For stereoscopic systems designed for metrology applications, the accuracy of camera calibration dictates the precision of the 3D reconstruction. In this paper, the impact of various calibration conditions on the reconstruction quality is studied using a virtual camera calibration technique and the design file of a commercially available lens. This technique enables the study of the statistical behavior of the reconstruction task in selected calibration conditions. The data show that the mean reprojection error should not always be used to evaluate the performance of the calibration process and that a low quality of feature detection does not always lead to a high mean reconstruction error.

Camera calibration is essential for any optical system used to obtain 3D measurements from images. The precision of the 3D depth estimation relies on an appropriate camera model and the accurate estimation of model parameters. These parameters are sensitive to environmental conditions and it is well established that a vision system should be calibrated in operating conditions. This is not always possible since the calibration process is often tedious and time-consuming. Unfortunately, the use of poorly estimated calibration parameters for 3D reconstruction and measurements may lead to suboptimal performance of the system and inaccurate depth estimation. This paper presents a technique using an existing camera model and optical design software to perform calibration simulations. This virtual calibration technique allows for a study of the impact of environmental conditions on the calibration parameters. Using this procedure, it is also possible to predict the statistical behavior of the calibration parameters considering the chosen fabrication processes and tolerances. It can assist vision scientists in the choice of the optical system that best meets the requested precision of the 3D reconstruction. This technique could eventually be integrated in the lens design process to create more reliable optical systems that could be calibrated and used in a range of environmental conditions with a very small variation of their calibration parameters.

Worldwide, volunteers from student associations and non-profit organizations carry out outreach activities with high school students in their classrooms. Most of the time, these activities highlight optical phenomena but do not provide information about the reality of researchers in companies and universities. To address this issue, Université Laval's OSA and SPIE student chapters set up a demonstration laboratory dedicated to outreach, located in a research center. In this paper, we list the advantages of this type of facility as well as the steps leading to the creation of the laboratory, and we give an overview of the demonstration laboratory.

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It often takes one single event to interest teenagers in a topic that will become a passion or a career. It is in this spirit that the SPIE and OSA Student Chapters at Université Laval created the Photonic Games three years ago, to kindle an interest in teenagers towards studies and careers in optics. The activity, offered each year to more than a hundred grade 11 students, is divided in two parts. First, we offer a hands-on workshop in their classrooms about reflection, refraction, dispersion, birefringence and polarization. A few days later, all the students come to the Centre d'optique, photonique et laser (COPL) at Université Laval for a day of competition where a volunteer physics student accompanies each team of four students. Challenges are various to promote the qualities that make great scientists: creativity, teamwork, knowledge, inquisitiveness, self-confidence and perseverance. The first two editions of the Photonic Games have proven to be beneficial for the students, teachers and volunteers, and we endeavor to improve it as we construct on our experience with the past editions to fine-tune and improve the Photonic Games concept.