Blockbuster movies like Star Wars always feature futuristic techs such as holograms. This would be a desirable tech as it could do wonders such as Mixed Reality. Fortunately, modern gadgets have brought this concept to life – just not the way we imagined a decade ago. Latest techs allow us to place 3D graphics in front of us using our phone or headsets such as the Meta Quest and Microsoft HoloLens. Is holograms possible yet? I mean the one without headsets or phones like Sci-Fi movies. If so, how far have we progressed?
Volumetric displays, the alternative of holograms
On 3rd September 2019, Voxon Photonics, a South Australian business awed the crowd being the first company to make a live video call through hologram in BBC Radio Theatre in London, UK. The participant’s hologram was encapsulated in a small transparent box and oriented to face upwards. Only top half of his body was visible at that point.
“So what we’re doing here is we are capturing Will with a 3D camera. We’re slicing Will up to a lot of slices. And then we’re sending those slices through a super fast internet via server in the cloud. And then we’re slicing him again, project him slice by slice onto the screen with exact timing effectively” Gavin Smith, Voxon cofounder explained to BBC’s Gareth Mitchell. Confusing? Don’t worry I’ll explain in a bit.
Voxon VX1 is the company’s volumetric display that creates a Star Wars-style 3D projections – not a hologram. Holograms are produced when light is projected on a still surface. The reflected / refracted light creates an illusion of a 3D object and can only be viewed from a limited angle. Voxon’s volumetric display projects light on a fast moving surface creating an illusion of 3D object but is viewable 360º. To understand this better, lets’ have a look at this 7 year old Voxon demo – at that time known as VoxieBox.
As you can see, the rectangle surface is jumping up and down rapidly. At the bottom they are projecting light but in a slightly different way. Imagine slicing the 3D human image into 100 slices from bottom to top. Lets’ also imagine the rectangle surface is moving slowly. When the rectangle surface is at the bottom and lifts slightly (1/100 of its highest jump) the projector projects the first slice of the human. When the moves a little further up (2/100 of its highest jump) the projector switches to project second slice of the 3D human. This repeats all the way to the 100th slice. Because the human eyes are slow, this super fast process appears to form a 3D image suspended on air.
Are the Sci-Fi holograms possible with volumetric displays?
For now, it doesn’t seem like so. In the film Star Wars, most of the time characters would be able to walk through the holographic displays. Shoving your finger through the VX1 could possibly break your finger. You could control the displays through an external device just like in Star Wars.
In Iron man, Tony Stark spends a lot of time brainstorming with holographic displays. The difference is he could move it around using his hands like a real object. This is a perfect example of Mixed Reality. However, this is also not possible with this technology for the same reason you can’t walk through it.
We still have a long way to go before a more realistically interactive 3D projection arrive on market. Until then, phones, headsets, glasses and possibly contact lenses are our current option to Mixed Reality.