JP2012056134A - Image drawing control device, laser beam irradiation apparatus, image drawing control method, image drawing control program, and recording medium with the control program recorded thereon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image drawing control device, laser beam irradiation apparatus, image drawing control method, image drawing control program that can draw accurate images on a medium in a brief time by properly controlling an irradiation energy of laser beam which the medium receives, and to provide a recording medium with the image drawing control program recorded thereon.SOLUTION: The image drawing control device controls an image drawing device drawing a target to be drawn by irradiating the medium with laser beams. The image drawing control device includes: a stroke information generation means for generating stroke information indicative of a plurality of strokes for drawing the target to be drawn based on shape information representing a shape of the target to be drawn; a laser adjusting means for generating an output of the laser beam, a scanning speed, or a standby time based on the stroke information generated by the stroke information generation means and a lapse time between the strokes; and an image drawing instruction generation means for generating an image drawing instruction for controlling the image drawing device based on the stroke information the stroke information generation means generates, the output of the laser beam, scanning speed, or standby time the laser adjusting means generates.

Description

  The present invention relates to a drawing control device, a laser irradiation device, a drawing control method, a drawing control program, and a recording medium recording the same.

  Laser irradiation devices (laser markers or laser marking devices) that use technology to write letters, numbers, symbols, etc. on a medium by irradiating a medium such as metal, plastic, or thermal paper with laser light are heated. ing.

  By irradiating a laser beam using a gas laser, a solid-state laser, a liquid laser, a semiconductor laser, or the like as a laser light source of the laser irradiation apparatus, characters or the like can be written on a medium such as metal, plastic, or thermal paper.

  Metals and plastics are drawn by shaving or scorching by irradiating with laser light and heating. On the other hand, thermal paper has the property of being discolored by heat, and drawing is performed when the recording layer is colored by heating with laser light irradiation.

  Since thermal paper is easier to handle than metal and plastic media, for example, it is widely used as a medium for drawing the destination and name of an article in the field of logistics and the like.

  And rewritable paper that can be written and erased even with such thermal paper has appeared.

  FIG. 1 is a diagram for explaining the principle of color development / decoloration of a thermal rewritable medium.

  The thermal rewritable medium includes a recording layer whose color tone reversibly changes between a transparent state and a colored state by heat. This recording layer is composed of a leuco dye, which is an organic low-molecular substance, and a reversible developer (hereinafter referred to as a developer).

  First, when the temperature of the recording layer in the decolored state (A) shown in FIG. 1 is raised, the leuco dye and the developer are melted and mixed at the melting temperature T2, and color development occurs and melt color development occurs. It will be in a state (B). When rapidly cooled from the melt color state (B), the color state can be lowered to room temperature, and the color state is stabilized and becomes a fixed color state (C). Whether or not this colored state can be obtained depends on the rate of temperature decrease from the molten state. In slow cooling, the color disappears during the temperature decreasing process, and is the same as the initial color erased state (A) or the color developed state by rapid cooling ( The density is relatively lower than in C).

  On the other hand, when the temperature is raised again from the coloring state (C), the color disappears at a temperature T1 lower than the coloring temperature (D to E), and when the temperature is lowered from this state, the same color erasing state (A) as the initial state. Return to.

  The colored state (C) obtained by quenching from the molten state is a state in which the leuco dye and the developer are mixed in a state in which molecules can contact each other, and this forms a solid state. Many. In this state, the molten mixture (color mixture) of the leuco dye and the developer is crystallized to maintain the color development, and it is considered that the color development is stabilized by the formation of this structure. On the other hand, the decolored state is a state in which both phases are separated. This state is a state in which molecules of at least one compound aggregate to form a domain or crystallize, and the leuco dye and the developer are separated and stabilized by aggregation or crystallization. It is believed that there is. In many cases, the color developer is crystallized as a result of phase separation between the two, thereby causing more complete color erasure.

  If the temperature of the recording layer is repeatedly raised to a temperature T3 that is equal to or higher than the melting temperature T2, an erasing defect that cannot be erased even when heated to the erasing temperature may occur. This is presumably because the developer undergoes thermal decomposition and is difficult to aggregate or crystallize and separate from the leuco dye. In order to suppress the deterioration of the thermoreversible recording medium due to repetition, the deterioration of the medium due to repeated recording and erasing can be suppressed by reducing the difference between the melting temperature T2 and the temperature T3 when heating the thermoreversible recording medium.

  Such a thermal rewritable medium is widely used, for example, in the field of physical distribution and the like, and various contrivances have been made for a method of recording (drawing).

