Hologram Overview

• Full transfer tamper evident hologram:
  In this type of hologram, the labels or seals once fixed at the desired place, it is not possible to remove them. Any attempt to remove the hologram or tamper with it results in only the top layer of the film to be separated from the holographic image. What is left is just a clear film, while the holographic image stays where the hologram was originally affixed. This type of hologram is available in various colors.
  
• Partial Transfer tamper evident hologram:
  In such type of hologram, any attempt to tamper with it or remove it results in the holographic image breaking up. Partly the film is removed or partly the substrate on which the hologram was affixed breaks up. Any further attempts to still remove the hologram image intact will result in completely destroying the hologram. Partial transfer tamper evident holograms generally carry a checkerboard or circular pattern.
  
• Transparent holograms:
  Transparent holograms as the name suggests are see through holograms. They can be fixed over a number, text or a photograph to make sure that they can be clearly visible. Any attempt to tamper with the hologram will result in the complete or partial destruction of the hologram.
  
• Translucent holograms:
  They are also see through holograms. While transparent holograms merge with the substrate on which they are fixed , translucent holograms stand out and are easily noticeable. They can be partial transfer or full transfer.

Security Hologram
Security holograms are the most common type of holograms used in many industries. Security hologram products like stickers, labels, cards are found on a host of products and packaging, which include compact discs, cosmetics, computer software, watches, sporting goods, hang tags, certificates, tickets , passes and many kinds of identification and membership cards. The most common example of a security hologram is one on every VISA® and MASTER CARD® produced for the past 12-15 years. In various countries like Austria, Bulgaria, Finland, Kuwait, Switzerland, and Russia, security hologram is seen on federal currency and passports. In the United States, it is common to find high security holograms on driver's licenses as well as on postage stamps and on a variety of government issued bonds and certificates.

Types of security hologram products

The various types of security holograms are as follows:

Tamper Evident Holograms

Hologram Labels

Hologram Stickers

Hologram Hot stamping Foil

Hologram Tape/Security Tape

Hologram Seal/Security seal

Hologram Badge

Tamper Evident Seal

Transparent Holograms

Hologram Tag

Why security holograms work?

Security holograms are rapidly becoming an essential method of protection against counterfeiting. All holograms belong to a class of images known as Diffractive Optical Variable Image Device (DOVID) which is expensive, a specialized and technologically advanced equipment. Security holograms or for that matter any other hologram products cannot be copied by standard printing techniques or replicated by color copiers or computer scanning equipment. Usually, counterfeiters select the path of least resistance, and as such facing a security hologram will frequently cause them to give up their efforts to copy your product and move on to easier targets. As a result, the use of security holograms virtually guarantees product authenticity.
Advantages of security holograms

The basic advantages of security holograms are as follows:

• They provide security.
• They provide authentication.
• They provide protection against counterfeit.
• They cannot be copied.

Property of rainbow hologram
An important property of rainbow hologram is that perspective information is lost in one axis. That means you may not be able to see a change in perspective when looking from above or below.

Recording process of rainbow holograms
Rainbow holograms are made by a double holographic process. Here an ordinary hologram or a transmission hologram is used as the object. The second hologram is made through a slit. This is a horizontal slit which limits the vertical perspective of the first image and there is no vertical parallax in the resultant rainbow hologram. During image reconstruction, the horizontal slit operates. It removes or eliminates the coherence requirement on the viewing light. This makes it easy to attain the three-dimensional character of an image while the viewer moves horizontally. The brightness of the image is also maintained. If the viewers eye is moved vertically, no parallax is seen and the image color moves through the rainbow spectrum from blue to red. It is seen that when a rainbow hologram is viewed at an average height, the image appears yellow-green. On a little higher height , the color changes from orange or red and if we dip, it becomes blue or violet. Thus, it is referred as rainbow.

Advantages of rainbow hologram

The tamper evident hologram labels usually have a "dots" release pattern or words VOID, OPENED, etc. showing tampering. Under normal circumstances, the release pattern will appear when the label is removed after the label has been applied. However, there are certain conditions under which the tamper evident feature can be inadvertently activated during the process of affixing the label. We give below few tips to minimize pre-triggering of the tamper evident feature in labels:

Tip 1. Minimize pressure and contact with the adhesive side of the label. Manually remove the label using light pressure and transfer to your finger. Then, apply the label immediately to the intended surface. The tamper evident feature gets activated the label is positioned on your fingers for long time or if the adhesive side is handled with too much pressure.

Tip 2. When handling the labels, use skin moisturizer to the tips of fingers which will touch the adhesive side of the label. This will minimize the chance of activating the tamper evident feature during application. Otherwise use a rubber finger tip on the finger which is to touch the adhesive label.

Tip 3: Flag the label. In other words, peel back a portion of the liner to expose a small portion of the adhesive side of the label. You now affix the exposed portion of the adhesive to the intended surface. Next peel away the balance of the liner to fully affix the label.

Tip 4: Never use a metal or plastic instrument to affix the label. The hard and dry surface cause the tamper evident release to activate.

 

Promotional holograms/3D Lenticular are used for

• For advertising and sales.
• For brand promotion
• As give-away in trade fairs.
• Used on magazine, books, brochure cover, greeting cards etc.
• Used as mementos, keepsakes or tokens.
• Several 3-dimensional multicolored images of deities, places of worship, monuments, palaces, structures, buildings of historical or archaeological importance.
• Full-color holograms can be considered as exquisite exhibition pieces and presentation plaques.

