Method for discriminating authenticity of a bill using polarizat

Details Method for discriminating authenticity of a bill using polarizat Method for discriminating authenticity of a bill using polarizat

1989-09-27

1991-02-05

Nelms, David C.

Radiant energy

Photocells; circuits and apparatus

Photocell controlled circuit

250225, 356369, G06K 500

Patent

active

049907905

ABSTRACT:
An apparatus for discriminating the authenticity of a bill put into an automatic vending machine, etc. on the basis of a degree of brilliance of a surface of the bill, comprises two photodiodes for receiving light irradiated from a light-emitting diode and reflected by the bill, and a polaroid filter disposed in front of one of the photodiodes. A differential amplifier or a divider is supplied with output currents from the photodiodes, respectively representing an amount of the reflected light received not through the polaroid filter and containing a polarized component which is produced when the light is reflected on the surface of the bill, and an amount of the reflected light, received through the filter and containing no polarized component, and generates an output voltage indicative of the difference between or the ratio of the output currents, which voltage is compared with a corresponding reference voltage in a comparator whose output assumes a Low-level for a lusterless authentic bill, and a High-level for a brilliant counterfeit bill obtained by color-copying the authentic bill, whereby the authenticity of the bill is accurately discriminated.

REFERENCES:
patent: 3496370 (1970-02-01), Haville et al.
patent: 3497304 (1970-02-01), Berube
patent: 4250393 (1981-02-01), Greenaway
patent: 4526466 (1985-07-01), Sandercock

Affiliated with

Also associated with

Rating

Method for discriminating authenticity of a bill using polarizat does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for discriminating authenticity of a bill using polarizat, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for discriminating authenticity of a bill using polarizat will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-11898