Speaker 1: A breakthrough. An augmented reality does something that appears to
Speaker 1: be simple but in fact is really tricky and lets
Speaker 1: you hide a virtual object behind a real one. I'm
Speaker 1: Jonathan Strickland, and this is tech stuff. Daily. Augmented reality
Speaker 1: involves using some form of display or output device to
Speaker 1: overlay digital information on top of the real data we
Speaker 1: encounter out in the physical world. The typical representation of
Speaker 1: this is some form of goggles or handheld display that
Speaker 1: overlays computer generated imagery on top of a view of
Speaker 1: our physical surroundings. This is just one type of augmented reality,
Speaker 1: but it's a common one. There are numerous smartphone apps
Speaker 1: that will let you look at the world through your
Speaker 1: smartphone screen. You're looking at a live video feed captured
Speaker 1: by the smartphones camera. The app will overlay some sort
Speaker 1: of digital information on top of your live video view
Speaker 1: of the world. It might be directions, such as an
Speaker 1: arrow pointing to the indicating you need to make a
Speaker 1: left turn to get to your pizza parlor. Or it
Speaker 1: might be a virtual character in a game, perhaps a
Speaker 1: big boss you have to battle before you can cross
Speaker 1: the threshold of your local pizza parlor to get a
Speaker 1: pepperoni slice. It's lunchtime. But one challenge a our developers
Speaker 1: have faced is called occlusion. Occlusion in this sense is
Speaker 1: all about an object blocking another object in the real world.
Speaker 1: If one opaque object passes behind another, of course we
Speaker 1: lose sight of it for a moment. For example, if
Speaker 1: we play hide and seek and you go stand behind
Speaker 1: a tree. When I look around, I'm not going to
Speaker 1: see you, assuming of course you're using the tree to
Speaker 1: block my view of you. And if you walk in
Speaker 1: front of the tree, I'll see you, but I won't
Speaker 1: be able to see the parts of the tree you're
Speaker 1: covering up. This is obvious. We experience this every day,
Speaker 1: so I know I'm not sharing anything new with you.
Speaker 1: But now let's imagine we're using an augmented reality application
Speaker 1: and hardware. We have to teach this system to recognize
Speaker 1: the border of real world objects within view. It also
Speaker 1: must recognize the relative distance of those objects from the camera,
Speaker 1: as well as the virtual distance between the display and
Speaker 1: the virtual object. Only then can such a system allow
Speaker 1: for a virtual object to pass behind or in front
Speaker 1: of a real one and have it reflected in the
Speaker 1: display so it looks like it's really happening in front
Speaker 1: of your eyes. This is a non trivial problem. A
Speaker 1: research team at the University of Arizona's College of Optical
Speaker 1: Sciences have a prototype display that tackles this issue. Their
Speaker 1: display allows for a virtual object to be blocked by
Speaker 1: a real world object. It also allows the virtual object
Speaker 1: to block other objects that are behind it. That behind
Speaker 1: was in air quotes, because obviously the virtual object isn't
Speaker 1: really in the physical space at all. According to Professor
Speaker 1: Hong Hua, the display takes the view of the real
Speaker 1: world and with lenses, images it upon a spatial light modulator.
Speaker 1: These are devices that can alter or modulate polarization, amplitude,
Speaker 1: and phase of light beams. They often will modify the
Speaker 1: intensity of a lightbeam, though more advanced ones can do
Speaker 1: all sorts of funky things with light. The team used
Speaker 1: a spatial light modulator to create a mask that blocks
Speaker 1: out the bit of the real world that the virtual
Speaker 1: object will inhabit. This modulated image is what then reaches
Speaker 1: the display that you can see. One thing that's necessary
Speaker 1: to make all this work is a depth sensor. Without
Speaker 1: a depth sensor, the system cannot know which objects are
Speaker 1: closer to the lens and which are further away. There
Speaker 1: needs to be a way to measure that distance and
Speaker 1: then calculate where a virtual object should fall based upon
Speaker 1: that objects virtual distance from the viewer. This is a
Speaker 1: big jump from just overlaying a digital image on top
Speaker 1: of a video view of the world. This is incorporating
Speaker 1: computer generated imagery into a real environment as if it
Speaker 1: too were just as real. Law says that it will
Speaker 1: likely be sometime before we see this capability built into
Speaker 1: consumer headsets. She says her team's solution wasn't exactly sleek
Speaker 1: and sexy. They were just trying to get a system
Speaker 1: that worked. Refining that system into something more consumer friendly
Speaker 1: will take some time to get it down to a
Speaker 1: format that might fit in, say a pair of special
Speaker 1: glasses will take even more time, but the foundation is there.
Speaker 1: To learn more about augmented reality, mixed reality, and all
Speaker 1: sorts of other types of reality. Subscribe to the Tech
Speaker 1: Stuff podcast every Wednesday and Friday. I look at big
Speaker 1: topics and tech and really explore how they work and
Speaker 1: why they're important. I'll see you again soon.