Understanding How VR Headsets Work

Virtual reality might look like black magic, but the truth is every headset is a carefully designed product, mixing cutting-edge tech with over a few clever tricks designed to make you forget about everything except for what is on the screen. We are breaking down how these headsets work and having a look at the individual components which produce virtual reality such a convincing experience.

The lens is among the most vital elements of what makes virtual reality so persuasive. These lenses fool your eyes into thinking you're taking a look at a considerable depth of distance rather than just two horizontal displays inches away. The lens achieves this by focusing the light on making it appear like the screens were an infinite distance away.

Many headsets have chosen to utilize specific Fresnel lenses, which achieve the same impact as heftier curved lenses with much less material using thin, circular arrays of prisms. These lenses also magnify the headset's built-in screen, so you don't observe the advantages of the displays, which makes the picture encompass your whole field of view.

High-performance screens are another vital element in convincing virtual reality. They have to have a density of pixels to show clear pictures but also exhibit them in a quick enough rate to generate motion in VR smooth.

High-end headsets utilize dual screens to make a stereoscopic 3D. Both the HTC Vive and Oculus have chosen for two 1080x1200 screens, one for each eye, which are designed to display images at 90 frames per second -- providing users smooth motion and a broad 110-degree field of view that encompasses a lot of your selection of vision.

High-end headsets also use dual displays to make a stereoscopic 3D effect similar to the Nintendo 3DS. Each screen shows a slightly offset image to each eye which our mind then joins together into a single picture, creating an illusion of depth in the procedure.

The Samsung Gear VR gives a low-cost entry point using a smartphone as the screen, sacrificing field of view and graphics fidelity for a wireless headset. Both replaceable lenses are what generates the stereoscopic image in this example.

Because each has a different distance between the middle of their students (known as the interpupillary distance), headsets must contain options for adjusting the lenses to be able to match the spacing of our eyes to accomplish the appropriate stereoscopic 3D effect.

The Oculus Rift also sports hybrid Fresnel lenses which are shaped to have variable levels of attention throughout the glass, permitting you to move the headset up or down to adjust focus and find that sweet spot.

To be able to display accurate graphics, headsets must track the motion of your mind as you look around to submillimeter precision. This is accomplished via a variety of built-in detectors. Together with the data of all of these detectors, headsets can attain right"six degrees of freedom," allowing for the monitoring of every conceivable motion the headset could create.

Magnetometers measure Earth's magnetic fields to always know where"magnetic North" is. By discovering this, it may always make sure it's pointed in the appropriate direction, preventing"drifting" mistakes where the headset believes it is facing one direction when it is facing another.

Accelerometers have a few applications, like discovering gravity to understand up which direction is. This is most commonly seen when rotating your smartphone and the display adjusts to reflect the new orientation. As their name suggests, accelerometers may also measure acceleration along an axis, providing useful data for how fast an object is moving.

Gyroscopes provide a much more okay measurement of the rotation of an object by monitoring subtle changes in orientation along an axis, like tilting your head slightly or nodding.

The Samsung Gear VR forgoes more advanced infrared monitoring methods to utilize an inertial measurement unit (IMU), which can be somewhat of an all-purpose apparatus using magnetometers, accelerometers, and gyroscopes. Unlike in many smartphones, this IMU is made especially to decrease lag and enhance head tracking performance.

Both the Oculus Rift and HTC Vive use infrared lasers to monitor the motion of the headset, but everyone has their method.

All this is completed nearly instantly, meaning there is almost zero lag.

Oculus employs the "Constellation" IR camera that sits on your desk and monitors blinking IR lights positioned on both the front and rear of the Oculus Rift. If using Oculus Touch controls, another camera is needed to reduce confusion when monitoring the lights on both the headset and controls. Each sensor is tracked separately, and your personal computer gathers all that information to render images which are positionally suitable for where you are looking at any given moment. All this is completed nearly instantly, meaning there is virtually zero lag between when the coordinates of every IR sensor is recorded, processed, and the picture is displayed.

The HTC Vive utilizes"Lighthouse" IR emitters, which are placed at the corners of a play area and rapidly fire sweeping lasers throughout the room that IR detectors on the Vive pickup and use to triangulate its position in space. The system works similarly to the Oculus but switches the functions of each device by having the Lighthouses act as emitters and the headset.

No comments