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.
Refresh rate
The refresh rate supported by the glasses' built-in screens, in simple terms, is the maximum frame rate that the screens are capable of delivering.
Recall that screens are provided in models for PC / consoles and in stand-alone devices (see "Intended use"). And the quality of the picture directly depends on this indicator: other things being equal, a
higher frame rate provides a smoother image, without jerks and with good detail in dynamic scenes. The flip side of these benefits is an increase in price.
It is also worth considering that in some cases the actual frame rate will not be limited by the capabilities of the glasses, but by the characteristics of the external device or the properties of the content being played. For example, a relatively weak PC graphics card may not be able to pull out a high frame rate signal, or a certain frame rate may be set in the game and not provide boosting. Therefore, you should not chase after large values and
points with a frequency of 90 fps will be enough.
USB A
The glasses must have at least one USB A connector. This is a full-sized USB connector, the same type as standard USB ports on computers and laptops. But its functions may be different, depending on the functionality of the glasses (see "Purpose"). So, in models for PCs and consoles, USB is one of the connection connectors used in conjunction with a video interface such as HDMI or DisplayPort: an image is transmitted via a video connector, and data from sensors on glasses is transmitted via a USB connection, which is necessary to change the picture and create " immersion effect. And in independent devices, USB A is used to connect various additional accessories — for example, flash drives with applications or other content. It is also possible to use this connector to charge the battery, although this method of use in general is not typical for it.
USB C
The presence in the glasses of the connector type
USB-C. This is a relatively new type of USB port, which has a miniature size (slightly larger than microUSB) and a convenient double-sided design that allows you to connect the plug in either direction. It can be found in glasses for various purposes and, accordingly, provide different ways of application. So, in models for PC / consoles, this connector is used similarly to traditional USB — with the main connection, in parallel with the HDMI or DisplayPort video interface. In standalone devices, on the other hand, USB-C is mainly used to charge the battery and connect to a computer for direct file exchange, settings management, firmware updates, etc.
Also note that this paragraph may specify the USB version, which corresponds to the USB-C connector. Nowadays, two versions are relevant — 3.2 gen 1 and 3.2 gen 2; for VR glasses, the difference between them is generally not fundamental.
Bluetooth
The presence of a
Bluetooth module in the glasses; The Bluetooth version to which this module corresponds can also be specified here.
Bluetooth is a technology created for direct wireless connection between various devices. This technology is found in all types of VR glasses (see “Purpose”), although most models with its support are independent devices. In any case, the most popular way to use Bluetooth in virtual reality glasses is to broadcast sound wirelessly. Moreover, the format of such a broadcast may be different, depending on the specifics of the glasses themselves. Thus, standalone devices broadcast the reproduced sound to external headphones. Models for PCs and smartphones may have built-in headphones, and here the sound is transmitted via Bluetooth to the glasses from an external device; Audio from the built-in microphone can be transmitted in the opposite direction.
In addition, there are other possible ways to use Bluetooth, such as directly exchanging files with another device or connecting game controllers. Such capabilities are found exclusively in stand-alone glasses; the specific functionality for each model should be clarified separately.
As for the versions, the oldest one used in VR glasses today is Bluetooth 3.0, the newest is Bluetooth 5.0. However, the differences between different versions for such devices are not fundamental; this information is provided mainly for reference purposes.
Headphone output
Availability in points
of an exit for connection of earphones. Most often, the role of such a connector is played by a standard 3.5 mm mini-jack socket.
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. Its own headphone output allows you to connect wired "ears" directly to the glasses — it is much more convenient and safer during use than connecting headphones to a computer or set-top box. However, independent devices can also have such a connector (see "Purpose").
Note that there are VR glasses with their own built-in headphones, but this option is more convenient: it allows you to select the “ears” separately, according to the user’s own preferences.
Track camera
The presence of a special external camera in the glasses; often several such cameras are installed at once, for a more complete coverage of the surrounding space.
The main function of the
track camera is to track the movement of game controllers held by the user. This makes it possible to perform various game actions with the help of appropriate hand movements — for example, to strike or shoot from a bow. In addition, the track camera can be used to "perceive" the environment — for example, building a "safe zone" in virtual space based on data on the size of the room, so that the user can see right in the game how far he can move without collisions.
