iFixit has broken down Meta’s Ray-Ban Display glasses, revealing that the tech inside isn’t what makes them special — it’s the glassmaking. iFixit explains that the glass lenses use a reflective geometric waveguide system that bounces some of the light out to the wearer’s eyes at specific angles via partially reflective mirrors, which helps prevent other people from getting a glimpse of the screen when they look at you.

This works alongside the micro-projector in the right arm, a liquid crystal on silicon (LCoS) device that bounces light from three LEDs to provide a 600×600-pixel grid image. The geometric waveguide lenses differ from older “diffractive” systems used in other AR glasses, which bend and split light instead, sometimes causing the user to see little rainbow artifacts or flash “eye glow” light at onlookers. The downside is that the glass used in the Ray-Ban Display is expensive to manufacture, with iFixit speculating that Meta may be selling the glasses at a loss.

iFixit had to split the arms and frame in half to conduct the teardown, noting that Meta didn’t provide a means to clip them back together again for situations like battery replacements. “Any repairs here are going to need specialized skills and specialized tools,” iFixit teardown tech Shahram Mokhtari said in the video, adding that it’s “very clear that the first iterations of these smartglasses are going to be unrepairable.”