I’m not sure if my question fits this forum very well, but I figured the users here will have the relevant knowledge.
That being said I want to better understand what VR headset developers mean by field of view of the headset. Most VR headsets claim to have a “field of view of 90 – 110 degrees”. However a research paper calculated the physical field of view of many popular VR headset and found horizontal fields of view about 40-55 degrees, around half of number stated in the specs. For the calculation they only used the size (=width) of the display, and the distance to the eye. To my surprise (probably due to a lack of understanding) they did not include the strength of the lens (lenses?) in the calculation.
I am trying to understand whether and how the strength of the lens influences the perceived angle (or field) of view in this context. If the field if view would be 40-55 degrees for each eye, then the total field of view should be similar since both eye are presented more or less the same image. Am I missing something or are VR companies just proving misleading specifications?
Below is a visualization from the paper.
Reference to the paper (its behind a paywall unfortunately):
Lynn, M. H., Luo, G., Tomasi, M., Pundlik, S., & E Houston, K. (2020). Measuring Virtual Reality Headset Resolution and Field of View: Implications for Vision Care Applications. Optometry and Vision Science : Official Publication of the American Academy of Optometry. https://doi.org/10.1097/OPX.0000000000001541