JP4526732B2 - Optical recording system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a printing plate for lithographic printing by directly irradiating a high-power laser beam.etcThe present invention relates to an optical recording system for recording an image on a disk.
[0002]
[Prior art]
In a CTP (Computer to Plate) or CTC (Computer to Cylinder) plate making system in the printing field, image information stored in a computer is recorded on a photosensitive plate making material (photosensitive material) using a laser scanner or the like. The printed image is developed to produce a printing plate (plate). According to this system, the intermediate material film for printing for each color in the conventional photoengraving process becomes unnecessary. Therefore, it has been attracting attention as a system having advantages such as cost reduction, rapid processing, and quality improvement.
[0003]
In drawing with a laser beam using light-heat conversion in a CTP or CTC plate making system, the sensitivity of the light-sensitive material is low and the drawing speed is slow. Therefore, it is necessary to record using high output light. Therefore, the outer drum type photosensitive material fixing / recording system wraps a plate with a photosensitive material on the substrate around the outside of the drum, and uses an array of dozens of watt-class semiconductor lasers to produce the photosensitive material. It was mainly done to draw in parallel.
[0004]
[Problems to be solved by the invention]
However, in such a recording method using light-heat conversion, heat escapes to the surrounding medium, so that there is a drawback that effective recording sensitivity is lowered by thermal diffusion as recording is slowly performed by parallel writing. It was. This phenomenon is called “low illumination failure”, and the paper “Hare et al.,“ New Method for Exposure Threshold of Laser Thermal Imaging ”,“ New Method for Exposure Measurement of Laser Thermal Imaging ”. of Imaging Science and Technology Vol. 41, no. 6, Nov. / Dec. 1997, pages 588-593. In particular, when general aluminum is used as the base material, the thermal diffusion is large, so that the recording sensitivity is significantly reduced. There was also an adverse effect that the recorded image was blurred due to thermal diffusion.
[0005]
In order to improve this, Japanese Patent Application Publication No. 10-146996 discloses a method of increasing the effective recording sensitivity by increasing the scanning speed of the laser beam.
Japanese Patent Laid-Open No. 11-254741 shortens the irradiation time of the laser beam at each point on the surface of the photosensitive material by narrowing the shape of the laser beam on the photosensitive material in the main scanning direction to make it flat. And how to increase the effective recording sensitivity.
[0006]
  On the other hand, by using an inner drum type photosensitive material fixing / recording system, a plate having a photosensitive material formed on a substrate is wound around the inside of the drum, and a continuous oscillation high output YAG (Yttrium Aluminum Garnet) laser of about 10 watts or more is used. It was also done to draw on the sensitive material. In this case, AOM (Acousto-OpticRecording is performed by combining an external modulator such as a modulator (acousto-optic modulator) and scanning of a laser beam with a high-speed rotating mirror. According to such an inner drum type photosensitive material fixing / recording method, the effective recording sensitivity can be increased by shortening the irradiation time of the laser beam at each point on the photosensitive material surface. This effect is derived from the necessity of recording at high speed using two light sources, and no further increase in sensitivity has been realized.
[0007]
Therefore, even if an improvement method in the inner drum type photosensitive material fixing / recording system and the outer drum type photosensitive material fixing / recording system as described above is used, a further increase in recording sensitivity is desired.
In view of the above points, the present invention reduces the energy (laser power) required for recording or improves the recording speed by increasing the effective recording sensitivity in recording image information on the photosensitive material. It aims at improving.
[0008]
[Means for Solving the Problems]
  In order to solve the above problems, an optical recording system according to the present invention is an optical recording medium in which a layer containing a photosensitive material for recording an image by irradiating a light beam is formed on a substrate, An optical recording medium having a layer containing material having a thickness of 15 nm or less;The pulse irradiation cycle is 1 μsec or less,A light source that sequentially outputs pulsed light having a duty of 1% or less, a modulation unit that modulates pulsed light output from the light source with an image signal and irradiates the layer including the photosensitive material, and the pulse on the layer including the photosensitive material Scanning means for recording an image by scanning light.
