All right, well, thank you very much. Good afternoon, everyone. I am Tracy Evans.
Welcome to the Holographic Tech Overview for 2024. Thank you all for coming. I've designed this talk to address two specific audiences. First, AR developers, VR designers, producers, technologists, or anyone looking to expand your creative toolkit or perhaps leverage your existing applications into new experiences for your clients.
The second, potential end users such as museums, architects, and business professionals who want to effectively implement these technologies in their environments. So first let me take a moment to tell you a little bit about myself and my company, Exhibitry. Our focus for more than 25 years has been on creating interactive experiences using cool cutting-edge technologies. Our projects range from corporate trade show activations to entire museums full of interactive experiences, utilizing holograms, projection mapping, theatrical effects, AR, VR, AI, and any other two-letter acronyms we can think of. I like to say that we are storytellers by trade and technology geeks by heart.
We have actually four locations. Two of them are in the digital production studio, and the fabrication facility are in Houston, Texas. We also have a branch office in Philadelphia.
and a secondary fabrication shop outside of London, Ontario. And I mention all that to point out that over the years, we've utilized almost all of these techniques and technologies in our own projects, and even invented a few along the way. The purpose of my talk today is to demystify the wide array of available holographic technologies, information on which can be often confusing, if not entirely opaque. I want to provide you with some practical insights on how to apply each technology effectively to suit your specific applications and environments. But let's start at the very beginning, if I may, with a brief history of holograms.
For many people, the mention of hologram might conjure up a mental image like this. 1977, Star Wars sets the standard for the depiction of holograms in popular culture. A fuzzy digital doppelganger floating in mid-air. Of course, it's viewable from 360 degrees. It's floating in the middle of the room with no visible means of support or medium.
And, of course, it's projected by an astro-droid. The reality of holograms is a bit different. But most of them do have some relation to science fiction movies in that they're all some form or another of illusion. Just as an aside here, the subject of illusion is one that I do know well from personal experience, having spent the decade of the 1980s as a professional stage magician.
Oh, thank you. I brought along my baby pictures here to show you. But I digress.
The first holograms date back further than my magic career, back to the classic magician stage illusions of the 1800s. Imagine a dimly lit Victorian theater. A conjurer named John Henry Pepper enters from stage right.
Soon, a ghostly apparition appears on the stage, floating in midair, translucent and hauntingly real. It's much like the Princess Leia scene we just saw, but this is a live stage illusion that came to be known as Pepper's Ghost. A gas-driven theatrical light and a large sheet of glass were used to illuminate and reflect an actor below the stage. making them appear as though they were floating in the middle of the stage, without any visible means of support or medium, and no droids required.
Interestingly, 200 years later, many forms of this stage illusion are still used in hologram techniques. Moving right along, in 1947, Dennis Gabor, a Hungarian physicist, developed the theory of scientific holography, as well as coined the term hologram. He discovered that using a laser one could record light waves and reconstruct them into a three-dimensional image. Unfortunately lasers wouldn't be available widely for another 20 years, but shortly after that his discovery earned him the 1971 Nobel Prize in Physics for the invention of holography. Now science is all well and good, but not to stray too far from the theatrical origins of holograms.
Here is Salvador Dali in 1973 using a laser-based technique to create a 3D hologram of Alice Cooper's brain, like you do. Right? Which brings us to present day, and that concludes our brief history of holograms, where today even the latest techniques still rely on a blend of current technology and age-old conjuring psychology.
But let's briefly touch on what isn't a hologram, such as transparent video screens or pixel mesh window displays. While these are impressive technology, they don't really fall into the category of hologram that we're talking about. For example, consider this window display, this retail window display. This setup employs a transparent film.
When applied to the inside of the glass, it could catch a video projection. From a distance or on YouTube, it appears that a holographic image is floating inside the showroom. This illusion is broken, however, when seen with your own eyes.
your two eyes, instead of the monoscopic lens or single eye of a camera. Thus, this is not what I would consider to be a hologram, at least in the way we'll be defining it for this presentation. Now, that's not to say that video projectors equal bad holograms. We will see some examples in a moment of some very well-produced projected holograms.
