Due to technical development of the adaptive optics, use of them in various laser processing applications has become possible. These techniques based on the adaptive optics have been applied with various lasers to generate diffraction patterns with equal intensity spots. In this paper ultrashort laser pulse ablation with intensity modulated diffraction pattern is presented. Diffraction patterns are generated with the Computer Generated Holograms (CGH) created using the Spatial Light Modulator (SLM). Applied CGHs are designed using method based on the Iterative Fourier Transform Algorithm (IFTA). Added to this Fresnel lenses are used to avoid problems with 0th-diffraction order. With this kind of designing procedure it is possible to generate diffraction patterns with intensity variation between diffracted spots. By intensity modulating the diffracted beams it is possible to ablate virtually arbitrary patterns with depth variation into the different materials. In this paper different kinds of CGHs are designed to generate various diffraction patterns with intensity modulation. These patterns are used to ablate greyscale images directly into the silicon using ultrashort pulses.
|Title of host publication||Proceedings of ICALEO 2013|
|Place of Publication||Orlando, Fla. USA|
|Publisher||Laser Institute of America|
|Publication status||Published - 2013|
|MoE publication type||Not Eligible|
|Event||32nd International Congress on Applications of Lasers & Electro-Optics, ICALEO - Miami, United States|
Duration: 6 Oct 2013 → 10 Oct 2013
Conference number: 32
|Conference||32nd International Congress on Applications of Lasers & Electro-Optics, ICALEO|
|Period||6/10/13 → 10/10/13|
- femtosecond laser
- spatial light modulator
- computer generated hologram
- laser marking
Kaakkunen, J., Silvennoinen, M., Päiväsaaari, K., Laakso, P., & Vahimaa, P. (2013). Parallel femtosecond laser processing using intensity modulated diffraction pattern produced with spatial light modulator. In Proceedings of ICALEO 2013 (pp. 672-676). Laser Institute of America.