JPS5970929A - Apparatus for detecting color - Google Patents

Abstract

PURPOSE:To reduce the number of photoelectric converters as compared with the number of colors of inks, by a method wherein a color material carrier is irradiated with two light sources and the lights thereof are respectively received by the photoelectric converter having spectroscopic sensitivity characteristics almost the same to the sight sensitivity of a human being to perform color discrimination. CONSTITUTION:A first red light source and a second green light source 23 are parallelly placed on the ink coated surface of an ink carrier 21 so as to provide the distance (l) therebetween. A first and a second photodiodes 24, 25 are respectively placed in opposed relation to the first and the second light sources 22, 23 so as to leave the distance (l) therebetween in the direction vertical to the ink coated surface of the ink carrier 21. When lights are received by the first and the second photodiodes 24, 25, minute currents are flowed and, therefore, treated by a first and a second treating parts 26a, 26b. By the combination of the outputs from these treating parts, an ink color is judged by a judging part 26c and LED having a color the same to the ink color is emitted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a color detection device for detecting the color of ink on an ink carrier coated with inks of different colors.

[Technical background of the invention and its problems]

As a thermal transfer recording device (d), there is a color recording device using a field sequential method, as shown in Japanese Patent Application No. 22144/1983.

As shown in Figure 1, this field-sequential system is capable of repeatedly applying three colors of ink, magenta, cyan, and yellow, over an area that is approximately 7.1 times larger than the effective recording area (for example, A4 size). For the ink carrier (former ink carrier), a heating resistor array (12) having the same length as the width of this ink carrier (11)
The ink is transferred onto recording paper (13i) and recorded.

To explain in more detail, the fourth format recording is performed for one color of ink on the ink carrier (flu), the ink carrier (11) is advanced in inch to the area where the next ink is applied, and at the same time the recording paper (131 is the recording paper). Return to the starting point.

Then, the next ink is transferred over the area recorded with the - color ink. In this way, recording is performed using three colors of ink, and one sheet of color recording is completed.

In this device, the ink on the ink carrier 0'1J is provided over a fixed area in the longitudinal direction of the ink carrier aυ, but at the boundary of the patterns, overlapping patterns or gaps occur due to manufacturing reasons, and the ink is It is difficult to accurately maintain the repeat pitch of the pattern.

Therefore, for example, if you cue up to the ink area of the next color by advancing a certain distance after completing printing for the effective printing area for the - color, an error will occur.
As printing progresses, printing may be performed using an ink area different from the predetermined color. Ink IF! solves these problems. As many color detection devices as the number of ink colors installed in the old ink were installed, and color detection was performed using a set of color detection devices consisting of one light source and one photoelectric converter for each color. It has been proposed to control the transport of the ink carrier 0υ based on the detection signal. But a large number of color detection devices? However, the space occupied by these devices hinders miniaturization of the recording device and is disadvantageous in terms of cost.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks and provide a color detection device that can detect and discriminate ink colors on an ink carrier using fewer light source converters than the total number of ink colors.

[Summary of the invention]

With this invention, the first method is to identify the peaks of different emission wavelengths.
The light from the first and second light sources is received through the ink carrier (-) by a photoelectric converter 112 provided correspondingly to each other, and the combination of the output signals of the light converters is used to detect the ink phase. It is characterized by detecting the color of ink.

(・Well, the spectral sensitivity characteristics of the photoelectric converter are approximately fi
t at a wavelength of U O,1+n (4 degrees is the highest, 70
It is preferable that the sensitivity be almost zero at wavelengths of 01 m or more and 400 nm or less.

As the light source for the first light 'j'K Th, ~)2, it is preferable to use a light source whose emission wavelength has a peak M near about 560 nm1. Approximately 700n for tli-1 and 17
It is also preferable to use a light source having an emission wavelength peak around 590 nm as the second light source.

〔Effect of the invention〕

According to this invention, at least three ink colors can be distinguished using two light sources, and the configuration is simple.

[Detailed explanation of the invention]

Next, a preferred embodiment of this arrangement will be described with reference to the drawings.

