JP4005500B2 - Laser marking method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form individual dots of uniform quality irrespective of output changes in a laser beam oscillating tube when forming a marking pattern by dot array on a photosensitive material. <P>SOLUTION: In a marking device, when the treatment start instruction of an X-ray film is inputted, oscillation of a laser beam oscillating tube is started. When the output of the laser beam oscillating tube becomes stable and the treatment is ready to start, carriage of the X-ray film is started, and the X-ray film is irradiated with laser beams as the X-ray film is carried (Steps 100-106). When carriage of the X-ray film is stopped, oscillation of the laser beam oscillating tube is continued until a lapse of predetermined time (time T<SB>I</SB>). When the film is stopped for a short time, marking of the X-ray film is rapidly started (Steps 108-116). <P>COPYRIGHT: (C)2004,JPO&amp;NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a laser marking method for irradiating a photosensitive material with laser light to form a marking pattern such as characters and symbols on the photosensitive material.
[0002]
[Prior art]
In a photosensitive material such as a medical X-ray film, characters and the like are recorded on the edge portion so that the manufacturer name, product type, lot, etc. can be identified. When recording characters or symbols on a photosensitive material such as an X-ray film, the photosensitive material is irradiated with a laser beam (laser beam) to cause heat fogging or deformation on the surface of the photosensitive material. A marking technique is known in which dots are formed and a marking pattern such as characters and symbols is formed by this dot arrangement.
[0003]
For example, in the X-ray film 90 as shown in FIGS. 14A and 14B, when the laser beam is irradiated, the emulsion layer melts and evaporates due to the energy of the laser beam. In this process, a large number of minute bubbles are generated in the emulsion layer 92 that expands, and dots are formed.
[0004]
As shown in FIG. 14A, in the highly visible dot 94, the surface becomes convex (convex) due to a large number of bubbles generated in the emulsion layer 92, and the boundary film between a large number of fine bubbles is used. The diffuse reflection of light is promoted, and the amount of reflected light changes greatly between the inside and outside of the dot 94.
[0005]
When characters and symbols are formed using such a dot arrangement, it is necessary to appropriately set the dot diameter and the dot interval. However, high visibility for individual dots, that is, high finishing quality is required for the dots 94. The
[0006]
At this time, for example, when energy is applied to the emulsion layer 92 more than necessary by a laser beam, the emulsion layer 16 is melted and opened as shown in FIG. 14B, and the base layer 96 as a support is exposed. Dots 98 are formed.
[0007]
In such a dot 98, in the X-ray film 90 or the like having a high light transmittance of the emulsion layer 92, it becomes difficult to distinguish the emulsion layer 92 from the exposed base layer 96, so that it cannot be visually recognized. That is, the visibility of the dots 98 is extremely low, and the visibility of characters and symbols formed by the dot arrangement including the dots 98 is also extremely low.
[0008]
Therefore, when forming highly visible dots (dots 94) on the X-ray film using a laser beam, the X-ray film is controlled by the energy of the laser beam by appropriately controlling the irradiation time of the laser beam to the X-ray film. It is intended to cause proper deformation in the.
[0009]
Thus, the visibility of the marking pattern formed by dot arrangement can be improved by improving the visibility of individual dots.
[0010]
By the way, in the laser oscillation tube which oscillates a laser beam, the output peak immediately after the start of driving is high, the output gradually decreases by continuing the driving, and stabilizes to a steady output state after a predetermined time elapses.
[0011]
When using such a laser oscillator tube to form a character with a dot array or a marking pattern in which a plurality of characters are recorded continuously, the dot formed immediately after the start of marking or the character formed by this dot array is visible. It becomes extremely low. That is, when the photosensitive material is irradiated with a laser beam in a state where the output peak is high, the emulsion layer melts and evaporates and the base layer is exposed.
[0012]
When marking with a laser beam, as a method of preventing the influence of the output peak that occurs immediately after the laser oscillation tube starts driving, when marking is performed by driving the laser oscillation pulse, the shutter is closed. It has been proposed to start marking of the laser oscillation tube and thereafter perform marking by actual pulse driving with the shutter opened (see, for example, Patent Document 1).
[0013]
Thus, marking using a laser beam can be performed without being affected by an output peak generated immediately after the start of driving of the laser oscillation tube.
[0014]
[Patent Document 1]
JP 2000-52069 A
[0015]
[Problems to be solved by the invention]
However, when the laser oscillation tube is continuously driven by a pulse, an output peak occurs immediately after the start of driving, and an output peak appears at the beginning even when driving by each driving pulse, and gradually toward a steady state output. Output decreases.
[0016]
That is, when a laser oscillation tube is continuously driven when forming one character or character string, the output of the laser beam is extremely high immediately after the start of driving, as shown in FIG. To stabilize in steady state. On the other hand, when the laser oscillation tube is pulse-driven, as shown in FIG. 15B, the output peak of the laser oscillation tube driven by each pulse gradually decreases. However, an output change occurs, the output is highest immediately after the start of driving, and the output rapidly decreases.
[0017]
Such a change in the output of the laser beam emitted from the laser oscillation tube may cause the energy of the laser beam to concentrate on a part when forming dots on the photosensitive material.
[0018]
This causes, for example, the emulsion layer to melt and evaporate at the center of the dot, for example, thereby exposing the base layer and causing dot deformation and dot diameter reduction. Even when such dots are formed, there is a problem that the visibility of characters and symbols formed by the dots and the dot arrangement is lowered.
[0019]
The present invention has been made in view of the above-mentioned facts, and it is possible to form a high-quality and highly visible marking pattern and dot marking pattern on a photosensitive material regardless of changes in the output of laser oscillation means such as a laser oscillation tube. The purpose is to propose a laser marking method.
