« Retinal projection requires precise alignment and optical focusing, a major engineering challenge that has pushed other companies toward simpler technologies when creating wearable displays. (Including Google, which considered retinal projection for Glass.) Avegant seems to have solved that problem in two ways: a frame that expands to accommodate different face widths and high-quality optical elements that can be individually adjusted. Where most wearable displays have crude, fixed optics, Avegant’s eyepieces wouldn’t look out of place at an ophthalmologist’s ». (via Avegant Virtual Retinal Display – Wearable tech – CNET Reviews)