  For example, when drawing the first and second lines adjacent to each other, the recording fading due to the mutual interference between the residual heat of the first line drawn first and the heat at the time of drawing the second line. In order to suppress the phenomenon, it has been proposed to control the drawing time or overlapping width from the drawing start point of the first line to the drawing end point of the second line (see, for example, Patent Document 1).

  As described above, the thermal rewritable medium has the property that the color development is erased by heat at a certain temperature and the color develops when further heated.

  However, if an excessive heat load is applied by laser irradiation (overheating), the thermal rewritable medium is altered, and the deterioration of the medium such as the life of the medium is shortened or the erasure cannot be performed easily. On the other hand, when the heating is insufficient, the thermal rewritable medium does not sufficiently develop color.

  In addition, in the case of a medium such as plastic or metal, if an excessive heat load is applied by laser irradiation (too much heating), the heated part will be scraped off more than necessary, and if the heating is insufficient, the thickness will be insufficient. It becomes thin.

  Incidentally, in order to accurately draw a bitmap image on a thermal rewritable medium or a medium such as plastic or metal, it is necessary to appropriately control the irradiation energy (laser output) of the laser.

  Since the laser irradiation range is very small, the laser is scanned when drawing a line. When drawing a wider (thick) diagram than a line drawn in one scan or a bitmap image such as a fill, it is necessary to scan the laser repeatedly while shifting the laser in the width direction. There is.

  When scanning the laser while shifting in the width direction in this way, the periphery of the line drawn one line before is heated by the laser irradiation for drawing the line drawn one line before, and heat remains. is doing.

  For this reason, if the laser irradiation range is shifted in the width direction while the laser output is kept constant and a line is drawn adjacent to the line drawn one line before, the medium will be removed by the remaining heat. Since it was heated excessively, there was a problem that accurate drawing could not be performed due to an excessive heat load.

  Therefore, the present invention provides a drawing control apparatus, a laser irradiation apparatus, a drawing control method, a drawing control program, which can accurately perform drawing on a medium in a short time by appropriately controlling the irradiation energy of the laser received by the medium, And it aims at providing the recording medium which recorded this.

  A drawing control apparatus according to an aspect of an embodiment of the present invention is a drawing control apparatus that controls a drawing apparatus that draws a drawing target by irradiating a medium with a laser, and is based on shape information that represents the shape of the drawing target. , Based on stroke information generating means for generating stroke information representing a plurality of strokes for drawing the drawing target, stroke information generated by the stroke information generating means, and an elapsed time between strokes. Based on the laser adjustment means for generating the output, the scanning speed, or the standby time, the stroke information generated by the stroke information generation means, the output of the laser, the scanning speed, or the standby time generated by the laser adjustment means, Drawing command generation means for generating a drawing command for controlling the drawing device.

  Further, the laser adjustment unit includes a determination unit that determines whether there is another stroke that is adjacent to one stroke and has a drawing order earlier than the one stroke, and drawing from the drawing by the other stroke. A calculation unit that calculates an elapsed time until the output, a determination result of the determination unit, and an output determination unit that determines the output of the laser based on the elapsed time calculated by the calculation unit.

  The output determination unit may lower the output of the laser as the elapsed time is shorter.

  Further, the laser adjustment unit includes a determination unit that determines whether there is another stroke that is adjacent to one stroke and has a drawing order earlier than the one stroke, and drawing from the drawing by the other stroke. And a speed setting unit for setting the scanning speed of the laser based on the determination result of the determination unit and the elapsed time calculated by the calculation unit.

  The speed setting unit may increase the scanning speed of the laser as the elapsed time is shorter.

  The stroke information generating unit further includes a stroke piece generating unit that divides the stroke represented by the stroke information generated by the stroke information into stroke pieces of a predetermined length, and the determination unit is configured to convert one stroke piece included in the one stroke. It is determined whether or not there is a stroke piece included in another stroke that is adjacent and earlier in the drawing order than the one stroke piece, and the calculation unit performs the drawing from the other stroke piece to the drawing by the one stroke piece. The elapsed time may be calculated.

  The laser adjustment unit may further include a standby time setting unit that sets a standby time between strokes according to a determination result of the determination unit.

  The standby time setting unit may set the standby time longer as the elapsed time calculated by the calculation unit is shorter.

  A laser irradiation apparatus according to an embodiment of the present invention includes a laser oscillator that irradiates a laser, a direction control mirror that controls an irradiation direction of the laser irradiated by the laser oscillator, and a direction control that drives the direction control mirror. A drawing control apparatus according to any one of the above, wherein the drawing control device performs control of irradiation output of the laser oscillator and drive control of the direction control motor based on the drawing command.

