JPH0890886A - Ink ribbon detection device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a ribbon detection device for correctly detecting the position of an ink ribbon. [Structure] The light emitting element 5 emits white light. Due to this light emission, a spectrum of two predetermined wavelengths, which is transmitted through the ink ribbon 6 and attenuated according to the transmission characteristic peculiar to each ink color, is received.
It is incident on a and 7b. The light receiving elements 7a and 7b respectively convert incident light into currents, the voltage converters 8a and 8b convert these currents into voltage values, and the voltage values are compared with the comparator 9a.
And 9b respectively compare with preset comparison voltage values 10a and 10b, and output the comparison results as binary data. Thereby, a pair of binary data different for each ink color can be obtained, the color of the ink ribbon can be easily discriminated based on the pair of binary data, and the position of the ink ribbon can be easily detected from this. it can.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink ribbon detection device for detecting the color of an ink ribbon.

[0002]

2. Description of the Related Art Conventionally, printing on a thermal transfer recording apparatus has been
An ink ribbon in which ink is applied on a base film is used. This ink ribbon is in the form of a long strip having almost the same width as the recording paper.

In the case of an ink ribbon used for multicolor printing (color printing), a subtractive color mixture of Y (yellow: yellow), M (magenta: red dye), and C (cyan: greenish blue) is usually used. Ink of the three primary colors, or four colors of ink in which Bk (black: black) specially used for printing characters and the like is added to these three colors, which are repeatedly applied in sequence in the longitudinal direction on the base film. Ribbon is used. Then, these colors are mixed in various proportions by overcoating to express various shades and gradations.

In this multicolor printing, a detection device as shown in FIG. 8 or 9 is used to detect the color or position of the ink ribbon. In FIG. 8, a specific marking portion 2 is provided between the respective colors (ink colors a, b and c) formed on the ink ribbon 1, and when the ink ribbon 1 moves, printing is performed on the marking portion by the reflective photosensor 3. The color of the ink is discriminated by reading the various marks formed.

Further, in FIG. 9, a color set formed on the ink ribbon 1 '(ink colors a, b and c in the case of FIG. 9).
A specific marking portion 2'is provided between the three colors) and the initial position of a specific color (for example, ink color a) is determined by reading the mark with a reflective photosensor when the ink ribbon 1'moves. are doing.

Further, without using the marking as described above,
For example, as shown in Japanese Examined Patent Publication No. 2-59070, a method of directly determining a color by an optical sensor is also known.

[0007]

By the way, the method of making a specific marking between the colors shown in FIG. 8 has no meaning because the color cannot be discriminated by one kind of marking, so that three kinds of markings are always necessary. Become. For this reason,
On the one hand, when creating an ink ribbon, the management of matching the marking and the corresponding color is complicated, and on the other hand, when printing, the control of the sensor that determines the type of marking is troublesome. is there. Further, the method of marking between color sets shown in FIG. 9 is uneconomical because the color of the portion that has been fed in a waste until the detection of a specific head color is wasted, and is uneconomical. If the rewinding is performed up to this, on the one hand, the working time becomes long on the one hand, and on the other hand, control for rewinding is required, which again causes various problems.

Further, in addition to the above, in order to detect the color or position of the ink ribbon by using the marking as described above, in addition to the ink portion used for printing (printing), the marking is performed on the ink ribbon. Since the area used as a part is also required, the ink ribbon becomes longer, which causes a disadvantage of increasing the size of the ink ribbon cassette. Further, in producing the ink ribbon, there is also a problem that the step of adding a mark is added to the step of applying the ink, which increases the price of the ink ribbon.

The object of the present invention is to solve the above-mentioned conventional problems.
An object of the present invention is to provide an ink ribbon detection device that directly and correctly detects the color of the ink ribbon.

