Abstract: A fingerprint ink pad arrangement, for use in taking rolled fingerprints, includes an ink reservoir formed of a porous material positioned against the inner wall of a cup shaped housing with a tubular substantially noncompressible ink dispensing substrate formed, for example, of a ceramic or plastic, positioned adjacent the ink reservoir so that ink flowing from the reservoir travels through the substrate to the fingerprint area.
Abstract: A nonstaining fingerprint ink is formulated from one or more alcohol soluble dyes, e.g., Acid Black 5 dye, dissolved in one or more fatty acid esters which have at least one available hydroxyl group, e.g., glycerol monoricinoleate, the dye constituting about 5% of the total ink by weight. An applicator, particularly well suited for the ink, includes a pad made of a melt blown calendared fabric encapsulated in a gas impermeable pouch.
Abstract: A one-dimensional scanner system for two-dimensional image acquisition includes a flying spot scanner for scanning in a line at a first velocity in a first direction across an object which is moving at a second velocity in a second direction transverse to the first direction; the first and second velocities establish a first sample rate in the second direction for defining a pixel size in the second direction; a timing device for detecting the velocity of the object in the second direction and generating a sample rate in the first direction and a frame accumulator for reading and storing each line scanned, assembling a two-dimensional image of the object and reading out that image; the frame accumulator including a compensation device responsive to the second sample rate for normalizing the second sample rate with the first sample rate to eliminate distortions in the pixel size and two-dimensional image in the first direction.
Type:
Grant
Filed:
October 28, 1996
Date of Patent:
November 23, 1999
Assignee:
Computer Identics, Inc.
Inventors:
David Jonathan Swithers, Thomas J. Chisholm
Abstract: A fingerprint ink is formulated from a solvent carrier and a low structure carbon dispersion. Carbon particles with an agglomerate size of less than 100 millimicrons are dispersed in a hydrocarbon soluble oleo resin to form the low structure carbon dispersion, with the carbon particles accounting for about 40% to 60% of the total dispersion and the dispersion accounting for 20% or less of the total ink formulation.
Abstract: A high-speed, high-resolution optical scanner system includes a flying spot scanner for scanning a beam across an object bearing information to be read and a high-bandwidth, high-sensitivity optical receiver including an avalanche photodiode for sensing the variation in light intensity of the beam reflected from the object being scanned; a power source for biasing the avalanche diode proximate its reverse breakdown voltage to produce high current gain in response to incident light; and a charge collector circuit responsive to the avalanche photodiode for producing a voltage proportional to the light incident on the avalanche photodiode.