[0020]
[Means for Solving the Problems]
The invention according to claim 1 for achieving the above object is characterized in that characters are formed on the photosensitive material by an array of dots formed by irradiating a laser beam oscillated by a laser oscillation means while conveying the photosensitive material. , symbol Or multiple letter , symbol Lined up letter Column A laser marking method for forming a marking pattern, which starts oscillation of laser light by the laser oscillation means prior to irradiation of the laser light to the photosensitive material, and after the oscillation output of the laser oscillation means has stabilized, The marking material is formed on the photosensitive material by irradiating the photosensitive material while deflecting the laser beam in accordance with the marking pattern by a deflecting unit, and the conveyance of the photosensitive material after the formation of the marking pattern is stopped. After that, the time from when the laser oscillation means starts oscillation until the oscillation output is stabilized Longer When the conveyance of a new photosensitive material is not started before the set time elapses, the laser oscillation is stopped by the laser oscillation means.
[0021]
According to the present invention, prior to forming the dots by irradiating the photosensitive material with laser light, the laser oscillation means is driven to start oscillation of the laser light, and the oscillation output of the laser oscillation means is in a stable state. Irradiate the photosensitive material with laser light.
[0022]
At this time, the laser beam is deflected by the deflecting means to form dots corresponding to the marking pattern on the photosensitive material.
[0023]
Thereby, since the individual dots forming the marking pattern can be recorded on the photosensitive material with uniform quality, a highly visible marking pattern can be formed on the photosensitive material. Before starting the oscillation of the laser beam by the laser oscillation means until the oscillation output is stabilized, without irradiating the photosensitive material with the laser beam, a predetermined constant part such as inside or outside of the apparatus, For example, what is necessary is just to irradiate a damper etc.
[0024]
According to a second aspect of the present invention, a character array is formed on the photosensitive material by a dot array formed by irradiating a laser beam oscillated by laser oscillation means while conveying the photosensitive material. , symbol Or multiple letter , symbol Lined up letter Column A laser marking method for forming a marking pattern, starting oscillation of laser light by the laser oscillation means, The oscillation started Laser oscillation means of Oscillation output is stable The position on the photosensitive material where the marking pattern is formed is set to reach the irradiation position of the laser beam. The conveyance of the photosensitive material is started at the timing. The , To the photosensitive material that has reached the irradiation position The laser beam is deflected according to the marking pattern by a deflecting unit. Rasho The marking pattern is formed on the photosensitive material, and after the formation of the marking pattern is stopped, the conveyance of the photosensitive material is stopped, and then the time from the start of oscillation of the laser oscillation means to the stabilization of the oscillation output Longer When the conveyance of a new photosensitive material is not started before the set time elapses, the laser oscillation is stopped by the laser oscillation means.
[0025]
According to this invention, In a state where the output of the laser oscillation means is stable, the position where the marking pattern is formed on the photosensitive material reaches the irradiation position of the laser beam. After starting the oscillation of the laser beam by the laser oscillation means, the photosensitive material is started to be conveyed. Thereby, in a state where the oscillation output of the laser oscillation means is stable, the photosensitive material can be irradiated with laser light to form dots, so that a highly visible marking pattern can be formed on the photosensitive material. .
In the inventions according to claims 1 and 2, when the conveyance of the photosensitive material is stopped and the stop time is short, the oscillation of the laser oscillation means is continued.
Accordingly, if the interruption is performed for a short time, the photosensitive material can be marked by starting the conveyance of the photosensitive material, so that the production efficiency can be prevented from being lowered.
[0026]
In such an invention, the timing for starting the conveyance of the photosensitive material The The laser oscillation means After starting oscillation The time until the output of the laser beam is stabilized can be set.
[0027]
In the present invention, the timing of starting the conveyance of the photosensitive material The The output of the laser beam oscillated by the laser oscillation means is stabilized before the position of forming the marking pattern of the photosensitive material reaches the irradiation position of the laser beam. After the laser oscillation means starts oscillating In any of these, when the laser beam is applied to the photosensitive material, the oscillation output of the laser oscillation means can be stabilized.
[0028]
In the present invention, After the laser oscillation means starts oscillating Start conveying the photosensitive material Time , Preset based on the output change of the laser oscillation means Anything can be used. Also, In the present invention, The timing of starting the conveyance of the photosensitive material may be determined based on the detection result by detecting the laser light oscillated by the laser oscillation means.
[0032]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a schematic configuration of a marking device 10 applied to the present embodiment.
[0033]
The marking device 10 irradiates the surface of the X-ray film 12 by irradiating the surface with a laser beam LB to form a dot or a dot array. A marking pattern such as a character string or a symbol or a plurality of characters or symbols is formed.
[0034]
An X-ray film 12 applied as a photosensitive material in the present embodiment is a photothermographic material for medical use, and as shown in FIG. 2A, a base that is a support using PET (polyethylene terephthalate) or the like. It has a multilayer shape including a layer 14 and an emulsion layer 16 formed by coating an emulsion on at least one surface of the base layer 14.
[0035]
As shown in FIG. 1, the X-ray film 12 to be processed by the marking device 10 is loaded as a roll 20 wound up in layers on a winding core 18 so that the emulsion layer 16 faces outward, for example.
[0036]
In the marking device 10, small rolls 22 and 24 are arranged in the vicinity of the loading position of the roll 20, and the X-ray film 12 drawn from the roll 20 is first wound around the small roll 22.
[0037]
A suction drum 26 is provided between the small rolls 22 and 24, and a substantially U-shaped conveyance path is formed by the small rolls 22 and 24 and the suction drum 26. It is wound around the outer peripheral surface of the suction drum 26 so that the emulsion layer 16 side faces outward between the rolls 22 and 24.
[0038]
The suction drum 26 has a large number of small holes (not shown) formed on the outer peripheral surface thereof, and suction and hold the X-ray film 12 wound around the outer peripheral surface by supplying negative pressure to these small holes. . Further, in the marking device 10, as an example, the suction drum 24 is moved upward in FIG. 1 by the urging force of the urging means (not shown). A constant tension is applied to 12.
