JPS6035736B2 - Laser recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laser recording device that records by thermally deforming a recording material with a laser beam, and more specifically, the present invention relates to a laser recording device that records by thermally deforming a recording material using a laser beam, and more specifically, the present invention relates to a laser recording device that records by thermally deforming a recording material using a laser beam. The present invention relates to a laser recording device that prevents laser light from remaining in the optical path of the laser light, thereby preventing scattering of the laser light due to gaseous substances and uniformly irradiating the laser light onto a recording material.

Laser recording materials for recording by being thermally deformed by laser light are known, but many of these materials generate gaseous substances when the recording layer is thermally deformed.

These gaseous substances adhere to the optical element in the optical path of the laser light, causing a problem in that it reduces its transmittance.
In order to solve this problem, a method has been proposed in which a thick protective layer is provided on the recording material, and the protective layer prevents the generation of gaseous substances from the recording layer to the outside. However, a thick protective layer absorbs a large amount of the thermal energy of the laser beam applied to the recording layer, resulting in a decrease in sensitivity as a recording material.
Therefore, as a laser recording material that can be thermally deformed with high sensitivity and can be used in comb devices that require high-speed recording,
Those with thick protective layers are not suitable. On the other hand, it has been discovered that when recording by irradiating laser light onto a recording material that generates gaseous substances during recording, not only does the transmittance of the optical system decrease as described above, but also unevenness occurs in the recording. The cause of this recording unevenness is that gaseous matter generated when the recording layer is thermally deformed by laser light irradiation has already accumulated on the surface of the recording layer, and the laser light is scattered or absorbed by the gaseous matter. This is thought to be because the recording layer is irradiated with a laser beam with an intensity corresponding to the density pattern of the gaseous substance. Laser recording materials that undergo thermal deformation are recording materials in which the presence or absence of recording is determined by a certain threshold energy, so the above-mentioned unevenness in the intensity of the laser light remains.
This results in uneven recording. In particular, when the recording layer of a laser recording material is placed on the lower side facing a space and the laser beam is irradiated from below, there is a strong tendency for gaseous substances to remain on the surface of the recording layer, resulting in uneven recording. It was discovered that. In the case of laser recording, it is necessary to irradiate the recording layer with energy slightly higher than the threshold energy, and applying much more energy than the threshold energy will only result in larger recorded points and lower image quality. Instead, it will also destroy the support. Therefore, in the case of laser recording, it is necessary to maintain the amount of irradiated light within a substantially constant range, and even a slight decrease in the amount of light leads to a decrease in image quality, which is a problem. In addition, as a laser recording device, it is preferable to irradiate the laser beam from below with the recording layer of the recording material on the lower side for the following reason.

1. When the recording layer is placed on the upper side, dust tends to adhere to it.

2. Since the laser and its optical system are usually placed on a strong and heavy surface plate, it is preferable to place it at the bottom in terms of the design of the apparatus.

3. In the case of office equipment such as a COM device, it is preferable that the replacement of recording materials and other operations can be performed at a height above waist level.

Now, in the field of so-called laser processing, devices are used that process a workpiece by sufficiently irradiating the workpiece with laser light to melt and burn it. Since this device thermally removes thick workpieces, it naturally generates a large amount of smoke and flying particles, and these smoke and flying particles adhere to the laser light irradiation optical system. It is known that in order to reduce the transmittance, an air current is formed near the workpiece to forcibly remove smoke, flying particles, etc. Its purpose is to remove a large amount of smoke and flying particles from the irradiation optical system. In the field of laser processing, sufficient laser light is irradiated, so processing will not become impossible due to accumulated smoke. An object of the present invention is to provide a laser recording apparatus that can record evenly on a recording material that generates gaseous substances during recording.