  A drawing control method according to an aspect of an embodiment of the present invention is a drawing control method in which a computer controls a drawing apparatus that draws a drawing target by irradiating a medium with a laser, and the computer controls the shape of the drawing target. A stroke information generation step for generating stroke information representing a plurality of strokes for drawing the drawing target, stroke information generated in the stroke information generation step, and an elapsed time between strokes, Based on the above, the laser adjustment process for generating the laser output, the scanning speed or the standby time, the stroke information generated in the stroke information generation process, the laser output and the scanning speed generated in the laser adjustment process Or a drawing command generation step of generating a drawing command for controlling the drawing device based on the waiting time.

  A drawing control program according to an aspect of an embodiment of the present invention is a drawing control program for causing a computer to execute a drawing control process for controlling a drawing apparatus that draws a drawing target by irradiating a laser to a medium. Stroke information generating means for generating stroke information representing a plurality of strokes for drawing the drawing object based on shape information representing the shape of the drawing object; stroke information generated by the stroke information generating means; Based on the elapsed time between strokes, the laser adjusting means for generating the laser output, the scanning speed, or the standby time, the stroke information generated by the stroke information generating means, and the laser generated by the laser adjusting means Drawing for controlling the drawing device based on output, scanning speed or standby time To function as a drawing command generating means for generating a decree.

  A recording medium on which a drawing control program according to an aspect of the present invention is recorded is a recording medium on which the drawing control program is recorded.

  A drawing control apparatus, a laser irradiation apparatus, a drawing control method, a drawing control program, and a recording in which this is recorded, capable of performing accurate drawing on the medium in a short time by appropriately controlling the laser irradiation energy received by the medium Media can be provided.

It is a figure for demonstrating the principle of coloring / decoloring of a thermal rewritable medium. It is a figure for demonstrating the problem at the time of drawing by a drawing control apparatus. In the drawing control apparatus and drawing control method of this invention, it is a figure for demonstrating the basic view of the calculation method of the calorie | heat amount given to a medium in order to perform accurate drawing on a medium in a short time. 3 is a diagram illustrating an example of a hardware configuration of a laser marking apparatus including the drawing control apparatus according to Embodiment 1. FIG. 2 is a diagram illustrating an example of a hardware configuration of a drawing control apparatus 20 according to Embodiment 1. FIG. FIG. 3 is a functional block diagram of the drawing control apparatus 20 according to the first embodiment. It is a figure which shows the method in which the stroke information generation part 202 of the drawing control apparatus 20 of Embodiment 1 produces | generates stroke information from the bitmap image data showing drawing object. 4 is a flowchart illustrating a drawing control process executed by the drawing control apparatus 20 according to the first embodiment. FIG. 3 is a diagram illustrating a part of a graphic drawn by a drawing control process executed by the drawing control apparatus 20 according to the first embodiment. It is a figure for demonstrating the integration process of a drawing command. It is a figure which shows an example of the drawing command which the drawing control apparatus 20 of Embodiment 1 produces | generates. 6 is a functional block diagram of a drawing control apparatus 300 according to Embodiment 2. FIG. 10 is a flowchart illustrating a drawing control process executed by the drawing control apparatus 300 according to the second embodiment. 10 is a flowchart illustrating processing for calculating relative time in the drawing control apparatus 300 according to the second embodiment. It is a figure which shows the stroke used for description of the process which calculates relative time in the drawing control apparatus 300 of Embodiment 2. FIG. It is a figure which shows an example of the drawing command which the drawing control apparatus 300 of Embodiment 2 produces | generates. FIG. 10 is a diagram illustrating table format data used in the drawing control apparatus according to the third embodiment. FIG. 10 is a diagram illustrating the order of one-way scanning of a laser when the drawing control apparatus according to the fourth embodiment performs drawing. 14 is a flowchart illustrating a drawing control process executed by the drawing control apparatus according to the fourth embodiment.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments to which a drawing control device, a laser irradiation device, a drawing control method, a drawing control program, and a recording medium recording the same are applied will be described below.

  Here, before describing the drawing control apparatus, laser irradiation apparatus, drawing control method, drawing control program, and recording medium on which the drawing control apparatus of the embodiment is used, when drawing is performed with the drawing control apparatus using FIG. The problem of will be described.

  FIG. 2 is a diagram for explaining a problem when drawing is performed by the drawing control apparatus.

  For example, when drawing a wide shape such as a rectangle, by irradiating a laser, a straight line is drawn from the top to the bottom as shown in FIG. Let's draw from left to right.

