- Volume 19 Issue 6
We present a simple method to determine the focal distances of lenses with the Talbot self-images. This method uses only one grating, and a priori knowledge of the period of the grating is replaced with a linear relation between the (de)magnified periods of the Talbot images and the lens-to-grating distance. A thick lens whose effective focal length is 500 mm was used to validate the method, and the focal distance of the converging beam was determined with the difference of 0.15% for the nominal focal distance of 521.9 mm. The determined period of the grating with the difference of 0.2% also supports the validation.
Focal distances;Talbot self-imaging;Gratings
- L. Liao, F. C. B. de Albuquerque, R. E. Parks, and J. M. Sasian, “Precision focal-length measurement using imaging conjugates,” Opt. Eng. 51, 113604 (2012). https://doi.org/10.1117/1.OE.51.11.113604
- Y. Mejia, “Improvement in the measurement of focal length using spot patterns and spherical aberration,” Appl. Opt. 52, 5577-5584 (2013). https://doi.org/10.1364/AO.52.005577
- E. O’Donnell, Product Technician, Edmund Optics, Personal Communication (2015).
- S. Lee, “Talbot interferometry for measuring the focal length of a lens without Moiré fringes,” J. Opt. Soc. Korea 19, 165-168 (2015). https://doi.org/10.3807/JOSK.2015.19.2.165
- L. M. Sanchez-Brea, F. J. Torcal-Milla, F. J. Salgado-Remacha, T. Morlanes, I. Jimenez-Castillo, and E. Bernabeu, “Collimation method using a double grating system,” Appl. Opt. 49, 3363-3368 (2010). https://doi.org/10.1364/AO.49.003363
- L. M. Sanchez-Brea, F. J. Torcal-Milla, J. M. Herrera-Fernandez, T. Morlanes, and E. Bernabeu, “Self-imaging technique for beam collimation,” Opt. Lett. 39, 5764-5767 (2014). https://doi.org/10.1364/OL.39.005764
- M. de Angelis, S. De Nicola, P. Ferraro, A. Finizio, and G. Pierattini, “Analysis of Moiré fringes for measuring the focal length of lenses,” Optics and Lasers in Eng. 30, 279-286 (1998). https://doi.org/10.1016/S0143-8166(98)00026-8
- X. Jin, J. Zhang, J. Bai, C. Hou, and X. Hou, “Calibration method for high-accuracy measurement of long focal length with Talbot interferometry,” Appl. Opt. 51, 2407-2413 (2012). https://doi.org/10.1364/AO.51.002407
- Y. Nakano and K. Murata, “Talbot interferometry for measuring the focal length of a lens,” Appl. Opt. 24, 3162-3166 (1985). https://doi.org/10.1364/AO.24.003162
- B. DeBoo and J. Sasian, “Precise focal-length measurement technique with a reflective Fresnel-zone hologram,” Appl. Opt. 42, 3903-3909 (2003). https://doi.org/10.1364/AO.42.003903