Fluorescent substance, fluorescent composition, fluorescent mark carrier and optical reader therefor
AssigneeHitachi Maxell, Ltd.
InventorsToshio Oshima, Yukinori Yamada, Shoji Saibara, Takanori Kamoto, Tomio Nabeshima
Life of this patent
Estimating the term…
Abstract
A fluorescent substance of the following general formula: LnXA1-XPO4 wherein Ln represents at least one element selected from the group consisting of Nd, Yb and Er; A represents at least one element selected from the group consisting of Y, La, Gd, Bi, Ce, Lu, In and Tb; and X represents a value within the range of 0.01 to 0.99.
Claims119
A fluorescent substance of a kind capable of emitting, in response to irradiation of exciting light, a fluorescent light of a wavelength different from that of the exciting light, characterized in that the average particle size of the fluorescent substance is smaller than the wavelength of the fluorescent light at the maximum intensity of such fluorescent light emitted by such fluorescent substance.
A fluorescent substance of a kind capable of emitting, in response to irradiation of exciting light, a fluorescent light of a wavelength different from that of the exciting light, characterized in that the average particle size of the fluorescent substance is smaller than the wavelength of the fluorescent light at the maximum intensity of the exciting light.
A fluorescent substance characterized in that it comprises a salt of oxyacid containing at least one optical active element selected from the group consisting of Nd, Yb and Er.
A fluorescent substance characterized in that it comprises Fe and Er, both as an optical active element, and, other than these optical active elements, at least one element selected from the group consisting of Sc, Ga, Al, In, Y, Bi, Ce, Gd, Lu and La.
A fluorescent substance characterized in that it comprises Yb as an optical active element and, other than that optical active element, at least one element selected from the group consisting of Sc, Ga, Al, In, Y, Bi, Ce, Gd, Lu and La.
A fluorescent substance characterized in that it comprises at least one organic substance containing rare earth element, said organic substance being selected from the group consisting of Nb, Yb and Er and carried with an organic substance having an absorption band within the infrared region of light.
A fluorescent substance characterized in that it contains at least one of Nb and Yb as an optical active element and, other than this optical active element, at least one oxide of Mo or W and an alkaline earth metal.
A method of preparing a fluorescent substance characterized in that at least one optical active element selected from the group consisting of Nd and Yb, at least one oxide of one of Mo and W and an alkaline earth metal are added to a flux material containing a salt expressed by T2RO4·nH2O (wherein T is at least one element selected from the group consisting of Li, Na and K, R is at least one element selected from the group consisting of Mo and W, and n is a value greater than 0) which is subsequently calcinated, followed by dissolution of the incinerated product with the use of a solvent to remove the flux material.
A fluorescent composition characterized in that it comprises a fluorescent substance in the form of ultra-microparticles capable of emitting a fluorescent light of a wavelength different from that of an exciting light and having an average particle size smaller than the wavelength of the maximum intensity of the fluorescent light, a binder transparent to both of the exciting light and the fluorescent light, and a solvent.
A fluorescent composition characterized in that it comprises a fluorescent substance in the form of ultra-microparticles capable of emitting a fluorescent light of a wavelength different from that of an exciting light and having an average particle size smaller than the wavelength of the maximum intensity of the exciting light, a binder transparent to both of the exciting light and the fluorescent light, and a solvent.
The fluorescent composition as defined in any one of claims 41 to 46, characterized in that the fluorescent substance is comprised of an organic metallic compound.
A fluorescent composition characterized in that it comprises a fluorescent substance containing at least one organic substance which contains a rare earth element and which is selected from the group consisting of Nb, Yb and Er carried with an organic substance having an absorption band within the infrared region of light, and an organic binder.
A fluorescent composition characterized in that it comprises a fluorescent substance containing at least one of Nb and Yb as an optical active element and, other than this optical active element, at least one oxide of one of Mo and W and an alkaline earth metal, and an organic binder.
