Examples of Practical Application
1: Fraud and Security
Holograms are complex optical devices and difficult to make, which gives them an incredible advantage in the commercial security market. You probably have a security hologram in your pocket at the moment. 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 colour as you tilt your card up and down. It’s very easy to manufacture en masse – but also extremely difficult to forge.
Bank notes have also championed the use of secure holograms which started around 30 years ago. 1988 saw the first use of a hologram on a circulating note. They now appear on more than 300 denominations in 97 currencies. (Giesecks & Devrient 2017)
For our Canadian Dollar bills, take a look for the maple leaf window. It has a 2D holographic strip inside the clear border surrounding a frosted leaf. It turns out that leaf contains a hidden hologram of the denomination value.
2: Medical
Holography could also revolutionise medicine, as a tool for visualising patient data while training students and surgeons.
Many medical systems generate complex data using advanced imaging technology, such as Magnetic Resonance Imaging (MRI) and ultrasound scans. Normally, that electronic information is used to display a flat image on a computer screen, but it can also be used to produce full colour, computer-generated 3D holographic images.
Storing several different images in the same hologram means that the viewer can move around the display, allowing them to examine different organs or body parts. To date, the company has produced 3D holographic images of structures including the brain, liver, lungs, heart, skeleton, vascular system, nerves and muscles.
This may appear to be the stuff of science fiction but a commercial industry is now rapidly growing around these technologies.
3: Information Storage
We now generate huge amounts of data. Digital storage capacity increases (and becomes cheaper) every year and we have an insatiable desire to store our data and keep it for a lifetime. Just think about your own computer and the hundreds of gigabytes of information it can store, from family photos to videos and documents. A holographic image is stunningly realistic because the recording process stores all of the information about the light reflected from the recorded subject. That is a massive amount of information.
Holograms don’t have to record information about a visual object – they can also record pure data, pages and pages of it. This means that holograms can, potentially, store unthinkable amounts of information and offer long-term security, too.
4: Entertainment
If you’re a fan of music, then this is one hologram you are probably familiar with. It’s an old technology of illusion, but new designs have made it awesome. Various companies have found solutions to project photorealistic and flexible hologram technology for performance venues. It can be incredibly realistic too, as proven by the holograms of Michael Jackson or ABBA. Using high-end motion capture technology and full 3D CGI they completely recreate a person from head to toe, then projects them into a nearly invisible pane of glass.