Another object of the present invention is to provide a laser recording device that prevents odor and toxicity caused by gaseous substances generated during recording. A further object of the present invention is to provide a laser recording apparatus that does not contaminate the apparatus with adhesion of gaseous substances even when recording with a recording material that generates gaseous substances during recording. A further object of the present invention is to provide a laser recording device that records evenly on a recording material even when irradiated with a small amount of laser light energy. The present invention provides a laser optical system that irradiates a laser beam from below to a recording layer of a laser recording material in which a recording layer for recording information is disposed facing downward and is thermally deformed when irradiated with a laser beam; A gaseous substance generated from the laser recording material during irradiation with the laser beam emitted from the laser optical system is removed from the laser beam irradiation area by a gas flowing along the recording layer at a temperature of 120 qo or more and 160 qo or less. This is a laser recording device characterized by comprising a removing device. The laser recording material used in the present invention has, for example, a polyethylene terephthalate film as a support and a recording layer thereon, and there are various types of recording layer compositions.

A typical recording layer is one in which a metal layer with high optical density mainly made of a metal such as Bi, Sn, or ln and a light absorption layer mainly made of a compound such as QS or SnS are laminated. A thin protective layer made of a resin composition may be laminated on this recording layer. When such a recording material is irradiated with laser light, the material forming the recording layer in the irradiated area undergoes thermal deformation such as melting or evaporation, and disperses into small spheres within the irradiated area. It may remain behind or stick to the periphery of the irradiated area. As a result, the area irradiated with the laser beam becomes light-transmissive, allowing real-time recording. During the thermal deformation described above, the material forming the recording layer and the material forming the thin protective layer are melted, evaporated, etc., and a portion of the material becomes gaseous and ejects from the recording material. Next, the present invention will be specifically explained using the drawings.

FIG. 1 is a schematic explanatory diagram of an example of the apparatus of the present invention, and FIG. 2 illustrates an example of the scanning direction of the laser beam and the direction of air blowing when recording by scanning the laser beam two-dimensionally. This is a diagram for FIG. 1 is a side view of a recording position in a comb device that performs two-dimensional scanning with a laser beam from below to record on a microfilm, and the laser beam scanning optical system is schematically shown as a block. In FIG. 1, the laser recording material is a microfilm 10, which has a recording layer on a support that is thermally deformed by laser beam irradiation, and is arranged with the recording layer facing downward in the drawing. The microfilm 10 is sent out from a delivery member (not shown), passes through a roller 11, and is then held by a platen 13 that moves two-dimensionally on one plane (while keeping the microfilm 10 in close contact with the bottom side) and released from below. After being recorded by laser light irradiation, roller 1
2 and is wound up by a winding member (not shown). A film suction device 14 at the bottom of the platen 13 is connected to a vacuum pump 16 via a flexible tube 15, and suctions the microfilm 10 to hold it flat. The platen 13 can be moved two-dimensionally while keeping a constant distance from the substrate 17, and the movement is performed by various drive devices. The platen 13 also includes a drive device that moves the microfilm 10 relative to the platen 13. Since known devices can be used for these drive devices, their explanation will be omitted. (Drawings are omitted.) Laser light 21 generated from a laser light source 20 is transmitted to an optical modulator 22.
is modulated in time series according to the video signal by, and then deflected in a one-dimensional direction by a first optical deflector 23,
Furthermore, the second optical deflector 24 deflects the light at different speeds in the perpendicular direction (in contrast to the direction in which it is completely deflected), and the lens system 25 focuses the light onto the recording layer of the recording material 10 . Raster scan the top.

Lenses, mirrors, etc. other than those described above may be used in this optical system. Further, as the laser light source 20, for example, 2W
An acousto-optic optical modulator may be used as the optical modulator 22, a rotating polygon mirror may be used as the first optical deflector, and a carbanometer mirror may be used as the second optical deflector. An example of raster scanning is shown in FIG. In FIG. 2, reference numeral 40 is an example of a scanning line formed as a locus by scanning a laser beam in a part of the microfilm 10, for example, an area corresponding to one frame of the microfissure film. . In this case, the scanning lines 40 are sequentially recorded from the top in the direction of the arrow 41, with the fifth scanning line being recorded halfway. Now, in FIG. 1, air is irradiated from a blower 31 through a nozzle 32 at the same time as the laser beam is irradiated toward an area 30 where the microfilm 10 is irradiated (corresponding to the area where the scanning line 40 is recorded in FIG. 2). When the microfilm 10 is blown, the gaseous substances as mentioned above generated during recording are blown away from the vicinity of the area 30 and removed.