An inked ribbon characterized in that it comprises a tape-like carrier deposited with a fluorescent composition comprising a fluorescent substance containing at least one of Nb and Yb as an optical active element and, other than this optical active element, at least one oxide of one of Mo and W and an alkaline earth metal, which fluorescent substance is dispersed and retained in an organic binder.
A fluorescent mark carrier characterized in that it has a fluorescent ink deposit formed thereon, said fluorescent ink deposit containing a fluorescent substance capable of emitting a fluorescent light of a wavelength different from that of the exciting light and having an average particle size smaller than the wavelength of the maximum intensity of the fluorescent light is printed thereon.
A fluorescent mark carrier characterized in that it has a fluorescent ink deposit formed thereon, said fluorescent ink deposit containing a fluorescent substance capable of emitting a fluorescent light of a wavelength different from that of the exciting light and having an average particle size smaller than the wavelength of the maximum intensity of the exciting light is printed thereon.
A fluorescent mark carrier having a fluorescent ink deposit formed thereon, said fluorescent ink deposit containing fluorescent particles capable of emitting a fluorescent light of a wavelength different from that of an exciting light, characterized in that the content of said fluorescent particles in the fluorescent ink deposit is greater than 1 wt %, but smaller than 30 wt %.
A fluorescent mark carrier having a fluorescent ink deposit formed thereon, said fluorescent ink deposit containing fluorescent particles capable of emitting a fluorescent light of a wavelength different from that of an exciting light, characterized in that the fluorescent ink deposit has a thickness not greater than 35 times the particle size of the fluorescent particles.
A fluorescent mark carrier having a fluorescent ink deposit formed thereon, said fluorescent ink deposit containing fluorescent particles capable of emitting a fluorescent light of a wavelength different from that of an exciting light and a binder, characterized in that the binder has a light transmissivity with respect to each of the exciting and fluorescent light being not lower than 80%.
A fluorescent mark carrier characterized in that fluorescent particles capable of emitting a fluorescent light of a wavelength different from that of an exciting light are deposited on an aggregation of fibers.
A fluorescent mark carrier characterized in that a fluorescent ink deposit containing a fluorescent substance capable of emitting a fluorescent light of a wavelength different from that of an exciting light has a 20% or lower visible ray absorption characteristic.
An optical reading apparatus comprising a light emitting element for emitting an exciting light to irradiate a fluorescent mark carrier carrying a fluorescent mark containing the fluorescent substance, a mirror for reflecting light from the fluorescent substance, and a light receiving element for receiving the light reflected by the mirror, characterized in that the mirror has a portion thereof provided with a light transmitting region for allowing a substantially entire quantity of the exciting light from the light emitting element to pass therethrough and has a reflectivity of higher than 50%.
The optical reading apparatus as defined in claim 99, characterized in that the light transmitting region is of a size greater than a bundle of the exciting light.
An optical reading apparatus comprising a light emitting element for emitting an exciting light to irradiate a fluorescent mark carrier carrying a bar code containing the fluorescent substance, and a light receiving element for receiving light from the fluorescent substance, characterized in that the exciting light is projected in an irradiating pattern of a generally elliptical shape having its major axis extending in a direction lengthwise of the bar code.
An optical reading apparatus comprising a light emitting element for emitting an exciting light to irradiate a fluorescent mark carrier printed with the fluorescent substance, a light receiving element for receiving a fluorescent light from the fluorescent mark carrier, a slit member disposed on an optical path between the light emitting element and the light receiving element, and a transport means for transporting the fluorescent mark carrier in a predetermined direction, characterized in that the transport means transports the fluorescent mark carrier at a velocity v which has the following relationship:
- d/v≧tu
- wherein d represents the length of an opening in the slit member as measured in a direction conforming to the direction of transport of the fluorescent mark carrier, v represents the velocity of transport of the fluorescent mark carrier and tu represents the length of time from the timing at which the fluorescent substance receives the exciting light to the timing at which the intensity of the light emitted by the fluorescent substance attains 90% of the maximum possible intensity thereof.
