Researchers Submit Patent Application, 'Volumetric Optically Variable Devices and Methods for Making Same', for Approval

摘要

News editors obtained the following quote from the background information supplied by the inventors: "Conventionally, a variety of techniques for producing holograms and other optically variable devices (OVDs) have been developed. These techniques generally involve utilizing the interference of two or more beams of coherent monochromatic light at the surface of a photosensitive material where the hologram or other OVD is produced. The monochromatic light is typically produced by a laser and, depending upon the desired result, the photosensitive material is chosen to produce a surface relief, gray scale, phase, or polarization holographic pattern. An OVD or VOVD is an iridescent image that exhibits various optical effects, such as movement and/or color changes. Advantageously, VOVDs cannot be photocopied or scanned, nor can they be accurately replicated or reproduced. Thus, VOVDs are often used as security devices and anti-counterfeiting measures on money, credit cards, government-issued identification cards, and the like. VOVDs are typically created through a combination of printing and embossing, and function via diffractive optical structures. Thus, different patterns, designs, and colors are created depending upon the amount of light striking a VOVD and the angle the VOVD is viewed at. Again, holograms are a type of VOVD.