As shown in FIG.
and the second light source 12, (c), the first and second photodiodes +2-6, t2ω, and the first and second photodiodes.
photodiode +241, and a signal processing unit f21i) that detects color based on the signal from rB.

The first and second light sources 1.13) and L'3) are L marks (Ligl+tErr+1ssin L) iode). The first light source (a is a red light source, TLR103 manufactured by Tokyo Shibaura Electric Co., Ltd.).
) is a green light source, TLG 103 manufactured by the same company. first and second photodiodes +24), f2
5) are both Silliman planar photodiodes made by the same company, and are '1'' PS701.

First and second photodimates 1. ! 41, +2
The spectral sensitivity characteristic of 5+ is approximately 56 as shown in Figure 3.
It is characterized by the highest sensitivity to wavelengths of 0 nm and nearly zero sensitivity to wavelengths of 700 nm or more. This characteristic approximately matches human visual perception.

The shapes of the curves also almost match.

First light source c! As shown in FIG. 4, the emission wavelength characteristics of iron are characterized by a strong intensity at a wavelength of about 700 nm. Regarding the directional characteristics, as shown in Fig. 3, the intensity is halved at θ=230, and at θ=45°, the intensity becomes 0.2, indicating strong directivity.

As shown in FIG. 6, the emission wavelength characteristics of the second light source (second order) have the maximum intensity at a wavelength around about 565 nm.

As can be seen from the directional characteristics shown in FIG. 7, the directivity is strong.

Such first and second light sources 173, [23 are
placed parallel to the ink application surface of the ink carrier (2υ) with a distance l; these first and second light sources +23;
f2. For each of J, a first and a second photodiode r, J41, l'/! with a distance l in the direction perpendicular to the ink-applied surface of the ink carrier (2I). 5) is placed. In this example l=5 mm.

As can be seen from FIGS. 5 and 7, the first and second light sources 123, (9th floor each have strong directivity,
The intensity of light heading in the direction of θ=45° is very small. Therefore, the photodiode C24° (29°) in this example
receives only light from the corresponding light sources f23 and ρ.

Next is the signal processing section! 7 (9 will be explained. This signal processing unit) is the first and second photodiode 124)
.

(2; first and second processing units (26a) corresponding to
(26b). First and second processing units (26a)
, (26b) have the same structure, and the first processing unit (
26a) will be specifically explained in accordance with FIG. The first processing section (26a) here is roughly the first processing section (26a).
to third integrated circuit 1・+11, fl(II, 1
8: Consists of →. First and second integrated circuits ()Il
l, +83 is Tokyo Shibaura Electric Co., Ltd.) Eye 1'A
7505M and is an operational amplifier. The third integrated circuit 1831 is a TA7521P manufactured by the same company and is a comparator.

The first integrated circuit (81) includes a first photodiode 1
The change in small current from 2a is converted into a change in pressure.

t■τ2 integrated circuit (821 is the first integrated circuit (81
Convert the voltage of the signal from 1 to an appropriate value. l;! 43
For integrated circuits, this is a comparator that compares the basic pressure with +.

Now, '1'' A7505, which is the integrated circuit member υ of 81!1.
The second pin of M is connected to the anode of the first photodiode +241, a first resistor (84) having a resistance value IMΩ, and one end of a capacitor (to) having a capacitance of zo, o1sμF. One end of a second resistor [F]6) having a resistance value of IMΩ is connected to the third bin. A variable resistor v(1 is connected between the first pin and the fifth pin.
The pin is grounded.

The seventh bin is supplied with +5■ as Vcc. The sixth pin is used as an output terminal.

6th pin, other terminal of the first resistor (goods), capacitor Ql
The other terminal of lω is a third resistor with a resistance value of 18Ω.
Connected to one end of the barrel. The other end of the third resistor (c) and one end of the variable resistor (89) are connected to the second pin of the second integrated circuit. A fourth resistor (one end of 11υ is connected to the third bin, whose resistance value is 100Ω.
The pin is grounded. The 7th bin has +5v as Vcc.
is supplied. The 6th pin is used as an output terminal.

