US3904872A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Detector for luminescent patterns comprising a color detector responsive to color components of predetermined colors of the luminescence
Assignee: NEC Corp
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Filing: 1973-11-21
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Granted: 1975-09-09
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Expires: 1993-11-21
Abstract
Abstract A pattern capable of emitting luminescence of at least one predetermined color is intermittently excited. The luminescence emitted thereby is subjected to color and intensity recognition and then to duration recognition to discriminate between fluorescence and phosphorescence of the predetermined color as well as to discriminate the fluorescence and phosphorescence of the pattern from spurious luminescence. The color and intensity recognition is carried out by a small number of phototubes sensitive to the rays of more than one color component, one of the color components or one combination of the color components being the predetermined color of the luminescence, and by a color detector responsive to the output signals of the phototubes for producing logic signals corresponding to the detection of the color components and at least one combination of the color components, each logic signal assuming a preselected one of logic ''''1'''' and ''''0'''' levels when the intensity of the rays of the corresponding color component or the selected combination of the color components is above a predetermined magnitude.
Inventors
- 👤 Rinzou Ebukuro
- 👤 Tomoyuki Isono
- 👤 Tetsuo Omiya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 00:39
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/62; G01N21/63; G01N21/64; G01N21/6408; G01N2021/6413
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
212 words
An electro-optical detection device which is capable of discriminating between a plurality of patterns having different luminescent materials thereon, each luminescent material, when excited, emitting luminescence whose color is identical to one of a plurality of predetermined colors and whose persistence characteristic is such that it will decay to zero luminescence in less than or longer than a predetermined time, comprising: a plusating radiation source for directing radiation upon said patterns to excite said luminescent materials thereon for luminescence, said radiation having a predetermined pulse frequency with its ''''off'''' period of each cycle equal to said predetermined time; photosensitive detector means responsive to the luminescence from said luminescent materials for generating first electric signals proportional to the intensities of predetermined color components of which each of said predetermined colors is composed; color detecting means responsive to said first electric signals for generating second electric signals indicative of the presence of said predetermined colors in the luminescence from said luminescent materials; duration distinguishing means responsive to said second electric signals for generating third electric signals indicative of whether the luminescence from said luminescent materials has a decay time less than or longer than said predetermined time; and recognition means responsive to said second and third electric signals for recognizing said plurality of patterns.
Claim 2
Dependent Claim
212 words
An electro-optical detection device which is capable of discriminating between a plurality of patterns having different luminescent materials thereon, each luminescent material, when excited, emitting luminescence whose color is identical to one of a plurality of predetermined colors and whose persistence characteristic is such that it will decay to zero luminescence in less than or longer than a predetermined time, comprising: a plusating radiation source for directing radiation upon said patterns to excite said luminescent materials thereon for luminescence, said radiation having a predetermined pulse frequency with its ''''off'''' period of each cycle equal to said predetermined time; photosensitive detector means responsive to the luminescence from said luminescent materials for generating first electric signals proportional to the intensities of predetermined color components of which each of said predetermined colors is composed; color detecting means responsive to said first electric signals for generating second electric signals indicative of the presence of said predetermined colors in the luminescence from said luminescent materials; duration distinguishing means responsive to said second electric signals for generating third electric signals indicative of whether the luminescence from said luminescent materials has a decay time less than or longer than said predetermined time; and recognition means responsive to said second and third electric signals for recognizing said plurality of patterns.
Claim 3
Dependent Claim
87 words
The device of claim 1 wherein said color detector comprises: amplifier means responsive to said first electric signals for producing normalized analog electric signals, potentiometer means for adjustably producing allowance electric signals indicative of at least one amount predetermined in conjunction with every one of said color components, and adder/comparator means responsive to said normalized electric signals and said allowance electric signals for producing said second electric signals when the algebraic sum of the concerned normalized electric signals and the concerned allowance is of a predetermined polarity.
Claim 4
Dependent Claim
75 words
The device of claim 1 wherein said duration distinguishing means comprises: integrator means for integrating said second electric signals, said integrator means producing at its output an intermittent signal not reaching a predetermined level when the luminescence from said luminescent materials has a decay time less than said predetermined time and a substantially continuous signal reaching said predetermined level when the luminescence from said luminescent materials has a decay time Longer than said predetermined time.
Claim 5
Dependent Claim
28 words
The device of claim 1 wherein said duration distinguishing means comprises: logic gate means for passing said second and third electric signals therethrough upon coincidence of said signals.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-08 | 1979-03-10 | 1979-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-08 | 1983-03-10 | 1983-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-08 | 1987-03-10 | 1987-09-09 | $7700.00 | Window Closed / Lapsed |