The HTC Vive XR Elite 'Full Face Tracker' addon is now available, priced at $200.
The addon magnetically attaches underneath the facial interface of Vive XR Elite, connecting to the secondary USB-C port next to the headset's right lens, likely placed there specifically for this accessory.
It features two 120Hz eye tracking cameras and one 60Hz lower face tracking camera.
The lower face tracking camera tracks up to 38 points on your face in real-time, across the lips, teeth, tongue, cheeks, nose, and chin. HTC claims this means "even subtle facial expressions are accurately portrayed, and spoken words match facial expressions in real-time".
As well as driving your avatar's eyes, the eye tracking cameras are also used for foveated rendering, and to measure your IPD for automatic lens separation adjustment so you don't have to measure or guess your IPD to get the optimal visual experience.
HTC says a software update to support the addon will release for Vive XR Elite tomorrow, and developers can use either its Vive Wave SDK or OpenXR to access the face and eye tracking data.
The company already sells separate face and eye tracking addons for its other standalone headset, Vive Focus 3, which is solely aimed at businesses and has a bulkier design but higher resolution and wider field of view.
Meanwhile, Meta's CTO shot down the prospect of an eye tracking addon for Quest 3 back in November, saying there's "not really a credible way to do eye tracking or upper-face tracking underneath the headset as an accessory" for its headset.