FOV, what is it?

Field of View (FOV) is a crucial aspect of any optical device, including Pimax headsets. While Pimax has advertised the maximum FOV of its headsets, there have been instances where users have experienced a discrepancy between the promoted and actual FOV. In this blog, we will explain why there can be a variance in FOV in Pimax headsets and what factors affect it.

FOV in Pimax headsets

FOV is divided into HFOV (horizontal), VFOV (vertical), and DFOV (diagonal). At Pimax, when we talk about FOV, we use DFOV as a measurement. So this is 200° for the Pimax 8KX and 140° with the Pimax Crystal (when using 35PPD lenses).

• – HFOV: Horizontal FOV
• – VFOV: Vertical FOV
• – DFOV: Diagonal FOV

In terms of theoretical pure mathematics, it can be seen from the figure that HFOV is determined by Focal Length and sensor width (W), and VFOV is determined by Focal Length and sensor height (H). DFOV is jointly determined by Focal Length, W, H.

Why?

However, there are many factors that affect the FOV number, such as individual differences, external conditions, and design and manufacturing limitations. These affect not only in Pimax headsets, but all VR headsets. Let’s take a closer look at each of these factors.

1: Personal Differences

First of all, there is no denying that FOV varies from person to person. There is a limit, based on what is rendered and optics. As for maximum FOV, the eyes need to be at an optimal distance from the lenses, which can be hard to achieve with many face shapes and head shapes. That’s why some individuals cannot get the number we promoted.

2: External Conditions

In addition, the FOV of the human eye is not fixed, but changes according to external conditions such as light intensity and the distance of objects. Therefore, some assumptions and trade-offs may need to be made when simulating the FOV of the human eye. The FOV of the actual experience depends on many factors such as the user’s interpupillary distance, the distance between the eyes and the lens, and the testing method. The test data of personal use of three-party tools is only recommended as a relative reference value. Pimax has tested over 100 individuals to measure the FOV of its headsets, and the promotion FOV numbers for the Pimax 8KX and Pimax Crystal are what the company obtained. However, users may experience slightly different FOV numbers based on individual differences and the actual application. In other words, it’s difficult to guarantee that every user can achieve the promoted FOV numbers due to several factors that affect the FOV experience.

3: Design & Manufacturing Limitations

During the design and manufacturing of Pimax headsets, there are different aspects of limiting factors that can affect the FOV, such as resolution, brightness, contrast, light transmittance, image artifacts, distortion, and uniformity. And other non-display issues such as: eye zone, size, weight, battery, cost, durability, etc of the headset. In addition, the improvement of the field of view will also put forward higher requirements on the computing power and power consumption of the equipment.

Conclusion

Overall, Pimax’s careful design offers a more efficient FOV for individual users without sacrificing pixels per degree or any distortion. While it’s challenging to accurately measure and describe FOV, Pimax’s testing and user feedback confirm that the FOV of the Pimax Crystal is larger than other popular headsets in the market.