrode is 300V.

[0013] Preferably, the angle between the beam emission direction of the electrostatic adsorption unit and the laser confinement unit is 30°.

[0014] Preferably, the optical element cleaning device further includes a control unit, and the laser confinement unit and the electrostatic adsorption unit are both communicatively connected to the control unit.

[0015] The present invention also provides a method for cleaning optical components, utilizing the above-described optical component cleaning apparatus, comprising the following steps:

[0016] Step 1: The laser system emits a laser beam parallel to the light-emitting surface of the optical element. The laser beam emitted by the laser system is shaped into a Gaussian beam by the beam shaping system to form a Gaussian light field, so that the electric field generated by the electrostatic adsorption unit covers the Gaussian light field.

[0017] Step 2: Control the start-up time of the laser confinement unit and the electrostatic adsorption unit to synchronize with the light transmission time of the optical element, so that the flight path of the damaged sputtered ions passes through the Gaussian light field and the electric field generated by the electrostatic adsorption unit. Use the Gaussian light field to control the particles to move towards the electrostatic adsorption unit, and the particles are adsorbed by the electrostatic adsorption unit to remove the damaged particles.

[0018] The present invention achieves the following technical advantages over the prior art: The optical element cleaning device of the present invention includes a laser confinement unit and an electrostatic adsorption unit. The laser confinement unit includes a laser system and a beam shaping system. The laser system can emit a laser beam, and the laser beam shaping system is used to shape the laser beam emitted by the laser system into a Gaussian beam. The beam emitted by the laser beam shaping system is located on the light-emitting side of the optical element and is parallel to the light-emitting surface of the optical element. The electrostatic adsorption unit is disposed on the light-emitting side of the optical element and along the beam emission direction of the laser confinement unit. The electrostatic adsorption unit is located behind the optical element and can adsorb damaged particles on the surface of the optical element.

[0019] Meanwhile, the present invention also provides a method for cleaning optical components. Using the aforementioned optical component cleaning device, a laser system emits a laser beam parallel to the light-emitting surface of the optical component. A beam shaping system shapes the laser beam emitted by the laser system into a Gaussian beam to form a Gaussian light field, so that the electric field generated by the electrostatic adsorption unit covers the Gaussian light field. The start-up time of the laser confinement unit and the electrostatic adsorption unit is controlled to be synchronized with the light transmission time of the optical component, so that the flight path of the damaged sputtered ions passes through the Gaussian light field and the electric field generated by the electrostatic adsorption unit. The Gaussian light field is used to control the particles to move towards the electrostatic adsorption unit, and the particles are adsorbed by the electrostatic adsorption unit to remove the damaged particles.

[0020] This invention utilizes the confinement force of a Gaussian light field on sputtered ions, restricting them within the field. By adjusting the energy of the Gaussian light field, the particles are controlled to move towards an electrostatic adsorption unit, which then adsorbs them, thus removing the damaged particles. This invention achieves online removal of damaged particles from optical components with high efficiency, employing a non-contact, non-destructive treatment method that generates no secondary pollution. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the optical element cleaning device disclosed in an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the Gaussian uniform light field of the optical element cleaning device disclosed in the embodiments of the present invention;

[0024] Figure 3This is a schematic diagram of the electrostatic system unit of the optical element cleaning device disclosed in the embodiments of the present invention;

[0025] Figure 4 This is a schematic diagram of the beam shaping system of the optical element cleaning device disclosed in the embodiments of the present invention.

[0026] In the figure: 1. Gaussian uniform light field; 2. Electrostatic adsorption unit; 3. Beam shaping system; 4. Laser system; 5. Control unit; 6. Electret film; 7. Electrode; 8. First lens; 9. Second lens. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] The purpose of this invention is to provide an optical component cleaning device and method to solve the problems existing in the prior art, to remove damaged particles from optical components online, with high processing efficiency, which is beneficial to improving the operational stability of high-energy and high-power laser devices.

