JPH06198938A - Printing device - Google Patents

Abstract

PURPOSE:To contrive to realize a heat transferring type printing device, with which printed image having uniform density characteristics can be obtained at all times. CONSTITUTION:Ink ribbon is made so as to have nearly uniform reflectance by laser beam. Before the starting of printing, laser beam is irradiated over the ink ribbon under the condition that dye does not luminesce so as to detect the output level of the laser beam, which is best for the ink ribbon, and to start printing at the best output level. By monitoring the strength of the beam reflected from the ink ribbon with a PD 52 during printing and adjusting the output level of the laser beam so as not to change the strength of the reflected beam, the laser beam having the best output level is projected to the ink ribbon during printing at all times. Thus, a heat transferring type printing device, with which printed image having uniform density characteristics is obtained at all times.

Description

Detailed Description of the Invention

[0001]

[Table of Contents] The present invention will be described in the following order. Industrial Application Conventional Technology (FIGS. 7 and 8) Problem to be Solved by the Invention (7 and FIG. 8) Means for Solving the Problem (FIGS. 1 to 6) Operation (FIGS. 1 to 6) Embodiment (FIGS. 1 to 6) (1) Overall configuration (2) APC control of printer device (3) Operation of embodiment (4) Effect of embodiment (5) Effect of other embodiment

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer device, and is particularly suitable for application to a thermal transfer type printer device using a laser head.

[0003]

2. Description of the Related Art Conventionally, in a thermal transfer type printer device, an ink based on print data is printed on a print surface of a print paper by thermally transferring an ink such as a dye applied to one surface of an ink ribbon to a predetermined print paper. Those which are designed to be visually displayed and which are designed to directly transfer heat to the ink ribbon by using a thermal head, or laser light is applied to the ink ribbon by irradiating the laser light to the ink ribbon by using the laser head. There has been proposed one that is configured to generate transfer heat by converting (hereinafter referred to as photothermal conversion).

In this case, for example, in a thermal transfer type printer using a thermal head, the density of the image printed on the print paper (hereinafter referred to as the density of the image printed on the print paper depending on the amount of transfer heat stored in the thermal head which escapes from the ink ribbon to the thermal head). Is called the print density), so as a method to prevent this,
For example, a temperature correction circuit block 1 as shown in FIG. 7 is provided to output the output of the thermal head by the so-called APC (auto p
ower control) It is designed to control.

That is, in the temperature correction circuit block 1, the voltage conversion circuit 2 supplies the drive signal S2 of a predetermined voltage to the resistance element 5 of the thermal head 4 based on the power supply signal S1 supplied from the power supply block 3. At this time, the voltage conversion circuit 2 changes the voltage of the drive signal S2 based on the monitor signal S3 supplied from the thermistor 6 arranged in the thermal head 4 via the operational amplifier 7 so that the temperature of the resistance element 5 does not change. The predetermined printing density can be maintained by adjusting the amount of heat generated by the resistance element 5 in this way. In this case, as shown in FIG. 8, as the ink ribbon 10, a dye layer 12A made of each of yellow (Y), magenta (M), and cyan (C) dyes is provided on one surface of a transparent ribbon base 11.
12B and 12C and a black cord 13 for heading are sequentially formed are used, and color printing can be performed by sequentially thermally transferring the yellow, magenta and cyan dyes.

Similarly, in a thermal transfer type printer using a laser head, when a laser diode is used as an output source of laser light, the optical output characteristic of the laser diode is such that the optical output decreases as the temperature rises. The change in the optical output is large, and as a result, the intensity of the laser light output from the laser diode changes due to the temperature change, and the density of the print result changes. It is necessary to control the optical output level of the laser diode because it may be broken in a short time when oscillated with an optical output higher than the rated value. In practice, products using a laser diode (LD) such as compact discs and magneto-optical discs are subject to APC control, and in particular products using magneto-optical discs are used for optical output monitoring separately from the optical system. Is provided, and the output of the laser diode is APC controlled based on the output signal obtained from the photodiode.