From those, what you won't see is this. Notice the light on the ground here. This is called projector spill. This occurs when the light from the projector spreads beyond the intended display surface. Now the best projected holograms take this into account and go to great lengths to hide the spill so as not to give away the secret revealing the method of the magic trick.
Next is the subject of transparent screens. LG just introduced a new line of these to the consumer market at CES this year. To their credit, they did not go anywhere near calling them holograms, but there are some companies that go straight to that direction. Another technology advancing quickly is LED mesh window film. Again, this can create a super impressive visual effect, painting these semi-transparent walls with live video.
But there are some companies that might market this as a holographic room. Personally, I feel that's a dishonest term. Even though holograms we're discussing today are all optical illusions, there's a line to be drawn between using illusion to create an effect and using illusion to market a product.
Sadly, there are charlatans in the industry who craft marketing materials to imply certain qualities that might strain credibility or... completely misrepresent a product's capabilities. That's one of the purposes of the talk today, is to equip you with the knowledge to understand the facts and be able to distinguish them from the fiction.
Anyway, back to what we're defining today as a hologram. They are indeed digital magic tricks, the goal of which are to present floating imagery, create visuals with no apparent physical medium or display, imply volume or depth, and maintain their illusion by not revealing their method. And while they may not be holograms in the strictest scientific sense, they do a fantastic job of wowing audiences and creating immersive experiences.
So, our time together is both precious and brief, so I'll focus on some of the most practical and readily available technologies. Each of these has their own strengths and weaknesses, and this brings us to the core of today's presentation. I'll review each and rate each technology based on this criteria. Obviously, this is all subjective opinion and your mileage may vary, but my goal for you is to understand each approach, know when and where to best deploy each, so that you can make informed decisions and tailored for your project needs. So, with that, let's start with projection.
The art of using a video projector in place of Pepper's gas-lit subjects. There are... Two popular techniques for stage holograms, variations of Pepper's Ghost, are still done occasionally when one is fortunate enough to find themselves with access to a proscenium-arched theater and a full stage crew.
But a more practical method is one that can be done in open air, in the open air of a hotel ballroom or a special trade show theater that we'll look at. This technique projects video directly onto the back of a special fabric. which is a virtually invisible curtain of fine mesh infused with metallic threads.
In either technique, the subject is filmed or is animated over a simple black background. Projected, the mesh remains invisible in the black areas of the video image. The metallic fibers of the mesh capture the light that is emitted from the projector and to some degree they bend it around those fibers, causing the imagery to appear on the front of the fabric as an animated floating visual.
Projection theater, a little portable theater here, is a good example of a successful illusion. It's designed to hide the projector so the audience doesn't see the beam of light or the source from which it's projected. It's also designed to capture the projector spill, in this case in the upper area of the canopy, where a series of baffleds hides it from the audience, completing the illusion.
So let's look at projectors. Projection holograms is a score. The illusion factor can be very high when the projector and the spill are well hidden. Implications of depth are aided by the distance to the audience as well as careful design of the content. Resolution is typically low for this large of an area, but again, the distance to the viewer makes up for the deficiencies there.
For image size, projection takes first prize, really. And video projection allows for interactivity because it's a live video input. Stage projections lend themselves well to remote telepresence, so someone at a remote location can beam in on the stage and interact with the stage presenter, or even with the audience using a two-way internet streaming connection, for example. Moving on.
Augmented reality. AR is arguably a hologram, kind of, sort of. It can certainly create a very convincing visual experience.
But it's less magical than most of the others we're talking about because it's hard to suspend disbelief when you're holding a phone or donning a headset. Nonetheless, for completeness, I wanted to include HoloLens, Meta, and Apple Vision Pro in here and give them a score related to this as well. While difficult to correlate with the other scores, here they are. AR headsets create a very convincing holographic illusion, but arguably don't satisfy the illusion aspect as previously defined. 3D depth is perfect, being able to deliver a true stereo image.
