Optical sensor positioning for eye-tracking with numerically efficient raytracing models

Digital Optical Technologies, pp. 27

Abstract

Sensor positions have a significant impact on the performance of optical sensing systems but often suffer from constraints due to partially blocked targets. In the scope of the EU and BMBF cofunded project “Vision Optics with Integrated VCSELs and Autofocal Lenses” (VIVA), VCSELs with integrated photodiodes (ViP) are placed in the frame of glasses to track the gaze direction of the wearer. Here, we present an optimization tool for positioning these sensors in the frame of the glasses considering constraints due to eyelashes and eyelids. To accurately map the solution space of possible sensor positions, all geometric constraints are simplified for numerically efficient raytracing. The sensor placement area is then discretized. For each position, rays are sent in the direction of the target in a grid and the quality of the position is evaluated by the number of rays hitting the target under a desired angle. The evaluation results are used to select an optimized combination of sensor positions. This allows the sensing system to evaluate the pose of the eye for a variety of gaze directions and glasses positions.

Authors 6

1. Tim Barcikowski Aachen

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen Univ. (Germany)

2. Oskar Hofmann Aachen

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen Univ. (Germany)

3. Carsten C. Reichert

   Robert Bosch (Germany)

   Affiliation as printed

   Robert Bosch GmbH (Germany)

4. Johannes Meyer

   Robert Bosch (Germany)

   Affiliation as printed

   Robert Bosch GmbH (Germany)

5. Annika Bonhoff
6. Carlo Holly Aachen Fraunhofer Institute for Laser Technology (ILT)

   Fraunhofer Institute for Laser Technology · RWTH Aachen University

   Affiliation as printed

   Fraunhofer Institute for Laser Technology (Germany)

   RWTH Aachen Univ. (Germany)