[0039]
In the marking device 10, the suction drum 26 is rotationally driven at a predetermined rotational speed by a driving force of a driving means (not shown).
[0040]
Thereby, the X-ray film 12 is conveyed while being pulled out from the roll 20 at a line speed corresponding to the rotational speed of the suction drum 26, and is sent out from the small roll 24.
[0041]
A pass roll 28 is provided in the vicinity of the small roll 24, and the X-ray film 12 is wound around the pass roll 28 to change the transport direction upward.
[0042]
A print roll 30 is provided above the pass roll 28, and the X-ray film 12 is directed in the horizontal direction by being wound around the print roll 30. At this time, by applying a predetermined tension to the X-ray film 12, the X-ray film 12 is tightly wound around the peripheral surface of the print roll 30 so that the emulsion layer 16 side faces outward.
[0043]
In the marking device 10, a pass roll 32 is provided on the horizontal direction side of the print roll 30, and a reverse roll 34 is provided below the pass roll 32.
[0044]
The X-ray film 12 wound around the print roll 30 and sent out is redirected downward by being wound around the pass roll 32, and further wound around the reversing roll 34 and then wound around the core 36. It is done. At this time, like the roll 20, for example, it is wound around the core 36 so that the emulsion layer 16 side faces outward.
[0045]
On the other hand, the marking device 10 is provided with a winding control device 38 for controlling the operation. The winding control device 38 controls a driving source (not shown) to rotate the suction drum 26, the winding core 36, and the like. To drive.
[0046]
As a result, the X-ray film 12 drawn from the roll 20 is wound around the print roll 30 and then reaches the core 36 to be wound around the core 36 in layers.
[0047]
The suction drum 26 is provided with a rotary encoder (not shown). The rotary shaft of the rotary encoder rotates together with the suction drum 26 and outputs a pulse signal corresponding to the rotation angle of the suction drum 26. The winding control device 38 can detect the transport speed and transport length of the X-ray film 12 by measuring this pulse signal.
[0048]
On the other hand, the marking device 10 is provided with a marking head 40 and a laser control device 42 that controls the operation of the marking head 40.
[0049]
A pulse signal corresponding to the rotation of the suction drum 26 is input from the rotary encoder to the laser control device 42. The laser control device 42 transports the X-ray film 12 based on the pulse signal. The operation of the marking head 40 is controlled while monitoring the speed and the conveyance length.
[0050]
As shown in FIGS. 1 and 3, a laser oscillation tube 44 provided as laser oscillation means and a beam deflector 46 provided as beam deflection means are arranged in the marking head 40. Further, the marking head 40 includes a lens barrel 48 including a condenser lens (not shown).
[0051]
The laser oscillation tube 44 applied to the present embodiment is made of CO. ₂ It is a laser and emits a laser beam LB having a constant oscillation wavelength based on a drive signal from the laser controller 42.
[0052]
The beam deflector 46 includes, for example, an AOD (acousto-optic device), and based on the deflection signal input from the laser control device 42, the laser beam LB emitted from the laser oscillation tube 44 is converted into the X ray film 12. Injecting toward the X-ray film 12 wound around the print roll 30 while deflecting along the width direction.
[0053]
The laser beam LB is condensed by passing through the lens barrel 48 and irradiated so as to have a predetermined spot diameter on the X-ray film 12.
[0054]
In the X-ray film 12, many fine bubbles are generated in the process in which the emulsion layer 16 is melted and evaporated by being irradiated with the laser beam LB. In the X-ray film 12, a large number of bubbles are generated, so that irregular reflection of light occurs in the boundary film between the bubbles, and a recognizable dot is formed regardless of whether it is undeveloped or developed or whether the density is dark or light. .
[0055]
In the marking device 10, characters, symbols, and the like are formed by the dot arrangement, and a character string in which these characters, symbols, and the like are arranged at a predetermined interval is formed on the X-ray film 12 as a marking pattern MP.
[0056]
The laser control device 42 outputs a drive signal to the laser oscillation tube 44 so that a pattern signal corresponding to the marking pattern MP to be formed on the X-ray film 12 in a state in which the laser oscillation tube 44 is being driven, For example, when input from the winding control device 38, a deflection signal is output to the beam deflector 46 in accordance with the pattern signal.
[0057]
Thereby, the X-ray film 12 wound around the print roll 30 is scanned with the laser beam LB in accordance with the marking pattern MP to be formed.
[0058]
At this time, the laser controller 42 monitors the transport length of the X-ray film 12 based on the pulse signal output from the rotary encoder provided in the suction drum 26, and the beam is sent every time the transport length reaches a predetermined length. A deflection signal is output to the deflector 46.
[0059]
Thereby, in the marking apparatus 10, a marking pattern is formed on the X-ray film 12 at a predetermined interval. That is, in the marking device 10, as shown in FIG. 2B, the X-ray film 12 transport direction (the direction of arrow A in FIG. 2B) is the sub-scanning direction, and the scanning direction of the laser beam LB is the main scanning. As the direction, the dot-shaped marking pattern MP is formed by irradiating the laser beam LB. FIG. 2B shows a marking pattern MP in which alphabets are formed with a 5 × 5 dot array as an example.
[0060]
When such an X-ray film 12 is cut (slit) at an intermediate portion in the width direction, marking patterns MP are provided on both sides of the slit line 50 (see FIGS. 2B and 3) that is the slit position. Form. At this time, it is also possible to form a marking pattern MP in which the direction of the top and bottom is reversed across the slit line 50.
