RT Journal Article
T1 Collimation technique and testing applied to finite size polychromatic sources
A1 Torcal Milla, Francisco José
A1 Sánchez Brea, Luis Miguel
AB Highly collimated beams are required in numerous applications and techniques. Different methods have been proposed for collimating monochromatic point light sources during the recent years. In this work, we analyze how a finite size and polychromatic light source can be collimated using only one diffraction grating and a CMOS camera placed after the source and the collimating lens. For this, we determine the period of the fringes diffracted by the grating and compare it with the period of the grating. Analytical equations are obtained to predict the amplitude of the fringes and their period. Since self-images disappear for finite size polychromatic sources at long distances from the grating, the period has to be measured close to the grating. In addition, we give an analytical equation to determine the error in the positioning of the source in terms of the source size and the setup parameters. Finally, we experimentally corroborate the obtained analytical formalism using a white LED of size s = 0.6 mm collimated by a lens with focal length f = 25 mm, and a Ronchi binary grating of period d = 250 mu m. In this case, we achieve an experimental error in the positioning of the source with respect to the focal plane of the lens of delta z(exp) = 92 mu m.
PB Optical Soc Amer
SN 1559-128X
YR 2017
FD 2017-04-20
LK https://hdl.handle.net/20.500.14352/17870
UL https://hdl.handle.net/20.500.14352/17870
LA eng
NO 2017 Optical Society of America.This work was started while Francisco José Torcal-Milla was contracted by the Universidad Complutense de Madrid. This work has been supported by project SPIP2015-01812 “Dispositivo LiFi de comunicación de datos sensibles de vehículos para incremento de la seguridad vial” of the Ministerio de Interior of Spain.
NO Direccion General de Trafico, Ministerio del Interior of Spain
DS Docta Complutense
RD 7 abr 2025