JPH03182988A - Printed matter - Google Patents

Abstract

PURPOSE:To control an influence of a pattern, which is expressed with first and second materials under an information body, upon the quantity of fluorescence by approximating the quantity of fluorescence due to reflection on the first material and that on the second material to each other. CONSTITUTION:Not only characters 4 are printed on the surface of a base material 3 of a label 1 but also a bar code 5 as optical information is printed on these characters in ink including a fluorescent pigment or a fluorescent dye, and characters 4 are visually recognized under visible rays but the bar code 5 cannot be visually recognized. The quantity of fluorescence reflected by the base material 3 which is obtained in accordance with the reflection factor on the base material in the fluorescent wavelength area of fluorescent matters and the spectral characteristic of the fluorescence from fluorescent matters and that reflected by characters 4 which is obtained in accordance with the reflection factor on characters 4 in the fluorescent wavelength area of fluorescent matters and the spectral characteristic of the fluorescence from fluorescent matters are approximated to each other. Thus, the pattern expressed with the base material 3 and characters 4 hardly have an influence upon the quantity of fluorescence when the detected bar code 5 is read by an optical information reader.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printed matter having an information carrier that is invisible under visible light but distinguishable under light of a certain wavelength other than visible light.

[Conventional technology]

2. Description of the Related Art Conventionally, one method for recording information on information carriers such as barcodes that cannot be seen under visible light is a method using fluorescence. This uses a fluorescent material that emits light of a different wavelength when irradiated with light of a specific wavelength (for example, ultraviolet light).

[Problem to be solved by the invention]

However, the amount of fluorescence generated in this case varies greatly depending on the underlying pattern (printed material) of the paper (base material) on which the fluorescent substance is printed. This is because there is a difference in the reflectance of the base pattern at the fluorescence wavelength and the excitation light wavelength. This causes a problem that the reading rate of mechanical reading decreases or reading becomes impossible. Therefore, in order to perform mechanical reading, it may be possible to print on an area without a base pattern, but the printing position of the invisible barcode (information body) is limited. Furthermore, as disclosed in Japanese Patent Application Laid-open No. 55-37658, it has been proposed to print a base pattern using a material that is transparent at the wavelength of the irradiated light in a device that reads bar codes by reflecting irradiated light. Although,
It has been difficult to apply the above technique to those using fluorescence because the irradiation light wavelength and the fluorescence wavelength are different.

An object of the present invention is to provide a printed matter that does not easily affect the amount of fluorescence from the information carrier when the information carrier is read using fluorescence.

[Means to solve the problem]

The first invention has a printed body that expresses a pattern that is visible under visible light using at least a first material and a second material, and a fluorescent material that is not visible under visible light is formed on the printed body. In the printed matter having an information carrier, the first material is determined from the reflectance of the first material in the fluorescence wavelength range of the fluorescent material and the spectral characteristics of the fluorescence from the fluorescent material.
The amount of fluorescence due to reflection on the material, the amount of fluorescence due to reflection on the second material determined from the reflectance of the second material in the fluorescent wavelength range of the fluorescent substance, and the spectral characteristics of the fluorescence from the fluorescent substance. The gist is a printed matter that approximates the following.

The second invention has a printed body that expresses a pattern that is visible under visible light using at least a first material and a second material, and information that is formed by a fluorescent substance that is invisible under visible light on the printed body. In the printed matter having a body, the amount of fluorescence due to the excitation light reflected by the first material determined from the reflectance of the first material in the wavelength range of the excitation light of the fluorescent substance and the spectral characteristics of the excitation light, and the amount of fluorescence due to the excitation light reflected by the first material, and The gist thereof is a printed matter that approximates the amount of fluorescence caused by the excitation light reflected by the second material, which is determined from the reflectance of the second material in the excitation light wavelength range and the spectral characteristics of the excitation light. It is.

[Effect]

The printed matter according to the present invention is irradiated with excitation light when the information on the information carrier is read, and the information carrier emits fluorescence due to the excitation light. A part of this fluorescence is reflected by the first material and the second material of the printing body below the information body.