[0010]

The structure of the ink ribbon detection device according to the present invention will be described below. The ink ribbon detection device of the present invention receives a light emitting element that emits white light and a light emitted from the light emitting element through an ink ribbon having a plurality of colors, and has a first specific wavelength having a sensitivity wavelength. And the light emitted from the light emitting element through the ink ribbons having a plurality of colors.
Second light receiving element having a sensitivity wavelength at a second specific wavelength different from the second specific wavelength, first comparing means for comparing the output from the first light receiving element with a reference value, and the second light receiving element. It has a second comparing means for comparing the output from the element with a reference value, and a judging means for judging the color of the ink ribbon based on the outputs from the first comparing means and the second comparing means. Composed.

The first light receiving element and the second light receiving element are configured to receive light emitted from the light emitting element and transmitted through the ink ribbon, for example. Further, for example, as described in claim 3, it is configured to receive the light emitted from the light emitting element and reflected by the ink ribbon. Further, for example, as described in claim 4, the light emitted from the light emitting element is configured to be received via the ink ribbons having the colors of yellow, magenta, and cyan.

Further, for example, as described in claim 5, the first light receiving element is configured to have a sensitivity wavelength in green, and the second light receiving element is configured to have a sensitivity wavelength in red.

[0013]

In the ink ribbon detection device of the present invention, the white light emitted from the light emitting element is transmitted or reflected by the ink ribbon having a plurality of colors, for example, yellow, magenta and cyan. On the one hand, the first light receiving element is more sensitive to the first specific wavelength, for example green, and on the other hand the second light receiving element is changed to a second specific wavelength, for example red, different from the above green by receiving the transmitted or reflected light. It has a sensitivity wavelength. Judgment based on the output of the first comparing means for comparing the output from the first light receiving element with the reference value and the output of the second comparing means for comparing the output from the second light receiving element with the reference value. Means determine the color of the ink ribbon.

This makes it possible to correctly detect the color of the ink ribbon.

[0015]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of one embodiment. In the figure, the light emitting element 5 emits white light by being driven by a driver (not shown) controlled by a controller (not shown). The light emitted by this light emission passes through the ink ribbon 7, is attenuated according to the transmission characteristic peculiar to each color of the ink applied to the ink ribbon 6, and is attenuated according to the light receiving element 7a (first light receiving element) and the light receiving element 7b (first light receiving element). It is incident on the second light receiving element).

The light receiving element 7a is composed of, for example, a photodiode or the like, converts the incident transmitted light into a current, and outputs the converted current to the voltage converter 8a. Voltage converter 8a
Converts the current input from the light receiving element 7a into an analog voltage value and outputs this voltage value to the comparator 9a. Comparator 9
a compares the voltage value input from the voltage converter 8a with a preset reference value, that is, the comparison voltage value 10a, and outputs the comparison result as binary data to the determination circuit 11. The other light receiving element 7b, voltage converter 8b, and comparator 9
b and the comparison voltage value 10b are also the above-mentioned light receiving elements 7a,
It is configured similarly to the voltage converter 8a, the comparator 9a, and the comparison voltage value 10a.

The judgment circuit 11 is provided with the comparators 9a and 9b.
Based on the two binary data input from, the color determination of the ink ribbon described later in detail is performed, and the determination result is output to a predetermined circuit (not shown).

FIG. 2 shows the arrangement of the light emitting element 5, the ink ribbon 6, the light receiving element 7a, and the light receiving element 7b. In the figure, an ink ribbon 6 is composed of a transparent base film made of resin, an ink color a (for example, yellow Y),
The ink color b (e.g., magenta M) and the ink color c (e.g., cyan C) are repeatedly formed in a frame-sequential manner. The unused portion of the ink ribbon 6 is wound around the delivery core 6-1 and held, and is delivered from the delivery core 6-1 from the upper right to the lower left as indicated by an arrow A in the figure, and is driven by a drive mechanism (not shown). It is wound by the winding core 6-2 which is rotationally driven. A light emitting element 5 is arranged above the ink ribbon 6 and a light receiving element 7a and a light receiving element 7b are arranged below the ink ribbon 6. Of course, the light emitting element 5 may be disposed below and the two light receiving elements 7a and 7b may be disposed above.

