Pixels per degree (PPD)

Pixels per degree, or PPD, is a way to describe how sharp a VR headset looks. Instead of counting the total pixels on the panel, it asks how many pixels cover each degree of your view. A headset with a high-resolution display but a very wide field of view can end up with a similar PPD to a lower-resolution headset with a narrower view.

Why it matters

PPD decides how readable small text is, how clean distant objects look, and how visible the gaps between pixels are. Low PPD makes the image look soft and can make the screen-door effect easier to see. A figure of around 60 PPD is often cited as roughly matching normal 20/20 visual acuity, and consumer headsets still sit below that.

Center versus edge

Lenses do not spread pixels evenly, so PPD is usually highest in the center of the view and lower toward the edges. Manufacturers that publish a PPD figure normally quote the center value. Because of this, PPD is best used as a rough comparison together with lens quality, display type and real-world clarity reports rather than as a single deciding number.