A hologram can simply be defined as a 3D (three-dimensional) image. It is usually produced in a 2D (two-dimensional) surface but it gives a 3D image of a certain real object. Therefore, users of the hologram do not need to have special equipment in order to view the image in 3D.
Most of the holograms produce very precise images that look exactly as the real object because the image is in 3D just like the object is. To expound on this, if one views a hologram from different angles, the image will appear differently, unlike a 2D image.
The hologram therefore tends to behave like a real image because a real object viewed from different angles will appear different to the viewer at each of the angles. Some even appear to be in motion as the viewer changes the viewing angle or walks past them.
Some of the holograms give views of different objects if the viewer changes the viewing angle. They may even change their color as the viewer changes the viewing angle (Wilson 1).
Holograms have other traits that may be quite interesting. If one cuts the hologram into a half. Each of the two halves has the entire image that was initially in the whole hologram.
The same will also be the case if the hologram is split into four pieces; even a very small piece of the hologram will have the image of the original hologram. This, together with the fact that a hologram can contain various different images on the same surface has puzzled many people who do not know how holograms work.
In addition to the aforementioned surprising characteristics of holograms, a holographic image of a magnifying glass will be able to act as a magnifier itself, just like the real object (Wilson 1).
Given the details that a hologram carries, it is obviously much harder to make one than it is to produce a 2D image. However, despite this difficulty in making holograms, they are almost everywhere; in some credit cards, identity cards, and even in some driver’s licenses (ACEPTGroup 1).
The main reason why holograms are popular is because it is very difficult to copy a hologram and thus they are used to secure cards, documents and other products. Thus if a credit card has a hologram on it, it is difficult for it to be forged.
How to make a hologram
To make a hologram the following items are required:
- A laser – this is used to magnify the light that is used to produce the image. Depending on the laser that one chooses to use, he/she may need to have a shutter for controlling the exposure of the object to the laser light.
- Lenses – these are used to spread light in order to shed it on the whole image while regulating its intensity.
- Mirrors – these are used for directing light to the right locations on the object.
- Holographic film – this is used to record the light. Its use is mainly based on the fact that it has a very high resolution that helps in creating high-quality holographic images (Wilson 2).
There are a number of ways in which one can arrange the above listed items to make a hologram. The following is the set-up for the basic hologram.
- The laser is directed to the beam splitter that separates the light into two beams.
- Mirrors are used to direct the beams from the beam splitter to their intended targets.
- One beam is reflected from the object to the holographic film
- The other beam is directed to the holographic film after reflecting off the mirror only (ACEPTGroup 1).
While the image is being produced, it is advisable to have the set up in a poorly lit room because the image will be of higher quality in a dark room than a lighted one. The surface of the set-up is supposed to be level enough to keep the equipment still.
This is because any vibrations due to passing vehicles or even the movements of the person making the hologram may affect the quality of the image (Wilson 3).
Uses of holograms
Holographic images and products have been widely used in the commercial world to give products authenticity and make them acceptable to customers. Due to the fact that it is almost impossible to produce a counterfeit of a product that carries a holographic product, holograms have been used widely in applications for security (ACEPTGroup 1).
In addition to these, holograms provide a means of attractive packaging of products, and thus they can be used in when one needs to give fancy gifts. They have also been applied in art by helping artists to produce 3D pieces of art.
Another area where holography has been applied is in quality control as well as component testing in industries. This is due to the fact that it is possible to make holographic images of an object on the same surface before and after subjection to stress. Thus the quality of the change in the object due to the stress can be easily observed.
They can also be used to display valuable artifacts. In this, an image of the artifact is made and displayed instead of the actual object due to security reasons. This is especially necessary if the people viewing the artifacts cannot be trusted.
E.g. when a certain artifact is moved from the museum to various destinations to be viewed, it may be necessary to make a hologram of the artifact instead of using the artifact itself (Wilson).
Some of the most remarkable areas where holograms have been applied include credit cards (ACEPTGroup 1), ID badges, currencies, passports, registration of automobiles, driver’s license, stock certificate, government documents, branded products, liquor etc. In these products, holograms give the customer the assurance of authenticity and/or security.
Disadvantages of holograms
Although the use of holograms for commercial purposes is certainly a good idea, the use of holograms has several disadvantages. First of all, players in the field of holography are very few. This means that the people who use holographic images are few, and similarly, companies specializing in holography are also few.
This is the case due to the high cost that is involved in the production and use of holographic images. The high cost is also a disadvantage on its own.
Holography is however expected to gain popularity with time as people increasingly need to secure their products and as better technology brings the cost of producing holograms down.
Another disadvantage is that holograms that are meant to prevent documents and products from being forged are normally unimpressive. They change their shapes and colors as the viewer moves back and forth. To the viewer, they appear as smears of color or sparkly pictures (Wilson 1).
From the discussion above, it is clear that holograms are relatively common. This is because virtually every adult has a product carrying a hologram in his wallet or her purse. Holograms have particularly been useful to players in the financial sector due to their ability to secure credit cards.
This is because financial products and transactions need to be as secure as possible. They have also been useful in other areas that require tamper-proof documents like the ID cards, driver’s license and government documents.
This is due to their effectiveness in securing documents which can be explained by the fact that it is difficult to forge a holographic image.
The process of making a hologram depends on the quality of the holographic image required.
If an image of great quality is required, the equipment for making the hologram must be carefully set up in a stable surface, and in a room whose air has been closely monitored in order to ensure that there will be minimal vibration as the production of the hologram goes on.
Holography specialists may even choose to use more sophisticated equipment or use basic equipments of high quality in order to achieve better results.
Holography has some shortcomings that stem out of the fact that it is expensive, time consuming, and it is not very popular. Holographic images produced for the purpose of security may not be very appealing to their viewer or user.
Despite these disadvantages, holograms have been useful in a number of ways, which have been listed in the discussion above.
ACEPT Group. Holograms. 2000. Web.
Wilson, Tracy. How Holograms Work. 2007. Web.<https://science.howstuffworks.com/hologram1.htm>