[0061]
When forming a highly visible marking pattern MP on the X-ray film 12, it is necessary that the individual dots have high visibility, and the irradiation time of the laser beam LB for forming such dots is as follows: When the oscillation wavelength of the laser oscillation tube 44 (the wavelength of the laser beam LB) is 9 μ band (for example, a wavelength of 9.3 μm, 9.6 μm, etc.), the oscillation wavelength of the laser oscillation tube 44 is, for example, in the range of 1 μsec to 15 μsec. In the 10 μm band (for example, 10.6 μm), the irradiation time of the laser beam LB can be set to, for example, 5 μsec to 18 μsec.
[0062]
Moreover, as a dot diameter, it is preferable that it is 0.18 mm or more, and it is more preferable that it is 0.2 mm or more. In the marking head 40, in order to form such a dot diameter, the spot diameter of the laser beam LB irradiated on the X-ray film 12 is set to about 0.2 mm or more.
[0063]
In addition, the visibility of the marking pattern MP affects not only the dot diameter but also the dot pitch, which is the center interval between dots. In order to form the marking pattern MP with high visibility, P / D which is the ratio of the dot pitch P is set to 1.5 or less.
[0064]
On the other hand, in the marking device 10, prior to the irradiation of the X-ray film 12 with the laser beam LB, the laser oscillation tube 44 is driven to start transporting the X-ray film 12 at a predetermined timing. Each time the length reaches a predetermined length, the X-ray film 12 is irradiated with the laser beam LB by outputting a deflection signal corresponding to the pattern signal of the marking pattern MP to the beam deflector 46.
[0065]
FIG. 4 shows an example of an output change of the laser beam LB oscillated by the laser oscillation tube 44. The laser oscillation tube 44 provided in the marking head 40 starts oscillation of the laser beam LB when a drive signal is input.
[0066]
At this time, the laser oscillation tube 44 is in a state where the output peak of the laser beam LB immediately after the start of driving, the output decreases with time, and the steady output Pa is output. In the present embodiment, the steady output state of the laser oscillation tube 44 is a state in which the output change of the laser beam LB is within ± 3% of the steady value Pa.
[0067]
In the X-ray film 12, if the irradiation time of the laser beam LB is set so that an appropriate dot is formed when the laser beam LB whose output is in a steady state is irradiated, the output of the laser beam LB is large. More energy than necessary is supplied to the emulsion layer 16 and the visibility of dots is reduced.
[0068]
That is, in the X-ray film 12, when the output of the laser beam LB is too large, the emulsion layer 16 is melted and evaporated, and the base layer 14 is exposed, so that the dot visibility is lowered. .
[0069]
Such a drop in the visibility of dots causes a drop in visibility and a reduction in finished quality due to missing dots in characters and symbols formed by the dot arrangement.
[0070]
Further, the laser beam LB irradiated to the X-ray film 12 has a peak at the center of the beam (indicated by a one-dot chain line in FIG. 5A) in a steady output state as shown in FIG. 5A. The Gaussian beam has a Gaussian distribution. In this Gaussian beam, a line (indicated by a broken line in FIG. 5A) in which the intensity is reduced by about 86.5% with respect to the peak value is a beam diameter, and the X-ray film 12 corresponds to the beam diameter. Dots are formed.
[0071]
On the other hand, in the state where the output is unstable immediately after the start of driving of the laser oscillation tube 44, the intensity distribution of the laser beam LB does not become a Gaussian beam. For example, as shown in FIG. May have a distribution with an intensity peak. In FIGS. 5A and 5B, the horizontal axis is the beam diameter direction.
[0072]
If the X-ray film 12 is irradiated with the laser beam LB having such an intensity distribution, an appropriate number of dots cannot be formed at an appropriate position.
[0073]
Thus, for example, when a character string as shown in FIG. 5C is to be formed on the X-ray film 12 as the marking pattern MP, as shown in FIG. A plurality of dots may be formed.
[0074]
In order to prevent such a drop in dot quality, the marking device 10 drives the laser oscillation tube 44 of the marking head 40, that is, oscillates the laser beam LB, prior to the processing of the X-ray film 12. The processing of the X-ray film 12, that is, the conveyance of the X-ray film 12 is started after a preset time has elapsed so that the output of the laser oscillation tube 44 is stabilized. When the conveyance of the X-ray film 12 is stopped and the processing for the X-ray film 12 is interrupted or terminated, the oscillation operation of the laser oscillation tube 44 is not stopped until a predetermined time has elapsed.
[0075]
At this time, in the marking device 10, the time from the start of the oscillation of the laser beam LB by the laser oscillation tube 44 to the start of the conveyance of the X-ray film 12 is the time until the output of the laser oscillation tube 44 is stabilized. Set based on.
[0076]
In the marking device 10, the time from the start of driving of the laser oscillation tube 44 to the start of conveyance of the X-ray film 12 is taken as an example, from the start of oscillation of the laser beam LB by the laser oscillation tube 44 to the laser. Time T with a margin of about 10% in the time until the output of the oscillation tube 44 reaches a steady state and stabilizes ₀ Is set.
[0077]
Thereby, in marking device 10, when forming marking pattern MP, conveying X-ray film 12, the output of laser beam LB irradiated to X-ray film 12 is made into the stable state.
[0078]
When the conveyance of the X-ray film 12 is stopped, this time T ₀ In addition, the operation of the laser oscillating tube 44 is not stopped during the time when the margin is further increased, so that the processing of the X-ray film 12 can be started immediately after the roll 20 or the like is replaced. I am doing so.
[0079]
As shown in FIG. 6, the marking head 40 is provided with a damper 52 that absorbs the energy of the laser beam LB in the lens barrel 48, and the laser control device 42 irradiates the X-ray film 12 with the laser beam LB. While not being performed, a deflection signal is output to the beam deflector 46 so that the damper 52 is irradiated with the laser beam LB.
[0080]
That is, when the laser control device 42 starts driving the laser oscillation tube 44, it outputs a deflection signal to the beam deflector 46 so that the laser beam LB is irradiated onto the damper 52, and applies the marking pattern MP to the X-ray film 12. When forming, a deflection signal is output so that the laser beam LB applied to the damper 52 is applied to a predetermined position of the X ray fill 12.
