Optimizing Laser Glass Cutting with Diffractive Beam Shaping

Laser glass cutting with ultra-short IR pulses is lately growing to become a key technique for the high throughput glass processing. Cutting thick glasses (>500um) using this technique possess unique challenges, as the laser energy needs to be both focused to a tight spot, and spread evenly in the glass depth. We offer several solutions to help our customers with their glass cutting needs. For customers interested in a complete solution and optimal performance, we have recently launched the DeepCleave Module. Other, component level Elongated Focus and Multifocal DOEs elements. These elements increase the focal depth of the beam, or split the focal region into several spots, enabling improved glass cutting performance. These components can be used with both single and multi-mode lasers with flexible input beam diameter and generally require external focusing optics.

Using these components, best glass cutting results are often achieved by using our Multifocal module, which boasts a 0.45NA and a clear aperture of 20mm, making it a perfect fit for our Beam Foci elements.

Our DeepCleave module focuses an incident single mode laser into a tight spot with ~ 1.8 um waist size along the entire Depth of Focus range (1-2mm typical range) . The focused spot is equivalent to 0.35 objective NA and is ideally suited for glass cutting of thick glasses, such as flat panels. This module is a complete optical solution for cutting applications. No need for additional high NA objectives or other high cost optics. The DeepCleave module differs from standard EF elements by constant peak power along the focus region and requires low M^2 and accurate input beam size.

Functional properties include:
• Depth of Focus typical range (can be customized): 1-2mm
• Spot size (along entire depth of focus): < 2um
• Z-axis Flat-top with constant peak power along DOF
• Complete optical solution with no need for additional high NA objectives
• Module dimensions: dia. 30.5mm x length 106mm

The module is designed for the IR wavelength range, but can be customized to any desired wavelength and has shown success in microscopy applications as well, with 532nm wavelength. For more information on the products, please click here.