By the way, the light transmittance of each of the ink colors a, b, and c of the ink ribbon 6 differs depending on the wavelength. FIG. 3 is a ribbon spectral transmission characteristic diagram of each color when an ink ribbon configured by three colors of yellow (Y), magenta (M), and cyan (C) is taken as an example. In the figure, the vertical axis shows the transmittance and the horizontal axis shows the wavelength of light in the visible region. As shown in the figure, yellow (Y)
Has a transmittance of about 20% at a wavelength of 400 to 440 nm (nanometer), and the transmittance sharply increases as the wavelength becomes longer up to 520 nm.
The transmittance of about 70% is maintained up to 0 nm. Magenta (M) has a transmittance of about 40% at a wavelength of 400 to 440 nm and about 5% at 520 to 570 nm of 630.
It is approximately 65% at ˜700 nm, showing a sharp fall and rise in the middle of these. And cyan (C)
Has a transmission characteristic of 40 at the lower part at 400 to 550 nm.
%, The sine curve with 70% of the vertices.
The transmittance drops sharply from 0 nm to 7 nm from 600 nm.
Almost 12% is maintained up to 00 nm.

Since the transmittance is different for each wavelength of light and for each color of ink in this way, if the transmitted light of the same wavelength is detected and converted into a voltage, a voltage value different for each color of ink is obtained. On the other hand, by detecting two lights (spectroscopy) having different wavelengths that have passed through the same ink color and converting them into a voltage, two different lights depending on the wavelength of the spectroscopy for one color can be obtained. The voltage value can be obtained. The light receiving elements 7a and 7b shown in FIG. 2 are provided to detect such a spectrum.

FIG. 4 shows the two light receiving elements 7a and 7b.
It is a figure which shows the spectral sensitivity characteristic of. In the figure, the spectral sensitivity characteristic of the light receiving element 7a is shown by a curve 12a, and the spectral sensitivity characteristic of the light receiving element 7b is shown by a curve 12b. As shown in the figure, the light-receiving element 7a has a spectral sensitivity characteristic that is sensitive to light (green) near the wavelength of 563 nm, while the light-receiving element 7b has a spectral sensitivity characteristic to light (red) near the wavelength of 685 nm. It has a sensitive spectral sensitivity characteristic.

A method for discriminating (determining) the color of the ink ribbon 6 in this embodiment having the above-described configuration will be described with reference to the charts shown in FIGS. 5 (a) and 5 (b). 5 (a), (b)
FIG. 6 is a chart showing a specific example in the case of performing color discrimination when there are three ink colors. The chart shown in Fig. 2 (a) has 2
Two different wavelengths of light of 563 nm (green) and light of 685 nm (red) which are respectively detected by the respective light receiving elements 7a and 7b are shown, and three kinds of inks are arranged on the ink ribbon 7 in the vertical direction in the left column. Colors, yellow (R), magenta (M), and cyan (C) are shown. In the column corresponding to these two kinds of wavelength light and the three kinds of ink colors, when white light is transmitted through these ink colors, the amount of transmitted light of the spectrum (green and red) of FIG. The voltage values output via the light receiving elements 7a and 7b and the voltage converters 8a and 8b are shown.

That is, in FIG. 3A, the voltage values obtained by transmission spectroscopy (green) at a wavelength of 563 nm are 3 for the ink colors yellow (R), magenta (M), and cyan (C), respectively.
It is shown to be 30 mV, 60 mV, 90 mV. These voltage values are the transmittances indicated by the intersections of the vertical broken lines 31 indicating the green wavelength region of the ribbon spectral transmission characteristic diagram of FIG. 3 and the respective curves Y, M and C, respectively, about 70%,
It is a voltage value corresponding to a light amount of about 5% and about 30%.

The voltage values obtained by transmission spectroscopy (red) at a wavelength of 685 nm are 1910 mV and 18% for ink colors yellow (R), magenta (M) and cyan (C), respectively.
It is shown to be 50 mV and 350 mV. These voltage values are also shown in the ribbon spectral transmission characteristic diagram of FIG. 3, and in this case, the vertical broken line 32 indicating the red wavelength region and the respective curves Y.
The transmittances indicated by the points where (1), M (2), and C (3) intersect are voltage values corresponding to the light amounts of about 68%, about 45%, and about 12%, respectively.

