JPH09161002A - Multiple printing reading system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To multiply print much information in a small printing area by irradiating the printing area with excitation light of a wavelength inherent to ink, individually detecting emitted light from printing information through an optical filter and reading out the detected light with a reader. SOLUTION: By irradiating the printing area with excitation light from two light sources 3-2a, a light is emitted from the center of ink 3-1 and the light is made to pass through an optical filter 3-4a. Then, two other light sources 3-2b and another filter 3-4b are substituted for the light sources 3-2a and the filter 3-4a, the printing area is irradiated with excitation light from the light sources 3-2b and light is emitted from the center of ink 3-1 and passed through the filter 3-4b. Thus, the light sources and the optical filter are substituted in accordance with the sort of ink so that the light sources 3-2a and the optical filter 3-4a are used in the base of reading out information printed with ink A, and the light sources 3-2b and the optical filter 3-4b are used in the case of reading out information printed with ink B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiple printing system in which a bar code or the like is overprinted with different inks in one place, and more specifically, different excitation light characteristics and light emission that emits light by irradiating the excitation light. The present invention relates to a print-reading method that multiplex prints a bar code at the same place by using at least two kinds of inks having different optical characteristics and having different wavelengths.

[0002]

2. Description of the Related Art In the prior art, information such as a bar code or the like previously printed on a paper or other object with a special ink is used as a material property of the ink, that is, the difference in the amount of light between the irradiated light and the reflected light, or According to the difference in light intensity, a lot of information is read by a small print code. However, if the printing area is limited, it is not possible to print a large amount of information only with the above-described technique, so it is necessary to perform multiple printing and read each piece of information individually. An example of the above-mentioned multiple printing is, for example, Japanese Patent Laid-Open No. 1-21
There is a method, such as the "multiple printing barcode method" described in Japanese Patent No. 92485, that uses a difference in light reflectance by printing with reflective ink. That is, in the method described in the above publication, a reader having light sources of different wavelengths is prepared so that a plurality of barcodes can be read by different wavelengths of light, and the barcodes of different inks such as visible light are used. A barcode printed with ink that has absorption characteristics in the wavelength light range and transparency in the visible light range, and an ink that has absorption characteristics in the visible light range and is transparent in the wavelength range other than visible light The printed barcode is used for multiple printing so that a large amount of information can be read from each of the plurality of barcodes.

[0003]

However, in the conventional printing method such as the bar code as described above, the amount of information per unit area is limited, and the size of the object to be printed is limited to some extent. It is difficult to give a lot of information to things. Further, the above-mentioned JP-A-1-29248
In the reflection type ink as described in Japanese Patent No. 5 publication,
Since the incident light and the reflected light have the same wavelength, it is impossible to separate the incident light and the reflected light by using a filter that passes only a specific wavelength. Therefore, the S / N ratio (signal / noise ratio) should be set too large. I couldn't. An object of the present invention is to solve such a conventional problem, facilitate reading of a plurality of pieces of information printed in an overlapping manner, enable multiple printing of a large number of information in a small printing area, and increase the amount of information per unit area. It is to provide a multi-print reading method that can be performed.

[0004]

In order to achieve the above object, the multiplex printing and reading system of the present invention has a plurality of different excitation light characteristics and emission light characteristics (especially wavelengths) emitted by irradiation of the excitation light. Each of the plurality of print information printed by overlapping with the light emitting ink is irradiated with excitation light of a wavelength peculiar to the ink, and the light emitted from the print information is individually detected through the optical filter, and the reading device It is characterized by reading. Further, the ink for printing a plurality of pieces of print information is characterized by being selected from a particle type ink and a dye type ink. Further, the plurality of pieces of print information are also characterized in that they have the same content printed in a limited print area. In addition, multiple print information, such as encrypted information and decrypted information, or some disassembled information and other information, is information that cannot be decrypted unless all of them can be read. I am trying.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a plurality of types of ink having different excitation light characteristics (wavelength) and emission light characteristics (wavelength) are used, and the inks are combined to individually extract information. It becomes possible.
In that case, since the incident light and the reflected light can be separated by the filter used for reading, the S of the read signal is
The / N ratio can be increased, and as a result, information can be multiplexed even when the printing area is small, and the amount of information per unit area can be increased.