Multiplex Hologram

Multiplex holograms are used very widely today in various applications. The multiplex hologram is a popular type of hologram depicting the holographic storage of photographic information. It is a type of hologram which is produced by combining a large number of photographs in a holographic manner.

We all know that a hologram usually provides a way to record and reproduce a three-dimensional, still image of an object. The method of recording and replaying a three-dimensional, moving picture is called a multiplex hologram. In multiplex hologram, a three-dimensional image is viewed in a slowly turning transparent cylinder. In other words, multiplex holograms represent large number of flat pictures of an object which is viewed from different angles. These pictures are then combined into a single, 3D image of the subject. In case of a rainbow hologram, the same image of the object appears in a different color when viewed from different angles.

Property of multiplex hologram
Multiplex holograms are an interesting type of hologram. Some important properties of these holograms are as follows:

• Multiplex holograms not only represent a three-dimensional image but also have the possibility of capturing movements.
  
  
• Usually a multiplex hologram creates horizontal parallax and not vertical parallax. This is because the camera usually moves around and does not usually pass over the subject. The subject moves around in front of the camera.

Stages of production of multiplex hologram

Information reference source from http://www.holo.com/holo//book/book5.html

• First stage: A group of photographs of the object is taken. The number of photographs taken depends on how much of an angle of view you want to view of the object in your finished hologram. For example if 360 degree view of the subject is required, then you can expose 3 frames or stills per degree of movement around the subject. This will result in the exposure of 1080 frames.
  
  
• Second stage: When your film is developed, the next step is to make a series of "slit" holograms. Here you use each frame of film as a subject for each slit of holographic film. This is done in the holographic lab, using a laser. The slits are usually about one millimeter wide. These narrow strips capture the movement process only two-dimensionally, and then they are subsequently recorded on the hologram plate. They are packed together so close to each other that there is no "dead space" in between.
  
  
• Third stage: Also the hologram is bleached so that the strips disappear. The result is a hologram comprising more than 1000 different strip holograms.
  
  
  

Manufacturing Process of a Hologram

Information reference source from http://www.IHMA.org

A hologram is made by illuminating a 3-dimensional (3D) object in the powerful beam of laser light. Light waves that are reflected from the object makes a pattern. This pattern is recorded on a special type of holographic plate. When this is developed and light falls onto it, the original object is recreated. This image appears as a fully three-dimensional image. A large number of new creative possibilities is opened by holography using a new visual reality. Holography allows any artist to produce his type of work which on the other hand would be impossible in any other medium. There are nowadays advanced laser techniques with various art forms producing an entirely new level of artistic expression thereby creating an enchanting environment for home or office. Holograms are usually light and easy to send or carry and make a a wonderful gift or a fascinating addition to any collection.

Steps in making a hologram
Steps involved in producing a holographic image of an actual, three-dimensional object are as follows:

• Mastering
• 
  Step 1: A laser is used. This laser illuminates the physical object. The reflected light falls on the photoresist plate. At the same time, a reference beam from the laser falls directly on the photoresist plate. There is an interference between these two light beams which react with the photo-sensitive coating thereby recording a holographic image of the object.
  
  Step 2: The master is the plate on which the original hologram is recorded. The master is processed in a chemical bath using standard photographic developers after being exposed. The master is also expected to confirm that the image is properly recorded before proceeding with production.
  
  
• Electroforming
  Step 3: The master is mounted into frame. It is then sprayed with silver paint which helps in achieving good electrical conductivity. The frame is put inside a tank along with a supply of nickel. An electric current is produced, and the master is electroplated with nickel. The frame or jig is then removed from the tank and then it is washed with deionized water. The metal master shim, which is the thin, nickel coating, is removed off the master plate. This shim contains a negative image of the master hologram. The negative is the mirror image of the original hologram.
• 
  
  Using the same processes, several shims are created. Those that are produced from the metal master shim are known as "grandmothers,". "Grandmother shim" contains positive images of the original hologram. At this times, various copies of the original image are duplicated in rows on one shim and are used to print multiple copies with a single impression. Successive generations of shims are known by various names like "mothers," "daughters," and "stamper shims." These generations of shims alternate between negative and positive images of the original hologram. The stamper shims are used when actual production runs to print the final product holograms and these shims are negative images.
  
  
• Embossing
  Step 4: Stamper shims are put inside embossing machines. A roll of polyester film or other similar material, coated with an acrylic coating, runs through the machine. Under severe heat and pressure, the shim pushes the holographic image onto the film. This goes to a depth of 25 millionths of a millimeter. The embossed film is then re-wound onto a roll.
  
  
• Metallizing
  Step 5: The next step is to load the embossed film roll into a chamber from which the air is removed to create a vacuum. There is an aluminum wire in the chamber which is vaporized by heating it to 2000°F or 1,093°C. The roll is exposed to the vaporized aluminum and in turn another roll is formed and in the process the roll is coated with aluminum. The film is treated to restore moisture lost under the hot vacuum condition, after it is removed from the vacuum chamber. Another coating of lacquer is applied to the film and this creates a surface that can be imprinted with ink. The roll of film is again sliced into narrower rolls.
  
  
• Converting
  Step 6: There can be another step depending on what type of film was used and what kind of product is being made. For example, to give strength, the film can laminated to paper board. The film is given desired shapes for the final product. It can be printed with messages. Pressure-sensitive adhesive is applied to the back of holograms which can be later fixed to other objects or used as stickers.
  
  
• Finishing
  Step 7: For marketing, the final holograms are either fixed to other products or are packaged for shipment.