Field of view
The viewing angle provided by virtual reality glasses is the angular size of the space that falls into the user's field of view. Usually, the characteristics indicate the size of this space horizontally; however, if you need the most accurate information, this point needs to be specified separately.
The wider the viewing angle — the more the game space the user can see without turning his head, the more powerful the immersion effect and the less likely that the image will be subject to the "tunnel vision" effect. On the other hand, making the field of view too wide also does not make sense, given the characteristics of the human eye. In general, a
large viewing angle is considered to be an angle of 100° or more. On the other hand, there are models where this indicator is 30° or even less — these are, usually, specific devices (for example, drone piloting glasses and augmented reality glasses), where such characteristics are quite justified given the overall functionality.
Lens distance adjusting
The ability
to move the lenses of the glasses back and forth, thus changing their location relative to the screen and the user's eyes. The specific meaning of this function can be different: it can adjust the angle of view (so that the screen fits completely in the field of view and at the same time is not too small), play the role of diopter correction (which is important for users who wear glasses) or focus, change the setting interpupillary distance (see below), etc. These nuances should be clarified separately. However, anyway, this function will not be superfluous — it makes it easier to adjust the glasses to the personal characteristics of the user.
Headphones
The presence
of your own headphones in the design or delivery of virtual reality glasses.
A full-fledged "immersion" in the virtual world requires not only a picture on the screen, but also an appropriate sound accompaniment, for which headphones are the best option. However, glasses take up quite a lot of space on the head, and not all “ears” can be comfortably combined with them (this is especially noticeable on large over-ear headphones). In addition, when connecting headphones with a wire, there may be problems related to the length and/or location of the audio cable. Thus, some models provide this function. These models can have any purpose (see above); most of these are for PC/console glasses, but headphones are also popular in standalone devices. Also note that some glasses use speakers located in the ear area; such speakers are also considered headphones in this case.
An alternative to the bundled "ears" is a headphone output; however, there are models with both functions at once — either folding / removable cups or the simplest speakers mentioned above play the role of headphones in them.
Controller
The presence of a
controller — an additional control device — is included in the delivery of glasses.
The design and functionality of such an accessory may be different. So, the most popular option is specialized game controllers with a characteristic look — a handle with an analogue lever and buttons. There can be two such handles at once, under both hands; and in some models they are also used to control gestures. The movement of the hands can be tracked both by sensors in the controllers themselves and by cameras on the glasses. There are also simpler solutions — for example, portable gamepads or remote controls for controlling video playback.
