Optical Quality Control of Windshields for ADAS Applications

LaVisions Glass-SFR inspex system provides comprehensive measurements of optical glass quality for safe autonomous driving with ADAS camera systems. Optical transmission parameters like contrast reduction or optical power (diopter) at the ADAS camera area of the windshield are carried out by image quality evaluation of the innovative analysis technique.

With the Glass-SFR inspex system the impact of the windshield to the image quality of the ADAS camera systems under investigation are determined for realistic object distances: Very precise comparison measurements of the Spatial Frequency Response (SFR) / Modulation Transfer Function (MTF) are received by the image analysis of objects´ edge contrasts following the ISO12233.

Additionally the Glass-SFR inspex is capable of a precise 2D diopter analysis of the ADAS camera area at the windshield with high spatial resolution in the milli-diopter range for horizontal and vertical directions. The inspected windshield is placed in front of the high-resolution camera-based system recording images of a calibration pattern displayed on a monitor behind the windshield. The measured displacement field of the pattern through the windshield yields directly the diopter map. The field of view is freely selectable changing the system position and can cover also smaller segments like the ADAS viewport. Fully automated diopter measurements are carried out on car glass test benches as well as inspecting already installed windscreens from inside of the car.