At this time, the comparison voltages 10a and 10b corresponding to the outputs from the voltage converters 8a and 8b.
If an appropriate comparison voltage (reference value) is set to, a pair of binarized data of two wavelengths of light corresponding to one ink color can be obtained from the outputs of the two comparators 9a and 9b.

For this, for example, with respect to the voltage value in the chart of FIG. 5 (a), 260 mV is set as the comparison voltage at the wavelength of 563 nm to the comparison voltage 10a, and the wavelength is 685 nm.
1100 mV as the comparison voltage when
Set to. The above comparison voltage 260 mV corresponds to the converted voltage value when the green transmittance of FIG. 3 is approximately 48% (see point 33 in FIG. 3), and the above 1100 mV is the red transmittance of FIG. This corresponds to the converted voltage value at 35% (see point 34 in FIG. 3). These points 33 and 34
Shows the point where any one of the three ink colors Y, M, and C is separated in the ribbon spectral transmission characteristic diagram of FIG.

As a result, the wavelength is 563 nm (green).
On the other hand, in the case of yellow (Y), the converted voltage 330 mV is higher than the comparison voltage 260 mV, so that “1” is output from the comparator 9a. Further, even for a wavelength of 650 mm (red), the conversion voltage of yellow (Y) is 1910 mV.
Is higher than the comparison voltage of 1100 mV, the comparator 9b
Outputs "1". Similarly, magenta (M)
In the case of, "0" and "1" are output, and in the case of cyan (C), "0" and "0" are output. As a result,
The binary data shown in the chart in (b) can be obtained. From this chart, if the output of the comparators 9a and 9b is "1, 1", the ink color is yellow (Y), if the output is "0, 1", it is magenta (M), and the output is " If it is "0, 0", it is easily found to be cyan (C).

Similar results can be obtained by using a light receiving element sensitive to a wavelength of 580 nm (yellow) instead of a light receiving element sensitive to a wavelength of 563 nm (green). Also, the same result can be obtained by using the reflection spectrum instead of the transmission spectrum.

The voltage value determined for each ink color corresponding to the different wavelength light shown in FIG. 5 (a) is determined by the light receiving elements 7a, 7a.
Depending on the characteristics of b or the circuit configuration of the voltage converters 8a and 8b, the values may be different from the values shown in the above chart, but even in that case, if the values are different from this chart, it will be different. In addition, the tendency of the strength and weakness corresponding to the wavelength and the color follows the tendency indicated by the ribbon spectral characteristic curve shown in FIG.
Similar results can be obtained by setting an appropriate reference value corresponding to that case.

Next, color determination in the case of four colors will be described. FIG. 6 (a) is a chart for explaining an algorithm for performing color determination of four colors. As shown in the figure, the two wavelength lights to be separated are shown in the upper column as the high wavelength hg and the low wavelength lw. These wavelengths are, for example, 500 for blue.
nm and red 685 nm. The four ink colors are shown in the left column vertically as ink color 1, ink color 2, ink color 3 and ink color 4. These colors are, for example, yellow (Y), cyan (C), magenta (M) and black (Bk).

FIG. 7 is a ribbon transmission characteristic curve diagram of the above four colors of yellow (Y), cyan (C), magenta (M) and black (Bk). This figure shows the ribbon transmission characteristic curve diagram shown in FIG. 3 with black (Bk) added. However, since black (Bk) does not transmit light at all, in the ribbon transmission characteristic diagram of FIG. 7, the ribbon transmission characteristic curve of black (Bk) is the same as the horizontal axis.