  In another optical recording system according to the present invention, the recording time per pixel is 1 μsec or less, and the period of irradiation with pulsed light for recording one pixel is 1% or less of the recording time per pixel. It is characterized by being.
[0010]
  According to the present invention configured as described above,The pulse irradiation cycle is 1 μsec or less,By using pulsed light having a duty of 1% or less and recording an image on a recording material having a layer containing a photosensitive material having a thickness of 15 nm or less, effective recording sensitivity in optical recording can be improved. OrThe recording time per pixel is 1 μsec or less,By recording an image using pulsed light having a period of 1% or less of the recording time per pixel, the effective recording sensitivity in optical recording can be improved. Therefore, the total energy required for recording can be reduced, the recording speed can be improved, and productivity can be improved. Furthermore, by reducing the energy for recording, blur of the recorded image due to thermal diffusion can be improved and sharpness can be improved.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same reference number is attached | subjected to the same component and description is abbreviate | omitted.
An optical recording system according to an embodiment of the present invention will be described with reference to FIGS. The optical recording system according to this embodiment has a loss when energy is supplied to a light-sensitive material by exposing the light-sensitive material (a layer including a light-sensitive material and a light-sensitive layer) with an ultrathin film using short pulse light. In order to effectively use the absorbed light energy.
[0012]
FIG. 1 is a diagram showing in principle the optical recording apparatus used in the optical recording system according to the present embodiment. This optical recording apparatus has a passive mode-locked laser 1 for generating pulsed laser light. A synchronization signal synchronized with each pulse light is extracted from the passive mode-locked laser 1 and applied to the image signal processing circuit 2. The image signal processing circuit 2 creates a modulation signal for modulating the pulsed light based on the image signal, and supplies the modulation signal to the optical shutter 3 in synchronization with the synchronization signal. The optical shutter 3 modulates the pulsed light generated by the passive mode-locked laser 1 in accordance with this modulation signal.
[0013]
The pulsed light modulated by the optical shutter 3 is reflected by a rotating mirror 5 installed inside the drum 4 and is applied to a plate 6 wound around the inner surface of the drum 4. The plate 6 includes a base material 7 made of aluminum or the like and a photosensitive material 8 formed on the base material 7, and an overcoat (cover) layer may be further provided on the photosensitive material 8. . When the rotating mirror 5 rotates at a predetermined rotation speed, the reflected light scans the surface of the photosensitive material 8 and an image is recorded.
[0014]
FIG. 2 shows the waveform of a pulsed laser beam generated from a passive mode-locked laser. In order to shorten the recording time of the entire image, it is desirable that the recording time per pixel (hereinafter referred to as 1 pixel forming time) is 1 μsec or less. More preferably, the time for forming one pixel is 200 nsec or less. In the present embodiment, one pixel formation time is 20 nsec (frequency is 50 MHz). Note that when there are only two gradations “1” or “0” in each pixel, the recording information of one pixel corresponds to one bit of the image signal.
[0015]
Conventionally, laser light was continuously irradiated over the entire pixel formation time. In contrast, in the present invention, in order to reduce the total power of the laser and improve the effective recording sensitivity in optical recording, recording is performed using short pulse light with a duty of 50% or less. The short pulse light may be a single pulse light output from a single laser, or may be a plurality of pulse lights output from a plurality of lasers arranged in a predetermined direction. . Further, the number of laser pulses in a period for recording one pixel may be one or plural. For example, when one pixel formation time is 20 ns, exposure may be performed with one laser pulse having a pulse width of 10 ns, or laser light having a pulse width of 5 ns may be turned on / off twice for 2 times. Exposure may be performed with a single laser pulse.
[0016]
By irradiating the laser beam in a pulse manner in this way, the total power of the laser can be reduced. As a result, it becomes possible to use a laser having a smaller rated output than the conventional one. This is because the rated output of the laser is mainly determined by the steady output power, so that the instantaneous output of the laser can be made larger than the rated output by reducing the duty. For example, if the duty of the laser beam is 50%, the instantaneous output of the laser can theoretically be about twice the rated output. On the other hand, the effective recording sensitivity in optical recording is improved by shortening the irradiation time (exposure time) of the laser beam in each pixel as described above. For these reasons, it is effective to use pulsed light in optical recording of image information.