[0007]

By the way, in a thermal transfer type printer apparatus using a laser head, laser light emitted from a light source is condensed and imaged using an optical system such as a lens, and then the ink ribbon is irradiated. Therefore, there is a problem that the printer device becomes large in order to increase the optical path length, and energy loss during printing due to reflection of laser light on the lens surface is large. For this reason, without using an optical system, for example, a light source (laser diode) is pressure-bonded to the ink ribbon via a protective cover glass or the like, and the laser light emitted from the light source is directly applied to the ink ribbon to diffuse the diffused light. If it is possible to convert light into heat, it is considered that the printer device can be downsized and the energy loss at the time of printing by the printer can be reduced.

Further, in this case, the printer device is provided with a photodiode for monitoring the optical output like the compact disc and the magneto-optical disc, and the optical output level of the laser diode is controlled based on the output signal output from the photodiode. If it is possible, it is considered that a printed image having uniform density characteristics can be obtained. However, in the thermal transfer printer having such a structure, it is difficult to install the photodiode for the optical output monitor separately from the optical system because of the structure, and the photodiode is integrated with the optical system to install the laser light from the ink ribbon. Even if the light output of the laser diode is controlled by using the reflected light (hereinafter referred to as return light), the return light changes sequentially according to the change in the relationship between the laser diode and the ink ribbon (for example, temperature). Therefore, there is a problem in that the monitor current output from the photodiode is not constant and accurate APC control is difficult.

The present invention has been made in consideration of the above points, and an object thereof is to propose a thermal transfer type printer device which can always obtain a printed image having uniform density characteristics.

[0010]

In order to solve the above problems, according to the present invention, in a thermal transfer type printer device 20 using a laser head 21, a predetermined code portion 40A is provided.
And / or an ink ribbon 33 having a substantially uniform reflectance with respect to the laser light over the entire surface except the mark portion, and a laser light irradiating means 51 for irradiating the ink ribbon 33 with the laser light based on the supplied print data. And a return light detecting means 52 which detects the return light of the laser light obtained by the reflection of the laser light on the ink ribbon 33 and outputs the monitor signal S12 according to the intensity of the return light.
And the laser light irradiation means 51 based on the monitor signal S12.
And a control means 61 for controlling the light output level of the laser light irradiation means 51 by adjusting the amount of operating current supplied to the laser light irradiation means 51.
1 while irradiating the laser light to the ink ribbon 33, the operating current value of the laser light irradiating means 51 when the laser light irradiating means 51 has a suitable light output level for the ink ribbon 33 based on the monitor signal S12. Is set to cause the laser light irradiation means 51 to start printing at this operating current value, and when the signal level of the monitor signal S12 changes during printing, the light output level of the laser light irradiation means 51 becomes a suitable light output level. The operating current value of the laser light irradiating means 51 is predicted, and the laser light irradiating means 51 is driven at the predicted operating current value.

Further, in the present invention, the ink ribbon 33
Is a carbon layer 4 made of a carbon material over the entire surface excluding the code portion 40A and / or the mark portion of the base material 40.
1 is formed.

[0012]

Before the start of printing, the laser light irradiating means 51 irradiates the ink ribbon 33 with laser light while the laser light irradiating means 51 attains a suitable light output level with respect to the ink ribbon 33 based on the monitor signal S12. When the operating current value of the laser light irradiating means 51 at this time is set and the laser light irradiating means 51 starts printing at this operating current value, and the signal level of the monitor signal S12 changes during printing, the laser light irradiating means 51 is changed. By predicting the operating current value of the laser light irradiation means 51 so that the light output level becomes a suitable light output level and driving the laser light irradiation means 51 at the predicted operating current value, the laser light is emitted during printing. The laser light of a suitable light output level is always radiated from the light irradiating means 51 to the ink ribbon 33, and thus the pre-printing having a uniform density characteristic is always performed. The printer device of thermal transfer type which bets image is obtained can be realized.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

