Sensor-Realistic Simulations for Evaluation and Planning of Optical Measurement Systems With an Application to Laser Triangulation

Abstract

Image acquisition plays a central role in optical measurement systems. To configure machine vision setups, engineers often go through some empirical best practices to evaluate the measurement in different geometrical and optical configurations. This approach turns out to be expensive, tedious, and sometimes even unsuitable for nontrivial tasks. To automate this process, realistic synthetic images allow us to evaluate and optimize imaging setups without employing physical parts and sensors. Available computer graphics rendering techniques can be very beneficial for realistic simulation of images in machine vision systems. Simulating optical measurement systems, however, requires taking extra simulation components into account, including the wave optics effects and realistic spectral response and stochastic noise of the digital sensor. In this article, we focus on physical simulation of optical measurement systems and further propose and verify a sensor-realistic simulation framework for this purpose. We demonstrate the results in different steps for a laser triangulation measurement system, and verify them against experimental images, both qualitatively and quantitatively. The measurement with a laser light source results in wave optics effects which cannot be modeled by conventional ray-tracing methods. The concepts of this article are, however, general to many optical systems with both coherent and/or incoherent light sources. The agreement of simulations with reality is a promising proof of concept for machine vision experts, to move towards automating the setup planning process by means of sensorrealistic simulations.

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