  In this case, the laser is scanned from left to right, a straight line A is drawn from the point a1 to the point a2, and then it runs idle from the point a2 to the point b1 one line below without irradiating the laser, and again from the point b1. The laser starts scanning rightward, and a straight line B is drawn to the point b2.

  After drawing the straight line A for the section 1, when the straight line B is drawn one line downward, the straight line A is drawn so that the section 1 is heated almost uniformly from end to end, and the remaining heat remains.

  For this reason, when the straight line B is drawn from the point b1 to the point b2 in the area adjacent to one line below the straight line A, the laser output is higher than when the straight line A is drawn in consideration of the residual heat in the section from the point a1 to the point a2. If the drawing is performed with a low value, the amount of heat received by the section between the points b1 and b2 when the straight line B is drawn is the same as the section between the points a1 and a2 when the straight line A is first drawn. The amount of heat received can be made equal, and the straight line B can be drawn without any problem. Note that the scanning speed of the laser when drawing the straight line A and the straight line B is the same, and the scanning speed of the laser is the drawing speed when drawing the drawing target.

  Next, as shown in FIG. 2B, when drawing a bitmap image, if the straight line B is drawn after drawing the straight lines A1, A2, A3, the straight lines A1, A2, A3 are interrupted. Since there is a break, the remaining heat in each of the sections 1 to 5 is not constant.

  In sections 1, 3, and 5, since straight lines A1, A2, and A3 are drawn immediately before the straight line B is drawn, there is residual heat. For this reason, when the straight line B is drawn, it is necessary to reduce the laser output in the sections 1, 3, and 5.

  On the other hand, in sections 2 and 4, a straight line is not drawn immediately before the straight line B is drawn, and there is no residual heat, so there is no need to reduce the laser output.

  As described above, when drawing a bitmap image, accurate drawing cannot be performed unless the residual heat due to the straight lines A1, A2, and A3 drawn before the straight line B to be drawn is taken into consideration. .

  Here, in order to wait for the remaining heat to cool down, it may be possible to provide a standby time. However, if the standby time is provided, there arises a problem that the drawing time becomes long.

  Incidentally, in order to increase the laser scanning speed in order to shorten the drawing time, it is desirable to reciprocate the laser scanning.

  As shown in FIGS. 2 (A) and 2 (B), when scanning is performed only in one way (from left to right), it is necessary to return to the left side through an idle running section for each line. This is because the idle running section can be shortened by performing.

  However, immediately after the straight line A shown in FIG. 2A is drawn, at the points a1 and a2, the point a2 has higher residual heat.

  For this reason, when drawing is performed by reciprocating scanning, the residual heat is large and the temperature is high immediately after the start of the return path, but the temperature decreases with the lapse of time immediately before the end of the return path, so the laser output for drawing the return path should be constant. There is a problem that the medium cannot be heated properly and accurate drawing cannot be performed.

  Furthermore, in the case of a bitmap image, the factor of presence / absence of a line drawn immediately before is added, so it is necessary to adjust the amount of heating by the laser according to the presence / absence of a straight line immediately before.

  FIG. 2C shows an example in which a bitmap image is drawn by reciprocating scanning.

  In section 5, section 3, and section 1 in which straight lines A1, A2, and A3 are drawn immediately before drawing straight line B, the heating amount must be reduced when straight line B is drawn from point b1 to point b2, but straight line A1 Since the elapsed time after subtracting A2, A3 is different in each section, the amount of residual heat is different.

  In section 5, the elapsed time after drawing straight line A3 is shorter than in sections 3 and 1, so the heating amount when drawing straight line B is suppressed, and in section 3, the elapsed time is longer than in section 5, so the heating amount is reduced. Since the elapsed time is longer in the section 2 than in the section 3, the heating amount must be further increased.

  Also, since the elapsed time differs between right and left even within one section, it is desirable to control the heating amount even within the section.

  An object of the present invention is to provide a drawing control apparatus, a laser irradiation apparatus, a drawing control method, a drawing control program, and a recording medium recording the same, which can perform accurate drawing on a medium in a short time.

  Next, in order to perform accurate drawing on the medium in a short time using the drawing control apparatus, laser irradiation apparatus, drawing control method, drawing control program, and recording medium on which the drawing is recorded using FIG. The basic concept of the calculation method of the amount of heat given to the medium will be described.

  FIG. 3 is a diagram for explaining the basic concept of a method for calculating the amount of heat applied to a medium in order to perform accurate drawing on the medium in a short time in the drawing control apparatus and the drawing control method of the present invention.

