The evolution of flight simulation and virtual reality (VR) technology has significantly advanced the immersive experience for enthusiasts, professionals, and aviators alike. Central to this progression are pancake lenses, which can be found in new VR headsets (such as the Meta Quest 3). The technology plays a pivotal role in mitigating parallax errors, enabling users to focus onto infinity.

Similarities between VR Headsets and Collimated Displays: Both VR headsets and collimated displays share the objective of providing a lifelike, immersive experience. They achieve this by simulating the environment realistically while allowing users to interact seamlessly within the simulated world. The integration of pancake lenses in VR headsets mimics the visual cues experienced in the real world, enhancing the sense of depth and distance.

Pancake lenses reduces the overall size of the VR system and improves in lens clarity. Junyu Zou, Tao Zhan, En-Lin Hsiang, Xinpeng Du, Xiaoming Yu, Kun Li, and Shin-Tson Wu, “Doubling the optical efficiency of VR systems with a directional backlight and a diffractive deflection film,” Opt. Express 29, 20673-20686 (2021)

Understanding Collimated Displays: Collimated displays, commonly utilized in professional flight simulators, project images onto a surface or lenses in such a way that light rays are parallel when they reach the observer’s eye. This setup eliminates the need for the eyes to converge, mimicking the natural viewing experience and reducing eye strain.

With parallel rays the eye accommodates for distance and the ciliary muscles which control the lenses, relaxes

A collimated display can be incorporated into an enthusiast flight sim setup by using large fresnel lenses or by using mylar film and precise calculations.

The Role of Pancake Lenses: Pancake lenses, renowned for their thinness and unique optical properties, serve as a key component in achieving collimation within these systems. These lenses, often aspheric in design, help in redirecting light rays to ensure they remain parallel, enhancing the perception of depth and enabling users to focus at optical infinity.

Eliminating Parallax Error: Parallax error, a common issue in conventional displays, refers to the displacement of an object’s apparent position when viewed from different angles. Collimated displays, by presenting images with parallel light rays, minimize parallax errors. This accuracy is crucial in flight simulation, where precise depth perception and spatial awareness are paramount for training and simulation purposes.

One of the remarkable features facilitated by collimated displays and pancake lenses is the ability to focus on objects at optical infinity. By ensuring light rays reaching the eye are parallel, these systems replicate the natural visual experience, enabling users to focus effortlessly on distant objects, mirroring the way our eyes perceive far-off scenes in the real world.

Effects on User Experience: The incorporation of collimated displays and pancake lenses in VR headsets and flight simulation systems significantly enhances the user experience. By eliminating parallax errors and enabling focus on infinity, these technologies create a more immersive, realistic, and comfortable environment for users, whether they are pilots in training or enthusiasts exploring virtual worlds.