28 January 2010 Multiple range imaging camera operation with minimal performance impact
Author Affiliations +
Abstract
Time-of-flight range imaging cameras operate by illuminating a scene with amplitude modulated light and measuring the phase shift of the modulation envelope between the emitted and reflected light. Object distance can then be calculated from this phase measurement. This approach does not work in multiple camera environments as the measured phase is corrupted by the illumination from other cameras. To minimize inaccuracies in multiple camera environments, replacing the traditional cyclic modulation with pseudo-noise amplitude modulation has been previously demonstrated. However, this technique effectively reduced the modulation frequency, therefore decreasing the distance measurement precision (which has a proportional relationship with the modulation frequency). A new modulation scheme using maximum length pseudo-random sequences binary phase encoded onto the existing cyclic amplitude modulation, is presented. The effective modulation frequency therefore remains unchanged, providing range measurements with high precision. The effectiveness of the new modulation scheme was verified using a custom time-of-flight camera based on the PMD19-K2 range imaging sensor. The new pseudo-noise modulation has no significant performance decrease in a single camera environment. In a two camera environment, the precision is only reduced by the increased photon shot noise from the second illumination source.
© (2010) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Refael Z. Whyte, Refael Z. Whyte, Andrew D. Payne, Andrew D. Payne, Adrian A. Dorrington, Adrian A. Dorrington, Michael J. Cree, Michael J. Cree, } "Multiple range imaging camera operation with minimal performance impact", Proc. SPIE 7538, Image Processing: Machine Vision Applications III, 75380I (28 January 2010); doi: 10.1117/12.838271; https://doi.org/10.1117/12.838271
PROCEEDINGS
10 PAGES


SHARE
RELATED CONTENT


Back to Top