One of the most critical components of a Virtual Reality glasses are its lenses. They are the ones that provide us with a good or bad experience in the virtual world, they allow us to access it by connecting our eyes to the screen and adjusting to our comfort, correcting the angles of the light rays that reach us from the screen so that the experience is pleasant.
If until now, the use of Fresnel lenses in Virtual Reality viewers had been standardized, we are seeing more and more viewers incorporating Pancake lenses in their designs. Why are Pancake lenses gaining ground? We take a look at it below.
Fresnel, the first small lenses
The first to incorporate Fresnel lenses were viewers such as HTC Vive and the Oculus Rift CV1, one of the most popular viewers that include them are the Oculus Quest 2. A first step towards lighter headsets with more elegant designs, which in addition to the aesthetic component, improve vision, minimizing the space between pixels and thus mitigating the door effect, thanks to the use of these lenses.
Although the design of the French physicist, Augustin-Jean Fresnel, has achieved a better aperture and a short focal length, getting rid of the weight and volume of predecessor lenses, it has not overcome one of the limitations in its use applied to Virtual Reality glasses, the glare effectknown as the glare caused by excessive brightness accompanied by discomfort by reducing the visual quality of the user.
Fresnel lenses work as a ring of crystalline prisms that reflect refracted light, which in order to work properly require space between the screen and the lens itself. This results in a larger and heavier viewfinder than Pancake lenses.
Pancake, less bulk and more lightness
With the incorporation of Pancake lenses in Virtual Reality glasses, the space between the lenses and the screen has been reduced, without affecting the user's comfort. These lenses are known for their use in the world of photography and are characterized by their lightness. That's why Pico's new premium all-in-one viewfinder, the PICO 4Pico's new premium all-in-one viewfinder, the PICO 4, weighs only 295 grams - as light as a soda can. Unlike Fresnel lenses, which in a viewfinder such as the Meta Quest 2, also known as the Oculus Quest 2, weigh 503 grams.
Pancake lenses are much more compact, reduce the volume of the viewfinder considerably compared to Fresnel lenses, and also eliminate the glare effect (described above), they provide better image quality and lower cost.
Finally, the optical efficiency: in the case of Pancake most of the light is blocked and, therefore, there could be a color difference between one viewfinder or another depending on the lenses, although in the case of PICO 4 they manage to achieve a saturation rate of 85%. These features are also shared by the business version of Pico's new PICO 4 Enterprise viewer, the PICO 4 Enterprise, which also features this type of lens.
What we are sure of is that, day by day, scopes are improving in usability and comfort.s are improving their usability and comfort for the user, with Virtual Reality glasses becoming lighter and more compact.
And you, which glasses do you prefer?