Pepper’s Ghost and similar techniques are being used to create 3D video depictions of people and objects. Increasingly referred to as holograms, these visual displays are emerging as a new option for videoconferencing, distance learning and product development. Tim Kridel explores the technologies and benefits.
Nearly a half-century ago, the British Thomson-Houston company applied for a patent on the technology best known for its ability to produce holograms. But holography remained more or less a niche market until 2012, when it was used to bring the late rapper Tupac Shakur back for a seemingly live performance at the Coachella Music Festival.
But perhaps the biggest indication that holograms have finally gone mainstream is that politicians and professors are now using them. In the US, presidential candidate Andrew Yang plans to use holograms to hold campaign rallies in multiple states simultaneously. Holograms also played a major role during the run-up to the 2018 Pakistani general election, where mobile systems were driven around to remote towns for one candidate’s nightly rallies. That was cheaper and more secure than having the candidate make those visits in person.
“They reckoned that with 20 trucks, they reached 20 million people in a month,” says Rory Elliot, head of EMEA at ARHT Media, which provided the technology.
Holograms are still projected, like your normal light-based projectors. The only difference is that we use lasers, but the same principles apply.
- Bruce Dell, Euclideon Holographics
Euclideon Holographics is an example of how some vendors also are marketing holography systems as an alternative to traditional cave automatic virtual environment (CAVE) systems. The company is also set to launch hologram walls.
“Their holograms will be 3.6m(l) x 2m(h),” says Bruce Dell, CEO and founder. “They will project out of the wall by up to a metre, and project into the wall by up to a kilometre, which would be as if you were looking out of a window.”
One example use case is an automaker that wants to use its existing computer-assisted design (CAD) or Revit data as the foundation for holograms.
“We would export it as an OBJ Polygon file, where then it would immediately load into the hologram wall,” Dell says. “You then would be able to see it as a hologram, and in this case, poke your head inside the car and look around.”
In the UK, Imperial College Business School is using holography for a variety of applications. One example is bringing in guest speakers from Los Angeles, New York and London.
“It will break down the limitations of traditional teaching by creating an interactive experience that benefits both students and academics,” says Dr. David Lefevre, director of the school’s Edtech Lab. “Rather than replacing or reducing real-life lectures, the hologram technology will provide greater flexibility for academics by enabling them to continue teaching whilst travelling, ensuring consistency and quality for students. The technology will also widen the scope for Imperial to invite global leaders and influencers from industry to give talks to students, therefore enriching the learning experience.”
What’s the difference?
If those goals and benefits sound familiar, that’s because they are. For decades, higher ed has used everything from Skype to enterprise-grade videoconferencing systems to bring guest lecturers into classrooms. A major reason is because those people are in high demand, and video is the only way they accommodate all those requests without travelling 24/7/365.
“Education probably is going to be our biggest client,” says ARHT’s Elliot. “They send their professors all over the world for a half-hour conference [presentation]. It costs a fortune. Everyone is tired of it.”
The same lament is heard ’round business world, where videoconferencing has been widely used for decades. Which begs the question: In both education and business, what do holograms do that traditional video doesn’t?
For starters, there’s the wow factor. Although most consumers have seen holograms once or twice, they’re still relatively rare. So in the case of advertising on digital signage, for example, their novelty is a major benefit because they increase the likelihood that passers-by will stop to watch. And in a classroom, the novelty of seeing a guest lecturer appear by hologram could help students pay more attention to what he or she is saying.
Celebrities are in particularly high demand, and a video appearance can seem like a let-down. Holograms can help overcome that by delivering a more lifelike presentation. Take the example of Aquaman star Jason Momoa, who needed to be in three places at once in December 2018.
“He was rehearsing for Saturday Night Live [in New York City],” says Larry O'Reilly, ARHT Media CEO. “On Thursday night, he just went to a different studio at 30 Rock, and we beamed him into Mexico City for fan engagement and media events at the IMAX theatre there. The next night, we beamed him into Comic-Con Brazil, where he addressed over 3,000 people live.”
Despite their rich user experience, holograms don’t necessarily require a lot of bandwidth. That helps enable portable systems such as the ones used during the Pakistani election.
“We capture in 4K, but typically presentation is in HD,” O'Reilly says. If people want 4K, they can do it. We just need 10 Mbps up and 10 Mbps down to do a live stream.”
Beyond the novelty factor
After each event, Imperial College’s EdTech Lab surveys students and speakers about their experience, including how it compares to traditional videoconferencing.
