SYSTEM FOR AUTHENTICATING AN OBJECT
A system for authenticating an object ( 12 ) includes an object having fluorescent indicia ( 14 ), wherein the indicia includes at least two different types of particles which fluoresce upon exposure to light ( 15 ) and which have different decay rates, a lamp ( 32 ) for exposing the indicia to light and causing the plurality of particles to fluoresce, a sensor ( 22 ) for capturing at least a first image of the indicia at a first time and a second image of the indicia at a second time different from the first time, means for analyzing the images to determine decay rates of the at least two types of particles, and means for authenticating the object if the decay rates match stored information.
1 . A system for authenticating an object comprising:
an object having fluorescent indicia, wherein the indicia comprises at least two different types of particles which fluoresce upon exposure to light and which have different decay rates;
a lamp for exposing the indicia to light and causing the plurality of particles to fluoresce;
a sensor for capturing at least a first image of the indicia at a first time and a second image of the indicia at a second time different from the first time;
means for analyzing the images to determine decay rates of the at least two types of particles; and
means for authenticating the object if the decay rates match stored information.
2 . The system of claim 1 wherein the sensor is a sensor for capturing a third image of the indicia at a third time prior to analyzing the images to determine decay rates.
3 . The system of claim 2 wherein the first, second, and third times are regularly spaced in time.
4 . The system of claim 2 wherein the first, second, and third times are irregularly spaced in time.
5 . The system of claim 1 wherein the second time is dependent on the analysis of the first image.
6 . The system of claim 1 wherein the light is selected from a group comprising IR, UV, and visible light.
7 . The system of claim 1 wherein the lamp is a lamp for exposing the indicia to light a second time so that at least one type of particle emits more light after the second exposure than the particle emits after the first exposure.
8 . The system of claim 1 , further including a display for displaying the images.
9 . The system of claim 1 , further including a display for displaying authentication.
10 . The system of claim 1 further including a receiver for receiving an indication of authenticity from a remote computer.
11 . The system of claim 1 further including a transmitter for transmitting the images to a remote computer.
12 . The system of claim 1 wherein the sensor is an image sensor.
13 . The system of claim 1 wherein the means for analyzing is a microprocessor.
14 . The system of claim 1 wherein the means for authenticating is a microprocessor.
15 . The system of claim 1 further including a camera having a flash and an image sensor.
16 . The system of claim 15 further including a microprocessor.
17 . The system of claim 15 wherein the camera flash is a visible-light flash and the image sensor is a visible light image sensor, and further including a conversion device mounted over the camera flash which converts the emitted visible light to UV light.
18 . The system of claim 17 wherein the conversion device comprises:
a photovoltaic device that converts the visible light emitted by the camera flash to electrical power; and
a UV lamp that converts the electric power to UV light.
19 . The system of claim 15 wherein the camera is a cell phone camera and the system includes a cell phone or smart phone.
20 . The system of claim 1 wherein the indicia changes color over time.