Product Code: ICA12_M308

Advances in Ultra Short Pulsed Parallel Processing Using a Spatial Light Modulator - Invited Presentation - 40 Minutes
Authors:
Stuart P. Edwardson, Laser Engineering Group, Centre for Materials and Structures, School of Engineering, Univ. of Liverpool; Merseyside Great Britain
Zheng Kuang, Laser Engineering Group, Centre for Materials and Structures, School of Engineering, Univ. of Liverpool; Liverpool Great Britain
Dun Liu, Laser Engineering Group, Centre for Materials and Structures, School of Engineering, Univ. of Liverpool; Liverpool Great Britain
Walter Perrie, Laser Engineering Group, Centre for Materials and Structures, School of Engineering, Univ. of Liverpool; Liverpool Great Britain
Geoff Dearden, Laser Engineering Group, Centre for Materials and Structures, School of Engineering, Univ. of Liverpool; Liverpool Great Britain
Ken Watkins, Laser Engineering Group, Centre for Materials and Structures, School of Engineering, Univ. of Liverpool; Liverpool Great Britain
Presented at ICALEO 2012

Laser patterning is a key industrial process in a number of high precision manufacturing processes such as in organic light emitting diode (OLED) displays, solid-state lighting foils and solar cells. Ultrafast lasers are of particular interest for these applications as they may enable selective ablative removal of OLED layers with minimal energy density requirements on the target. Since sufficient laser output from commercial laser sources is currently exceeding single beam process requirements, parallel processing with multiple beams could provide a novel route for up-scaling processing speed and reduce manufacturing costs. Presented in this paper are the latest advances in the use of a reflective liquid crystal on silicon spatial light modulator, driven by fast computer-generated holograms, for splitting a parent laser beam into a number of beamlets and to digitally manipulate their position and laser intensity on the target. Demonstrated is high throughput precision patterning of silicon, titanium, thin film electrodes (ITO anode and metal cathode) on flexible and glass substrates and 3D refractive index laser inscription of clinical grade PMMA. The benefits and current limitations of the techniques are discussed in detail.