The other end of the variable resistor, the sixth pin, is connected to one end of a resistor f911 made of paulownia wood 5 and having a resistance value of 100Ω. The other end of the fifth resistor (91) is connected to the seventh bin of the third integrated circuit (c). Both the third and twelfth bins are grounded. +5v is supplied to the 14th pin as Vcc.

The sixth pin has the sixth and seventh resistors (!ld, (93
One end of 1 is connected. The resistance value of the 6th resistance country is 56Ω, and the resistance of the 7th floor (the resistance value of the 9th floor is 470Ω.
The other end of the resistor 94 is connected to the variable terminal of the variable resistor 014. One end of a 21m1 constant wire with a variable resistor (!1.υ) is grounded. +5V is supplied to the other end of the fixed terminal.

The other end of the resistor shown in FIG. 7 is connected to the fourth pin. The second pin becomes the output terminal.

The cathode of the photodiode (2) of silk 1, the other end of the second resistor (86), the fourth resistor; 'A61. +5V is supplied to the other end of the eighth resistor (95). eighth and ninth resistors t',
The resistance values of 61 and t:Na are both 1.2 and Ω.

Also, variable resistance +q'il, 1M! l) , (!l
・υ acid dog IE (anti-value is 10■(Ω, 500)
Ω and IKΩ.

Next, the operation will be explained. First photodiode 1
When Oka receives light from the first light source 1, a minute current flows in the forward direction. This minute tb current is amplified by the first integrated circuit (8υ).It is amplified by this integrated circuit Sυ.The second pin of this electroplating circuit (81) is an inverting input terminal; No resistor is connected to the side, and the first resistor Q: 50 is connected to the feedback route side.
is provided. Therefore, the amplification factor of the amplifier using this integrated circuit (81) is theoretically infinite, and there is a possibility of oscillation. To prevent this, Conodenza (“(5
) is provided. The variable resistor (80 is for offset adjustment.

However, the output signal of this first integrated circuit (8I) is
It will never be infinite, but will be a certain value. This value is also not suitable for signal processing and is set to a suitable value by the second integrated circuit (82).

This value becomes the GW"f function by adjusting the resistance value of the variable resistor (6!1). Cyan, magenta, itp↓
These are shown in the columns of light source R and light source G in Table 1.

In Table 1, such an output is input to the third bin of the third integrated circuit, and the reference voltage is input to the sixth pin.

This reference '4 pressure is set by dividing the resistance value of the variable resistor (!+4) by d. In this example, this criterion sets the pressure to the first. Second process j4! All four parts are set to 3v.

Compare the output signal of the second integrated circuit (4) shown in Table 1 with the dark value of 3 V at the peak of 1.1? and the third integrated circuit of the second processing section. When signal II III is small, No. 43 t+ Or+
is output, and the results are shown in Table 12.

The column of light source rGJ corresponds to the output from the second processing section (26b).

In the enactment part (26c), such '1) 41 and the second
The first . No. 43 of the second treatment Lμ is both II
If O#, the ink color is cyan, and the first processing unit output is I
I III, if the output of the second processing section is °'0''', the ink color is magenta], and if the output of the processing section of ff12 is both It III, the ink color is determined to be yellow. Consists of a logic circuit like the 9th V R-G
When JJ = 1, yellow LED (PL) 1), when R and G = 1, red LlD (PD2), and when R and G = 1, blue LED (1) I) 3), and so on. This circuit causes an LED of a similar color to the ink color to emit light, and outputs 1 (High 1 level) only to the output terminal corresponding to the ink color and 0 to the other terminals.

[Other embodiments of the invention]

Next, an example using a yellow LED as a light source will be described.

As shown in FIG. 10, the light source (101) and this light source (
A photodiode (102) is arranged with respect to the ink carrier C2I) via the ink carrier C2I), and a signal section (103) that determines the color of the ink on the ink carrier 0υ based on the signal of this photodiode (LO2>). Consists of.

The signal processing section (013) is a photodiode (102)
i+ for all output signal processing? + A processing section (104) that converts into a signal having a pressure of 1 (+4
) to compare the signal from the first . Second. It consists of comparison circuits (105), (106), and (107) of Fake 3.