[0081]
At this time, the laser control device 42 controls the irradiation time of the laser beam LB so that appropriate dots can be formed on the X-ray film 12 by appropriately controlling the deflection signal.
[0082]
The laser oscillation tube 44 generates heat by emitting a laser beam LB. The damper 52 irradiated with the laser beam LB generates heat by absorbing the energy of the laser beam LB.
[0083]
For this reason, the marking head 40 and the lens barrel 48 provided in the marking head 40 have a general configuration in which cooling means using, for example, a water cooling method is formed. It is possible to prevent the output change of the laser beam LB due to the temperature rise of the marking head 40 and the deviation of the deflection position of the laser beam LB from occurring.
[0084]
On the other hand, the beam deflector 46 using AOD deflects the laser beam LB in accordance with the ultrasonic frequency input as a deflection signal. At this time, in the beam deflector 46, for example, the center frequency f ₀ On the other hand, the deflection angle changes according to the frequency f of the input deflection signal. In accordance with the change in the deflection angle, the irradiation position of the laser beam LB onto the X-ray film 12 changes along the width direction of the X-ray film 12 which is the main operation direction.
[0085]
FIG. 7 shows an outline of the deflection efficiency of the AOD used in the beam deflector 46 with respect to the frequency f input as a deflection signal. In the beam deflector 46 (AOD), the frequency f is the center frequency f. ₀ There is little change in deflection efficiency in the vicinity of, and it is substantially flat. On the other hand, the frequency f is the center frequency f. ₀ If the change is large, the deflection efficiency is drastically reduced.
[0086]
Such a decrease in deflection efficiency causes attenuation in the laser beam LB, making it difficult to form dots with high visibility, and causes marking defects such as missing dots.
[0087]
In order to prevent this, the laser controller 42 uses the center frequency f. ₀ Near the average deflection efficiency Pea in the region where the change in deflection efficiency is small and substantially flat, for example, at a frequency where the deflection efficiency Pe is within a range of ± 10% (a range indicated by a two-dot chain line in FIG. 7). A range from a certain frequency fa to a frequency fb is used. In addition, the marking head 40 is provided so that the laser beam LB deflected in the range of the frequencies fa to fb is irradiated on the region where the marking pattern MP is to be formed on the X-ray film 12.
[0088]
Thereby, in the marking device 10, uniform dots can be formed on the X-ray film 12. The deflection of the laser beam LB is preferably used in a range where the deflection efficiency Pe is within ± 10% of the average deflection efficiency Pea. However, the practical range of the deflection efficiency Pe when performing laser marking is an average. Since it can be in the range of + 10% to −30% with respect to the deflection efficiency Pea, it is preferable that the laser beam LB is set to be deflected at least within the range of the deflection efficiency Pe.
[0089]
In the marking apparatus 10 configured as described above, the marking pattern MP is formed using the deflection signal based on the pattern signal. Therefore, the marking formed on the X-ray film 12 by changing the pattern signal. The pattern MP can be easily changed.
[0090]
That is, in the marking device 10, since the marking pattern MP is formed by the dot arrangement formed by the laser beam LB irradiated to the X-ray film 12, a pattern corresponding to the marking pattern MP to be recorded on the X-ray film 12 is used. By inputting a signal to the laser control device 42, any character or symbol can be formed as the marking pattern MP, and part or all of the marking pattern MP formed on the X-ray film 12 can be easily changed. Can be done.
[0091]
Below, marking to the X-ray film 12 by the marking apparatus 10 is demonstrated as an effect | action of this implementation.
[0092]
FIG. 8 shows an outline of processing when the marking device 10 performs marking processing (processing processing) on the X-ray film 12.
[0093]
In the marking device 10, for example, a processing start request is input by instructing marking processing on the X-ray film 12 from a higher-level production management device or by operating the operation switch while the roll 20 is loaded. Thus, an affirmative determination is made in the first step 100 of the flowchart shown in FIG. 8, and marking processing for the X-ray film 12 is started.
[0094]
In the winding control device 38 provided in the marking device 10, when an affirmative determination is made in step 100, the process proceeds to step 102, and first the oscillation start requesting the laser control device 42 to operate the laser oscillation tube 44 is started. Output a signal.
[0095]
In FIG. 9, the outline of the marking process using the marking head 40 in the laser control apparatus 42 is shown.
[0096]
In this flowchart, it is confirmed in the first step 120 whether or not an oscillation start signal has been input from the winding control device 38. In step 102 of FIG. 8 described above, the winding control device 38 performs the laser control device 42. An affirmative determination is made at step 120 of this flowchart by outputting an oscillation start signal.
[0097]
Accordingly, the process proceeds to step 122, where a drive signal is output to the laser oscillator 44, and oscillation of the laser beam LB in the laser oscillator 44 is started. At this time, the laser controller 42 outputs a deflection center to the beam deflector 46 so that the laser beam LB is irradiated to the damper 52 provided in the lens barrel 48.
[0098]
In the next step 124, the elapsed time from the start of the oscillation of the laser beam LB by the laser oscillator 44 is a preset time T. ₀ Whether or not the time has passed and the elapsed time is time T ₀ When the determination is affirmative in step 124, the process proceeds to step 126, and a process start signal is output to the winding control device 38.
[0099]
Time T at this time ₀ Is the time until the output of the laser beam LB oscillated by the laser oscillation tube 44 is stabilized in a steady state. From here, the winding control device at the timing when the output of the laser beam LB is stabilized in the laser control device 42. A processing start signal is output to 38.
[0100]
As shown in FIG. 8, when the winding control device 38 outputs the oscillation start signal in step 104, in the next step 104, it is confirmed whether or not a processing start enable signal has been input, and the laser control device 42. However, when a signal indicating that the process can be started is output (step 124 in FIG. 9), an affirmative determination is made in step 104, the process proceeds to the next step 106, and the rotation of the suction drum 26 and the like is started, whereby the roll While the X-ray film 12 is pulled out from 20, the conveyance of the X-ray film 12 is started.
