Apparatus for testing the presence of color in a paper security

摘要

Disclosed is apparatus for determining the authenticity of paper purported to be valid currency or the like. The invention includes a sliding tray which is adapted for receiving the paper. Maintained above the tray are a light source and three photocells. The light source casts light upon the paper as the tray is passed thereunder and light is reflected from the paper's surface onto two of the photocells. Appropriate filtering causes each of the two photocells to respond to different wavelengths of light reflected from the paper, these wavelengths corresponding to colors known to be present along the path traveled by the paper as it passes under the photocells. The outputs of the photocells are thus indicative of the presence and relative positions of colored areas upon the surface of the paper. Circuitry is included to receive and compare the outputs of the photocells with each other and with the output of a reference photocell, thereby determining the authenticity of the paper. The apparatus may be used in conjunction with a reticle validation test apparatus as a secondary validation test.