[0029] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] This invention provides a cleaning device for optical components, including a laser confinement unit and an electrostatic adsorption unit 2. The laser confinement unit includes a laser system 4 and a beam shaping system 3. The laser system 4 can emit a laser beam, and the laser beam shaping system 3 is used to shape the laser beam emitted by the laser system 4 into a Gaussian beam. The beam emitted by the laser beam shaping system 3 is located on the light-emitting side of the optical component and is parallel to the light-emitting surface of the optical component. The electrostatic adsorption unit 2 is disposed on the light-emitting side of the optical component and along the beam emission direction of the laser confinement unit. The electrostatic adsorption unit 2 is located behind the optical component and can adsorb damaged particles on the surface of the optical component.

[0031] This invention utilizes the confinement force of a Gaussian light field on sputtered ions, restricting them within the field. By adjusting the energy of the Gaussian light field, the particles are controlled to move towards the electrostatic adsorption unit 2, which then adsorbs them, thus removing the damaged particles. This invention achieves online removal of damaged particles from optical components with high efficiency, employing a non-contact, non-destructive treatment method that generates no secondary pollution.

[0032] In this specific embodiment, the laser system 4 employs a Nd:YAG laser with an output energy of 300 mJ, a wavelength of 1064 nm, a pulse width of 10 ns, and a frequency adjustable from 1 to 10 Hz. The operating parameters of the laser system 4 can be adjusted according to the actual particle removal requirements.

[0033] Specifically, the beam shaping system 3 includes a first lens 8 and a second lens 9 arranged sequentially along the laser beam emission direction. The first lens 8 is positioned close to the laser system 4, and its diameter is 20 mm. The second lens 9 has a diameter of 50 mm. The first lens 8 and the second lens 9 are used to shape and expand the laser beam emitted from the laser system 4, forming a Gaussian uniform light field 1 parallel to the light-emitting surface of the optical element. In other embodiments of the present invention, the beam shaping system 3 includes a support frame and a shaping lens group movably mounted on the support frame. The shaping lens group is detachably connected to the support frame, and the specifications of the shaping lens group and the distance between the shaping lens group and the laser system 4 can be adjusted according to the beam shaping requirements. The support frame improves the working stability of the shaping lens group, further enhancing the flexibility, adaptability, and reliability of the beam shaping system 3.

[0034] More specifically, the electrostatic adsorption unit 2 includes an electrode 7 and an electret film 6 disposed on the electrode 7. The electrode 7 can be connected to an external power source to generate an electrostatic adsorption force in the electret film 6. The electret film 6 is located on the side of the electrode 7 close to the laser confinement unit to form a uniform electric field covering the Gaussian light field.

[0035] In this specific embodiment, the static voltage of electrode 7 is 300V. In practical applications, it can be adjusted according to the actual working conditions to ensure that the electrostatic adsorption unit 2 can adsorb damaged particles and improve the working reliability of the device.

[0036] It should also be emphasized that the angle between the beam emission direction of the electrostatic adsorption unit 2 and the laser confinement unit is 30°. In this specific embodiment, the angle between the electret film 6 and the transmission direction of the Gaussian uniform light field 1 is 30°, ensuring that the electric field formed by the electrostatic adsorption unit 2 can cover the Gaussian light field to adsorb damaged particles. In practical applications, the setting angle and position of the electret film 6 can be adjusted according to specific working conditions to meet adsorption requirements and improve the flexibility and adaptability of the device.

[0037] The optical element cleaning treatment device of the present invention further includes a control unit 5, a laser confinement unit and an electrostatic adsorption unit 2, all of which are communicatively connected to the control unit 5. The control unit 5 controls the laser confinement unit and the electrostatic adsorption unit 2, thereby improving the controllability of the device and the ease of operation of the device.

[0038] The present invention also provides a method for cleaning optical components, which utilizes the above-mentioned optical component cleaning apparatus and specifically includes the following steps:

[0039] A. The beam shaping system 3 is used to shape the single-pulse laser beam output from the laser system 4 into a Gaussian uniform light field 1, which is parallel to the light-emitting surface of the optical element.

[0040] B. Place the electret film 6 and the electrode 7 on the other side of the optical element, at a 30° angle to the transmission direction of the Gaussian uniform light field 1, so that the uniform electric field formed covers the Gaussian light field.