Here, in the first invention of the present application, since the amount of fluorescence due to reflection on the first material and the amount of fluorescence due to reflection on the second material are approximated, the amount of fluorescence due to reflection on the first material and the amount of fluorescence due to reflection on the second material are approximated. The pattern expressed by the second material is suppressed from appearing in the amount of fluorescence.

On the other hand, a part of the excitation light is also reflected by the first material and the second material of the printing body below the information body, and the information body emits fluorescence due to the reflected excitation light. Here, in the second invention of the present application, since the amount of fluorescence caused by the excitation light reflected by the first material and the amount of fluorescence caused by the excitation light reflected by the second material are approximated, the amount of fluorescence caused by the excitation light reflected by the second material is approximated. The pattern expressed by the first material and the second material appears in the amount of reflected excitation light, and is further suppressed from appearing in the amount of fluorescence.

〔Example〕

An embodiment embodying the present invention will be described below with reference to the drawings.

FIG. 3 shows the appearance of an optical information reading device 2 for reading information on a label 1 as a card-shaped printed matter.

FIG. 4 is a plan view of the label 1, and FIG. 5 is a partial cross section of the label 1. Characters 4 (rAJ, rBJ) are printed on the surface of the base material (paper) 3 of the label l, and a barcode (information carrier), which is optical information, is printed on it using ink containing fluorescent pigments or fluorescent dyes. ) 5 is printed. Character 4 is visible under visible light. Moreover, although the barcode 5 cannot be visually observed under visible light, only the barcode 5 emits light when it is irradiated with ultraviolet light during reading. The barcode printing ink uses a substance such as zinc oxide (chemical composition formula: ZnO1, emission color: blue-green, peak wavelength: 495 nm) that is excited by ultraviolet light with a wavelength of 365 nm.

At this time, the amount of fluorescence of the barcode 5 is as shown in FIG. Lf3, fluorescence Lf4 due to the reflected light of the excitation light Le on the surface of the base material 3, reflected light Lf5 of the fluorescence Lf4 on the surface of the base material 3, fluorescence Lf6 due to the reflected light of the excitation light Le at the character 4, the fluorescence It is estimated by the sum total of the reflected light Lf7 at the character 4 of Lf6. At this time, the amount of fluorescence of barcode 5 is
It is greatly influenced by the reflectance of the base material 3 or the characters 4. For example, when a white base material 3 and black letters 4 were used, the amount of fluorescence on the base material and on the letters was 20 times different in experiments.

Here, the amount of fluorescence If (Lf2.Lf5 in FIG. 5) due to fluorescence reflection on the base material 3 is the product of the amount of fluorescence If (λ) at each wavelength λ and the reflectance R1 (λ) at that wavelength λ. In other words, it is a value proportional to the area S1 of R1(λ)·If(λ) in FIG. 1, and Ifl=C1fR1(λ
)・If(λ)dλ. Similarly, the amount of fluorescence due to fluorescence reflection at character 4 is 1f2 (Lf3.Lf7 in Fig. 5).
) is a value proportional to the area S2 of R2(λ)·If(λ) in FIG. That is, If2=C1fR2(λ)・
It is expressed as If(λ)dλ.

In this embodiment, the reflectance of the base material 3 and the characters 4 are selected, that is, the type of the base material 3 and the type of character printing ink are selected so that the fluorescence amounts If1 and If2 are equal.

In addition, the amount of fluorescence If3 (fifth
In the figure, Lf4) is the reflectance R of the excitation light at each wavelength λ.
The product of 3(λ) and the excitation light intensity Ie is the reflected intensity of the excitation light, and the sum of the fluorescence intensity If(λ) due to the excitation light of each wavelength λ, that is, the value proportional to the area S3 in Fig. 2. ,
If3=C2fIf(λ)dλ. Similarly, the amount of fluorescence If4 due to the reflection of the excitation light at character 4 (in Fig. 5,
Lf6) is the reflectance R4(λ
) and the excitation light intensity Ie is the reflected intensity of the excitation light,
The total amount of fluorescence If(λ) due to the excitation light of each wavelength λ,
That is, the value is proportional to the area S4 in FIG. 2, and I f
4=c2fI f (λ)dλ.

In this embodiment, the reflectance of the base material 3 and the characters 4 are selected so that the fluorescence amounts If3 and If4 are equal, that is, the type of the base material 3 and the type of character printing ink are selected.

