Abstract

A color-coded lens system is designed and built for three-dimensional (3D) particle location. As it has wavelength-dependent focal length, it can obtain a series of multifocus images in a single snapshot by separating the red, green, and blue channels of the image captured by a color camera. A light source consisting of red, green, and blue LEDs is customized to provide narrowband illumination. In this way, the depth of field can be extended. A three-pinhole aperture is introduced into the system to produce defocus-based triangular patterns that help to encode the particle depth. The accurate 3D particle position can finally be obtained by fusing the information from the three color channels. Experimental results demonstrate that the system is well suited for applications where particles may be irregular or extended depth of field is needed.

© 2019 Optical Society of America

Wavelet-based depth-of-field extension, accurate autofocusing, and particle pairing for digital inline particle holography

Wu Yingchun, Wu Xuecheng, Yang Jing, Wang Zhihua, Gao Xiang, Zhou Binwu, Chen Linghong, Qiu Kunzan, Gérard Gréhan, and Cen Kefa
Appl. Opt. 53(4) 556-564 (2014)

Three-dimensional optical metrology with color-coded extended depth of focus

E. Hasman, S. Keren, N. Davidson, and A. A. Friesem
Opt. Lett. 24(7) 439-441 (1999)

Passive depth estimation using chromatic aberration and a depth from defocus approach

Pauline Trouvé, Frédéric Champagnat, Guy Le Besnerais, Jacques Sabater, Thierry Avignon, and Jérôme Idier
Appl. Opt. 52(29) 7152-7164 (2013)

Three dimensional multi-molecule tracking in thick samples with extended depth-of-field

Heng Li, Danni Chen, Gaixia Xu, Bin Yu, and Hanben Niu
Opt. Express 23(2) 787-794 (2015)

High-speed color three-dimensional measurement based on parallel confocal detection with a focus tunable lens

Chang-Soo Kim, Wooseop Kim, Kyuhang Lee, and Hongki Yoo
Opt. Express 27(20) 28466-28479 (2019)