Glossary Get to know a list of certain terms associated with hologram and holographic technique: Animated holograms: They are made by using time-lapse photography. The object moves between exposures. The object appears to move as the viewpoint changes when the hologram is made from these photos. They are made up of hundreds of image channels Beamsplitter: This is a device which divides the light from a laser into two separate beams-the reference beam and the object beam. Channels: They are images in a hologram which change instantly from one to another as the viewer passes by. These images can also fade or overlap as they change. Coherent light: A coherent light is made from laser and this light is of the same frequency and vibrates in phase. Computer generated hologram: This is a hologram made from a three-dimensional computer model. 2D/3D Hologram: The hologram is made of multiple 2D layers with hologram images placed one behind another with visual depth that creates an effect of three-dimensional hologram structure. Diffraction: Bending of light as it passes through very small openings. Dennis Gabor: He is a physicist from Hungary who discovered the holographic technique and was awarded the nobel prize in 1971. DOT-MATRIX Hologram: Dot-Matrix Hologram create a beautiful impact of variable images allowing unlimited computer controlled and laser beam engraved dots in hologram. Embossed holograms: They are made by a manufacturing process which uses a metal replica of a master hologram. Film: Film consists of light sensitive chemicals or the emulsion spread on a surface. Flip-Flop Holograms: They can display two images from different viewing angle. Full color: They represent the natural subject colors as in color photography. Hologram: A hologram is a record of an image as seen from many viewpoints, giving a three-dimensional effect. Holography: The process of making hologram is known as holography. HOE's: These are Holographic Optical Elements, which are actually produced to perform the function of traditional optics, like mirrors and lenses. Interference pattern: A hologram is formed when two waves overlap. This results in an interference pattern which records the relative phase relationship between the two waves. Master hologram: The first hologram that is formed and viewable only by laser light, and combined with other masters for the final hologram transfer. Multiplex holograms: They are stereoscopic holograms made by taking an array of photos with the camera tracking past a subject. Object beam: The light from a laser beam that illuminated the object and is reflected to the holographic film. Rainbow holograms: They are transmission holograms where the object appears to change color as the viewpoint moves vertically. Reference beam: The portion of a laser beam that goes directly to the holographic film. Reflection hologram: Reflection holograms are viewed with the light source on the same side of the viewer. The light is reflected off the hologram. Stereogram: This is an alternative to the original hologram process. Here the subject is imaged directly onto the film with a laser exposure. Tamper evident: Instant recognition of tampering. Transmission hologram: Transmission holograms are lit from behind or viewed with the light source on the opposite side of the hologram from the viewer. Here the light transmits through the hologram. Transfer holograms: These holograms are made using a holographic image from a "master" hologram as the object of a second hologram. True Color Hologram: True Color Hologram is made up of photographic quality art-work, in which counterfeiters can't duplicate hologram close to original one. Volume Hologram: The angle difference between the object beam and reference beam is equal to or greater than 90 degrees. White light: White light is incoherent and contains most of the wavelengths in the visible spectrum, like light from the sun or from a spotlight.