BU0dnecl:g) is Tokyo Shibaura Kaiki Co., Ltd. 4L'4
OLE, D, and TLY103. This light source (
1,02) is shown in the diagram. Similarly, its directivity characteristics are shown in FIG.

The photodiode (102) is the same as in the previous embodiment. The processing unit (104) includes the integrated circuits 1 and 2 of the first and second ladle shown in FIG. The output from the sixth bin of the second integrated circuit (32) is shown at (14j) of rYJ in the first circuit.

Such an output signal is used as the first. Second. Third comparison circuit (1
05), (106), and (107), three thresholds, namely 1. OV, 2.5V, 3.7V
Compare with. These comparison circuits (+05), (106)
, (107) is [signal Ll if larger than 4J value
, II, otherwise outputs °゛0''.

Then, 1. Second. Third comparison circuit (1,05).

The signals from (106) and (107) are as shown in Table 3.

Figure 4 As can be seen from Table 4, the first. Second. The color of the ink and the presence or absence of the ink on the ink carrier Qυ can be determined by the combination of the outputs of the third comparison circuits (105), (106), and (107).

[Other embodiments of the invention]

Next, an example will be shown in which red and blue LEDs are used as light sources.

The configuration is the same as the first embodiment (FIG. 2). A red Lm is used as the first light source Q, and a blue LED is used as the second light source 23. The ink carrier (21) used is one coated with ink of three colors: black, cyan, and magenta. By setting appropriate reference voltages for the third integrated circuits (c) of the first and second processing units, the output signals of the third integrated circuits shown in Table 4 were obtained.

By combining Table 5 ηz1 and the output signal of the second processing section, as is clear from Table 5, black, cyan,
Each magenta color ink could be identified.

If the color of the ink on the ink carrier (21) can be identified in this way, the field sequential type thermal transfer recording apparatus can be operated as follows.

For example, as shown in FIG. 13, a field-sequential thermal transfer recording device includes a thermal head (132) including a heating resistor (131), and a platen roller provided opposite to the heating resistor array (131). (133) and a heating resistor (1
31) and a platen roller (133), and consists of an ink carrier (134) that is conveyed only in one direction, and a recording paper (135) that is conveyed in a reciprocating direction.

The recording paper (135) is placed between guide rows 2 (136) and (13).
7) makes it run along the platen roller (133).

The ink carrier (134) is pressed onto the platen roller (133) near the heating resistor (131) via the recording paper (135) by an inlet pressure roller (138). Further, an outlet pressure roller (139) is provided on the opposite side of the inlet pressure roller (128), and the print carrier (134) is placed on the recording paper (135) at a position different from the ink transfer position.
It is peeling off from.

The aforementioned color detection device, that is, a light source (141), a photodiode (142), and a signal processing device (not shown) are provided between the ink carrier supply section (140) and the heating resistor (131).

In such a thermal transfer recording device, during recording, a thermal head (132) carries an ink carrier (134) and a recording paper (
135) Bring the platen roller (133) into pressure contact.

In this state, recording signals corresponding to each single color are supplied to the heating resistor (131) one color at a time, corresponding to the effective recording area. When recording for one color is completed, a part of the ink applied surface of the first color ink area (143) on the ink carrier (135) becomes an ink drop area (144) as shown in FIG. 4. Normally, recording is done so that some unused portion remains. This means that the alignment between the ink carrier (134) and the recording paper (135) in this embodiment is at least several tens of degrees.
This is because although it has been achieved on the order of microns, the accuracy of ink distribution cannot be improved to that extent.

Therefore, at the time when recording of the first color is completed, the row-shaped heating resistors (131) are in the ink area (143) of the first color.
) is located at the location indicated by the arrow (145) in Fig. 14 above.

Naturally, the recording of the second color is not done from this position,
A heating resistor (1:3) is placed in the second color ink area (146).
It is necessary to start from the position where 1) is in contact.

In this example, the light source (141
) and a photodimate (142) to detect the color of the ink on the ink carrier (134). This detection position is preferably performed at a fixed ink transfer position.1. However, it is structurally resistant to bacteria, and the color is normally detected at a different position from the ink transfer position.