[0006]

【Example】

<First Embodiment> A first embodiment will be described below with reference to FIGS. 1, 2, 3, and 4. By the way, to read ink, as described in the conventional example, a reflective type that uses the difference in reflectance of light and a light of a certain wavelength (excitation light) are radiated to emit light of another wavelength. There is a light emitting type that reads by utilizing the fact that it emits light. In particular, among the light emitting inks, the ink excited by ultraviolet light or infrared light is called invisible ink. The invisible ink has a feature that it is not easily affected by the background and the pattern and does not cause discomfort to the user. In the present invention, the latter luminescent ink is mainly used.

FIG. 1 is a characteristic diagram of wavelength light intensity showing wavelengths of excitation light and emitted light of two types of light emitting inks A and B. For example, in the case of a barcode printed with fluorescent ink, when excitation light with a wavelength of approximately 350 nm (ultraviolet light) is applied to the barcode, visible light with a wavelength of approximately 590 nm is detected as emitted light, and information based on that is detected. Can be read. On the other hand, if the barcode is printed with stealth ink,
When the barcode is irradiated with excitation light having a wavelength of about 800 nm (infrared light), infrared light having a wavelength of 1000 nm is detected as emitted light, and information can be read based on the infrared light. In addition, fluorescent ink (ultraviolet excitation visible light emission ink) and stealth ink
(Infrared light emitting ink) is a kind of invisible ink as described above. Further, since infrared light generally has a characteristic that it is hardly affected by the base, it is extremely effective when used in the present invention.

FIG. 2 shows excitation light characteristics (wavelength) and emission light characteristics.
FIG. 6 is an operation diagram showing a relationship between two types of particle type inks (A particles and B particles) having different (wavelengths) and excitation light. In the figure, first, B particles are printed on the base, A particles are printed on them,
Irradiation light of wavelength a1 which is excitation light for A particles is irradiated from above, and then wavelength b1 which is excitation light for B particles is irradiated.
The irradiation light of is irradiated. First, the reaction of excitation light and irradiation light of wavelength a1 with respect to A particles will be described. As shown in FIG. 2, a part of the irradiation light a1 itself is reflected by the base. The other part of the irradiation light a1 hits the A particles of the ink and excites the ink to emit light of wavelength a2. The irradiation light is B
When it hits a particle, it is absorbed. On the contrary, this time, the reaction of the excitation light for the B particles and the irradiation light of the wavelength b1 is shown. Similar to the above, a part of the irradiation light b1 itself is reflected by the base. The other part of the irradiation light b1 hits the B particles of the ink and excites the ink to emit light of the wavelength b2. Further, when the irradiation light hits the A particles, they are absorbed.

FIG. 3 is a diagram showing an example of an apparatus configuration for reading double-printed ink in the present invention. In FIG. 3, reference numeral 3-1 is a double-printed light-emitting ink that is an object to be read, and a bar code or the like hit on a postal matter is actually considered. Also, 3-2a and 3-2b are
It is a light source for irradiating ink with excitation light. Here, first, by irradiating the excitation light from the two light sources 3-2a, the emission light is emitted from the center of the ink 3-1 and passed through the optical filter 3-4a. Next, as shown by the arrow, another two light sources 3-2b and another filter 3-4.
In place of b, the excitation light is emitted from these light sources 3-2b so that the emission light is emitted from the center of the ink 3-1 and passes through the optical filter 3-4b. 3-3
Is an optical lens for converging the emitted light (common to each ink). Further, the above 3-4a and 3-4b are A
An optical filter for allowing only the emitted light of ink and B ink to pass through and removing the reflected light of excitation light.
Is a slit. Thus, when reading the information printed with A ink, the light source of 3-2a and the optical filter of 3-4a are used, and when reading the information printed with B ink, the light source of 3-2b and 3 are used. -4b optical filter,
Replace the light source and optical filter according to the type of ink. The emitted light that has passed through the slit is converted into an electric signal by the photoelectric conversion unit 3-6. The electric signal is amplified and binarized by the signal amplification / binarization unit 3-7, recognized by the recognition unit 3-8, and outputs the decoding result.