[0101]
That is, as shown in FIG. 10, in the marking device 10, the laser beam LB is oscillated by the laser oscillation tube 44 and the time T ₀ When only the X-ray film 12 elapses, marking on the X-ray film 12 becomes possible, and at this timing, conveyance for processing for the X-ray film 12 is started.
[0102]
On the other hand, as shown in FIG. 9, when a process start enable signal is output to the laser control device 42, the process proceeds to step 128 to perform the marking process.
[0103]
This marking process is performed while monitoring the conveyance speed and conveyance length of the X-ray film 12 from the output of a rotary encoder (not shown) provided on the suction drum 26, and the winding control device 38 conveys the X-ray film 12. When started, the X ray film 12 is irradiated with the laser beam LB each time the transport length of the X ray film 12 reaches a predetermined length, and marking patterns MP are formed on the X ray film 12 at predetermined intervals.
[0104]
As shown in FIG. 11A, the laser oscillating tube 44 provided in the marking head 40 is in a state where the oscillation of the laser beam LB is continued, whereby the output of the laser beam LB is stable. It has become.
[0105]
In this state, the laser control device 42 generates a marking signal (marking signal ON) when the transport length of the X-ray film 12 reaches a predetermined length. Accordingly, the laser control device 42 outputs a deflection signal to the beam deflector 46 based on the pattern signal of the marking pattern MP.
[0106]
The laser beam LB applied to the damper 52 is deflected toward the X-ray film 12 by being deflected based on the pattern signal of the marking pattern MP, and is applied to the X-ray film 12.
[0107]
Accordingly, as shown in FIG. 11B, the laser beam LB is transmitted in the longitudinal direction of the X-ray film 12 (the direction of arrow L in FIG. 11B), which is the transport direction (sub-scanning direction), and in the main scanning direction. The irradiation position is deflected along the width direction of the X-ray film 12 (direction of arrow W in FIG. 11B).
[0108]
At this time, the laser controller 42 deflects the laser beam LB using a region where the deflection efficiency of the beam deflector 46 (AOD) is substantially constant. As shown in FIG. 11C, characters and the like are formed with a highly visible dot arrangement. 11B and 11C show an example in which the alphabet “A” is formed in a 5 × 5 dot array.
[0109]
On the other hand, as shown in FIG. 8, the winding control device 38 confirms whether or not a predetermined stop signal is input in step 108.
[0110]
Here, when an affirmative determination is made in step 108 by inputting a stop signal for exchanging the roll 20 or stopping the operation of the apparatus, the process proceeds to step 110 and the conveyance of the X-ray film 12 is stopped. In the next step 112, the measurement of the stop time T is started by resetting / starting a timer (not shown).
[0111]
In step 114, the stop time T is set to a preset time T. _I In step 116, it is confirmed whether or not the next processing start request has been input.
[0112]
Here, stop time T is time T _I Is reached, an affirmative determination is made in step 114, the process proceeds to step 118, and an oscillation stop signal for the laser oscillation tube 44 is output to the laser controller 42.
[0113]
As shown in FIG. 9, the laser control device 42 checks whether or not an oscillation stop signal has been input in step 130 while performing the marking process (step 128) on the X-ray film 12, and takes up the winding control device 38. However, by outputting an oscillation stop signal at step 118 in FIG. 8, an affirmative determination is made at step 130 and the routine proceeds to step 132 where the oscillation of the laser oscillation tube 44 is stopped.
[0114]
On the other hand, in the flowchart of FIG. _I When the processing start signal is input before reaching, an affirmative determination is made at step 116 and the routine proceeds to step 106.
[0115]
Thereby, conveyance of X ray film 12 is started and marking processing accompanying conveyance of this X ray film 12 is performed.
[0116]
That is, as shown in FIG. 10, in the marking device 10, the stop time T is the time T. _I When the conveyance of the X-ray film 12 is not satisfied, the laser beam LB is continuously oscillated by the laser oscillating tube 44 and the X-ray film 12 can be marked.
[0117]
On the other hand, the stop time T is equal to the time T _I When the value exceeds, the operation of the laser oscillation tube 44 is stopped.
[0118]
In the marking device 10, when the stop time T is long, the oscillation of the laser oscillation tube 44 is stopped. When the stop time T is short, the laser oscillation tube 44 is continuously oscillated to instruct the X ray film 12 to start processing. Is input, the processing of the X-ray film 12 can be started quickly.
[0119]
That is, in the marking device 10, when the processing of the X-ray film 12 is started from the state where the laser oscillation tube 44 has stopped oscillating, the start of the processing is delayed until the output of the laser oscillation tube 44 is stabilized. Yes.
[0120]
For this reason, if the oscillation of the laser oscillation tube 44 is stopped every time the processing stop signal of the X-ray film 12 is input, even if the processing start instruction of the X-ray film 12 is input, the X-ray film is immediately 12 processes cannot be started.
[0121]
For this, the time T _I The stop time T is set to this time T _I By stopping the oscillation of the laser oscillating tube 44 only when it is longer than this, the processing of the X-ray film 12 can be resumed quickly when the stop time T is short.
[0122]
Such a time T _I Is the time T ₀ For example, the time T _I At least time T ₀ It may be set longer and more preferably set based on the operating state of the marking device 10.
[0123]
That is, when the marking device 10 is operated, when there are frequent stops of about 5 minutes due to the replacement of the roll 20, etc., the time T _I At least 5 minutes and time T ₀ What is necessary is just to set so that it may become longer.
[0124]
As a result, it is possible to prevent a reduction in work efficiency due to the necessity of starting up the laser oscillation tube 44 every time a relatively short stop frequently occurs in the marking device 10.