  As shown in FIG. 3, after the laser is scanned from left to right and a straight line A is drawn between the points a1 and a2, the temperature of the medium at a point b that is a minute region adjacent to one line under the straight line A is shown. Think about how changes occur.

  The rate of change of the temperature T at a certain point b on the medium is proportional to the difference T−Ts between the temperature T at the point b and the temperature Ts around the point b. Here, the temperature Ts is a temperature of the medium at an arbitrary point around the point b, and is a temperature at a point that is not affected by the heating caused by drawing the straight line A.

  Since the temperature T is a function of time, the following differential equation holds.

ここで、tは時間、kは冷却定数と呼ばれる定数であり、実験的に求める。

Here, t is time, and k is a constant called a cooling constant, which is obtained experimentally.

  When equation (1) is solved, equation (2) is obtained.

ここで、Ｔは、直線Ａを引いたことによる媒体の加熱直後からの経過時間ｔにおける点ｂでの媒体の温度、ｋは媒体の性質により定まる冷却定数、Ｔｓは周囲の温度、Ｔ０は加熱直後の点ｂにおける媒体の温度である。

Here, T is the temperature of the medium at the point b at the elapsed time t immediately after heating the medium due to drawing the straight line A, k is the cooling constant determined by the properties of the medium, Ts is the ambient temperature, and T0 is the heating It is the temperature of the medium at the point b immediately after.

  The cooling constant k is experimentally determined to be an optimum value in consideration of drawing an isolated stroke without an adjacent stroke on one line and drawing a stroke with an adjacent stroke on one line. do it.

  Next, consider a case where the point b is irradiated with a laser for drawing. The amount of heat for increasing the temperature from Ts to Te (coloring temperature) is Qs, and the amount of heat for increasing the temperature from T to Te is Q. When the necessary amount of heat is considered to be proportional to the temperature difference, Equation (3) is obtained.

よって、経過時間ｔが経過した際に点ｂで媒体を発色させるために必要な熱量Ｑは式（４）で表すことができる。

Therefore, the amount of heat Q required to cause the medium to develop color at the point b when the elapsed time t has elapsed can be expressed by equation (4).

以下で説明する実施の形態の描画制御装置、レーザ照射装置、描画制御方法、描画制御プログラム、及びこれを記録した記録媒体では、上述の熱量の算出方法を用いる。

In the drawing control apparatus, the laser irradiation apparatus, the drawing control method, the drawing control program, and the recording medium on which the drawing control program according to the embodiments described below is used, the above-described heat amount calculation method is used.

  Next, definitions of terms will be described in describing the drawing control device, the laser irradiation device, the drawing control method, the drawing control program, and the recording medium on which the drawing control program of the embodiment is recorded.

  In the following embodiments, the term “drawing object” is used to indicate a drawing object such as a character, a number, a symbol, and a figure. In addition, the “character” is used as a word representing the whole or a part of a character such as a genre, a sword (making), or a part thereof. Similarly, “numerals”, “symbols”, and “graphics” are used as words that represent all or part of the numbers, symbols, and graphics.

  “Stroke” is used to include one or more line segments (stroke pieces) that are continuously drawn from the position at which drawing is started to the position at which drawing is ended next. For example, when drawing is performed by laser irradiation, a stroke of a character or the like drawn from the irradiation start point of one laser to the end point of irradiation is a stroke. The stroke has coordinates at both ends, and has a thickness (width) corresponding to the laser irradiation range. The stroke may be a part of a curve as well as a part of a straight line.

  The “stroke piece” is a line segment included in the stroke, and is a minimum unit capable of individually setting the laser output or the scanning speed. The stroke piece has the same width as the stroke.

  The stroke piece can be generated, for example, by dividing the stroke into stroke pieces having a predetermined length (ΔX). The length of the stroke piece (ΔX) can be set to an arbitrary length. The stroke piece has a length ΔX and is used for drawing an area having the same width as the stroke. The stroke piece may be used to draw a curved area.

  As described above, drawing objects such as characters, numbers, symbols, and figures include one or more strokes, and the stroke includes one or more stroke pieces.

  It should be noted that the stroke (one stroke) of the embodiment may be the same as or different from the stroke determined by a public organization (for example, Japanese Standards Association, ISO, etc.).

  In addition, the term “drawing order” includes the order of drawing stroke pieces included in the drawing target (including the drawing order of which stroke piece is drawn from which end), and a plurality of drawing targets included in the text etc. These are used to have two meanings of the order of drawing.

  The drawing control apparatus, laser irradiation apparatus, drawing control method, drawing control program, and recording medium recording the same according to the first to fifth embodiments will be described below.