FIG. 4 is a diagram showing the construction of an apparatus for reading multiple-printed ink according to another embodiment of the present invention. Basically, it is almost the same as the configuration of the reading device in FIG. 3, except that the device arrangement from the light source 4-2 to the photoelectric conversion unit 4-6 is such that different inks can be read simultaneously at the same time. Are installed in parallel, and the other configurations are the same. Reference numeral 4-1 indicates an object to be read in which different types of luminescent inks, A ink and B ink, are printed in multiple. Further, 4-2a is a light source for irradiating the excitation light of the A ink, and 4-2b is a light source for irradiating the excitation light of the B ink. 4-3a and 4
-3b is an optical lens for converging the emitted light, 4-4a and 4-4b are optical filters for passing only the emitted light, and removing the reflection of the excitation light.
-5a and 4-5b are slits. The emitted light that has passed through the slit is converted into an electric signal by the photoelectric conversion units 4-6a and 4-6b. The electric signal is amplified and binarized by the signal amplification / binarization unit 4-7, and then recognized by the recognition unit 4-8.
It is recognized by and outputs the decoding result. In this device, it is not necessary to replace the light source or the optical filter, but only the double-printed read object 4-1 needs to be moved relative to each other as shown by the arrow. In the description of the embodiments, two types of inks, which are light emitting particle type inks, have been described, but the generality is not lost even if there are many types of inks.

<Embodiment 2> Next, a case where multiple printing is performed using a light emitting particle type ink and a light emitting dye type ink will be described. FIG. 5 shows multiple printing of ink (luminescent particle type ink:
FIG. 9 is a state diagram of each ink with respect to irradiation in the case of double printing of ink A and luminescent dye type ink: ink C).
Regarding the state of the ink, (1) is a case where the luminescent dye type C ink is printed and then the luminescent particle type A ink is printed. In the case of (2), contrary to the case of (1), the luminescent particle type A ink is printed, and then the luminescent dye type C ink is printed. First, the reaction of the excitation light and the irradiation light of wavelength a1 with respect to the A particles in the state (1) will be described. Part of irradiation light a1
It is reflected on the ground. Some other irradiation light a1
Hits the A particles of the ink and excites the ink to generate a wavelength a2.
Emits light. Further, when the irradiation light a1 hits the C dye, it is transmitted through the C dye and reflected by the base.

On the contrary, this time, the reaction of the excitation light for the C dye and the irradiation light of the wavelength c1 will be described. Similar to the above, a part of the irradiation light c1 itself is reflected by the base. The other part of the irradiation light c1 hits the C dye of the ink to excite the ink and emit light of wavelength c2. Further, the irradiation light c1 is A
If it hits a particle, it will be absorbed. Next, the reaction of the excitation light and the irradiation light of wavelength a1 with respect to the A particles in the state (2) will be described. A part of the irradiation light a1 itself is reflected by the base. The other part of the irradiation light a1 hits the A particles of the ink to excite the ink and emit the light of the wavelength a2.
Although not shown in the figure, when the irradiation light a1 hits the C dye, the C dye is transmitted to hit the A particles to excite the ink to emit light of the wavelength a2, or Is reflected. On the contrary, this time, the reaction of the excitation light for the C dye and the irradiation light of the wavelength c1 is shown. Similar to the above, a part of the irradiation light c1 itself is reflected by the base. The other part of the irradiation light c1 hits the C dye of the ink to excite the ink and emit light of wavelength c2. Further, when the irradiation light c1 hits the A particles, it is absorbed by the A particles. Further, the apparatus configuration when reading the multiple-printed ink is the same as that of the first embodiment. In this description, one kind of light emitting particle type ink and one kind of light emitting dye type ink have been described, but the generality is not lost even if there are many kinds of ink.

