| 摘要 |
In one embodiment, the invention provides a method for forming a full color laser engraved image on an ID card. As described below, a special image capable layer (200) is prepared that is addressable by one or more near infrared (NIR) lasers (208, 210, 212). Each type of particle (202, 204, 206) contained within the image capable layer (200) is associated with a particul ar color (e.g., cyan, magenta, or yellow) and is responsive (i.e., can selectively absorb) a particular wavelength of laser energy to form a laser engraved pixel in that respective color. In one embodiment, the particles (202, 204, 206) are selected such that the wavelengths that they respond to do not overlap significantly. By providing discrete physical particles and preventing a given particle from responding to more than one laser wavelengh t, it can be possible to minimize so-called "cross talk" between the cyan, magenta, and yellow centers and minimize contamination and/or chemical mixin g of image formers. This helps to ensure image accuracy and quality. |