[0017]
The passive mode-locked laser can generate a short pulse light of several p seconds (10 p seconds or less) to 1 n seconds. In order to further increase the effective recording sensitivity in optical recording using this, it is conceivable to further reduce the duty of the laser beam. For example, the laser pulse irradiation period is set to 200 p seconds (1% of one pixel formation time 20 nsec) or less, and the laser light duty is set to 1% or less. In the present embodiment, the laser pulse irradiation period during one pixel formation time is 100 ps × 2 times, and for this purpose, a laser pulse with a duty of 1% is used.
[0018]
FIG. 3 is a diagram schematically showing a recording material used in the optical recording system according to the present embodiment. This recording material is obtained by providing a photosensitive material (photosensitive layer) having a thickness of 1 nm or more, more preferably 5 nm or more and 15 nm or less, more preferably 10 nm or less on a substrate. As a material of the substrate, a metal such as aluminum (thermal conductivity: 2.37 J / sec · cm · K) or a synthetic resin such as PET (polyethylene terephthalate, thermal conductivity: 0.0028 J / sec · cm · K) is used. Can be used. An overcoat (cover) layer of PET or the like may be further provided on the photosensitive layer for heat insulation and protection.
[0019]
In general, when the total amount of the photosensitive material is large, the sensitivity depends on the amount of the photosensitive material. For example, in the recording in the thermal mode, the energy required to heat the photosensitive material increases, so that the sensitivity is limited by the amount of the photosensitive material. Therefore, in the present invention, the light absorption layer is made ultrathin so as to effectively use the absorbed light energy.
[0020]
In the conventional thermal recording, the exposure energy is increased by using a long pulse light of about several hundreds of nanoseconds to 10 μsec. More than 50% of the maximum time required for recording per pixel, usually 90% or more. I spent a lot of time recording. As described above, when the photosensitive material is heated over time, energy loss due to thermal diffusion after the pulsed light is converted into heat is large. Therefore, even if the heating energy of the light-sensitive material is suppressed by reducing the thickness of the light-sensitive material, energy loss due to thermal diffusion occurs further, so the effect of thinning the light-sensitive material is small. However, as in the optical recording system according to the present embodiment, if the exposure time is shortened using short pulse light, the degree of thermal diffusion after the pulse light is converted into heat is reduced and can be ignored. Therefore, the effect of suppressing the energy required for heating the photosensitive material by making the photosensitive material thin is remarkable. This effect can be confirmed if the photosensitive layer is about 2 atomic layers (thickness: about 1 nm), but considering the wear resistance as a CTP plate, the thickness of the photosensitive layer will be about 5 nm.
[0021]
A recording material composed of a substrate, a photosensitive material (photosensitive layer) and a cover layer shown in FIG. In this simulation, metallic titanium was used for the photosensitive layer, and the thickness of the layer was changed in the range of 3 nm to 30 nm. Further, PET (thermal conductivity: 0.0028 J / sec · cm · K) was used for the substrate. Furthermore, a cover layer made of PET was provided on the photosensitive layer for heat insulation. Assuming that 50% of the irradiated laser light is absorbed by the titanium photosensitive layer, the maximum temperature reached by the photosensitive material was calculated under the following two different laser pulse irradiation conditions.
(1) Long pulse width exposure (power density 30 kW / cm², Pulse width 7μs)
(2) Short pulse width exposure (power density 30 GW / cm², Pulse width 7p seconds)
However, the total energy amount of one laser pulse is constant. FIG. 4 shows the waveform of the pulsed laser beam under the irradiation condition (2).
[0022]
The result of this simulation is shown in FIG. In FIG. 5, the horizontal axis represents the thickness of the titanium photosensitive layer, and the vertical axis represents the maximum temperature rise of the photosensitive material.