(1) Overall Structure In FIG. 1, reference numeral 20 denotes a printer apparatus using a laser head 21 as a whole, and a semiconductor laser 22 is soldered to a harness board 24 via a cylindrical heat sink 23 and then a heat sink. 23 is a laser head housing 2
5 is inserted into a through hole 25C provided so as to penetrate the upper step portion 25A and the lower step portion 25B, and the harness board 24 is inserted into a groove 25D formed in the upper step portion 25A of the laser head housing 25. It is stored in the laser head housing 25. In this case, a disk-shaped cover glass 26 is fixed to the lower surface of the lower step portion 25B of the laser head housing 25 by using an adhesive or the like, and the upper step portion 25 is formed.
On the upper surface of A, a U-shaped substrate fixing spring 27 is arranged on a base portion 25AX formed at one end of the groove 25D, whereby the substrate fixing spring 27 is attached to the semiconductor laser 22 of the harness substrate 24. The front surface of the semiconductor laser 22 is pressed against the cover glass 26 by pressing the surface on the non-open side.

The laser head housing 25 is attached to the lower surface side of a plate-shaped laser head pressure bonding pedestal 28, and the laser head pressure bonding pedestal 28 is provided with a predetermined laser head device moving mechanism (not shown) via a laser head pressure bonding spring 29. ) Is attached to the spring receiving plate 30, and the cover plate 26 is attached to the ink ribbon 33 arranged so that the semiconductor laser 22 comes into close contact with the print paper 32 by moving the spring receiving plate 30 to the platen 31 side. The ink ribbon 33 is pressed through the ink ribbon 33, and in this state, the ink ribbon 33 is irradiated with the diffused light of the laser light.
As shown in FIG. 2, the ink ribbon 33 is formed by sequentially forming a carbon layer 41 and a dye layer 42 using a sublimable dye on one surface of the ribbon base 40, and photothermally converts laser light into the carbon layer 41 to transfer the laser light. By generating heat, the dye in the dye layer 42 is sublimated and transferred to the print paper 32.

(2) APC Control of Printer Device Here, in the semiconductor laser 22, as shown in FIG. 3, a laser diode chip 51 and a photodiode chip 52 are arranged inside the base 50 to emit the return light of the laser light L. The photodiode chip 52 can be used for monitoring, so that the photodiode chip 52 outputs a monitor signal according to the intensity of the returning light. In this case, the printer device 20 is provided with an APC control block 60 as shown in FIG. 4, which prevents the APC control block 60 from changing the optical output of the laser diode chip 51 during printing based on the monitor signal. It is designed to be controlled.

That is, in the APC control circuit block 60, the CPU (central processing unit) 61 has a control signal S
10 is sent to the constant current circuit 64 through the digital-analog conversion circuit 62 and the voltage-current conversion circuit 63. The constant current circuit 64 controls the semiconductor laser 22 based on the control signal S10.
The drive current signal S11 is supplied to the laser diode chip 51, which causes the laser diode chip 51 to emit a laser beam having an intensity corresponding to the control signal S10.
At this time, in the semiconductor laser 22, the photodiode chip 52 monitors the return light of the laser light, converts the monitor current signal S12 corresponding to the intensity of the return light into the current-voltage conversion circuit 65, and then converts this to the monitor voltage signal S13. Is sent to an analog / digital port (not shown) of the CPU 61 via the operational amplifier 66.

Thus, the CPU 61 controls the monitor voltage signal S
Based on 13, the control signal S10 is sent to the constant current circuit 64 according to the magnitude of the voltage applied to the analog / digital port (hereinafter referred to as the monitor voltage) to adjust the optical output of the laser diode chip 51. Thus, the intensity of the laser beam applied to the ink ribbon 33 is kept in a predetermined state so that the printing density of the printer device 20 does not change. In this case, the ink ribbon 3
In FIG. 3, as shown in FIG. 5, the carbon layer 41 is formed over the entire surface of one surface of the ribbon base 40 except for the heading cord portion 40A. As a result, in the ink ribbon, the ink ribbon 33 always reflects the laser light with a predetermined reflectance, except for the heading cord portion 40A,
As a result, the dye layers 42A and 42A are formed at the spot positions of the laser light.
With or without B and 42C, the APC control block 60 is designed to always provide accurate APC control.