As shown in FIGS. 3 and 6, the case 6 of the reading device is formed into a box shape, and the front of the case 6 is provided with an insertion lower into which the label 1 is inserted.

Further, a cold cathode discharge tube (black light) 8 as an ultraviolet light source is disposed inside the case 6, and this cold cathode discharge tube 8 illuminates the barcode 5 of the label 1 with light having a center wavelength of 365 nm. Furthermore, a reflecting mirror 9 is disposed within the case 6, and this reflecting mirror 9 reflects the fluorescence from the barcode 5 of the label l in a specific direction. An imaging lens IO, an aperture member 11 having a flat slit perpendicular to the reading line, and an image sensor 12 as a light receiver are arranged in this order in the direction in which the light is reflected by the reflection mirror 9. Then, the reflected light from the reflection mirror 9 reaches the scanning line of the image sensor 12 through the imaging lens 10 and the aperture member 11, and an image of the barcode 5 is formed.

The image sensor 12 is a one-dimensional image sensor that has a function of converting a barcode image on its scanning line into an electrical signal through an electronic scanning operation.

Also, inside the case 6 are a light source drive circuit 13, a power supply circuit 14,
An electronic control circuit 15 is built in, and a cold cathode discharge tube 8 is driven by a light source drive circuit 13. Further, a switching power supply is used for the power supply circuit 14 , and a commercial power supply of AC 100 V is inputted through a power supply connector 16 to supply the voltage used by the electronic control circuit 15 and the light source drive circuit 13 . The electronic control circuit 15 includes a barcode reading circuit and an LE described later.
D19, LCD 18. It is composed of a drive circuit that drives the buzzer 17.

Further, a buzzer 17 is provided on the back side of the case 6, and the buzzer 17 notifies the user that the barcode 5 has been decoded. As shown in FIG. 3, an LCD 18 and an LED 9 are disposed on the front side of the case 6, and the LCD 1
8, the decoding result is displayed as 0, and the LED 19 lights up when the power switch is turned on.

FIG. 7 shows a circuit for reading barcodes in the electronic control circuit 15.

An amplifier circuit 20 is connected to the image sensor 12, and the amplifier circuit 20 amplifies discrete electrical signals from the image sensor 12 that receives a barcode image from the label l. The waveform shaping circuit 21 shapes the signal amplified by the amplifier circuit 20 into a continuous signal.

Furthermore, the binarization circuit 22 converts the continuous signal from the waveform shaping circuit 21 into a digital signal of a binarization level with a time width corresponding to the bar width of the bar code 5, and sends the digital signal to the microcomputer 23.

Clock generator 24 generates a reference clock and outputs it to scan synchronization circuit 25 . The scan synchronization circuit 25 outputs an image sensor drive signal to the sensor drive circuit 26 at a predetermined timing based on the reference clock. The sensor drive circuit 26 drives the image sensor 12 using the signal generated by the scan synchronization circuit 25. The microcomputer 23 performs predetermined processing on the digital signal input from the binarization circuit 221, decodes barcoded characters, converts them into a general-purpose code (for example, ASCII code), and sends the R8 to the external device 27. -232C.

When reading a barcode, the label 1 is irradiated with ultraviolet light from the cold cathode discharge tube 8, causing the barcode 5 to emit light. Then, an image of the barcode is imaged on the image sensor 12 via an optical system including a reflection mirror 9, an imaging lens 10, and an aperture member 11.

Then, the microcomputer 23 outputs a reset pulse φTGE generation command signal to the scan synchronization circuit 25, and the scan synchronization circuit 25 outputs the reset pulse φTGE to the sensor drive circuit 2.
6, and the charges accumulated in the image sensor 12 are reset.

Then, the microcomputer 23 issues a command to output the transfer pulse φT6, and the scan synchronization circuit 25 outputs the transfer pulse φTG to the sensor drive circuit 26. This transfer pulse φ76
After the output of , the signals from the image sensor 12 are sequentially output to the amplifier circuit 20 by the driving clocks φ1 and φ2. Next, the microcomputer 23
A binary signal from the digitizing circuit 22 is input, decoding processing is performed, and the decoding result is output to the external device 27.

