® autocalibration tools can handle the challenges of wide-view visual systems for flight simulation that use collimated light.

Magdeburg / Berlin (Germany), May 13th, 2019:
Such systems are used to handle specific requirements where pilot and copilot both need to have a lifelike out the window scene. A realistic field of depth is achieved, so that the viewers can have a look into the distance, although the display area is just a few meters away.

The spatial depth of the simulation is generated through the display area: an arched mirror of large horizontal extent. This is usually a so-called Mylar Mirror consisting of a reflective polyester film, which is held in shape by a continuously running vacuum pump. The image itself is projected onto a projection screen, e.g. back projected (BPS), above the head of the pilot. The crew is looking at the reflection of the image on the mirror. Due to the shape of the mirror the light beams coming to the position of the viewer are collimated (that means they are parallelized), so that the focus is located at optical infinity. Thus, the occurring parallax effect between the viewing positions of the pilot and the copilot is negligible.® ProjectionTools have been applied in several projects with large-scale aircraft simulators which include cross-cockpit displays using collimated light. The setup presents the measurement of the scenery with various challenges. While the autocalibration of the projection screen is an easy to handle task, it is also important to consider the effects caused by the mirror. Mylar Mirrors are aspherical, especially at the edges. The image is drawn and compressed, which must be corrected.® software developer Fabian Fritz explains how distortion effects like waves and curvatures can be handled: “Based on the autocalibration of the BPS we use different modifier stacks of our tool Mapper3D to adjust the displayed image point by point from the cockpit’s point of view.” With® ProjectionTools it is possible to correct the occurring distortions and to realize an immersive virtual environment. This achieves maximum training benefit for both the pilot and the copilot simultaneously.