Application of a liquid crystal spatial light modulator to laser marking

Area of Science:

• Materials Science
• Laser Physics
• Surface Engineering

Background:

• Traditional laser marking often uses low-power lasers, limiting pattern complexity and scale.
• Existing methods struggle with speckle intensity distribution and thermal effects, impacting mark quality.

Purpose of the Study:

• To demonstrate laser marking using nanosecond (ns) pulse duration lasers with a liquid crystal spatial light modulator (SLM).
• To enable the generation of complex, large-scale 2D patterns on metal surfaces.
• To improve mark quality by mitigating speckle and thermal effects.

Main Methods:

• Utilized a nanosecond pulse duration laser system.
• Employed a liquid crystal spatial light modulator (SLM) for dynamic pattern generation.
• Applied the technique to thin films and bulk metal surfaces.

Main Results:

• Successfully generated 2D patterns directly onto metal surfaces using ns lasers and SLM.
• Demonstrated the capability for more complex and larger-scale marks compared to previous low-power laser demonstrations.
• Showcased improved mark quality through dynamic control, reducing speckle and thermal impact.

Conclusions:

• Nanosecond laser marking with SLMs offers a versatile and scalable solution for direct pattern generation on metals.
• The dynamic control capabilities of SLMs significantly enhance the quality and applicability of laser marking.
• This approach integrates well with industrially proven laser systems for practical applications.