Abstract: A light source is configured to emit a narrow peak at a discrete spectral band, especially at a primary color wavelength. The light source can have a plurality of narrow peaks to simulate the effect of a broadband light source. A subject is provided with a pigment, such as certain rare earth lanthanides, with a strong absorption peak at a corresponding narrow spectral band. The pigment has a nominal color when illuminated by a true broadband light (e.g., sunlight) that does not have a narrow peak at the discrete spectral band, and has a different color when illuminated by the light source that has a narrow peak. This color shift can be used for security authentication, information and decorative applications.

Abstract: A light source is configured to emit a narrow peak at a discrete spectral band, especially at a primary color wavelength. The light source can have a plurality of narrow peaks to simulate the effect of a broadband light source. A subject is provided with a pigment, such as certain rare earth lanthanides, with a strong absorption peak at a corresponding narrow spectral band. The pigment has a nominal color when illuminated by a true broadband light (e.g., sunlight) that does not have a narrow peak at the discrete spectral band, and has a different color when illuminated by the light source that has a narrow peak. This color shift can be used for security authentication, information and decorative applications.

Abstract: A light source is configured to emit narrow peaks at discrete spectral bands, especially primary color wavelengths, added to simulate the effect of a broadband light source. A subject is provided with a pigment, examples being certain rare earth lanthanides, with a strong absorption peak at a corresponding narrow spectral band. The pigment has a nominal hue under true broadband light. When illuminated by the narrow band source, the absorption peak eliminates the contribution of one of the primary colors, producing a distinct shift in hue of the pigmented subject. The change in hue cannot be anticipated from the appearance of illuminated subjects that lack the pigment, which remain normal. The narrow absorption peak is not noticeable under unmatched light sources or true broadband light sources, e.g., sunlight. The hue shift effect is useful for security authentication, informational and decorative applications.

Abstract: A light source is configured to emit narrow peaks at discrete spectral bands, especially primary color wavelengths, added to simulate the effect of a broadband light source. A subject is provided with a pigment, examples being certain rare earth lanthanides, with a strong absorption peak at a corresponding narrow spectral band. The pigment has a nominal hue under true broadband light. When illuminated by the narrow band source, the absorption peak eliminates the contribution of one of the primary colors, producing a distinct shift in hue of the pigmented subject. The change in hue cannot be anticipated from the appearance of illuminated subjects that lack the pigment, which remain normal. The narrow absorption peak is not noticeable under unmatched light sources or true broadband light sources, e.g., sunlight. The hue shift effect is useful for security authentication, informational and decorative applications.

Abstract: A light source is configured to emit narrow peaks at discrete spectral bands, especially primary color wavelengths, added to simulate the effect of a broadband light source. A subject is provided with a pigment, examples being certain rare earth lanthanides, with a strong absorption peak at a corresponding narrow spectral band. The pigment has a nominal hue under true broadband light. When illuminated by the narrow band source, the absorption peak eliminates the contribution of one of the primary colors, producing a distinct shift in hue of the pigmented subject. The change in hue cannot be anticipated from the appearance of illuminated subjects that lack the pigment, which remain normal. The narrow absorption peak is not noticeable under unmatched light sources or true broadband light sources, e.g., sunlight. The hue shift effect is useful for security authentication, informational and decorative applications.

Abstract: A light source is configured to emit narrow peaks at discrete spectral bands, especially primary color wavelengths, added to simulate the effect of a broadband light source. A subject is provided with a pigment, examples being certain rare earth lanthanides, with a strong absorption peak at a corresponding narrow spectral band. The pigment has a nominal hue under true broadband light. When illuminated by the narrow band source, the absorption peak eliminates the contribution of one of the primary colors, producing a distinct shift in hue of the pigmented subject. The change in hue cannot be anticipated from the appearance of illuminated subjects that lack the pigment, which remain normal. The narrow absorption peak is not noticeable under unmatched light sources or true broadband light sources, e.g., sunlight. The hue shift effect is useful for security authentication, informational and decorative applications.

Abstract: A discriminator for coins and tokens monitors the extent to which an alternating electromagnetic field is coupled through a deposited coin and a reference coin, as the deposited coin passes along a feed path. A first electromagnetic field is incident on a reference coin along an axis normal to the reference coin and displaced from a midpoint of the reference coin. As the deposited coin moves through a second electromagnetic field traversing the feed path, the deposited coin passes two positions at which the second electromagnetic field is aligned to the deposited coin to a same degree as the first electromagnetic field is aligned to the reference coin. The electromagnetic fields preferably are provided by two series connected coils in a stack, and the fields passing through the coins are added at opposite polarity by a receiver coil placed between the series connected coils (and also between the sample coin and the deposited coin).

Abstract: A token for use, for example, in the gaming, vending, toll collection and amusement industries, has identifying indicia for automated discrimination of a token identification such as the issuing entity, denomination or the like. The token has a body, substantially shaped as a flat disk having opposite surfaces, with code marks impressed or minted directly into the token face surfaces on one or both opposite sides. The identification marks include surface variations aligned at least partly at an angle relative to a plane of the token surface, the marks being detectable as reflective or non-reflective variations, for example by an optical detector or by an optical emitter-detector pair. The identification marks can be annular rings or transverse variations elongated in a direction extending from a center to an edge of the token, which token preferably is round.

Abstract: A rapid coin acceptor is disclosed which is capable of discriminating valid coins or tokens from counterfeit coins or tokens and for accepting the valid coins or tokens as they fall by gravity through the device. The coin acceptor includes a coin introduction chute which receives coins or tokens and directs the coins by gravity feed to a coin sensing gate which is positioned in vertical registry below the bottom of the coin introduction chute. The coin sensing gate is equipped with a plurality of sensors to sense various parameters of the coin or token for authentication purposes as the coin or token drops through the coin sensing gate. The coin sensing gate is designed of height between one and one and one-half times the diameter of the coin to assure substantially instantaneous response to prevent the rapid insertion of a spurious coin from defeating the sensor control.