<Embodiment 1>
FIG. 4 is a diagram illustrating an example of a hardware configuration of a laser marking apparatus including the drawing control apparatus according to the first embodiment.

  The laser marking device 100 includes a drawing device 10 that irradiates a laser, and a drawing control device 20 that controls drawing of the drawing device 10. The drawing apparatus 10 includes a laser oscillator 11 that irradiates a laser, a direction control mirror 13 that changes the laser irradiation direction, a direction control motor 12 that drives the direction control mirror 13, an optical lens 14, and a condenser lens 15.

  The laser oscillator 11 is a semiconductor laser (LD (Laser Diode)), but may be a gas laser, a solid laser, a liquid laser, or the like. The direction control motor 12 is, for example, a servo motor that controls the direction of the reflecting surface of the direction control mirror 13 to two axes. The direction control motor 12 and the direction control mirror 13 constitute a galvano mirror. The optical lens 14 is a lens that increases the spot diameter of the laser light, and the condenser lens 15 is a lens that converges the laser light.

  The thermal rewritable medium 50 is a rewritable heat-sensitive medium that develops color when heated to a temperature of 180 ° C. or higher and rapidly cools and decolors when heated to a temperature of 130 to 170 ° C. Normal thermal paper and thermal rewritable media do not absorb near-infrared laser light, so when using a laser light source that oscillates near-infrared laser wavelengths (semiconductor lasers, solid-state laser YAG, etc.) It is necessary to add a material or a layer that absorbs laser light to the rewritable medium. Note that rewriting means recording by heating with laser light, and erasing by heating with laser light, hot air, hot stamp, or the like. The non-rewritable thermal paper refers to thermal paper that is difficult to be decolored by heating. In this embodiment, the case where the thermal rewritable medium 50 is used will be described as an example of the medium to be used. However, it is also suitable for a medium that cannot be rewritten such as thermal paper, plastic, metal, etc. that cannot be rewritten. Applicable to.

  FIG. 5 is a diagram illustrating an example of a hardware configuration of the drawing control apparatus 20 according to the first embodiment. FIG. 5 is a hardware configuration diagram when the drawing control apparatus 20 is mainly implemented by software, and a computer is used as an entity. When the drawing control apparatus 20 is realized without using a computer as an entity, an IC generated for a specific function such as an ASIC (Application Specific Integrated Circuit) is used.

  The drawing control device 20 includes a CPU 31, a memory 32, a hard disk 35, an input device 36, a CD-ROM drive 33, a display 37, and a network device 34.

  The hard disk 35 stores a font data DB 41 that stores font data of a series of characters of a stroke font, a character drawing program 42 that generates a drawing command that eliminates duplication from the font data, and controls the drawing device 10, and a drawing command DB. Has been. The hard disk 35 also stores other data necessary for drawing to be drawn.

  The CPU 31 reads and executes the character drawing program 42 from the hard disk 35, and draws characters on the thermal rewritable medium 50 by the procedure described later. The memory 32 is a volatile memory such as a DRAM, and serves as a work area when the CPU 31 executes the character drawing program 42.

  The input device 36 is a device for a user to input an instruction to control the drawing device 10 such as a mouse or a keyboard, and may further include a device that reads a drawing target such as a scanner.

  A drawing condition representing a text or a figure (hereinafter referred to as a text) to be drawn on the thermal rewritable medium 50, a size of a drawing target included in the text, or the like is input by the user via the input device 36, for example, a hard disk, for example. 35. The drawing conditions include data representing the position and size of each drawing target in the text.

  The display 37 is a user interface that displays a GUI (Graphical User Interface) screen with a predetermined resolution and number of colors based on, for example, screen information instructed by the character drawing program 42. For example, an input field for characters to be drawn on the thermal rewritable medium 50 is displayed.

  The CD-ROM drive 33 is configured to be detachable from the CD-ROM 38, and is used when reading data from the CD-ROM 38 and writing data on a recordable recording medium. The font data DB 41 and the character drawing program 42 are distributed in a state stored in the CD-ROM 38, read from the CD-ROM 38, and installed in the hard disk 35. In addition, the CD-ROM 38 can be replaced with a nonvolatile memory such as a DVD, a Blu-ray disc, an SD card, a memory stick (registered trademark), a multimedia card, and an xD card.

  The network device 34 is an interface (for example, an Ethernet (registered trademark) card) for connecting to a network such as a LAN or the Internet, and executes processing in accordance with protocols defined in the physical layer and data link layer of the OSI basic reference model. Thus, a drawing command corresponding to the character code can be transmitted to the drawing apparatus 10. The font data DB 41 and the character drawing program 42 can be downloaded from a predetermined server connected via a network. Note that the drawing control apparatus 20 and the drawing apparatus 10 may be directly connected via USB (Universal Serial Bus), IEEE 1394, wireless USB, Bluetooth, or the like, not via a network.