However, the light source (141) and the photo 1 installed facing each other
．． If the distance between the position of the diode (142) and the heating resistor (131) of the thermal head is set accurately, the ink carrier (134) will be detected by the color detection signal from the color detection device.
By feeding the ink by a predetermined feeding amount l, it is possible to accurately locate the beginning of the ink.

The conditions imposed on the feeding amount l of the ink carrier (134) are as follows:
Even if the heating resistor (131) still contacts the next ink area and the next color is recorded, the heating resistor (131)
The two points are that the ink remains in the ink area of the same color. Moreover, as shown in FIG. 15, instead of detecting transmitted light as in FIG. 2, a first light source (151), a second light source (152), and a first photodiode (153) )
, and the second photodiode (154) may all be arranged on the ink application side of the ink carrier (2υ).In this case, the light source reflected from the ink surface of the ink carrier (2υ) The light is received and detected by a light-dense photodiode from 141-1, and the same numbers as in Fig. 2 indicate the same parts as in Fig. 2. In the case of the configuration shown in Fig. 14, the incident light and Light source so that the angle of reflected light is approximately 45°,
] By arranging i+ diodes, colors can be detected efficiently.

This arrangement is effective when the film base of the ink carrier (2I) is thick or the ink is opaque, and color discrimination was clearly obtained as in the embodiment shown in FIG. 2.

Furthermore, although the actual/IQ example is constructed using three stages of integrated circuits, it may be replaced by a two-stage circuit as shown in FIG. To explain this example, 1 is the current flowing through the photodiode PD in the pressure-down conversion amplifier circuit, R1 is the feedback resistor of the operational amplifier, and R is the volume R that determines the bias voltage.
When the voltage of v is VB, the output IL voltage V of the operational amplifier is V=V(, -iR+. 2 is a sicomit trigger circuit using a comparator, and the 17th
Logic output voltage V as shown. [High level of T is 5
By configuring the circuit so that the port low level is 0 volts, it operates stably even against noise and vibrations in the photodetection system, and has no chattering.
You can get the number.

Furthermore, since the color of the ink on the ink carrier can be detected, it goes without saying that the ink film can be transported to any color.

Although the embodiments have been described using specific light sources and photodiodes, the invention is not limited thereto, and it goes without saying that any light source or photodiode can be selected within the scope of the claims.

Although the embodiments have been described using a thermal transfer type color recording device, it goes without saying that the present invention can also be suitably used in a recording device that uses an ink carrier in which a plurality of color materials are disposed on the carrier.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an overview of a thermal transfer recording device, FIG. 2 is a schematic diagram showing a color detection device according to an embodiment, and FIG. 3 is a configuration of the color detection device shown in FIG. 2. The spectral sensitivity IW characteristic diagram of the photodiode, Figures 4 to 7 are diagrams showing the characteristics of the light source that constitutes the device, and Figure 8 is a circuit diagram of the signal processing section that constitutes the device, h) 9 The figure is a circuit diagram showing one part, and Figures 10 to 12 show other embodiments of the color detection device 7, and show a color thermal transfer recording device using the color detection device.
Figure 14 does not show the ink carrier.
The figure shows another embodiment, and FIGS. 16 and 17 show other embodiments of the processing section. Ink carrier...11, 21, light source...22, 23, 9
1°131, 141, 142, photo die code...24, 25. ! 12, 143, 144, signal processing unit... 26° 6th
Figure 7゜'' 4i (ga Jη) Figure 8 Figure 9 Figure 16 Figure 17 Figure 10 Figure 11 Figure 12

Claims (1)

[Claims] (1) a first light source that emits red light that irradiates the coloring material carrier;
a second light source that emits green light; a second light source that emits green light;
A photoelectric converter having a spectral sensitivity characteristic that is approximately the same as human visual sensitivity, which receives light from a color material carrier of a light source, and a photoelectric converter having a spectral sensitivity characteristic that is approximately the same as the human visual sensitivity; A color detection device consisting of a signal processing section. Every visit. (3) Murakushi + - f: 1 Xie 44 name (, - Tan Hayate h℃
・ - 1hi and 1st H size - zuchi part horizontal H fraud degree → H body → ← Imi stirring phase 1 prostitution