“Students comment that both a realistic, in-person presence and the fact that hologram speakers were able to interact with students by asking and answering questions, contributed to their feeling of strong engagement during the seminar,” says Nai Li, Imperial College Business School educational researcher. “Students believe that these concepts are linked, the more realistic in-person instructor presence afforded by the holographic videoconferencing fostered engagement, which made the seminar more enjoyable.
“Instructors also stated their experience to be a positive one, supporting the premise that holographic videoconferencing can facilitate and enhance the delivery of presentations. One advantage offered was that holographic videoconferencing technology provides an experience closer to that of a face-to- face presentation and that this enhanced communication.”
But the surveys also suggest that the novelty is a big factor.
“Almost all students reported that the first time they ever attend a holographic event, a positive response arising from a sense of novelty was present,” Li says. “This may suggest that benefits of holographic videoconferencing may be short term.
“However, we argue that benefits relating to the enhanced degree of teaching presence will be sustained. In particular, the use of holographic videoconferencing increased students’ sense of ‘teaching presence’: a component of the Community of Inquiry Framework shown to aid motivation and engagement.”
Imperial uses technology from ARHT, which is heavily focused on the education market. But the company is also getting a lot of traction in the enterprise market.
“It’s not about having a one-off ‘wow’ moment: ‘Okay, we’ve done a hologram,’” O'Reilly says. “The real application is when we overcome a business issue that they have, so they want to use it again and again and again.”
Creating an illusion
The term “hologram” is a catchall for a wide variety of techniques, such as Pepper’s Ghost. So for integrators and other AV firms that want to add holography to their portfolio, one obvious consideration is how each vendor achieves the effect.
“The hologram technology we have requires a very different and more precise setup compared with traditional methods of videoconferencing or remote presentation systems,” says Andrew Parry, Imperial College Business School online learning video producer. “The capture space itself needs a minimum distance of about 8 m between camera and subject so that lens distortion can be minimised or eliminated altogether.
“The height of the camera is also important. The camera needs to be positioned close to the floor tilting slightly up at the subject. These two things ensure that the final result at the display end is an accurate representation in terms of body shape and dimensions.”
Lighting is also important.
“You’re trying to create a clear outline around the subject so that they stand out from the black drapes arranged behind—and therefore produce a clearly defined image on the display screen,” Parry says. “There are four lights placed behind the subject which backlight everything, including shoes. There are also two lights arranged in front of the subject. There’s an optional light that can be used above the head if you want to enhance the effect further.”
“It should be noted that the speaker should be instructed to avoid wearing dark clothes as this will be more difficult to light. Much like the way a greenscreen works, any areas of pure black will become invisible once projected onto the display screen. Although not as straightforward as a Skype or Zoom call, I’d expect the technology to one day find a way of miniaturising so that it becomes a more commonplace method of communication.
Another approach is Euclideon’s Arcade Table, which uses lasers to create the holograms. Users wear sunglasses that filter the light in a way that makes the holograms appear to float about 90cm off the table’s surface.
“The darker the space, the better the hologram,” Dell says. “Holograms are still projected, like your normal light-based projectors. The only difference is that we use lasers, but the same principles apply. If you project in a darker room, it will result in the picture having more clarity and being more attractive; whereas if you project in a lighter room, it will result in the picture appearing more faded.”
One unique aspect of Euclideon’s technology is that it uses artificial intelligence (AI) programming to speed up hologram development.
“We are the only game company in the world that does not have a single human programmer in our game division,” Dell says. “In the past year, we created 15 holographic arcade games with a team of just seven people.”
Artists and designers answer questions about what the finished product should look like, and the AI writes the code.
“We gathered information and explored many different games and simulations, and narrowed all the given information into roughly 270 simple questions,” Dell says. “People believe that there is a lot more than that, but there really isn’t.
“An example of such a question would be, ‘What happens if this object; touches another object with ‘type misc.?’ So if an object is given ‘type-bullet,’ and you have said, ‘dinosaur,’ if the dinosaur touches type-bullet what would happen? We found that our artists that had no programming experience whatsoever, had no trouble with answering these questions, and then figured that they had the ability to handle a project completely alone.”
As with many technologies, customers sometimes surprise vendors with use cases they didn’t expect being a good fit for holograms.
“When it comes to our business tables, we have had customers that have wanted to track certain things live, such as cars or aeroplanes flying in,” Dell says. “We didn’t overly anticipate that this was the one of the intended uses.
“Another surprise was food. It was a very interesting use case. Personally, it frustrates me when I visit a new restaurant, look at a menu and have no idea what the description entails or what the food looks like. It would be great if I could see my food before I order it. With the technology that we have, we are able to do this.”