As shown in FIG. 5, in the case of the long pulse width exposure under the irradiation condition (1), the rising temperature does not depend on the thickness of the photosensitive layer and is almost constant. This is because not only the photosensitive layer but also the surrounding layers are heated by the diffusion of heat.
[0023]
In contrast, in the case of short pulse width exposure under the irradiation condition (2), a high temperature exceeding 10,000 degrees is obtained regardless of the thickness of the photosensitive layer, and the temperature increases as the photosensitive layer thickness is reduced. is doing. This is remarkable in the range where the thickness of the photosensitive layer is 15 nm or less. In particular, in the range where the thickness of the photosensitive layer is 10 nm or less, the thickness is 1.5 to 9 times compared to the case where the thickness is 30 nm. A temperature increase of about double is observed. The reason for this is thought to be that during short pulse width exposure, the effect of energy loss due to thermal diffusion is small, so reducing the thickness of the photosensitive layer reduces the heat capacity of the photosensitive layer itself, thereby increasing the temperature.
[0024]
FIG. 6 shows the relationship between the energy required to raise the temperature of various types of metal thin films having a thickness of 10 nm to the melting point and the heat of fusion. The horizontal axis indicates the energy per unit area necessary for heating to the melting point, and the vertical axis indicates the heat of fusion per unit area.
For example, in order to record in the ablation mode in printing, energy for heating or melting the metal that is the material of the photosensitive layer is required, but as shown in FIG. If the thickness is 10 nm or less, these energies are 10 mJ / cm.²The following will be sufficient.
[0025]
Therefore, by carrying out short pulse width exposure on the photosensitive layer thinned to 10 nm, it is several mJ / cm more sensitive than the conventional one.²Recording in the thermal mode having the sensitivity of 1 is possible. By increasing the recording sensitivity in this way, it is possible to improve the recording speed and to employ a lower energy exposure laser, and thus it is possible to reduce the cost.
[0026]
In the above example, a metal is used for the photosensitive layer, but in addition to this, titanium oxide (TiO 2) is used._X) Or titanium nitride (TiN)_XIt is also possible to use an oxide or nitride such as) or an organic light absorption layer.
Further, when the thickness of the photosensitive layer is 10 nm or less, the influence of thermal diffusion in a short time cannot be ignored. In such a case, by using a synthetic resin having a low thermal conductivity for the substrate, thermal diffusion can be suppressed and the temperature of the photosensitive layer can be increased efficiently. In the present embodiment, PET is exemplified as the synthetic resin used for the substrate and the cover layer, but various other synthetic resin materials can be used.
[0027]
Next, an optical recording apparatus used in the optical recording system according to an embodiment of the present invention will be described in detail with reference to FIGS.
FIG. 7 is a perspective view showing a part of the inner drum type optical recording apparatus according to the present embodiment. The inner drum type optical recording apparatus 21 has a drum 25 whose inner surface is cylindrical. Inside the drum 25, a plate 6 having a photosensitive material formed on a base material such as aluminum is fixed. The drum 25 is driven by the drum moving mechanism 27 and moves in the direction along the drum axis (Z direction in the drawing).
[0028]
The optical system 22 of the optical recording device 21 includes a passive mode-locked laser 1, an optical shutter 3, and a rotating mirror 5. Further, a condensing lens 23 may be provided. The pulsed light generated by the passive mode-locked laser 1 is modulated by an optical shutter 3 that opens and closes according to an image signal. The pulsed light that has passed through the optical shutter 3 is focused by the condenser lens 23. The focal point of focusing is adjusted so as to be located in the vicinity of the surface of the photosensitive material of the plate 6.
[0029]
The pulsed light exiting the condenser lens 23 is incident on the rotating mirror 5. The surface of the rotating mirror 5 on the condenser lens 23 side is inclined 45 ° with respect to the axis. The laser light hitting this surface enters the surface of the photosensitive material of the plate 6 almost perpendicularly. The rotating mirror 5 is driven by a motor 24 and rotates at a high speed around the same axis as the drum axis. The position at which the laser beam strikes the photosensitive material is changed by the rotation of the rotating mirror 5, and the laser beam is scanned in the main scanning direction (X direction in the figure). Since the plate 6 moves in the direction along the drum axis (Z direction in the figure), the laser light is scanned two-dimensionally in the main scanning direction and the sub-scanning direction.