An optical reading apparatus comprising a light emitting element for emitting an exciting light to irradiate a fluorescent mark carrier printed with the fluorescent substance, a light receiving element for receiving a fluorescent light from the fluorescent mark carrier and a transport means for transporting the fluorescent mark carrier in a predetermined direction, which apparatus is characterized in that the transport means transports the fluorescent mark carrier at a velocity v which has the following relationship:
- L/v≧td
- wherein L represents the interval between neighboring portions printed with the fluorescent substance with respect to the direction of transport, v represents the velocity of transport of the fluorescent mark carrier, and td represents the length of time from the timing at which irradiation of the exciting light is interrupted to the timing at which the fluorescent afterglow attenuates by a quantity corresponding to 80% of the maximum possible intensity thereof.
An optical reading apparatus characterized in that it comprises a light emitting element for emitting an exciting light to irradiate a fluorescent mark carrier carrying the fluorescent substance, a light receiving element for receiving a fluorescent light from the fluorescent mark carrier, a transport means for transporting the fluorescent mark carrier in a predetermined direction, a first convex lens disposed on an optical path from the fluorescent mark carrier to the light receiving element and having a flat surface oriented towards the fluorescent mark carrier, a second convex lens disposed on an optical path from the fluorescent mark carrier to the light receiving element and having a flat surface oriented towards the light receiving element, and a slit member disposed between the second convex lens and the light receiving element.
An optical reading apparatus characterized in that it comprises a light emitting element for emitting an exciting light to irradiate a fluorescent mark carrier printed with the fluorescent substance, and a light receiving element for receiving a fluorescent light from the fluorescent mark carrier, characterized in that the light emitting element is a semiconductor laser diode, a drive circuit for driving the semiconductor laser diode having an automatic power control function, and there is provided a hold circuit for monitoring the exciting light emitted from the semiconductor laser diode and holding an output condition of the exciting light such that based on a signal from the hold circuit an output condition of the exciting light from the semiconductor laser diode is controlled by the drive circuit.
A merchandise sorting apparatus which comprises:
- a light emitting element for emitting an exciting light to irradiate a fluorescent mark carrier printed with the fluorescent substance;
- a light emitting element for receiving a fluorescent light from the fluorescent mark carrier;
- a slit member disposed on an optical path between the light emitting element and the light receiving element;
- a transport means for transporting the fluorescent mark carrier in a predetermined direction;
- and
- a sorting means for sorting the fluorescent mark carrier;
- wherein the length d of an opening in the slit member as measured in a direction conforming to the direction of transport of the fluorescent mark carrier, the velocity v of transport of the fluorescent mark carrier by the transport means, and the length of time tu from the timing at which the fluorescent substance receives the exciting light to the timing at which the intensity of the light emitted by the fluorescent substance attains 90% of the maximum possible intensity thereof have a relationship of (d/v≧tu);
- and
- wherein information represented by a fluorescent ink deposit provided on the fluorescent mark carrier is read by the exciting light and the fluorescent light passing through a slit formed in the slit member, said fluorescent mark carrier being sorted according to such information.
A merchandise sorting apparatus which comprises:
- a light emitting element for irradiating with the exciting light a fluorescent mark carrier printed with the fluorescent substance;
- a light emitting element for receiving a fluorescent light from the fluorescent mark carrier;
- a slit member disposed on an optical path between the light emitting element and the light receiving element;
- a transport means for transporting the fluorescent mark carrier in a predetermined direction;
- and
- a sorting means for sorting the fluorescent mark carrier;
- wherein the interval between neighboring portions printed with the fluorescent substance with respect to the direction of transport, the velocity v of transport of the fluorescent mark carrier, and the length of time td from the timing at which irradiation of the exciting light is interrupted to the timing at which the fluorescent afterglow attenuates by a quantity corresponding to 80% of the maximum possible intensity thereof have a relationship of (L/v≧td);
- and
- wherein information represented by a fluorescent ink deposit provided on the fluorescent mark carrier being transported is optically read and the fluorescent mark carrier is sorted according to such information.
