This is How Apple Glass can Project AR directly onto the Human Retina.

Apple is exploring ways to allow Apple Glass or other upcoming Apple AR devices to skip the small screen entirely and instead use a micro-projector to send images directly to the user's retina. Apple will soon have a very different meaning for the term Retina Display. Instead of a screen with such a good resolution that our eyes cannot distinguish individual pixels, there may be no screen at all. A "direct retina projector" has recently received a patent claiming that projection directly into the eye may be best suited for AR. Especially when watching AR or VR on a headset, you can avoid certain ways that can cause headaches and nausea.

“Virtual reality (VR) allows users to experience and/or interact with immersive built environments, allowing users to feel as if they are physically in that environment,” says the patent. "For example, a virtual reality system can render a stereoscopic scene to the user to create the illusion of depth, and a computer can adjust the content of the scene  in real-time to create the illusion of the user's movement within the scene." We all know this, but Apple wants to show you how a typical AR/VR system works and why things go wrong.

Then he wants to solve these problems. “When users view images through a virtual reality system, they can feel as if they are moving within the scene from a first-person perspective. “However, traditional virtual and augmented reality systems can suffer from misalignment issues that cause eye strain, headaches, and/or nausea.

Coordinated convergence mismatch occurs when a VR or AR system, based on the stereophonic convergence of the user's eyes, effectively confuses the user's brain by generating scene content that does not match the depth the brain expects, Apple states. Wearing a headset and no matter how light Apple makes it, you'll notice the screen is right in front of your face.

In fact, two screens are right in front of you. What you're looking at (augmented reality or virtual reality experience) can show you a virtual panoramic view, like someone's avatar from a distance walking towards you. AR/VR experiences direct the eye to focus at such a distance, but what is actually physically displayed is closer to the eye than ever before.

"For example, in a stereoscopic system, an image displayed to the user could be brought into focus from a farther away, while an image could be physically displayed from a closer distance,"  the patent continues.

"In other words, the eye may try to focus on a different plane of the image  or a depth of focus that is different from that of the projected image, which may increase eye strain and/or mental strain." There is another problem besides the fact that this is as obvious as the patent says it is "undesirable". Even today, there is still a limit to the amount of time a user can comfortably wear an AR/VR headset.

Of course, this has in part to do with the size and weight of the headset, but it also has to do with the "acceptance mismatch problem". Apple claims that this could reduce "a user's level of endurance (i.e., tolerance) to virtual  or augmented reality environments."