Moreover, if the nozzle 33 connected to the exhaust blower 35 is arranged in the direction in which this gaseous material is blown away, most of the blown gaseous material is sucked in by the nozzle 33, and the exhaust blower 35 is exhausted to the outside of the laser recording device through the At this time, if the gaseous substance has a bad odor or contains a substance harmful to the human body, a device 34 for absorbing the odor or harmful substance may be provided. An example of such a device 34 is a deodorizing device that exhausts air through a deodorizing material (eg, corozanilan or carbon). As shown in the above example, the device for removing gaseous substances from the laser beam irradiation area requires a device that blows air into the laser beam irradiation area or a device that sucks air from the laser beam irradiation area, and preferably includes both. It is.

It is not only preferable to have an air intake device because gaseous matter hardly diffuses into the inside of the laser recording device, but also to make the air discharged outside the laser recording device odorless, harmless, and clean by passing through a deodorizing device or the like. Can be done. In the laser recording device used in the present invention, since the recording layer of the laser recording material is on the lower side, gaseous substances generated by laser beam irradiation do not leave the recording layer because their specific gravity is lighter than air. It stays near the irradiation position of the laser light. Therefore, if the apparatus for removing gaseous substances used in the present invention is not used, for example, when recording the fifth scanning line in FIG. 2, the four previously recorded scanning lines will be recorded. Because the gaseous substances generated during this process remain in the area around the area, the laser beam is irradiated onto the recording layer through the gaseous substances, and the laser beam is irradiated in accordance with the distribution of the gaseous substances. Recording becomes uneven. In particular, since the laser recording material is a dark value material, unevenness in the amount of laser light irradiation extremely reduces the quality of the recorded image. In order to eliminate the accumulation of such gaseous substances, a particularly preferable direction for blowing or inhaling air is opposite to the laser beam scanning direction 41 as shown in FIG. They are a direction 42 of air blowing and a direction 43 of air intake.

In this case, since the gaseous material is always removed in the direction in which recording has already been completed, the laser beam is not irradiated onto the recording layer through the gaseous material. The direction 42 of air blowing and the direction 43 of air intake do not necessarily have to be the directions shown in FIG. It is preferable that the direction is not close to 41. A particularly preferred embodiment of the present invention is to blow hot air. In that case, a heater may be provided in the air blowing device. The high-temperature air is preferably air in the range of about 120°C or more and about 160°C or less, and when exposed to hot air in this temperature range, the laser recording material was recorded by irradiation with a small amount of laser light energy. For example, when laser recording was performed while blowing hot air at 140° C. onto a laser recording material, recording was achieved using 20% less laser light energy than when there was no hot air. There is no such effect when the temperature of the hot air is lower than about 120oo, and when the temperature of the hot air is about 1600
If it is higher than 0, the quality of the laser recording material will change. As described above with reference to the drawings, according to the apparatus of the present invention, it is possible to record evenly even when recording on a laser recording material that generates gaseous substances. By using the device of the present invention, there is no need to provide a thick protective layer on the laser recording material, and therefore the laser recording material can be made highly sensitive.
Furthermore, if the apparatus of the present invention is used, the inside of the laser recording apparatus will not be contaminated with gaseous substances. Furthermore, according to the apparatus of the present invention, odorless and harmless air is discharged outside the laser recording apparatus, so that it does not cause any harm to the operator.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of an example of the apparatus of the present invention, and FIG. 2 is a diagram showing an example of the direction of laser beam scanning and the direction of air blowing. In the drawings, 1 shows a recording material, 2 shows a light source, 23 and 24 are optical deflectors, 30 is a laser light irradiation area, 31 and 35 are blowers, 32 and 33 are nozzles, and 40 is a scanning device. Line 41 is the direction of laser light scanning, and 42 and 43 are the directions of air blowing and air intake, respectively. Figure 1 Figure 2

Claims (1)

[Claims] 1. A laser optical system that irradiates a laser beam from below to the recording layer of a laser recording material in which a recording layer for recording information is disposed facing downward and undergoes thermal deformation when irradiated with a laser beam, and the laser optical system When the temperature of flowing along the recording layer is 120° C. or higher, gaseous substances generated from the laser recording material during irradiation with laser light emitted from
1. A laser recording apparatus comprising: a device for removing a laser beam from an irradiated area with a gas at 60° C. or lower.