[0125]
Thereby, in the marking device 10, when the X-ray film 12 is irradiated with the laser beam LB oscillated by the laser oscillation tube 44 to form the marking pattern MP on the X-ray film 12, the laser beam LB having a stable output intensity. Is irradiated on the X-ray film 12, so that high-quality dots can be formed on the X-ray film 12, whereby a highly visible marking pattern MP can be recorded.
[0126]
The present embodiment described above does not limit the configuration of the present invention. For example, in the present embodiment, CO is used as the laser oscillation means. ₂ Although the laser oscillating tube 44 that oscillates the laser has been described, the laser oscillating means is not limited to this, and any conventionally known laser beam emitting device such as a YAG laser can be applied.
[0127]
In the present embodiment, the time T from the start of the oscillation of the laser beam LB by the laser oscillation tube 44 to the stabilization of the output of the laser beam LB. ₀ However, the start of the processing of the X-ray film 12 is not limited to this.
[0128]
For example, the conveyance process of the X-ray film 12 may be started in anticipation of the time from when the conveyance of the X-ray film 12 is started until the timing of actually irradiating the laser beam LB is reached. That is, after the oscillation of the laser oscillation tube 44 starts, the time T ₀ However, the X-ray film 12 may be transported (processed) so that the X-ray film 12 is irradiated with the laser beam LB when only the time has elapsed.
[0129]
Also, such time T ₀ May be set by performing test printing on the X-ray film 12 and confirming the visibility of each printed dot.
[0130]
In the present embodiment, the time T ₀ Set this time T ₀ However, according to the present invention, the X-ray film 12 can be irradiated with the laser beam LB at least at the timing when the oscillation output of the laser oscillation tube 44 is stabilized. That's fine.
[0131]
From here, for example, the laser beam LB oscillated and output from the laser oscillating tube 44 is monitored or measured by a sensor, and the X-ray film 12 is processed at a timing when the output of the laser oscillating tube 44 is stabilized based on the monitoring result or measurement result. The processing may be started.
[0132]
Furthermore, in this embodiment, the time T _I The operating state and time T of the marking device 10 ₀ However, the present invention is not limited to this. For example, when the operation of the marking apparatus 10 is managed by a higher-level production management apparatus (production management computer) to which the marking apparatus 10 is connected, laser oscillation is performed. The driving of the tube 44 may be managed together.
[0133]
That is, when the host production management computer manages the operation of the marking device 10 in accordance with the progress of the processing of the X-ray film 12, it manages the oscillation start and oscillation stop of the laser oscillation tube 44 together. Also good.
[0134]
In the present embodiment, when the damper 52 is provided in the lens barrel 48 of the marking head 40 and the laser beam LB is irradiated to the damper 52, the oscillation of the laser oscillation tube 44 is continued. Although the X-ray film 12 is prevented from being unnecessarily irradiated with the laser beam LB, the configuration of the present invention is not limited to this.
[0135]
For example, as shown in FIG. 12A, a mirror 54 for reflecting the laser beam LB is provided on the optical path of the laser beam LB between the laser oscillation tube 44 and the beam deflector 46, and the laser beam LB by the mirror 54 is provided. A damper 56 is provided in the reflection direction of the laser beam. Normally, the laser beam LB is irradiated onto the damper 56 by the mirror 54, and the laser beam LB is incident on the beam deflector 46 in accordance with the marking timing of the X-ray film 12. You may make it do.
[0136]
As a result, there is no heat source in at least the lens barrel 48, and thus cooling of the lens barrel 48 becomes unnecessary. Further, it is not necessary to continuously output a deflection signal to the beam deflector 46 so that the laser beam LB is irradiated onto the damper 56.
[0137]
Further, as shown in FIG. 12B, a damper 58 may be provided outside the lens barrel 48 and at a position outside the irradiation region of the laser beam LB on the X-ray film 12. 48 and the marking head 40 can be prevented from generating heat unnecessarily by the laser beam LB, and since there is no heat source in the lens barrel 48, it is not necessary to cool the lens barrel 48.
[0138]
Further, as shown in FIGS. 13A and 13B, a damper 60 may be provided in the laser control device. At this time, as shown in FIG. 13A, the mirror 54 is arranged between the laser oscillation tube 44 and the beam deflector 46, and the mirror 62 is arranged in the reflection direction of the laser beam LB by the mirror 54. The damper 60 provided in the laser control device 42 may be irradiated with the laser beam LB.
[0139]
Further, as shown in FIG. 13B, a mirror 64 is provided outside the lens barrel 48 at a position outside the irradiation region of the laser beam LB to the X-ray film 12, and this mirror 64 is irradiated with the laser beam LB. By doing so, the laser beam LB may be reflected toward the damper 60 provided in the laser control device 42 and irradiated to the damper 60.
[0140]
In general, a laser power amplifier that generates power for driving the laser oscillation tube 44 is provided in the laser control device 10, and cooling means such as a water cooling system that cools the laser power amplifier is provided.
[0141]
From here, it becomes possible to cool the damper 60 using the cooling means of this laser power amplifier.
[0142]
On the other hand, as described above, in the present invention, the processing start timing of the X-ray film 12 is determined by monitoring the laser beam LB oscillated by the laser oscillation tube 44 or measuring the output of the laser beam LB. There may be.
[0143]
From here, a sensor for monitoring or measuring the oscillation output of the laser oscillation tube 44 is provided in the laser control device 42 instead of the damper 60, or a part of the laser beam LB irradiated to the damper 60 is directed to this sensor. A reflecting half mirror, a mirror that can reflect the laser beam LB irradiated to the damper 60 toward the sensor at an arbitrary timing, and the like can be provided.
[0144]
As a result, the laser control device 42 can monitor or measure the output of the laser oscillation tube 44, and can determine the processing start timing of the X-ray film 12 based on the measurement result.
