Brittle material through-type laser cutting processing technology has become a popular and widely used technique in the manufacturing industry. It is used in various fields, including cutting mobile phone glass cover plates, camera window protective cover plates, optical lenses and prisms, UTG ultra-thin glass, fingerprint recognition modules, LCD panels, automotive glass, and rearview mirrors. This technology is based on the nonlinear effect of ultrafast laser transmission in transparent media, which is used to form modification channels inside the material with a diameter of less than 3 micrometers in an extremely short time (~10ps). In this article, we will discuss the technical principle of through-type laser cutting processing technology and its applications.
Technical Principle
The brittle material through-type laser cutting processing technology is based on the nonlinear effect of ultrafast laser transmission in transparent media. When an ultrafast laser pulse (with a pulse width of tens of femtoseconds or hundreds of picoseconds) passes through a transparent material, such as glass, the material will absorb the laser energy and generate a local modification of the material. This local modification is a refractive index change caused by the electronic and thermal effects of the laser.
With the continuous absorption of the laser energy, the modification channels gradually extend along the laser propagation direction, forming a continuous modification channel inside the material. The modification channel’s diameter is less than 3 micrometers, which is much smaller than the laser spot size, allowing for a high precision cutting process.
The key to achieving high precision cutting is to accurately control the laser focus spot and the modification channel’s position. The Han’s through-type laser cutting system uses a unique small spot and long focal length deep light path design. The laser beam is first expanded to a larger diameter and then focused by a large-diameter focusing mirror, which can effectively reduce the laser energy density at the material surface and prevent the material from being damaged. At the same time, it can also improve the beam quality and stability.
In addition, the Han’s through-type laser cutting system uses a position synchronous output laser control design, which can accurately control the distance between the focusing spots. By synchronizing the laser output signal with the worktable’s position signal, the system can ensure that the laser is always focused on the same position on the material surface, regardless of the worktable’s position. This solves the problem of consistency in irregular cutting laser processing, and greatly improves the processing stability and accuracy.
Application Fields
Through-type laser cutting processing technology has a wide range of applications in various industries. Some of the significant application fields are as follows:
Cutting of Mobile Phone Glass Cover Plate
The through-type laser cutting process is widely used in cutting the glass cover plate for mobile phones. This technology produces high-precision cuts that are free from burrs, ensuring that the cover plate is smooth and scratch-free.
Cutting of Camera Window Protective Cover Plate
The camera window protective cover plate is a component in mobile phones and digital cameras that protects the camera lens. Through-type laser cutting processing technology can produce high-precision cuts in this material, ensuring that the protective cover plate fits accurately and provides maximum protection for the camera lens.
Cutting of Optical Lenses and Prisms
Through-type laser cutting processing technology is widely used in cutting optical lenses and prisms. This technology produces high-precision cuts that ensure that the optical components are of high quality and free from defects.
Cutting of UTG Ultra-thin Glass
UTG ultra-thin glass is used in various electronic devices, including smartphones and tablets. Through-type laser cutting processing technology can cut this material with high precision, ensuring that the glass is free from defects and burrs.