The present invention relates to steered laser beam systems, and more particularly to a system and method for efficient laser processing of a moving web-based material.
Laser systems typically use high-power laser beams for cutting, slitting, scoring, marking and other related laser processing of web-based materials. In many applications, a fixed laser beam is focused through a lens to cause local vaporization or degradation of the material as the material is moved relative to the focused laser beam.
For example, slits may be produced in a moving web-based material, such as a plastic film, using a CO2 laser beam. A roll handler moves the plastic film under the focused laser beam in a linear direction, and an encoder monitors the speed of the material.
Unfortunately, many plastic films absorb only a fraction of the laser energy at CO2 wavelengths and thus require significant laser power to create a slit in the material. As a result, there is an ideal power density/speed relationship for a given material of a given thickness. When the plastic film moves at slower speeds, a less powerful CO2 laser is required to produce slits in the film because the laser is given a longer duration of time to produce each slit. However, when the plastic film moves at higher speeds, a more powerful CO2 laser is required because the laser is given a shorter duration of time to produce each slit.
Therefore, there is a need in the art for a system and method for increasing the processing speed of the moving web-based material without increasing the required power density of the laser. Or similarly, there is a need in the art for a system and method for reducing the power density of the laser without sacrificing the processing speed of the moving web-based material.