VR/AR FAQs

When comparing Fresnel and Pancake lenses for VR, both types have their pros and cons. Fresnel lenses are widely used due to their affordability and wide field of view. However, they are bulkier and can introduce image distortion issues, including god rays and chromatic aberration.

On the other hand, Pancake lenses, although newer, offer significant improvements in VR headsets. They are lighter, thinner, and largely eliminate issues such as god rays and chromatic aberration. However, they do have a slightly smaller field of view and require brighter displays, which could potentially drain battery life faster.

In terms of overall visual quality and user comfort, Pancake lenses are generally superior. However, they are currently more expensive to produce, which may impact the cost of the headset. In conclusion, while Pancake lenses technically offer a better VR experience, the choice between the two should also take into account other factors such as the headset's specifications and your budget.

Here lists some modern VR headsets that do feature Pancake lenses on board.

· Meta Quest Pro

· Pico 4

· Metavision Particle (3DoF)

· Metavision 8K VR Headset (3DoF)

Traditional and Fresnel Lenses: These lenses focus the image from the digital display to the user's eyes. Fresnel lenses are lightweight and offer a wider field of view due to their design featuring a series of concentric grooves. Oculus Rift and HTC Vive use Fresnel lenses in their VR headsets.

Pancake Optics: This technology utilizes 'pancake' lenses, which bounce light back and forth to elongate the optical path in a compact space. This design enables thinner and lighter headsets.

There are many cutting-edge VR headsets use Pancake Optics in their VR headsets including PICO 4, Meta Quest Pro, Metavision Particle, and Metavision 8K VR.

Aspheric Lenses: These lenses, which are not uniformly curved, are used to reduce optical aberrations and provide a clearer image. The original Oculus Rift CV1 employed aspheric lenses to reduce optical aberrations

Hybrid Lenses: Some VR systems use a combination of different lens types to optimize both the size and image quality of the device.

Waveguide Optics: This technology involves directing light through thin, transparent sheets (waveguides) and then into the user's eyes. This technology is used in devices like the HoloLens 2 from Microsoft, and M51 from Metavision.

Birdbath Optics: This design involves reflecting a display off a curved mirror onto a semi-transparent mirror, then into the user's eyes. This approach can increase the field of view and image brightness. Metavision’s M30, M35 and M53 use Birdbath optics in the glasses.

Prism Optics: These optics, used in devices like Google Glass and Metavision M6, use a prism to reflect light into the user's eyes, overlaying digital information onto the real world.

Light Field Displays: An emerging technology in AR, light field displays simulate the behavior of light to produce 3D images with realistic depth, enhancing the sense of immersion in AR environments.