<Embodiment 3> Next, a case of performing multiple printing using two types of luminescent dye type ink will be described. FIG.
FIG. 3 is a state diagram of ink and excitation light and emission light when ink is multi-printed (light-emitting dye type ink: double printing of D ink and E ink). First, according to FIG. 6 (1),
A case where the E ink is printed after the D ink is printed first will be described. When the light having the excitation light wavelength d1 of the D ink is irradiated, a part of the light d1 directly hits the base and is reflected. When it hits the D ink, it excites the D ink to emit light of wavelength d2. Further, when it hits the E ink, it passes through the E ink and excites the D ink to emit light of the wavelength d2, or it hits the base as it is and is reflected. Next, when the light of the excitation light wavelength e1 of the E ink is irradiated, as in the case of the irradiation of the light of the wavelength d1, a part of the light directly hits the base and is reflected. When it hits the D ink, it passes through the D ink and hits the base as it is and is reflected. When it hits the E ink, it excites the E ink to generate the wavelength e.
2 light is emitted.

Next, the case where the D ink is printed after the E ink is printed first will be described with reference to FIG. 6 (2). When the light of the excitation light wavelength e1 of the E ink is irradiated, a part of the light e1 directly hits the base and is reflected. When it hits the E ink, it excites the E ink to emit light of wavelength e2. Further, when it hits the D ink, the D ink is transmitted and the E ink is excited to emit the light of the wavelength e2, or it is directly reflected on the base. When the excitation light wavelength d1 of the D ink is irradiated, as in the case where the wavelength e1 light is irradiated,
Part of the light d1 directly strikes the base and is reflected. Also, E
If it hits the ink, it will pass through the E ink and hit the underlying substrate as it is to be reflected. When it hits the D ink, it excites the D ink to emit light of the wavelength d2. Therefore, which ink is printed first,
Double print reading is possible. Further, even when at least one ink does not transmit the excitation light of the other ink, if the printing order of the ink is fixed, double print reading becomes possible. For example, even if the D ink does not transmit the light of the wavelength e1, the D ink is printed first to enable double-print reading. In this description, two types of inks, which are light emitting dye type inks, have been described, but generality is not lost even when a plurality of types of inks are used.

<Fourth Embodiment> Next, a printing method capable of recording a large amount of information even when the printing area is limited will be described using the apparatus configurations of the first and second embodiments. FIG.
FIG. 9 is a diagram showing a printing example in which the same information is recorded with different inks to increase the recognition rate. First, in the printable area 7-3, if the information 7-1 that is the A ink is printed, and if the same information 7-2 is also printed with the B ink, it can be read out even in a limited area. Information can be printed on. In this case, either the information printed with the A ink or the B ink may be read. Therefore, even if one piece of information disappears due to a small area, it becomes recognizable information if the other piece of information can be read. Further, if the kind of ink is increased and the multiplicity of printing is increased, the recognition rate also increases.
Further, when both can be read, the matching check can be performed, and the reliability is improved, so that erroneous recognition can be prevented.

<Embodiment 5> Next, using the apparatus configuration of Embodiments 1 and 2, a printing method capable of increasing security by recording a large amount of information even when the printing area is limited is described. explain. FIG. 8 is an explanatory diagram of a method of separately printing encrypted information and a key for decrypting the information, as an example of the first printing method. For example, by printing confidential information such as a company secret using two types of invisible inks by the following printing method, information can be exchanged only between the parties without being known by a third party. For example, if the encrypted information 8-1 is printed with the A ink and the key information 8-2 for decrypting the code is printed with the B ink in the limited print area 8-3 on the paper, Even small print areas can be printed on top of each other. Even if one of them is read, only the key or the encrypted text does not serve as information, so that the leakage of confidential information can be prevented.