[0030]
FIG. 8 is a diagram showing in principle the passive mode-locked laser used in the optical recording apparatus shown in FIG. The passive mode-locked laser 1 includes a laser medium 31 that amplifies laser light using an inversion distribution. As the laser medium 31, yttrium aluminum garnet (Y_ThreeAl_FiveO₁₂Nd: YAG medium using a crystal doped with neodymium (Nd) as an impurity can be used. Alternatively, instead of the Nd: YAG medium, Nd: YLF (YLiF_Four) Medium and Nd: YVO_FourA medium or the like may be used.
[0031]
Two mirrors 32 and 33 that reflect light amplified by the laser medium are placed on both sides of the laser medium 31. Furthermore, a mirror 34 that reflects light between the mirror 32 and the saturable absorber 35 and an output mirror 36 that reflects part of the light incident from the mirror 33 and emits part of the light are provided. Thereby, the passive mode-locked laser 1 oscillates in a plurality of modes having different frequencies. The saturable absorber 35 absorbs a part of the light incident from the mirror 34 to align the phases of the plurality of oscillation modes.
[0032]
In addition to this, various optical recording apparatuses can be used in the optical recording system according to the present embodiment.
FIG. 9 shows a first modification of the optical recording apparatus used in the optical recording system according to the present embodiment. In this optical recording apparatus, instead of taking out a synchronizing signal synchronized with each pulsed light from the passive mode-locked laser 1, the pulsed light output from the passive mode-locked laser 1 is split by the beam splitter 9 and a part of it is optically reflected. By entering the detector 10, a synchronization signal is obtained. Other points are the same as those of the optical recording apparatus shown in FIG.
[0033]
FIG. 10 shows a second modification of the optical recording apparatus used in the optical recording system according to the present embodiment. This optical recording apparatus uses an active mode-locked laser 11 instead of a passive mode-locked laser. Since the active mode-locked laser 11 can output pulsed light in synchronization with an externally applied synchronizing signal, the image signal processing circuit 12 creates a synchronizing signal and applies it to the active mode-locked laser 11. Thus, desired pulsed light can be obtained.
[0034]
FIG. 11 is a diagram showing in principle the active mode-locked laser used in the optical recording apparatus shown in FIG. The active mode-locked laser 11 uses, for example, an Nd: YAG medium as the laser medium 31. Two mirrors 32 and 33 that reflect light amplified by the laser medium are placed on both sides of the laser medium 31. Furthermore, a mirror 34 that reflects light incident from the mirror 32 via an AOM (acousto-optic modulator) 37 and an output mirror 36 that reflects part of the light incident from the mirror 33 and emits part of the light are provided. It has been. Thereby, the active mode-locked laser 11 oscillates in a plurality of modes having different frequencies. The AOM 37 aligns the phases of the plurality of oscillation modes by modulating the incident light according to the modulation signal output from the modulation signal generator 38.
[0035]
FIG. 12 shows a third modification of the optical recording apparatus used in the optical recording system according to the present embodiment. This optical recording apparatus uses a Q switch laser 13. Since the Q switch laser 13 can output pulsed light in synchronization with a synchronization signal applied from the outside, the image signal processing circuit 12 creates a synchronization signal and applies it to the Q switch laser 13. A desired pulsed light can be obtained. A solid state laser or fiber laser by Q switching can generate a short pulse light of several nanoseconds to several tens of nanoseconds. For example, the irradiation period of a laser pulse in one pixel formation time of 20 nanoseconds is 8 nanoseconds. This corresponds to 40% of one pixel formation time.
