Why Can't VR Glasses Have a Higher Field of View?

The magic of virtual reality (VR) lies in creating a seamless, realistic experience that immerses the user in a different world. However, one of the challenges in VR technology is achieving a higher field of view (FOV).

Is a Higher FOV Always a Good Thing?

Before diving into the reasons why higher FOV may not be possible, it's important to understand why FOV matters. A higher FOV means a wide-angle view, allowing the user to see more of the virtual environment at once. This is particularly important in VR, as a narrower FOV can create a more limited sense of spatial awareness, making users more aware that they are in a virtual space rather than a real one.

The Technical Challenges: Why It's Expensive

The primary reason why VR glasses often don't feature a higher FOV is the cost and complexity involved. Achieving a wider FOV requires a combination of high-resolution screens and large lenses, which in turn necessitates a more complex apparatus to hold everything securely and to minimize distortion.

High-resolution Screens

A high-resolution screen is crucial for a VR experience. Each pixel must be small enough so that it doesn't detract from the realism of the virtual world. However, producing a screen with a high enough resolution to cover a larger FOV is no small feat. The current technology is pushing the boundaries, but it comes at a significant cost. For example, high-resolution screens in current VR headsets often use panels that are very fine-grained, with each pixel contributing to the overall image quality.

Lens Size and Design

The lenses in VR glasses are central to the user experience. Large lenses are necessary to provide a wider FOV, but larger lenses also mean more complex optics. The design of these lenses must be precise to avoid distorting the image. If the lenses are too large or not properly aligned, it can lead to a disappointing experience with artefacts and unnatural images. The current technology allows for some trade-offs, but achieving a wider FOV with minimal distortion is challenging.

Complex Apparatus for Holding Things Together

Beyond just the screen and lenses, the apparatus that holds everything together is also essential. A VR headset needs to be sturdy yet comfortable, with a design that allows for a wide range of motion without causing discomfort or fatigue. The increased complexity of a wider FOV design adds to these challenges, as it requires more robust components and potentially a heavier overall product.

Consequences of Lower Resolution Screens

If a high-resolution screen is not used, the user may see individual pixels, which can significantly undermine the immersion and realism of the virtual experience. This pixelation can be particularly noticeable around the edges of the FOV, as the larger lenses used to increase the field of view can magnify the resolution limitations. Poor pixelation can break the suspension of disbelief, making the user more aware of the virtual nature of their surroundings.

Conclusion: A Balancing Act

The quest for a higher FOV in VR glasses is complicated by the interplay of multiple technical challenges. While it is possible to design VR glasses with a wider FOV, the process is costly, and the end result must balance the need for superior visual quality with the practical considerations of comfort and functionality.

As technology advances, we can expect to see improvements in VR design. However, for now, the trade-offs between a wider FOV, high resolution, and overall comfort are a key factor in the limitations of VR glasses.