In the case of the embodiment, the CPU 61 controls the APC of the optical output level of the laser diode chip 51 in accordance with the print processing procedure RT0 shown in FIG. 6 when printing. That is, in the initial state before printing, the CPU 61 sends a drive signal (not shown) to the winding means (not shown) of the ink ribbon 33 at step SP1 so that the laser light is emitted from the ink ribbon 3.
The ink ribbon 33 is fed so as to irradiate a portion of the layer 3 in which only the dye layer 42A, 42B or 42C is formed. In the following step SP2, the CPU 62 slightly increases the current applied to the laser diode chip 51 from 0 [A] by sending the control signal S10 to the constant current circuit 64, and in the following step SP3, the monitor voltage supplied is changed. Based on this, it is determined whether the optical output of the laser diode chip 51 is optimum for the ink ribbon 33 (hereinafter, the optical output at this time is referred to as the optimum optical output).

If the CPU 61 obtains a negative result in this step SP3, it returns to step SP2, whereas if it obtains an affirmative result, it advances to step SP4 to drive the current value of the laser diode chip 51 at that time (hereinafter, the optimum value). The drive current value) is stored in a storage circuit (not shown). At the subsequent step SP5, the CPU 61 sets the current amount applied to the laser diode chip 51 to 0 [A].
Return to step SP6 and proceed to step SP6 to set the ink ribbon 3
By sending a drive signal to the winding means of No. 2, the ink ribbon 33 is sent so that the laser light irradiates the printing start position on the dye layer 42A, 42B or 42C.

Further, the CPU proceeds to step SP7 and sends the control signal S10 to the constant current circuit 64 to apply the current of the optimum drive current value stored in the memory circuit in step SP4 to the laser diode chip 51. Printing is started, and while monitoring the monitor voltage in the following step SP8, it is determined whether or not the voltage has changed from the monitor voltage obtained in step SP3 (hereinafter referred to as the optimum monitor voltage). The CPU 61
If a negative result is obtained in step SP8, the process proceeds to step SP9, in which the laser diode chip 51 outputs the optimum optical output.
After estimating the drive current value of 1, the process proceeds to step SP10 to rewrite the output data stored in the memory circuit to the obtained estimated value, and then proceeds to step SP11 to determine whether or not printing is completed.

When the CPU 61 obtains a negative result in this step SP11, the CPU 61 returns to step SP8, and thereafter repeats the loop of steps SP8-SP9-SP10-SP11-SP8, whereby the intensity of the laser beam applied to the ink ribbon 33 is increased. The printing is advanced while adjusting the light output of the laser diode chip 51 so that the change in the width does not change.
On the other hand, if the CPU 61 obtains a positive result in this step SP11, it proceeds to step SP12 and sends the control signal S10 to the constant current circuit 64 to return the amount of current applied to the laser diode chip 51 to 0 [A]. In subsequent step SP13, the print processing procedure RT0 is completed.

(3) Operation of the Embodiment In the above-described configuration, the CPU 61 is configured to cause the laser light to irradiate a portion of the ink ribbon 33 where only the carbon layer 41 is formed in the initial state before printing during printing. After being sent to the ink ribbon 33 (step SP1), the control signal S10 is sent to the constant current circuit 64 to gradually increase the drive current of the laser diode chip 51 from 0 [A], and the laser diode based on the monitor voltage. The chip 51 is adjusted so that the optical output is optimum for the ink ribbon 33 (steps SP2 and SP3). As a result, when the monitor voltage becomes the optimum optical output, the operating current of the laser diode chip 51 at this time is adjusted. After storing the value (step SP4), the control signal S1 is sent to the constant current circuit 64.
0 is sent to return the drive current of the laser diode chip 51 to 0 [A] (step SP5).

