The first fundamental step to discover the meaning of the term “hologram” is to know its etymological origin. In this case, it should be noted that it is the result of the sum of the components of the Greek lexicon.

• The noun “holos”, which can be translated as “everything”.
• The word “grass” is synonymous with “written message” and “plotted message.”

A Nobel invention that arises from a failure

Likewise, it is of great interest to know who was in charge of coining the term was none other than the Hungarian physicist Denis Gabor (1900-1979). It basically gave it a theoretical shape in 1948. Although, it had to wait until the 1960s in order to be able to demonstrate the existence of the hologram in a practical way.

The complex method that garbor designed has two steps: the first consists of fixing the image of an object on a photographic plate in a specific way and, the second, in illuminating said plate once it has been developed. He did not get the success he wanted with his work, the purpose of which was to improve electron microscope images. However, from that small failure came his great success: a new way of representing reality.

In 1948 he carried out what would become his first hologram with the light emitted by a mercury lamp. The object was a small round slide , almost a millimeter and a half in diameter, containing the names of the physicists Young, Huygens, and Fresnel. That first experiment was very rudimentary, but it laid the foundation for holography. In 1917, Dennis Garbor was awarded the Nobel Prize in Physics for the discovery and development of the holographic method.

Characteristics

A hologram is characterized by being an image obtained from holography. It is called holography, the technique that, using laser lighting, manages to generate colorful images in three dimensions.

This means that a hologram is a three-dimensional image that is generated by using a laser. This allows the microscopic recording of a photosensitive film: at the moment in which between two light beams an interference is produced, the light of one of the beams can be reflected on the object. Said light, when capturing another from a certain perspective, reflects the three-dimensional image.

With proper lighting and processing, the 3D image can be projected beyond its limits , allowing the viewer to see it seamlessly and changing the perspective with respect to its position.

Technical details aside, in colloquial language a hologram can be considered to be a specially produced laser image that is recorded on a sensitive film with the ability to produce objects in relief . For this reason the three-dimensional image seems to be suspended in space and can be observed from different perspectives.

An observer, before a hologram, gives the impression of being in front of a real (physical) element. This results in the holograms being realistic experiences, for example in concert.

Hologram example

A clear example of this was an appearance by Michael Jackson in 2014 , at the billboard awards ceremony using a hologram. In this way Jackson, who died 5 years earlier, performed live in front of a group of dancers.

It should be noted that the hologram has become a very important element in the tourism field . Thus, we can see that it is used to give prominence to certain monuments and the presence of characters who have already died or events in the past.

A clear example of this is the Stirling Castle located in Scotland. In this fortress, which has existed since the 15th century, you can learn about the history of the city and access the interior of it, a hologram is present, practically, which comes to represent one of the most important figures of the past of the place : the hero of the region William Wallace (1270-1305). This figure is resurrected thanks to the hologram with the purpose of welcoming visitors.