  A drawing target to be drawn on the thermal rewritable medium 50 is input from the input device 36 and stored in the hard disk 35.

  When the drawing target is a character, the drawing target is specified by a character code such as UNICODE or JIS code, and the drawing control device 20 reads out the font data of the character corresponding to the character code from the font data DB 41, and the drawing device 10 is read out. Used when generating drawing commands for control.

  When the drawing target is a figure, the drawing target is specified by, for example, bitmap image data representing a bitmap image.

  Next, the drawing control apparatus 20 according to the first embodiment will be described with reference to FIG. Here, a case where the drawing target is a graphic represented by bitmap image data will be described.

  FIG. 6 is a functional block diagram of the drawing control apparatus 20 according to the first embodiment.

  The drawing control apparatus 20 according to the first embodiment includes a main control unit 201, a stroke information generation unit 202, a stroke piece generation unit 203, a drawing order determination unit 204, a speed setting unit 205, an idle running section setting unit 206, and a standby time setting unit. 207, an adjacent stroke determination unit 208, an elapsed time calculation unit 209, a laser output setting unit 210, a drawing command generation unit 211, and a data storage unit 212.

  The main control unit 201 is a control unit that supervises the processing of the drawing control apparatus 20 of the first embodiment.

  The stroke information generation unit 202 generates stroke information from bitmap image data representing a drawing target. The stroke information is data representing the coordinates of both ends of the stroke. For example, the stroke information generation unit 202 generates stroke information in the X-axis direction from the bitmap data in the XY coordinates (X-axis is horizontal and right is positive, Y-axis is vertical and downward is positive).

  The stroke piece generation unit 203 generates a stroke piece of length ΔX by dividing the stroke represented by the stroke information generated by the stroke information generation unit 202 into predetermined lengths (ΔX). The drawing control apparatus 20 according to the first embodiment generates a drawing command by dividing the drawing target for each stroke piece.

  Here, dividing the drawing object into stroke pieces means dividing the drawing object into rectangular regions determined by the size of the stroke piece, that is, dividing the drawing object into a mesh shape.

  The drawing order determination unit 204 determines the order in which the strokes represented by the stroke information generated by the stroke information generation unit 202 are drawn. For example, the drawing order is determined according to the positions of both ends of each stroke so that the drawing can be performed most efficiently when the entire drawing target is drawn.

  The speed setting unit 205 sets a laser scanning speed when drawing each stroke piece. The speed setting unit 205 increases the laser scanning speed as the elapsed time is shorter.

  The free running section setting unit 206 sets a free running section for moving the laser irradiation point without drawing when moving from the end point of the stroke to the start point of the next stroke. For example, as in the drawing order, the idle running section is determined according to the positions of both ends of each stroke so that the drawing can be performed most efficiently when the entire drawing target is drawn.

  The waiting time setting unit 207 sets a waiting time for waiting for the galvanometer mirror to stabilize at the start point and the end point of the idling section.

  The adjacent stroke determination unit 208 determines whether there is an adjacent stroke piece on one line when drawing a stroke piece. In the first embodiment, in order to perform reciprocal scanning, a stroke piece adjacent on one line is a stroke piece having an end point whose X coordinate is the same as that of the start point of the stroke piece to be generated. A stroke piece generated on one line of the stroke piece to be generated.

  When drawing is performed by one-way scanning, a stroke piece adjacent on one line is a stroke piece having a start point (or end point) having the same X coordinate as the start point (or end point) of the stroke piece to be generated by the drawing command. In this case, the stroke piece may be generated on one line of the stroke piece that is the generation target of the drawing command.

  When the stroke piece is drawn, the elapsed time calculation unit 209 calculates the elapsed time from the end of drawing the stroke piece adjacent on one line.

  The laser output setting unit 210 sets the output of the laser when drawing a stroke piece based on the determination result of the adjacent stroke determination unit 208 and the elapsed time calculated by the elapsed time calculation unit 209. The output determination unit 210 decreases the laser output as the elapsed time is shorter.

  The drawing command generation unit 211 is set by the drawing order determined by the drawing order determination unit 204, the laser scanning speed set by the speed setting unit 205, the free running section set by the free running section setting unit 206, and the standby time setting unit 207. The drawing command is generated based on the waiting time for the drawing and the laser output when drawing the stroke piece determined by the laser output setting unit 210. The drawing command generation unit 211 stores the generated drawing command in the drawing command DB.