FIG. 9 is an explanatory diagram showing, as an example of the second printing method, a printing method in which one information is decomposed and separately recorded. For example, if a part of the decomposed information 9-1 is printed with the A ink and the remaining part 9-2 of the decomposed information is printed with the B ink in the limited print area 9-3, a small print area is obtained. But you can print them on top of each other. In this method as well, as in the previous printing method, even if one of them is read, the information is incomplete unless both are read, and it is possible to prevent leakage of confidential information.

[0018]

As is clear from the above description, according to the present invention, at least two kinds of ink having different excitation light characteristics (wavelength) and emission light characteristics (wavelength) are used, and a barcode is formed at one place. In the case of overlapping printing, since it is possible to individually read information with a large S / N ratio by each reading method, it is possible to multiplex information even with a small printing area and increase the amount of information per unit area. be able to.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of wavelength characteristics of excitation light and emitted light of two types of luminescent ink.

FIG. 2 is a principle diagram of a multiple printing method using two types of light emitting particle type inks.

FIG. 3 is a configuration diagram of a double-printing reader (light source / optical filter exchange type) showing an embodiment of the present invention.

FIG. 4 is a configuration diagram of a double-printing reading device (reading target moving type) according to another embodiment of the present invention.

FIG. 5 is a principle diagram of a multiple printing method using a light emitting particle type ink and a light emitting dye type ink.

FIG. 6 is a principle diagram of a multiple printing method using two types of luminescent dye type inks.

FIG. 7 is a diagram illustrating an example of a printing method in which the same information is recorded with different inks to increase the recognition rate.

FIG. 8 is a diagram showing an example of a printing method for decrypting information encrypted by using a key.

FIG. 9 is a diagram illustrating an example of a printing method in which information is decomposed, separately recorded, and decoded by combining.

[Explanation of symbols]

3-1 and 4-1: double-printed ink, 3-2a, 3-2b, 4-2a, 4-2b: light source, 3-3, 4-3a, 4-3b: lens, 3-4a 3-4b, 4-4a, 4-4b: optical filter, 3-5, 4-5a, 4-5b: slit, 3-6, 4-6a, 4-6b: photoelectric conversion unit, 3-7, 4-7: Signal amplification / binarization unit, 3-8, 4-
8: recognition unit, 7-1, 7-2: same information printed with different inks, 7-3: limited print area, 8-1: encrypted information, 8-
2: Decryption key, 8-3: Print area, 9-1: Decomposed information, 9-2: Remaining decomposed information, 9-3: Limited printing area.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Tetsuo Machida Tetsuo Machida 1 Ikegami, Haruoka-cho, Owariasahi-shi, Aichi Incorporated office system division, Hitachi, Ltd. (72) Tsunemi Oiwa 1-88, Tora, Ibaraki-shi, Osaka Within Hitachi Maxell, Ltd.

Claims (4)

[Claims] 1. An ink peculiar to the above-described ink, with respect to a plurality of print information printed by superimposing a plurality of light-emitting inks having different excitation light characteristics and emission light characteristics (especially wavelengths) emitted by irradiation of the excitation light. A printing reading method characterized in that excitation light of a wavelength is applied to each of them, and the emitted light from the printing information is individually detected via an optical filter and read by a reading device. 2. The ink for printing the plurality of print information,
The multi-print reading system according to claim 1, wherein the ink is selected from a particle type ink and a dye type ink. 3. The multiple print reading method according to claim 1, wherein the plurality of print information have the same content printed in a limited print area. 4. The plurality of pieces of print information are pieces of information such as encrypted information and decrypted information, or pieces of decomposed partial information and other pieces of information that cannot be decrypted unless all of them can be read. The multi-print reading system according to claim 1, wherein: