OPTICAL READER FOR LUMINESCENT CODES LUMINESCING IN DIFFERENT WAVELENGTHS

• US 3,663,813 A
• Filed: 01/19/1970
• Issued: 05/16/1972
• Est. Priority Date: 01/19/1970
• Status: Expired due to Term

• Current Assignee: Robert Frank Shaw
• Original Assignee: Robert Frank Shaw
• Inventors: Shaw, Robert Frank
• Primary Examiner(s): Frome, Morton J.
• Application Number:
  US05/003,992
• Time in Patent Office: 848 Days
• Field of Search: 250/71,71.5,83.3,226 350/315 235/61.115 356/100,83
• US Class Current: 250/271
• CPC Class Codes: G01J 3/4406 Fluorescence spectrometry
• CPC Class Codes: G06K 7/12 using a selected wavelength, e.g. to sense red marks and ignore blue marks
• CPC Class Codes: G07D 7/06 using wave or particle radiation
• CPC Class Codes: G11C 13/048 using other optical storage elements

Abstract

Symbols formed by marking a substrate with coded inks, the coding represented by the absence or presence in one or more levels of one or more photoluminescent components, are irradiated with ultraviolet light and the photoluminescence from the various coding components is projected through a dispersing agent, such as a prism or a grating, onto the sensitive surface of a television camera tube, such as a vidicon or orthicon, the output of the camera tube producing electrical pulses in each scan corresponding to the position of the various photoluminescent colors. The output can be read out on an oscilloscope or other readout device synchronized with the television camera electron scan. The presence of coding components are represented by pulses in corresponding positions and the height of the pulses can represent the level of component concentration if it is present in more than one concentration.

Claims

1. A method for processing information comprising a. providing said information as a coded symbol marking area in which the code is the presence or absence of at least one level of photoluminescing components, each component luminescing under excitation from ultraviolet light in at least one wavelength band not shared by any other component, b. illuminating said symbol marking area with ultraviolet light, causing photoluminescence in the bands corresponding to the particular coding components present, c. projecting said photoluminescence into a light beam, d. dispersing said beam into different wavelength bands and projecting these bands on a photosensitive surface, e. scanning said photosensitive surface with an electron beam to produce a pulse train with pulses corresponding to each dispersed wavelength band, and f. detecting said pulses to read said coded symbol.

2. A readout mechanism according to claim 1 in which the electron beam scanned photosensitive surface is part of a television camera tube.

3. A method according to claim 1 in which pulses of different characteristics are produced by different intensities of dispersed beams, whereby readout of coded symbols in which the code constitutes the absence or the presence in more than one level of photoluminescent components is effected.

4. A readout mechanism according to claim 1 including means to display said pulse train.