The paper presents a mathematical modeling of the transmission / modulation functions of the classical optical chopper wheels - with windows with linear edges. Based on our previous analytical analysis on constant intensity distributions (top-hat) laser beams, in the present paper the complete modeling and simulation of the chopping process of the light beam sections with Gaussian distributions is proposed. The different possible cases of the relationships between the geometry of the chopper blades and of the beam section in the plane of the wheel are considered. The three relevant situations that can be met are approached: (i) large blades in front of the beam section (that can be thus completely covered by each blade): (ii) narrow single blade in front of the (larger) beam section; (iii) multiple narrow blades placed simultaneously in front of the beam section. The experimental chopper module we have built with different chopper wheels that we have designed and fabricated as prototypes is also reviewed. Perspectives and future work on other types of optical chopper configurations conclude the study.

Date Published: 13 May 2013
PDF: 11 pages
Proc. SPIE 8789, Modeling Aspects in Optical Metrology IV, 87890E (13 May 2013); doi: 10.1117/12.2020383

Published in SPIE Proceedings Vol. 8789:
Modeling Aspects in Optical Metrology IV
Bernd Bodermann; Karsten Frenner; Richard M. Silver, Editor(s)