Holography is a photographic technique that records the light scattered from an object, and then presents it in a way that appears three-dimensional. Holograms pop up in movies such as “Star Wars” and “Iron Man,” but the technology has not quite caught up to movie magic — yet.
Various types of holograms have been made over the years, including transmission holograms, which allow light to be shined through them and the image to be viewed from the side; and rainbow holograms, which are used for security purposes — on credit cards and driver’s licenses, for example.
How holography works
To create a hologram, you need an object (or person) that you want to record; a laser beam to be shined upon the object and the recording medium; a recording medium with the proper materials needed to help clarify the image; and a clear environment to enable the light beams to intersect.
A laser beam is split into two identical beams and redirected by the use of mirrors. One of the split beams, the illumination beam or object beam, is directed at the object. Some of the light is reflected off the object onto the recording medium.
The second beam, known as the reference beam, is directed onto the recording medium. This way, it doesn’t conflict with any imagery that comes from the object beam, and coordinates with it to create a more precise image in the hologram location.
The two beams intersect and interfere with each other. The interference pattern is what is imprinted on the recording medium to recreate a virtual image for our eyes to see.
The recording medium, where the lights converge, can be made up of various materials. One of the most common used with hologram creation is photographic film, with an added amount of light-reactive grains. This enables the resolution to be higher for the two beams, making the image look much more realistic than using the silver halide material from the 1960s.
History of holography
The development of hologram technology started in 1962, when Yuri Denisyuk, in the Soviet Union, and Emmett Leith and Juris Upatnieks at the University of Michigan developed laser technology that recorded 3D objects. Silver halide photographic emulsions were used for the recording medium, though the clarity of said objects wasn’t perfect at the time. But new methods involving the conversion of transmission with the refractive index allowed holograms to be improved over time.
Future of holography
For now, holograms are static. Recent presentations, such as CNN’s special effect of a reporter appearing live from another location, and the late Tupac Shakur “appearing live” at a music festival, are not “true” holograms.
However, new holographic technology is being developed that projects 3D images from another location in real time. The images are also static, but they are refreshed every two seconds, creating a strobe-like effect of movement. The researchers hope to improve the technology over the next few years to bring higher resolution and faster image streaming.
And in March 2013, it was announced that a group of researchers from Hewlett Packard Laboratories has developed glasses-free, multi-perspective, 3D display technology for mobile devices.
How does the workflow look when developing a 3D hologram?
The creation of a 3D hologram consists of four steps:
1. The idea:
Everything starts with a good briefing to give the team an idea of which product, service, or process will be presented, what the message is, what the USPs are, and where the 3D hologram is going to be used. The briefing is the basis for developing an initial idea about how the hologram could look, which effects reinforce the eyecatcher effect, which hologram projector best suits the product and where it is going to be used. All of these points are then discussed with the customer, to make sure that all of the customer’s wishes have been taken into account before the storyboard is created.
2. The storyboard:
The storyboard describes and visualizes the key scenes and content of the 3D hologram. Once it has been approved by the customer, the 3D designers, motion designers, and sound artists get to work.
3. The design:
3D models are set up, or delivered CAD data are imported and then photorealistically textured and displayed in the right light by the 3D designer. With the help of effective 3D programming, additional effects and the right music as well as a great deal of computer capacity now help bring the animation to life. The motion designers implement the basic idea visually and the sound artists underlay the hologram with sound and a diversity of sound effects in order to create a multi-sensual effect.
4. The finish:
The magic of the animation becomes perfect when a real object serves as a reference inside the system. This can be a product, some 3D lettering, or a seemingly simple base. This is how an illusion with a WOW effect is created that is a delight to all who see it. The 3D hologram is tested live on the hologram projector selected by the particular customer, with the aim of guaranteeing high quality and achieving an optimal result. Depending on the hologram projector selected, it can be set up by the customer, the stand constructor, or by a special technical team in the case of a large-scale hologram projector.
Holograms in the Future
The general public is fascinated by holograms. However, holograms are major business. It is suggested that by 2020 the market for genuine, display holograms will be worth $5.5 billion . Here are some of the incredible ways holograms are currently used.
Geographic intelligence is critical to military strategy. Fully dimensional holographic images are being used for improved reconnaissance. These 3D holographic maps of “battle-spaces” allow soldiers to view three-dimensional terrain, look “around” corners, and train for missions.
The company takes computerized image data and turns it into a holographic sheet. “Not only can users ‘look into’ the high-quality 3D image of the terrain stored in the hologram sheet, but the technology is simple to use and can be rolled up for easy storage and transportation.” The maps are also useful in disaster evacuation and military rescue scenarios.
Society generates incalculable amounts of data every day. Digital storage capacity increases every year. Our personal computers store hundreds of gigabytes of information, including family photos, videos and documents. Now think about a storage disc being corrupted. The losses are unimaginable.
Though holograms create fascinating imagery, they don’t just have to record and present a visual object. Holograms are capable of recording pure data – mountains of it. Holograms have the potential to store absurd amounts of information. The current prototype systems store 4.4m individual pages of information on a DVD like disc. They also offer a unique form of long-term security.
“If you make an optical hologram of a page of information and then smash it, for example, you can reconstruct it from any of the pieces. This makes holographic data storage extremely reliable. Unlike CDs and DVDs, which store their data on the disc’s surface, holograms store data in three dimensions and those pages can overlap in the storage space.”
Holography is on its way to revolutionizing medicine. It can be a tool for visualizing patient data in training students and surgeons.
Current systems like Magnetic Resonance Imaging (MRI) and ultrasound scans generate complex data using advanced imaging technology. This technology has the capability to produce full color, computer-generated 3D holograms.
Using these 3D images for training and display, holograms require no viewing devices or glasses. Students and doctors can simply “look”, unhindered, at the three-dimensional images. These images can include the incredibly complex organs and systems of the body, like the brain, heart, liver, lungs, nerves, and muscles.
Fraud and Security
Because Holograms are complex and hard to make, this makes them an incredible advantage in commercial security.
If you have a credit card, you have a hologram. “That small silver rectangle of a dove on your credit card is a white-light, mirror-backed, transmission hologram. It displays a three-dimensional image which is visible as you move from side to side, and changes color as you tilt your card up and down.” These holograms are incredibly difficult to forge.
Bank notes are also starting to incorporate secure holograms. In the UK, the newest £5 bank note has an image of Big Ben and uses holography to produce a set of changing colors as you tilt the note. There is also a 3D image of the coronation crown “floating” above the note when tilted.
Artists began experimenting with holography the moment it became a practical process. There are artists around the globe using the three-dimensional of holograms to bend and cut space, combine collections of still images or video to produce animated 3D works, and to sculpt pure light.
Most recently, an exhibition in central London presented a show of creative holography. International groups of selected artists contributed work to an exhibition on Governors Island, New York, and artists from Canada, Italy, the US and UK were chosen for an exhibition using holography and the media arts in Santa Fe, New Mexico this summer.