Resolution for consumer headsets has just reached the point where they've eliminated the screen door effect of seeing between the pixels, so that's great. Image size is... Great, because it's as big as you can see.
It's life-size, but the field of view is obviously a current limitation. And interactivity is designed in from the ground up. Next, transparent displays. I mentioned these earlier, but let's take a look at some actual examples.
Transparent display boxes, such as HoloBox or the Hype Box. I love that product name, the Hype Box. They excel at combining physical products with an... overlay of digital content.
It creates a really nice AR type experience. Ideal applications for these are retail product displays or museum exhibits that feature an artifact or a product in addition to the digital content. But in my opinion, these devices don't provide a very strong holographic effect as we've previously defined it.
The illusion of depth looks good in photos and video but in person, the illusion is less convincing due to human stereo vision and parallax. Any lateral movement or even just standing too close reveals the image is actually attached to and displayed by the front glass of the surface. These do, however, score high points for size, high-resolution imagery, telepresence, and real-time interactivity.
For example, this is a museum exhibit that transforms from a video wall into an interactive topographic map as the physical map within the enclosure is revealed as the screens turn transparent. So, quick score for transparent displays. The holographic illusion is, shall we say, modest when seen in person, as is the depth when seen live, unless it's viewed from a distance.
From a distance, and by limiting the field of view to avoid the parallax, The illusions can look very convincing. Resolution is great for most needs. Size is not an issue due to the variety of sizes available. Interactivity is available with touchscreens or a variety of other input devices.
And remote telepresence on some is a very nice feature as well. Next, moving right along, let's look at a few reflective holograms. This design calls back to Pepper's Ghost technique.
They basically work in the same way that a video teleprompter works, in that it's a see-through transparent piece of glass that reflects a video display positioned at a 45-degree angle to the glass. And the glass pyramid is a classic example of a reflective hologram. The depth illusion here is really enhanced when a physical object, a physical product here in this case, is placed inside that pyramid.
This is a retail display. A small Bluetooth speaker is tortured again and again with animated fire and digital water. The animated content precisely lines up with the object, and thanks to the Pepper's Ghost principle, there are no parallax issues like we saw with transparent screens. It's a very convincing illusion.
But as impressive as it looks, sadly, it will rate low on my illusion scale because even the most casual examination of the device reveals its method. A mere glance upward and one sees the video monitor that's displaying the imagery that's reflected in the pyramid. This is analogous to projector spill in that it kind of gives away the trick.
So, for glass pyramids, my scores here, the holographic illusion is very strong, but at a limited viewing angle. Since it so easily reveals its method, it lowers the marks in that category. Depth is enhanced by interacting with a physical object. Dimensionality for the pyramid is super high in that you could have different views of the hologram from different sides of the pyramid. This is a feature unique to this and one other that we'll look at in a moment.
Image resolution is adequate for the size, but the size itself, the size of the image in relation to the pyramid can be a little limiting. And while interactivity is certainly possible, this is a real-time device, but it's also a very useful tool for the use of the pyramid. It's seldom seen in this format, and I'm really not sure why it would really lend itself to it. This holographic table, however, is kind of a modern improvement on the classic glass pyramid technique.
It uses a 45-degree reflection, just like the pyramid. It has two sides, so viewers can walk to the other side of the exhibit and either see the back of the hologram or entirely different content. But the design of this enhances the illusion aspect over the pyramid by hiding the method and hiding the medium. The glass edges are invisible.
They're not seen here. So the chamber appears to be just this empty canopy. The video monitors that produce this image are hidden in the table just above the eyeline of the average viewer. So let's look at the scores here.
The illusion factor here is very high. Because the method, the glass reflection, is properly hidden, and the image display is well concealed. Depth is good with thoughtfully produced content, which we'll talk about in a moment as well.
Resolution is great for the size and distance. The size of this hologram is good. The ratio of image size to unit size is fairly well balanced. And again, it's a real-time display, so interactivity is virtually unlimited.
