While controllers are commonly used with VR headsets, they are not an essential component. The primary components of a VR headset include the display, sensors, and audio.

The sensors in a VR headset are primarily responsible for tracking the user's head movement, allowing for a seamless and immersive experience by updating the virtual environment accordingly.

OLED (Organic Light-Emitting Diode) displays are commonly used in VR headsets due to their high contrast ratio, fast response time, and ability to produce vibrant colors, resulting in a more immersive visual experience.

The typical field of view (FOV) range for VR headsets is approximately 90° to 110°, providing users with a wide and immersive visual experience that enhances the sense of presence in the virtual environment.

Marker-based tracking is not a common type of VR headset tracking system. Inside-out tracking, outside-in tracking, and eye-tracking are more widely used methods for determining the position and orientation of the headset in space.

Haptic feedback in VR headsets is primarily used to provide physical sensations that correspond to virtual interactions, enhancing the sense of immersion and realism by allowing users to feel virtual objects and experiences.

Eye-tracking controllers are not a common type of VR headset controller. Handheld controllers, motion controllers, and glove-based controllers are more widely used for interacting with virtual environments.

Adjustable IPD in VR headsets serves multiple purposes, including customizing the display to the user's eyes, reducing eye strain and discomfort, and improving visual clarity and focus, resulting in a more comfortable and immersive VR experience.

720 x 720 per eye is not a common type of VR headset display resolution. Higher resolutions, such as 1440 x 1440 per eye and 2160 x 2160 per eye, are more commonly used to provide a sharper and more detailed visual experience.

The typical refresh rate range for VR headsets is approximately 90 Hz to 120 Hz. Higher refresh rates help reduce motion blur and improve the overall smoothness and fluidity of the virtual experience.

Sapphire is not a common type of VR headset lens material. Plastic, glass, and acrylic are more commonly used due to their clarity, durability, and cost-effectiveness.

Foveated rendering in VR headsets is primarily used to reduce the computational load by focusing rendering resources on the area of the display that the user is currently looking at, thereby improving performance and efficiency.

Earplugs are not a common type of VR headset audio system. Built-in speakers, headphones, and external speakers are more commonly used to deliver immersive audio experiences in VR.

Adjustable lens spacing in VR headsets serves multiple purposes, including customizing the display to the user's eyes, reducing eye strain and discomfort, and improving visual clarity and focus, resulting in a more comfortable and immersive VR experience.

NFC (Near Field Communication) is not a common type of VR headset connectivity. Wired, wireless, and Bluetooth are more commonly used to connect VR headsets to computers or other devices.