In the table of FIG. 6 (a), the light having two wavelengths hg and lw and the four types of ink color 1, ink color 2, ink color 3 and ink color 4 are shown in the corresponding columns. The voltage values output from the light-receiving elements 7a and 7b and the voltage converters 8a and 8b of FIG. 1 corresponding to the amounts of transmitted light of the ink colors are shown.
That is, at the wavelength hg, the voltage values due to the transmitted light are Va, Vb, Vc, and Vd for ink color 1, ink color 2, ink color 3, and ink color 4, respectively. These voltage values are, for example, in the ribbon spectral transmission characteristic diagram of FIG.
It is a voltage value corresponding to the transmittance indicated by the intersections of the characteristic curves yellow (Y), magenta (M), cyan (C), and black (Bk) that intersect the vertical solid lines 41 indicating the blue wavelength region.
In the figure, for reference, ink color 1, ink color 2, ink color 3, and ink color 4 are compared with, for example, yellow (Y), magenta (M), cyan (C), and black (Bk). For ease of explanation, a color symbol Y indicating a characteristic curve,
Color numbers 1, 2, 3, and 4 of the chart are shown in parentheses in M, C, and Bk, respectively.

As is clear from the ribbon transmission characteristic diagram of FIG. 5, if the voltage value corresponding to the point of the transmittance of about 35% in the 500 nm (blue) region (see point 42 in the figure) is the comparison voltage Vs, this 500 nm (blue) against Vs for comparison voltage
The transmitted light conversion voltages Va and Vb of Y (1) and C (2) are binarized to "1". In addition, V
M (3) and Bk with 500 nm (blue) for s
The transmitted light conversion voltages Vc and Vd of (4) are binarized to "0". The vertical middle column of the chart of FIG. 6 (b) shows the output of the comparator 9a of FIG. 1 in such a case.

Similarly, as is clear from the ribbon transmission characteristic diagram of FIG. 7, the transmittance in the 685 nm (red) region, that is, the voltage value corresponding to the point of about 35% (see point 34 in the figure) is used as the comparison voltage Vt. Then, the transmitted light conversion voltages Ve and Vg of Y (1) and M (3) by 685 nm (red) with respect to this comparison voltage are binarized to "1". Also,
This comparison voltage is C by 685 nm (red) with respect to Vt.
The transmitted light conversion voltages Vf and Vh of (2) and Bk (4) are binarized to "0". The vertical right column of the chart in Fig. 6 (b)
The output of the comparator 9b in FIG. 1 in such a case is shown.

As described above, by transmitting white light through any of the four ink colors and detecting the spectrum of the appropriate two wavelengths, as shown in the chart of FIG. 6 (b), a pair of different colors can be obtained. Binary data of can be obtained. As is apparent from FIG. 7B, if the outputs of the comparators 9a and 9b are "1, 1", the ink color is 1, if the outputs are "1, 0", the ink color is 2, and the output is "0, If it is "1", the ink color is 3, and the output is "0,
If it is "0", it is easily found to be ink color 4.
In this way, the colors of the ink ribbons can be easily discriminated even in the case of four colors. In this case, as in the case of the three colors, it is obvious that good results can be obtained by using the reflected light.

In this embodiment, the comparison voltage Vs set for the conversion voltages Va to Vd corresponding to the wavelength hg and the ink colors 1, 2, 3, and 4, the wavelength lw and the ink color 1, The comparison voltage Vt set for the conversion voltages Ve to Vh corresponding to 2, 3, and 4 is obtained from the following inequality.

Min (Va, Vb)>Vs> max (Vc, Vd) min (Ve, Vg)>Vt> max (Vf, Vh) The above “min” has two values Va, Vb (or Ve, V).
g), whichever takes the smaller value.
“Ax” indicates that the larger one of the two values Vc and Vd (or Vf and Vh) is taken.

In the case of three colors, if the inequality is Va>Vs> max (Vb, Vc) min (Ve, Vf)>Vt> Vg, the two wavelengths hg, lw to be selected at this time,
Corresponding to the comparison values Vs and Vt set for this,
The binary data of one to three pairs obtained from the outputs of the comparators 9a and 9b are “(1, 1), (0, 1), shown in FIG. 5 (b).
(0,0) ".