In this example, in this example, the light reflected by the base material 3 is calculated from the reflectance R1 (λ) on the base material 3 in the fluorescence wavelength range of the fluorescent material and the spectral characteristic If (λ) of the fluorescence from the fluorescent material. The amount of fluorescence Ifl and the letter 4 (in the fluorescence wavelength range of the fluorescent substance)
The amount of fluorescence If2 reflected by the character 4, which was determined from the reflectance R,2(λ) of the printed material) and the spectral characteristic If(λ) of the fluorescence from the fluorescent substance, was approximated. Further, the amount of fluorescence If3 due to the excitation light reflected from the base material 3 determined from the reflectance R3(λ) at the base material 3 in the wavelength range of the excitation light of the fluorescent material and the spectral characteristic If(λ) of the excitation light, The amount of fluorescence If4 due to the excitation light reflected from the character 4 obtained from the reflectance R4 (λ) of the character 4 (printed material) in the excitation light wavelength range of the fluorescent substance and the spectral characteristic If (λ) of the excitation light is approximated. As a result, the barcode 5 (information body) is read by the optical information reading device 2.
When reading 3, the pattern represented by the base material 3 and the characters 4 is less likely to affect the amount of fluorescence detected by the image sensor 12.

In this example, paper (base material 3) and ink (character 4)
However, this may also be considered for the first ink and the second ink, or for the paper and the first ink and the second ink. It should be changed.

Note that this invention is not limited to the above embodiments,
For example, the sensitivity of the image sensor 12 may also be considered. That is, if the sensitivity of the image sensor 12 is P(λ), the outputs PI and P2 of the image sensor 12 due to the reflection of fluorescence from the base material 3 and the characters 4 are given by the following equations.

1 C1fR'l(λ)・If(λ)・P(λ)dλ2 C1fR2(λ)・If(λ)・P(λ)dλAlso, I4 due to the reflection of the excitation light on the base material 3 and the character 4 Output P3 of image sensor 12. P4 is given by the following equation.

3 C2fIf(λ)・P(λ)dλ 4 C2fIf(λ)・P(λ)dλ Therefore, this PI and P2 are approximated, and P3. P4 may be set to approximate.

〔Effect of the invention〕

As described in detail above, according to the present invention, when reading an information carrier using fluorescent material, an excellent effect is achieved in that the pattern expressed on the base of the fluorescent material is less likely to affect the amount of fluorescence.

[Brief explanation of drawings]

Figure 1 is a diagram for explaining the optical characteristics of the example, Figure 2 is a diagram for explaining the optical characteristics of the example.
The figures are diagrams for explaining the optical characteristics of the embodiment, Fig. 3 is a perspective view of the optical information reading device of the embodiment, Fig. 4 is a plan view of the label, and Fig. 5 is a partially enlarged cross section of the label. 6 is a perspective view showing the internal structure of the optical information reading device, and FIG. 7 is a diagram showing the electrical configuration of the optical information reading device. ■ is a label as a printed material, 3 is a base material, 4 is a character as a printed material, and 5 is a barcode as an information material.

Claims (1)

[Scope of Claims] 1. A printed body that has a pattern visible under visible light made of at least a first material and a second material, and a fluorescent material that is not visible under visible light on this printed body. In a printed matter having an information carrier made of a substance, the amount of fluorescence due to reflection at the first material determined from the reflectance of the first material in the fluorescence wavelength range of the fluorescent material and the spectral characteristics of the fluorescence from the fluorescent material; A printed material characterized by approximating the reflectance of the second material in the fluorescence wavelength range of the fluorescent material and the amount of fluorescence due to reflection on the second material, which is determined from the spectral characteristics of the fluorescence from the fluorescent material. . 2. A printed material that has a printed material that shows a pattern that is visible under visible light using at least a first material and a second material, and has an information carrier made of a fluorescent material that is not visible under visible light on the printed material. In, the amount of fluorescence due to the excitation light reflected by the first material, which is determined from the reflectance of the first material in the wavelength range of the excitation light of the fluorescent substance and the spectral characteristics of the excitation light, and the wavelength of the excitation light of the fluorescent substance. A printed matter characterized in that the amount of fluorescence due to excitation light reflected by the second material, which is determined from the reflectance of the second material in the area and the spectral characteristics of the excitation light, is approximated.