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US5220166A Expired / Lapsed US ⏱️ 0.0 years remaining

Information reading method

Assignee: Nemoto and Co Ltd
•
Filing: 1991-09-09
•
Granted: 1993-06-15
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Expires: 2011-09-09
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Abstract

Abstract An information reading method includes the steps of irradiating a phosphor activated by neodymium and ytterbium ions with exciting light of a wavelength between 500 nm and 780 nm that can excite the neodymium ions, and reading the information by receiving the light emitted from the phosphor with a photodetector designed to detect light with wavelengths between 840 m and 1100 nm. Consequently, the information recorded using the phosphor activated by neodymium and ytterbium ions can be read with a high performance without using a filter for cutting the exciting light.

Inventors

  • 👤 Nobuyoshi Takeuchi
  • 👤 Yuzo Ishikawa
  • 👤 Kaori Kanesaka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 17:59
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/10; G06K7/12

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 65 words
An information reading method comprising the steps of: irradiating a phosphor activated by neodymium and ytterbium ions with exciting light having a wavelength from 500 nm to 780 nm that can excite the neodymium ions; and reading the information by receiving the light emitted from the phosphor with a photodetector sensitive to light within a wavelength range from about 840 nm to about 1100 nm.
Claim 2
Dependent Claim 65 words
An information reading method comprising the steps of: irradiating a phosphor activated by neodymium and ytterbium ions with exciting light having a wavelength from 500 nm to 780 nm that can excite the neodymium ions; and reading the information by receiving the light emitted from the phosphor with a photodetector sensitive to light within a wavelength range from about 840 nm to about 1100 nm.
Claim 3
Dependent Claim 23 words
The information reading method according to claim 1, wherein the exciting light is emitted from a light-emitting element which is a semiconductor element.
Claim 4
Dependent Claim 22 words
The information reading method according to claim 1, wherein the wavelength range of the exciting light is from 650 to 780 nm.
Claim 5
Dependent Claim 22 words
The information reading method according to claim 1, wherein the wavelength range of the exciting light is from 550 to 650 nm.
Claim 6
Dependent Claim 22 words
The information reading method according to claim 1, wherein the wavelength range of the exciting light is from 500 to 550 nm.
Claim 7
Dependent Claim 42 words
The information reading method according to claim 1, wherein said phosphor comprises at least one type of compound activated by neodymium and ytterbium ions, said one type of compound being selected from the group consisting of phosphate, molybdate and aluminate type compounds.
Claim 8
Dependent Claim 42 words
The information reading method according to claim 6, wherein said phosphor comprises at least one type of phosphor selected from a group consisting of Me(Nd, Yb)P 4 O 12 and Me 5 (Nd, Yb)(MoO 4 ), wherein Me indicates an alkali metal.
Claim 9
Dependent Claim 35 words
The information reading method according to claim 1, wherein said phosphor is mixed into a material of a predetermined object during the manufacture of said predetermined object and is thereby recorded on said predetermined object.
Claim 10
Dependent Claim 34 words
The information reading method according to claim 1, wherein said phosphor is applied on a predetermined object in the form of a composition containing the phosphor and is thereby recorded on said predetermined object.
Claim 11
Dependent Claim 18 words
The information reading method according to claim 9, wherein said composition containing the phosphor is a coating composition.
Claim 12
Dependent Claim 17 words
The information reading method according to claim 9, wherein said composition containing the phosphor is an ink.
Claim 13
Dependent Claim 51 words
The information reading method according to claim 1, wherein said phosphor is recorded on one type of object made of a material selected from a plastic, paper, rubber, cloth, metal, ceramic, glass and a sheet coated with a compound containing magnetic powders from which information is read out using magnetic codes.
Claim 14
Dependent Claim 62 words
An information reading method comprising the steps of: irradiating a phosphor activated by neodymium and ytterbium ions with exciting light having peak wavelengths below 780 nm that can excite the neodymium ions; and reading the information by receiving the light emitted from the phosphor with a photodetector sensitive to light within a wavelength range from about 840 nm to about 1100 nm.
Claim 15
Dependent Claim 62 words
An information reading method comprising the steps of: irradiating a phosphor activated by neodymium and ytterbium ions with exciting light having peak wavelengths below 780 nm that can excite the neodymium ions; and reading the information by receiving the light emitted from the phosphor with a photodetector sensitive to light within a wavelength range from about 840 nm to about 1100 nm.

References Cited (Backward Citations)

US3566120A Cited
DE2318716A1 Cited
US3946203A Cited
JPS5433634A Cited
US4202491A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-06-14 1996-12-14 1997-06-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-06-14 2000-12-14 2001-06-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-06-14 2004-12-14 2005-06-15 $7700.00 Window Closed / Lapsed

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