Subsequently, the CPU 61 causes the laser beam to be applied to the dye layer 42A, 42B or 4 on the winding means of the ink ribbon 33.
After sending the ink ribbon 33 so as to irradiate a predetermined print start position on 2C (step SP6), the control signal S10 is sent to the constant current circuit 64 by the laser diode chip 5.
A drive current having an optimum drive current value is applied to 1 to start printing (step SP7).

Further, the CPU 61 constantly monitors the change in the optical output of the laser diode chip 51 based on the monitor voltage during printing (step SP8), and when the monitor voltage changes, the monitor voltage returns to the optimum monitor voltage. The drive current amount of the laser diode chip 51 is adjusted while estimating the drive current value of the diode chip 51 (steps SP8 to SP11). After this CPU 61
When the predetermined printing is completed, the control signal S10 is sent to return the drive current of the laser diode chip 51 to 0 [A] (step SP12), thereby ending the printing operation (step SP13).

(4) Effects of the Embodiments According to the above construction, the carbon layer 41 is formed on the entire surface of the ink ribbon 33 except the heading cord portion 40A, and then the dye layers 42A, 42B and 42C are formed. ,
Based on the monitor voltage signal S13 supplied from the photodiode chip 52, the CPU 61 detects the drive current value of the laser diode chip 51 when the optimum optical output is obtained for the ink ribbon 33 before printing is started, and detects it. It is stored, and while printing, the current value applied to the laser diode chip 51 is adjusted according to the change of the monitor voltage based on the monitor voltage signal S13, and the optical output of the laser diode chip 51 is always kept constant. As a result, laser light is emitted from the laser diode chip 51 at an optimum light output to the ink ribbon 33 that is being used at all times during printing, and thus changes in the relationship between the laser diode chip 51 and the ink ribbon 33 are caused. Without using a thermal transfer type printer that always produces a printed image with uniform density characteristics. It can realize the printer apparatus.

In this case, the dye layer 42A, 42B and 42C is formed after the carbon layer 41 is formed on the entire surface of the ink ribbon 33 excluding the heading cord portion 40A. It can be determined that it is a head start code, and thus the black mark can be eliminated. Further, in this case, the carbon layer 41 is formed on the entire one surface of the ink ribbon 33 excluding the heading cord 40A.
By forming the carbon ribbon 41 so that the reflectance of the ink ribbon 33 other than the crawling cord 40A with respect to the laser beam becomes constant, various marks can be formed by not forming the carbon layer 41. You can

(5) Other Embodiments In the above-described embodiment, the carbon layer is formed on the entire surface of the ink ribbon 33 excluding the heading cord so that the ink ribbon 33 always reflects the laser light with a constant reflectance. 41
Although the present invention is not limited to this, the point is that the ink ribbon 33 always reflects the laser light with a constant reflectance in a portion other than a predetermined mark such as the heading cord 40A. If possible, an infrared absorbing layer (not shown) made of an infrared absorbing material may be formed instead of the carbon layer 41, or the ribbon base 40 of the ink ribbon 33 may absorb the infrared rays. A material may be included to reflect the laser light with a constant reflectance.

In this case, it is conceivable that the yellow, magenta, and cyan dye layers 42A, 42B, and 42C have different monitor voltage values at the time of optimum light output, but in the printing apparatus 20, the CPU 61 causes the yellow, magenta, and cyan dye layers. By monitoring the monitor voltage with individual constituent curves for the dye layers 42A, 42B and 42C, the laser diode chip 51 can always emit laser light with an optimum light output regardless of the difference in reflectance between the colors. You can

Further, in the above-described embodiment, since the carbon layer 41 is laminated on the entire surface of the ink ribbon 33 other than the heading cord portion 40A, it is possible to determine that the transparent portion is the heading cord portion 40A. Although a case has been described above, the present invention is not limited to this, and the carbon layer 41 is provided on the head-start cord portion 40A and / or other mark portions.
Means that ink or the like having a predetermined reflectance different from the reflectance of the laser light is applied, and when the laser light returns with this reflectance, the CPU 61 sets the laser light irradiation position to the head portion 40A and / or the other. You may make it judge that it is a mark part.

