Self-imaging with curved gratings

OPTICS COMMUNICATIONS

卷:283

Article

Jose Torcal-Milla, Francisco¹ 

[1] Univ Complutense Madrid, Dept Opt, Appl Opt Complutense Grp, E-28040 Madrid, Spain

关键词: Diffraction gratings;    Talbot effect;    Self-imaging;    Curved gratings;   

DOI  :  10.1016/j.optcom.2010.06.008

来源: Elsevier

【 摘 要 】

We analyze the near field behavior of binary amplitude gratings which present a curved profile. This configuration has an important application in rotary optical encoders. This kind of encoders is used to measure the angular displacement between two different parts of the devices. To our knowledge, its behavior in the near field has not been analyzed yet. We have found that Talbot effect is produced but the period of the self-images and Talbot distances change as we separate from the grating. We have fabricated a curved grating and have performed the experiment to corroborate the behavior theoretically found. This fact could be useful in systems that use Talbot effect to measure displacements, since the mechanical tolerances grow. (C) 2010 Elsevier B.V. All rights reserved.

【 授权许可】

Free