[0145]
In the above-described embodiment, the X-ray film 12 which is a medical photothermographic material has been described as an example of the photosensitive material. can do.
[0146]
【The invention's effect】
As described above, according to the present invention, when a large number of dots are continuously formed by irradiating a laser beam while conveying a photosensitive material, each dot is formed by a laser beam having a stable output. As a result, individual dots can be formed with high quality and a highly visible marking pattern can be recorded on the photosensitive material. At the same time, production efficiency can be prevented An excellent effect is obtained.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a marking device applied to the present embodiment.
2A is a schematic configuration diagram of an X-ray film applied to the present embodiment, and FIG. 2B is a schematic diagram of an X-ray film on which a marking pattern is formed.
FIG. 3 is a schematic perspective view of a main part in the vicinity of a print roll and a marking head.
FIG. 4 is a diagram showing an outline of a change in output of a laser oscillation tube over time.
5A is a diagram showing a change in the intensity of a laser beam in a state where the output is stable, FIG. 5B is a diagram showing an example of a change in the intensity of the laser beam before the output is stabilized, and FIG. Is a schematic diagram showing an example of a dot array formed in a state where the output of the laser beam is stable, and (D) is a schematic diagram showing an example of a dot array formed before the output of the laser beam is stabilized.
FIG. 6 is a schematic view of a marking head showing a laser beam irradiation position at the time of non-marking.
FIG. 7 is a diagram showing an outline of a change in deflection efficiency with respect to a frequency input as a deflection signal in a beam deflector.
FIG. 8 is a flowchart showing an example of processing when marking processing is performed on an X-ray film.
9 is a flowchart showing an example of a marking process in the laser control apparatus according to the process flow of FIG.
FIG. 10 is a diagram showing an example of processing timing of an X-ray film, driving of a laser oscillation tube, and marking availability with the passage of time.
11A is a diagram showing an example of an operation state of a laser oscillator tube during processing of an X-ray film and an example of a timing of a deflection signal with respect to a marking signal, and FIG. 11B is a laser beam irradiation based on the deflection signal. Schematic showing an example of the change in position, (C) is a schematic diagram of a dot array formed on the X-ray film by the change in the irradiation position of (B).
FIGS. 12A and 12B are schematic views of a marking head showing another example of a laser beam irradiation position at the time of non-marking. FIGS.
FIGS. 13A and 13B are schematic views of the vicinity of the marking head showing an example different from FIGS. 12A and 12B of the laser beam irradiation position at the time of non-marking. FIGS. .
14A is a schematic diagram illustrating an example of appropriate dots, and FIG. 14B is a schematic diagram illustrating an example of inappropriate dots.
15A is a diagram showing an example of an output change when the laser oscillation tube is continuously driven, and FIG. 15B is a diagram showing an example of an output change when the laser oscillation tube is pulse-driven.
[Explanation of symbols]
10 Marking device
12 X-ray film (photosensitive material)
14 Base layer
16 Emulsion layer
20 rolls
26 Suction drum
30 print rolls
38 Winding control device
40 Marking head
42 Laser controller
44 Laser tube (oscillation means)
46 Beam deflector (deflection means)
48 lens barrel
52 Damper

Claims (6)

Forming a marking pattern of characters , symbols, or a plurality of characters and character strings arranged on the photosensitive material by an array of dots formed by irradiating laser light oscillated by laser oscillation means while conveying the photosensitive material A laser marking method,
Prior to irradiation of the laser beam to the photosensitive material, the laser oscillation means starts oscillation of the laser beam,
After the oscillation output of the laser oscillation means is stabilized,
The marking pattern is formed on the photosensitive material by irradiating the photosensitive material while deflecting the laser beam according to the marking pattern by a deflecting unit,
After the conveyance of the photosensitive material after the formation of the marking pattern is stopped, a new time is elapsed until a time set longer than the time from when the laser oscillation means starts oscillation until the oscillation output is stabilized. When the conveyance of the photosensitive material is not started, the laser oscillation by the laser oscillation means is stopped.
Laser marking method characterized by the above. A laser that forms a marking pattern of characters , symbols or a plurality of characters , and a character string in which symbols are arranged on the photosensitive material by a dot array formed by irradiating laser light oscillated by a laser oscillation means while conveying the photosensitive material A marking method,
Start oscillation of laser light by the laser oscillation means,
The photosensitive material is transported at a timing set so that the position on the photosensitive material where the marking pattern is formed reaches the irradiation position of the laser beam in a state where the oscillation output of the laser oscillation means that has started oscillation is stable. the start,
It said deflection Shinano said laser beam to form the marking pattern on the photosensitive material shines RaTeru in accordance with the marking pattern by the deflecting means onto the photosensitive material reaching the irradiation position,
After formation of the marking pattern stops conveyance of the photosensitive material ended, until the oscillation output from the start of oscillation of the laser oscillating means is elapsed time set longer than the time required to stabilize, a new When the conveyance of the photosensitive material is not started, the laser oscillation by the laser oscillation means is stopped.
Laser marking method characterized by the above. 3. The laser marking method according to claim 2, wherein the timing at which conveyance of the photosensitive material is started is a time from the start of oscillation of the laser oscillation means until the output of laser light is stabilized. The timing of starting the conveyance of the photosensitive material is such that the output of the laser beam oscillated by the laser oscillation means is stabilized before the position where the marking pattern of the photosensitive material is formed reaches the irradiation position of the laser beam. The laser marking method according to claim 2, wherein the laser marking means is a time from the start of oscillation . The time that the laser oscillating unit starts the conveyance of the photosensitive material from the start of the oscillation, claim 3 or claim 4, wherein the benzalkonium been preset based on output change of the laser oscillating means The laser marking method described in 1.   3. The laser marking method according to claim 2, wherein the timing of starting the conveyance of the photosensitive material is determined based on the detection result by detecting the laser beam oscillated by the laser oscillation means.

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