A merchandise sorting apparatus which comprises:
- an visible image optical reading means for optically reading destination information described on a surface of a merchandise to be sorted;
- a fluorescent substance printing means for printing the destination information on the merchandise with the use of a fluorescent substance according to the destination information read by the visible image optical reading means;
- a fluorescent mark optical reading means for optically reading information represented by a fluorescent ink deposit formed by the fluorescent substance printing means;
- and
- a sorting means for sorting the merchandise according to the destination information read by the fluorescent mark optical reading means.
A merchandise sorting method which comprises the steps of:
- optically reading destination information described on a surface of a merchandise with the use of a visible image optical reading means;
- printing destination information on the merchandise with the use of a fluorescent substance according to the destination information read by the visible image optical reading means,;
- optically reading information represented by a fluorescent ink deposit with the use of a fluorescent mark optical reading means;
- and
- sorting the merchandise according to the destination information read by the fluorescent mark optical reading means.
A mark to be detected containing a fluorescent substance capable of emitting light of a wavelength different from that of an exciting light, characterized in that it comprises:
- a data area formed with a pattern corresponding to data to be recorded;
- and
- a lead-in area formed at a site that is scanned prior to irradiation with the exciting light upon the data area, said lead-in area continuing a sufficient length greater than the longest continuous portion of the pattern formed at the data area.
A method of detecting a mark by irradiating the mark, containing the fluorescent substance, with an exciting light and receiving a fluorescent light emitted from the mark, which method comprises the steps of:
- a step of intermittently projecting the exciting light of a substantially constant intensity;
- a step of receiving light, emitted from an irradiating position of the exciting light and converting it into an electric signal;
- an incident light intensity detecting step of outputting as a comparison value an electric signal corresponding to the intensity of incident light during an irradiating period;
- a fluorescent intensity detecting step of outputting, as a detected value, an electric signal indicative of the magnitude of a fluorescent component of the incident light;
- and
- a determining step of comparing the detected value with a comparison value and determining, in the event that the detected value exceeds the comparison value, the position at which the mark is formed.
An optical reading apparatus for detecting a mark by irradiating the mark to be detected, containing a fluorescent substance capable of emitting light of a wavelength different from that of an exciting light, with the exciting light and receiving a fluorescent light emitted from the mark, which apparatus comprises:
- a light irradiating means for projecting the exciting light of a substantially constant intensity intermittently at a predetermined cycle;
- a photoelectric converting means for receiving the light emitted from a light emitting position and converting it into an electric signal;
- a waveform detecting means synchronized with an irradiating timing of the light irradiating means for making it possible to individually detect a minimum value shortly before start of the irradiation;
- a maximum value shortly before interruption of the irradiation and a detected value immediately after interruption of the irradiation;
- and
- a mark determining means for comparing the detected value with a comparison value obtained by dividing the difference between the maximum value and the minimum value and for determining, in the event that the detected value exceeds the comparison value, the position at which the mark is formed.
An optical reading apparatus for detecting a mark by irradiating the mark to be detected, containing the fluorescent substance capable of emitting light of a wavelength different from that of an exciting light, with the exciting light and receiving a fluorescent light emitted from the mark, which apparatus comprises:
- a light irradiating means for projecting the exciting light of a substantially constant intensity intermittently at a predetermined cycle;
- a photoelectric converting means for receiving the light emitted from a light emitting position and converting it into an electric signal;
- a waveform shaping means for inverting and amplifying half of an output signal from the photoelectric converting means in synchronism with a timing displaced 90° relative to a period of irradiation by the light irradiating means;
- and
- a low-pass filtering means for selectively outputting a direct current component from the output signal of the waveform shaping means.
An optical reading apparatus for detecting a mark by irradiating the mark to be detected, containing the fluorescent substance capable of emitting light of a wavelength different from that of an exciting light, with the exciting light and receiving a fluorescent light emitted from the mark, which apparatus comprises:
- a light irradiating means for projecting the exciting light of a substantially constant intensity Intermittently at a predetermined cycle;
- a filtering means for selectively receiving a component of light emitted from a light emitting position, which component has a wavelength corresponding to a fluorescent light;
- a photoelectric converting means for converting the light, received through the filtering means, into an electric signal;
- a waveform shaping means for inverting and amplifying half of an output signal from the photoelectric converting means in synchronism with a timing displaced 90° from an irradiating period of the light irradiating means;
- a low-pass filtering means for selectively extracting a direct current component from an output from the waveform shaping means;
- and
- a comparing means for comparing a detected voltage outputted from the low-pass filtering means with a predetermined voltage and for outputting a detection signal in the event that the detected voltage exceeds the predetermined voltage.