[0036]
FIG. 13 is a diagram showing in principle the Q-switched laser used in the optical recording apparatus shown in FIG. Regarding the laser medium 41 of the Q-switched laser 13, Nd: YAG medium, Nd: YLF medium, Nd: YVO are used as solid laser media._FourVarious media such as media can be used. On both sides of the laser medium 41, a total reflection mirror 42 and a partial reflection mirror 43 that reflect light amplified by the laser medium are placed. Thereby, the Q switch laser 13 oscillates in a plurality of modes having different frequencies. Here, a modulator 44 is provided between the laser medium 41 and the mirror 43 as means for adjusting the loss or gain of the laser light. The modulator 44 is composed of, for example, an AOM (acousto-optic modulator), and modulates incident light according to the modulation signal input from the modulation signal generator 45, thereby aligning the phases of a plurality of oscillation modes. Various modulators such as an EO (Electro-Optics) modulator can be used as the modulator 44 in addition to the AOM.
[0037]
In addition, a fiber laser using an optical fiber to which Nd, Yb (ytterbium) or the like is added as a laser medium can be used with the same configuration. Further, a gain switch laser using a semiconductor as a gain adjusting means may be used. In a normal current injection type semiconductor laser, it is possible to generate pulsed light by gain switching that modulates the injection current. The gain switch laser can generate a short pulse light of several tens of p seconds to several n seconds.
[0038]
Next, a fourth modification of the optical recording device used in the optical recording system according to the present embodiment will be described with reference to FIG. As shown in FIG. 14, this optical recording apparatus employs an outer drum type photosensitive material fixing / recording system, and is otherwise the same as the optical recording apparatus described above. Here, an example using a passive mode-locked laser will be described.
[0039]
The outer drum type optical recording apparatus 51 has a drum 55 whose outer surface is cylindrical. A plate 6 having a photosensitive material formed on a base material such as aluminum is fixed to the outside of the drum 55. The drum 55 is driven by a rotation mechanism 57 including a motor, a speed reducer, and the like, and rotates in a direction along the circumference of the drum (X direction in the drawing).
[0040]
Each of the two series of optical systems 52 includes a passive mode-locked laser 1 and an optical shutter 3. Further, a condensing lens 23 may be provided. The pulsed light generated by the passive mode-locked laser 1 is modulated by an optical shutter 3 that opens and closes according to an image signal. The pulsed light that has passed through the optical shutter 3 is focused by the condenser lens 23. The focal point of focusing is adjusted so as to be located in the vicinity of the surface of the photosensitive material of the plate 6. The pulsed light exiting the condenser lens 23 enters the surface of the photosensitive material of the plate 6 almost perpendicularly.
[0041]
  During image recording, the drum 55 rotates at a high speed in the direction along the circumference of the drum (X direction in the figure), and the entire optical system 52 is parallel to the axis of the drum (Z direction in the figure). Moving. Accordingly, the laser light is two-dimensionally scanned in the main scanning direction and the sub-scanning direction. For scanning in the Z direction, it is also possible to use an optical scanner such as a polygon mirror or a galvanometer mirror.The optical recording system as described above can be widely applied to the production of printed circuit boards and optical disk memories in addition to the high-speed CTP without processing.
[0042]
【The invention's effect】
As described above, according to the present invention, by performing a short pulse width exposure on a thinned photosensitive material, the sensitivity is dramatically improved, a higher-speed image formation is possible, and the printing process is improved. It can be shortened. Also, by reducing the energy for recording, blur of the recorded image due to thermal diffusion can be improved and sharpness can be improved.
[0043]
In addition, by shortening the laser light pulse, it becomes possible to use a laser with a small rated output, so that the cost of the laser light source can be reduced. For example, generation of short pulse light in a solid-state laser or fiber laser by passive mode locking can be easily realized by inserting a saturable absorber. Therefore, there is a great advantage that a low-power laser can be adopted by shortening the laser beam.
[Brief description of the drawings]
FIG. 1 is a diagram showing in principle an optical recording apparatus used in an optical recording system according to an embodiment of the present invention.
FIG. 2 is a diagram showing a waveform of a pulsed laser beam generated from the passive mode-locked laser shown in FIG.