[0041] C. The start-up time of the laser system 4 and the electrode 7 is synchronized with the light transmission time of the optical element by the control unit 5, so as to ensure that the flight path of the damage sputtering particles passes through the Gaussian uniform light field 1 and the electric field.

[0042] D. Adjust the output energy of the laser system 4 and the voltage of the electrode 7 to improve the online removal efficiency of damaged particles;

[0043] E. Repeat steps C and D to complete the online removal of optical surface damage particles under different laser energies.

[0044] The optical element cleaning device and method of the present invention utilizes a laser system 4 to form a uniform Gaussian light field in the damaged and sputtered area of ​​the optical element. The Gaussian light field confines the sputtered particles within it. By adjusting the energy of the Gaussian light field, the particles are controlled to move towards an electrostatic adsorber and finally adsorb onto the surface of an electret film 6, thus achieving the purpose of removing damaged particles. This invention employs a non-contact, non-destructive processing method, has no environmental space requirements, provides excellent processing results (removal rate of micron-sized particles exceeding 90%), generates no secondary pollution, facilitates online processing, and has high processing efficiency.

[0045] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A cleaning device for optical components, characterized in that, include: A laser confinement unit includes a laser system and a beam shaping system. The laser system emits a laser beam, and the beam shaping system shapes the laser beam emitted by the laser system into a Gaussian beam. The beam emitted by the beam shaping system is located on the light-emitting side of the optical element and is parallel to the light-emitting surface of the optical element. An electrostatic adsorption unit is disposed on the light-emitting side of the optical element and along the beam emission direction of the laser confinement unit. The electrostatic adsorption unit is located behind the optical element and can adsorb damaged particles on the surface of the optical element. The electrostatic adsorption unit includes an electrode and an electret film disposed on the electrode. The electrode can be connected to an external power source to generate electrostatic adsorption force on the electret film. The electret film is located on the side of the electrode closer to the laser confinement unit. By adjusting the energy of the Gaussian light field, the particles are controlled to move towards the electrostatic adsorption unit, and the electrostatic adsorption unit adsorbs the particles.

2. The optical element cleaning treatment apparatus according to claim 1, characterized in that: The laser system uses an Nd:YAG laser with an output energy of 300mJ, a wavelength of 1064nm, a pulse width of 10ns, and a frequency of 1~10Hz.

3. The optical element cleaning treatment apparatus according to claim 1, characterized in that: The beam shaping system includes a first lens and a second lens arranged sequentially along the laser beam emission direction. The first lens is positioned close to the laser system. The diameter of the first lens is 20 mm, and the diameter of the second lens is 50 mm. The first lens and the second lens are used to shape and expand the laser beam emitted by the laser system.

4. The optical element cleaning treatment apparatus according to claim 1, characterized in that: The static voltage of the electrode is 300V.

5. The optical element cleaning treatment apparatus according to any one of claims 1-4, characterized in that: The angle between the beam emission direction of the electrostatic adsorption unit and the laser confinement unit is 30°.

6. The optical element cleaning treatment apparatus according to any one of claims 1-4, characterized in that: It also includes a control unit, and the laser confinement unit and the electrostatic adsorption unit are both communicatively connected to the control unit.

7. A method for cleaning optical components, characterized in that, The optical element cleaning apparatus according to any one of claims 1-6 comprises the following steps: Step 1: The laser system emits a laser beam parallel to the light-emitting surface of the optical element. The laser beam emitted by the laser system is shaped into a Gaussian beam by the beam shaping system to form a Gaussian light field, so that the electric field generated by the electrostatic adsorption unit covers the Gaussian light field. Step 2: Control the start-up time of the laser confinement unit and the electrostatic adsorption unit to synchronize with the light transmission time of the optical element, so that the flight path of the damaged sputtered ions passes through the Gaussian light field and the electric field generated by the electrostatic adsorption unit. Use the Gaussian light field to control the particles to move towards the electrostatic adsorption unit, and the particles are adsorbed by the electrostatic adsorption unit to remove the damaged particles.

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