What is Hologram Technology?

Holography, also known as hologram technology, is the next level of photography method that records the light dispersed from an item and then projects it as a three-dimensional (3D) object that can be seen without the use of any additional equipment. From transmission holograms through rainbow holograms to the most current 3D holograms, several types of holograms have emerged. The fascinating aspect of 3D holograms is that they enable presumably genuine objects or animations to appear to hover in mid-air or stand on a nearby surface. Furthermore, it is viewable from all sides, allowing a user to move around the display and construct a realistic-looking image.

Hologram Working?

A laser light beam is divided into two identical beams, one of which is aimed towards the object and subsequently scattered over the recording media (illumination beam or object beam). The other beam (reference beam) is diverted onto the recording media without passing through the object using mirrors. Photographic plates are a typical recording medium. At the recording medium, the two laser beams meet and interfere with each other. The photographic plates record this interference pattern.

Hologram 3D Reconstruction

There are three major steps involved in a 3D image reconstruction and the steps are as follows.

• Sequential recording from a different perspective or multi-view capture by a set of cameras
• The captured data is converted to a data format suitable for the display.
• Display of data from many SLMs to enlarge the viewing angle?

A 3D object reconstruction device and an aerial projection device are required for 3D hologram projection in mid-air. The reconstruction device generates a three-dimensional holographic picture. In addition, the aerial projection gadget creates a 3D hologram in mid-air.

Electro-holography is capable of projecting 3D pictures from the air without the necessity of many projectors or mechanical processing. To display a genuine 3D image, a rotating mirror system is also employed. A high-speed video projector is directed at spinning mirrors that reflect in all directions, allowing visuals to be seen in 3D from any angle. A monochromatic hologram is created by recording interference patterns with single-wavelength light. Multiple interference patterns are recorded with different wavelengths to create a colour hologram. Then, holographic projectors use lasers.

Applications of Hologram Technology?

• Data Storage: Using holographic data storage techniques a large amount of information can be stored inside high-density crystals or polymers. The advantage of this kind of data storage is to use the entire volume of the recording medium, not just its surface. Researchers believe that with the right type of polymers as a recording medium, gigabit per second writing speed and one terabit per second readout is also possible. Therefore, holographic storage has the potential to become the next generation of storage media.
• Security: Secure holograms are extremely difficult to forge because they are replicated from a master hologram. They are found on currencies, credit cards, passports, DVDs, and much other equipment.
• Medicine and Imaging: Hologram technology is on its way to revolutionizing medicine. It has the capability to produce a full-colour 3D hologram of the human body. Students and doctors can visualize the three-dimensional images of complex organs like the brain, heart, liver, lungs, nerves, and muscles. This technology can also help in surgical pre-planning. Before real surgery, the surgeon can fully visualise the entire?course?of the operation and thereby increase the chances of a successful outcome on patients. Digital holographic microscopy makes it possible to perform cell counting and analysis of subcellular motion deep in living tissue. It also supports simultaneous imaging at different depths.?
• Military: The 3D holographic maps of battle spaces is critical for military strategy. Secure military information can be stored using this technology.??
• Entertainment and Gaming: Holographic display can be used for creating live performance feel when the subjects are not physically present on the stage. Even, stars from the past can be resurrected to perform with modern artists live on the stage. Holographic display tables can allow real-time multiplayer gaming experience. Few manufacturers are integrating this technology with augmented reality and smartphone display, which can allow portable 3D gaming.??
• Education: Hologram technology can drastically improve the educational experience. It can provide interactive digital teaching in schools. This technology can even offer mixed reality by combining digital and real-world information. Students can examine and interact with holographic images to understand complex subjects. For example, they can visualize individual atomic particles and its behavior, or explore the ruins of ancient heritage monuments in a history class.?