The inequality may be min (Va, Vb)>Vs> Vc min (Ve, Vg)>Vt> Vf. In this case, the binary data obtained from the outputs of the comparators 9a, 9b are , "(1,1), (1,0),
(0, 1) ". The binary data obtained from the outputs of the comparators 9a and 9b are converted into "(1, 0), (0, 1),
The inequality can be set to be (0, 0) ”.

In the above-described embodiment, the color discrimination is described by four colors, but the number of wavelengths sensitive to the light receiving element is appropriately increased without being limited to four colors, and the comparator can be changed accordingly. If the output of the comparator corresponding to each color composed of three or more binary data is obtained by increasing the number of positions, the position can be similarly detected even in the case of five or more ink colors.

[0041]

As described in detail above, according to the present invention, it is possible to obtain different binary data sets for each color by photoelectrically converting the transmission or reflection of the ink ribbon due to the different wavelength light. Therefore, it becomes easier to directly detect the color of the ink ribbon directly for each color, and therefore it is not necessary to additionally provide a detection mark or the like other than ink on the ink ribbon. Since the manufacturing process of the ink ribbon is also simplified, the cost is reduced, and in practical printing work, waste of time such as sending back the ink ribbon is eliminated and printing efficiency is improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an example.

FIG. 2 is a diagram showing an arrangement state of a light emitting element, an ink ribbon, and each light receiving element.

FIG. 3 is a ribbon spectral transmission characteristic diagram of each color when an ink ribbon formed of three colors of yellow (Y), magenta (M), and cyan (C) is taken as an example.

FIG. 4 is a diagram showing spectral sensitivity characteristics of two light receiving elements.

5A and 5B are charts showing a specific example in the case of performing color discrimination when there are three ink colors.

6 (a) and 6 (b) are charts for explaining an algorithm for performing color discrimination of four colors.

FIG. 7 is a ribbon transmission characteristic curve diagram of yellow (Y), cyan (C), magenta (M), and black (Bk).

FIG. 8 is a diagram (No. 1) for explaining a conventional method for discriminating the ink ribbon color.

FIG. 9 is a diagram (No. 2) for explaining the conventional method for discriminating the ink ribbon color.

[Explanation of symbols]

 1, 1'ink ribbon 2, 2'marking part 3 reflection type photo sensor 5 light emitting element 6 ink ribbon 6-1 sending core 6-2 winding core 7a, 7b light receiving element 8a, 8b voltage converter 9a, 9b comparator 10a, 10b Comparison voltage 11 Judgment circuit Y (1) Yellow spectral transmission characteristic curve M (2) Magenta spectral transmission characteristic curve C (3) Cyan spectral transmission characteristic curve Bk (4) Black spectral transmission characteristic curve 12a, 12b Spectral sensitivity characteristic curve of light receiving element

Claims (5)

[Claims] 1. A light emitting element which emits white light, and a first light receiving element which receives light emitted from the light emitting element through ink ribbons having a plurality of colors and has a sensitivity wavelength at a first specific wavelength. A second light receiving element that receives light emitted from the light emitting element through an ink ribbon having a plurality of colors and has a sensitivity wavelength at a second specific wavelength different from the first specific wavelength; First, comparing the output from the light receiving element of
And a second comparing means for comparing the output from the second light receiving element with a reference value.
And a judging means for judging the color of the ink ribbon based on the outputs from the first comparing means and the second comparing means. 2. The ink ribbon detection device according to claim 1, wherein the first light receiving element and the second light receiving element receive light emitted from the light emitting element and transmitted through the ink ribbon. . 3. The ink ribbon detection device according to claim 1, wherein the first light receiving element and the second light receiving element receive light emitted from the light emitting element and reflected by the ink ribbon. . 4. The first light receiving element and the second light receiving element convert the light emitted from the light emitting element into yellow,
The ink ribbon detection device according to claim 1, wherein the light is received through an ink ribbon having each color of magenta and cyan. 5. The ink according to claim 1, 2, 3, or 4, wherein the first light receiving element has a sensitivity wavelength in green and the second light receiving element has a sensitivity wavelength in red. Ribbon detection device.