An optical reading apparatus which comprises:
- a projecting unit for projecting an exciting light necessary to excite a fluorescent substance onto a carrier formed with a fluorescent mark containing the fluorescent substance;
- a light receiving unit for receiving a fluorescent light emitted from the fluorescent substance and light reflected from the carrier and converting them into an electric signal;
- an amplifying unit for amplifying the electric signal outputted from the light receiving unit;
- and
- a signal detecting unit for detecting information recorded by the fluorescent mark from an output signal from the amplifying unit,
- characterized in that the amplifying unit has an amplification factor which is variable according to the intensity of the reflected light incident on the light receiving unit and in that the output signal from the amplifying unit which has a peak value lower than a predetermined value is supplied to the signal detecting unit for analog-to-digital conversion thereof to provide a digital signal corresponding to a pattern in which the fluorescent mark is formed.
An optical reading apparatus which comprises:
- a projecting unit for projecting an exciting light necessary to excite a fluorescent substance onto a carrier formed with a fluorescent mark containing the fluorescent substance;
- a light receiving unit for receiving a fluorescent light emitted from the fluorescent substance and light reflected from the carrier and converting them into an electric signal;
- an amplifying unit for amplifying the electric signal outputted from the light receiving unit;
- and
- a signal detecting unit for detecting information recorded by the fluorescent mark from an output signal from the amplifying unit;
- characterized in that the amplifying unit has an amplification factor which is variable according to the intensity of the reflected light incident on the light receiving unit and the intensity of the fluorescent light and in that the output signal from the amplifying unit which has a peak value lower than a predetermined value is supplied to the signal detecting unit for analog-to-digital conversion thereof to provide a digital signal corresponding to a pattern in which the fluorescent mark is formed.
An optical reading apparatus which comprises:
- a projecting unit for projecting an exciting light necessary to excite a fluorescent substance onto a carrier formed with a fluorescent mark containing the fluorescent substance;
- a light receiving unit for receiving a fluorescent light emitted from the fluorescent substance and light reflected from the carrier and converting them into an electric signal;
- an amplifying unit for amplifying the electric signal outputted from the light receiving unit;
- and
- a signal detecting unit for detecting information recorded by the fluorescent mark from an output signal from the amplifying unit;
- characterized in that the output signal from the amplifying unit is supplied to the signal detecting unit so that the output signal from the amplifying means can be sliced in the signal detecting unit by two or more slice signals having two or more slice levels to provide two or more digital signals whereby a digital signal corresponding to the fluorescent mark can be obtained by logically summing the two or more digital signals together.
An optical reading apparatus which comprises;
- a projecting unit for projecting an exciting light necessary to excite a fluorescent substance onto a carrier formed with a fluorescent mark containing the fluorescent substance;
- a light receiving unit for receiving a fluorescent light emitted from the fluorescent substance and light reflected from the carrier and converting them into an electric signal;
- an amplifying unit for amplifying the electric signal outputted from the light receiving unit;
- and
- a signal detecting unit for detecting information recorded by the fluorescent mark from an output signal from the amplifying unit;
- characterized in that an output signal outputted from the amplifying unit when an amplification factor thereof is set to a low value and an output signal outputted from the amplifying unit when the amplification factor thereof is set to a high value are supplied to the signal detecting unit so that the output signals from the amplifying means can be sliced in the signal detecting unit by a slice signal having a particular slice level to provide two or more digital signals whereby a digital signal corresponding to the fluorescent mark can be obtained by logically summing the two or more digital signals together.
Dependencies are inferred from the claim text.