Now, let's talk about LED fans. These devices use high-speed spinning blades embedded with LEDs to create the illusion of a floating image. The blades spin so fast that they become invisible to the eye. The rapidly color-changing LEDs work like the pixels on a video monitor. And human persistence of vision then mushes the whole thing together in your brain.
into a continuous and relatively solid image. Let's check the scores on LED fans. The illusion of the floating image is very strong, but the visibility of the motors and the audible whirring of the blades, that can detract from the magic of the effect.
It's an audible tell for someone standing close to it. So LED fans work best when they are some distance from the audience. Depth is achieved well through thoughtful content design.
While the image is still a flat plane, just like all holograms, the content shown here in particular is a great example of how to imply dimension using forced perspective, 3D animation effects, transparency, and motion. Resolution for LED fans is adequate from a distance and relatively close. Size... Size is a great advantage here.
Size is virtually unlimited because LED fans can be assembled modularly like a video wall. So there's practically no limit to the size of image you can get. Interactivity scores high thanks to recently available real-time display capabilities. So these are wonderful devices. I do have to note there is one important drawback to LED fans, and that is they are somewhat camera shy.
The persistence of vision trick works well for our relatively slow human eye, but not so much for cameras. Many photos end up looking like this. And this can be detrimental in that holograms are a selfie magnet. So be prepared for your customers'snapshots to look incomplete, less magical and ultimately disappointing to Instagram influencers. Unless one knows how to control the shutter speed on your camera and adjust that, which I'm sure we all do right before we take a selfie, right?
The next category is direct... view. And this is a unique category.
Unlike projection or reflectives, here we're looking directly at a high-resolution display. One of these technologies hides the display to create the illusion of a floating life-size hologram, while the other prominently features the display device, making it clear that you're viewing a sophisticated 3D display. But let's start with Just a moment, please. Let's start with HoloTube.
It's a unique piece among holographic technologies in that it doesn't rely on reflected video, spinning LEDs, projectors, transparent displays, or any of the other techniques typically used in holograms for it to create its real-time illusion. The viewer is actually looking directly at a 4K display in all its glory. But a series of materials and filters hide that monitor so that only the desired image is seen floating in the center of the tube. Let's review the Holotube scores.
The illusion factor is high. The method is well hidden in that it stands up to careful examination. You can view it from all angles.
You can even put your nose right up on the acrylic and not find any revealing visual tells. The depth illusion is good, thanks to the parallax created between the floating image in the center of the tube and the tube background. The live interactive 3D environment also helps. Interactivity is built in.
This is a cool interactive 3D exploration of Kennedy Space Center through 10 decades of iteration. The image resolution is high, even for close-up viewing. And as for size, the technology scales to just about any size. This one's about 12 feet tall, I think.
And then the looking glass spatial display is another direct view technology, perhaps more accurately described as a glasses-free 3D display. The illusion of depth is exceptionally strong. It uses a sophisticated lenticular display to deliver...
up to a hundred images simultaneously, each from a different angle. The filtering separates the imagery pairs for each eye, and as you move laterally, the filters deliver the image pair from that angle, offering about a 60-degree field of view. It's also a super fun device in that it comes with software that lets you take spatial pictures with the most current phones.
and wirelessly send them to the display, similar to the capabilities of the Apple Vision Pro headset. Checking the scores here, the illusion factor is very good, but a little mixed, because the display surface is not hidden. The experience is more of a 3D screen than necessarily a floating hologram. But the depth illusion is outstanding, and currently very mysterious. Very mysterious to audiences or as Arthur C. Clarke might have said indistinguishable from magic.
The illusion resolution is very good. The size is good and that like Holotube the technology scales in this case up to I think there's a 65 inch unit and interaction is quite possible although it does require probably require a pretty powerful computer to real-time render. 100 images simultaneously. Oh, and with that, at 25 minutes exactly, I will conclude my tech overview for 2024. I hope you found this insightful, perhaps inspiring.
If you have any questions you would like to discuss further, feel free to reach out to me after the session. And for that, thank you very much.