[0031]

As described above, according to the present invention, the ink ribbon is formed so that the reflectance of the laser light becomes substantially uniform, and the laser is applied while the dye is not emitted to the ink ribbon before the start of printing. Light is emitted to detect a suitable laser light output level for the ink ribbon, printing is started at this output level, and the return light from the ink ribbon is monitored while monitoring the intensity of the return light from the ink ribbon. By adjusting the output level of the laser light so that the intensity of the ink does not change, the ink ribbon is always irradiated with the laser light of a suitable output level during printing, thus ensuring that the density characteristics are always uniform. A thermal transfer type printer device capable of obtaining a print image can be realized.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of a printer device according to the present invention.

FIG. 2 is a schematic side view showing a configuration of an ink ribbon according to an example.

FIG. 3 is a schematic perspective view showing a positional relationship between a laser diode chip and a photodiode chip.

FIG. 4 is a block diagram showing an APC control circuit block of the printer device according to the embodiment.

FIG. 5 is a schematic plan view showing a format of an ink ribbon according to an example.

FIG. 6 is a flow chart showing a print processing procedure.

FIG. 7 is a block diagram showing a temperature correction circuit block of a printer device using a thermal head.

FIG. 8 is a schematic plan view showing a conventional ink ribbon format.

[Explanation of symbols]

10, 33 ... Ink ribbon, 11, 40 ... Ribbon base, 12A-12C, 42, 42A-42C ... Dye layer, 13, 40A ... Heading code, 20 ... Printer device, 22 ... Laser head, 22 ... Semiconductor laser,
32 ... Print paper, 51 ... Laser diode chip, 52 ... Photodiode chip, 60 ... APC control block, 61 ... CPU, 64 ... Constant current circuit, S
10 ... control signal, S11 ... drive current signal, S12 ...
... Monitor current signal, S13 ... Monitor voltage signal.

Continuation of front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location B41J 2/325 29/46 D 9113-2C H04N 1/23 103 Z 9186-5C 9305-2C B41J 3/20 109 A 9305-2C 117 A 9305-2C 117 C

Claims (2)

[Claims] 1. A thermal transfer type printer device using a laser head, wherein an ink ribbon having a substantially uniform reflectance with respect to laser light is supplied over the entire surface except for a predetermined code part and / or mark part. Laser light irradiating means for irradiating the ink ribbon with the laser light based on print data, and detecting return light of the laser light obtained by reflecting the laser light on the ink ribbon, and returning the laser light. The light output level of the laser light irradiating means is adjusted by adjusting the amount of operating current supplied to the laser light irradiating means on the basis of the return light detecting means for outputting a monitor signal according to the intensity of light and the monitor signal. And a control means for controlling, wherein the control means irradiates the laser light irradiation means with the laser light on the ink ribbon before printing is started. While operating, the operating current value of the laser light irradiating means when the laser light irradiating means has a suitable light output level for the ink ribbon is set based on the monitor signal, and the laser light irradiating means performs this operation. Start printing with current value,
When the signal level of the monitor signal is changed during printing, the operation current value of the laser light irradiation means is predicted so that the light output level of the laser light irradiation means becomes the preferable light output level, and the predicted operation is performed. A printer device, characterized in that the laser light irradiation means is driven by a current value. 2. The ink ribbon according to claim 1, wherein a carbon layer made of a carbon material is formed over the entire surface of the base material excluding the code portion and / or the mark portion. Printer device.