FIG. 3 is a schematic view showing a recording material used in an optical recording system according to an embodiment of the present invention.
FIG. 4 is a diagram illustrating a waveform of a pulsed laser beam used when a simulation of an optical recording system according to an embodiment of the present invention is performed.
FIG. 5 is a diagram showing simulation results for an optical recording system according to an embodiment of the present invention.
FIG. 6 is a diagram showing a relationship between energy necessary for heating a metal thin film to a melting point and heat of fusion.
FIG. 7 is a perspective view showing a part of an inner drum type optical recording apparatus used in the optical recording system according to an embodiment of the present invention.
FIG. 8 is a diagram showing in principle the passive mode-locked laser of FIG.
FIG. 9 is a first modification of an optical recording apparatus used in an optical recording system according to an embodiment of the present invention.
FIG. 10 is a second modification of the optical recording apparatus used in the optical recording system according to the embodiment of the present invention.
FIG. 11 is a view showing in principle the active mode-locked laser of FIG.
FIG. 12 is a third modification of the optical recording apparatus used in the optical recording system according to the embodiment of the present invention.
13 is a view showing in principle the Q-switched laser shown in FIG.
FIG. 14 is a fourth modification of the optical recording apparatus used in the optical recording system according to the embodiment of the present invention.
[Explanation of symbols]
1 Passive mode-locked laser
2, 12 Image signal processing circuit
3 Optical shutter
4, 25, 55 drums
5 Rotating mirror
6 plates
7 Base material
8 Sensitive materials
9 Beam splitter
10 Light detector
11 Active mode-locked laser
13 Q-switched laser
21 Inner drum type optical recording device
22, 52 Optical system
23 Condensing lens
24 motor
27 Drum moving mechanism
31 Laser medium
32, 33, 34 Mirror
35 Supersaturated absorber
36 Output mirror
37 AOM (acousto-optic modulator)
38 Modulation signal generator
42 Total reflection mirror
43 Partial reflection mirror
44 Loss modulator
51 Optical recording device of outer drum type
57 Rotating mechanism

Claims (8)

An optical recording medium in which a layer containing a photosensitive material for recording an image by irradiating a light beam is formed on a substrate, the thickness of the layer containing the photosensitive material being 15 nm or less;
A light source that sequentially outputs pulsed light having a pulse irradiation period of 1 μsec or less and a duty of 1% or less;
Modulation means for modulating the pulsed light output from the light source with an image signal and irradiating the layer containing the photosensitive material;
Scanning means for recording an image by scanning the pulsed light on the layer containing the photosensitive material;
An optical recording system comprising: An optical recording medium in which a layer containing a photosensitive material for recording an image by irradiating a light beam is formed on a substrate, the thickness of the layer containing the photosensitive material being 15 nm or less;
A light source that sequentially outputs pulsed light ;
Modulation means for modulating the pulsed light output from the light source with an image signal and irradiating the layer containing the photosensitive material;
Scanning means for recording an image by scanning the pulsed light on the layer containing the photosensitive material;
Equipped with,
1 recording time per pixel is not more than 1μ seconds, an optical recording system is time for irradiating pulse light, characterized in der Rukoto less than 1% of the recording time per pixel to record one pixel.   The optical recording system according to claim 2, wherein the light source outputs a single or a plurality of pulse lights to record one pixel. The pulse width of the pulse light in which the light source is output is less than or equal to 10p sec, claim 1-3 optical recording system according to any one of. It said light source is a mode-locked laser and Q is one of the switched laser and the gain-switched laser according to claim 1-4 optical recording system according to any one of. 6. The optical recording system according to claim 5 , wherein the mode-locked laser outputs a synchronization signal used when modulating and outputting pulsed light to the modulating means. Wherein the layer containing the light-sensitive material, the light - is used heat-exchange reaction, an optical recording system of any one of claims 1-6. The optical recording system of the layer substrate is formed, it is formed of a material other than metal, according to any one of claims 1-7 including a photosensitive material in the optical recording medium.

Images