What is a hologram?
The term hologram comes from ‘holos’, which in Greek means “everything”, and ‘grama’ which translates as “written message”. Holographic projection was pioneered in the 1940s by Hungarian physicist Dennis Gabor, who sought to improve the images from his laboratory’s electron microscopes. From then until now it has advanced to become a highly relevant element for some sectors such as audiovisual or security. For example, with holography of a person, the audience can feel that they are in front of a real person. In addition, the use of movement generated by the three-dimensionality, together with the use of sound, offers a greater sense of reality.
A hologram is a virtual image in three dimensions obtained through the use of light. This virtual image is generated by the interference generated by reference light rays and the light reflected by the object to be holographed on a sensitive base. Through the use of light reflection, the brain can visualise the object in its three-dimensional form.
How does a hologram work?
Holography or graphic vision is an advanced technique in optics, which uses light by means of laser devices to generate lifelike images.
The holographic image is first generated by recording or creating on a photographic plate what is to be represented, which can be an object or a person. Then by segmenting a laser beam into two separate beams, using a pyramid of mirrors in different positions. This produces a light reflection beam and an object beam directed at different angles.
The light beam is first formed outside the object that will establish the holography and finally on the final base or holographic plate. Also, as the light beams come together, the 3D images are designed. Thanks to innovations such as augmented reality, holograms have evolved and multiplied their fields of application, and have gone from being useful tools for certification and security, such as their use in bank cards, as they cannot be forged, to other more evolved applications ranging from healthcare to fashion.
What is a hologram for?
There are different types of holograms, mainly static or animated. Thanks to their versatility, they have gained importance in sectors such as the commercial sector thanks to the enormous visual impact they generate.
In other areas such as healthcare, they are also a useful tool, since thanks to 3D holograms, doctors can analyse and assess clinical diagnoses without putting patients at risk.
The same is true in the field of education, where these high-impact images help to capture the attention of students and enable them to learn more effectively about a wide range of subjects. Not forgetting the world of entertainment.
Implementing new technologies such as holography implies a competitive positioning, improves brand image and adds value. This technique increases user experience recall, an effective way to satisfy customers and increase revenue.
Moreover, its use is simple as 3D holograms do not necessarily depend on the use of augmented reality glasses and, even with the addition of other technologies such as artificial intelligence, it is possible to have much more developed experiences such as holographic telepresence. The latter even makes it possible, thanks to devices such as augmented reality glasses, to have remote meetings that seem real, even if each participant is thousands of kilometres away.
How to make a hologram?
To make a hologram, it is not necessary to be an expert in technology; thousands of amateurs manage to execute this optical illusion every day. However, some basic and elementary holographic materials are necessary, such as holographic film plates, laser pointer with red light, holographic processing kit and safety goggles.
First, the object to be holographed is chosen. It must be solid and shiny so that the light is captured correctly. For holography the room must be dark or dimly lit. It is also important to choose a solid and firm base on which to rest the object.
The laser pointer must then be placed on a strong surface and prevented from moving. The laser pointer should be placed at a distance of 30 to 60 cm from the object, it is important to adjust the red beam until it points directly at the object and illuminates as much as possible.
After positioning the pointer, it is time to capture the image by temporarily blocking the laser beam with another solid object, such as a book. The holographic film plate is then placed against this hard object, and the blockage is lifted 2.5 to 5 cm from the base for about 10 seconds. It is essential to move the frame slowly to avoid vibrations of the base or sudden noises caused by rubbing.
Finally, to achieve the optical illusion, mix the substances in the holographic processing kit and immerse the holography in the developing solution according to the time indicated in the kit. The process ends with the drying of the holographic plate and its exposure to direct light to inspect the holography in its entirety.
