Collimation method using a double grating system



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Sánchez Brea, Luis Miguel and Torcal Milla, Francisco José and Salgado Remacha, Francisco Javier and Morlanes Calvo, Tomás and Jiménez Castillo, Isidoro and Bernabeu Martínez, Eusebio (2010) Collimation method using a double grating system. Applied Optics, 49 (17). pp. 3363-3368. ISSN 1559-128X

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We present a collimation technique based on a double grating system to locate with high accuracy an emitter in the focal plane of a lens. Talbot self-images are projected onto the second grating producing moiré interferences. By means of two photodetectors positioned just behind the second grating, it is possible to determine the optimal position of the light source for collimation by measuring the phase shift between the signals over the two photodetectors. We obtain mathematical expressions of the signal in terms of defocus. This allows us to perform an automated technique for collimation. In addition, a simple and accurate visual criterion for collimating a light source using a lens is proposed. Experimental results that corroborate the proposed technique are also presented.

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© 2010 Optical Society of America.
This research has been supported by project CCG08-UCM/DPI-3952 of Dirección General de Universidades e Investigación de la Consejería de Educación de la Comunidad de Madrid and by project DPI2008-02391 of the Ministerio de Ciencia e Innovación of Spain.

Uncontrolled Keywords:Shearing Interferometer, Lau, Diffraction, Illumination, Aberration
Subjects:Sciences > Physics > Optics
ID Code:26188
Deposited On:17 Jul 2014 11:45
Last Modified:17 Jul 2014 11:45

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