Engineers from Intel created a prototype of the VR helmet with a field of view of 180 degrees horizontally, which in itself is rare for such devices, and also much more compact design than the existing counterparts. The article was presented at the IEEE VR 2020 and published on the website of the authors.
There are several key parameters of the VR helmets, responsible for the realism and sense of immersion in the virtual world: the pixel density in the screens of the helmet, the field of view and image refresh rate. The pixel density and the refresh rate is gradually increasing with the development of production technologies of screens, and with a field of view, the situation is more complicated, because to increase it you need to develop a new design of lenses or screens. Currently, the popular VR-helmets field of vision horizontally is 90-110 degrees, whereas in humans it is 210 degrees. There are several niche VR-helmets (Pimax, Xtal and StarVR) with a field of view roughly equal to a human, but they use very large optical elements and screens, so they are very bulky (about twice as wide as the head).
Ronald Azuma (Ronald Azuma) and his colleagues from the research division of Intel was able to increase the field of view VR helmet almost to the level of man, without increasing the size of the entire device. The optical system consists of a pair of lenses and two arrays. Each of the arrays consists of dozens of separate lenses. The array consists of ten identical rows of five lenses, but in this number the geometry of the lenses varies and changes from the Central lens to the top and bottom. This allows you to significantly improve the image quality in the upper and lower parts of the field of view. Horizontal field of view of a new VR helmet is 180 degrees.
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Because the array of lenses strongly curved, engineers used curved screens. They took out the two smartphones Samsung Galaxy S9. In original form they are covered with glass and not moving, but, as other screens with curved edges, the matrix is flexible. Separating the glass, the engineers had the opportunity to bend the screen at their task and have recorded their near lenses.
In its current form, the prototype has several limitations. First, the boundaries between the lenses distort and partially visible to the eye. Potentially, this can be corrected by reducing the lens, by analogy with the microlenses in the display. Second, because the developers used the screens of smartphones, the drivers for them, as with other curved screens of small size, not available, so they had to attach both the smartphone and the helmet. But this restriction applies only to research projects and is not an obstacle for major device manufacturers.
In 2018, the Oculus, one of the main developers of the VR helmets, showed the prototype helmet with a mechanical focusing system. It can move the screens closer or further from the user, and to change the sharpness of different virtual objects.