  The data storage unit 212 includes stroke information generated by the stroke information generation unit 202, stroke piece information indicating the coordinates of both ends of the stroke piece generated by the stroke piece generation unit 203, a drawing order determined by the drawing order determination unit 204, and speed setting. Laser scanning speed set by the unit 205, idle running interval set by the idle running interval setting unit 206, standby time set by the standby time setting unit 207, and laser when drawing a stroke piece determined by the laser output setting unit 210 The drawing command generated by the drawing command generation unit 211 is stored.

  The data storage unit 212 is realized by the memory 32 or the hard disk shown in FIG.

  Next, a method in which the stroke information generation unit 202 of the drawing control apparatus 20 according to the first embodiment generates stroke information from bitmap image data representing a drawing target will be described with reference to FIG.

  FIG. 7 is a diagram illustrating a method in which the stroke information generation unit 202 of the drawing control apparatus 20 according to the first embodiment generates stroke information from bitmap image data representing a drawing target.

  The stroke information generation unit 202 converts the bitmap image data shown in FIG. 7 from (1) to (5) while reciprocating left and right (reciprocating scanning) at a predetermined pitch from top to bottom. Is scanned in the direction of the arrow, and a stroke is generated for a section having a drawing target. It should be noted that no scanning is performed for the section having no drawing target.

  In FIG. 7, the stroke information generation unit 202 generates strokes 1 to 8 in order from the top to the bottom.

  As described above, the stroke information generation unit 202 generates stroke information representing the strokes 1 to 8.

  FIG. 7 shows a method for generating a stroke for a part of bitmap image data for convenience of explanation, but the stroke information generation unit 202 generates a stroke for the entire bitmap image data.

  The stroke piece generation unit 203 further divides the strokes 1 to 8 shown in FIG. 7 into stroke pieces having a predetermined length (ΔX). The stroke pieces will be described later.

  Next, laser output when the drawing control apparatus 20 according to the first embodiment draws a drawing target will be described.

  In the first embodiment, when drawing each stroke piece, if there is a stroke piece already drawn on one line, the laser output is adjusted according to the elapsed time from the drawing time of the stroke piece on one line. Thus, accurate drawing is performed. The laser scanning speed is kept constant regardless of whether or not there is a stroke piece already drawn on one line.

  Here, assuming that the amount of heat Q required to develop the color of the thermal rewritable medium 50 expressed by the equation (4) is proportional to the laser output, the laser output P required to draw a stroke piece is: And can be represented by the formula (5).

ただし、Ｐｓは、ある一定の走査速度Ｖｓにおいて、周囲に他のストローク片が存在しない単独のストローク片をサーマルリライタブル媒体５０に描画する際に必要なレーザの出力である。ここで、走査速度Ｖｓは走査速度のデフォルト値であり、レーザ出力Ｐｓはレーザ出力のデフォルト値である。

However, Ps is a laser output necessary for drawing a single stroke piece on the thermal rewritable medium 50 with no other stroke piece in the vicinity at a certain scanning speed Vs. Here, the scanning speed Vs is a default value of the scanning speed, and the laser output Ps is a default value of the laser output.

  K is a cooling constant of the thermal rewritable medium 50. t is an elapsed time from the time when drawing of a stroke piece on one line ends.

  The drawing control apparatus 20 according to the first embodiment performs drawing of a drawing target using the laser output represented by the formula (5).

  Next, a drawing control process performed by the drawing control apparatus 20 according to the first embodiment will be described with reference to FIGS.

  FIG. 8 is a flowchart illustrating a drawing control process executed by the drawing control apparatus 20 according to the first embodiment. The flowchart shown in FIG. 8 represents the drawing control method of the first embodiment. This drawing control method is realized by executing the drawing control program of the first embodiment.

  FIG. 9 is a diagram illustrating a part of a graphic drawn by the drawing control process executed by the drawing control apparatus 20 according to the first embodiment. In the first embodiment, when drawing a drawing target on the thermal rewritable medium 50, reciprocal scanning is performed.

  The drawing control device 20 generates stroke information (step S1). The process of step S <b> 1 is a process executed by the stroke information generation unit 202 of the drawing control apparatus 20.

  The stroke information generation unit 202 stores the strokes in the data storage unit 212 in the order in which the strokes are scanned. For example, when strokes 1 to 8 are generated as illustrated in FIG. 7, the stroke information generation unit 202 stores the strokes 1 to 8 in the order in the data storage unit 212.

  Next, the drawing control apparatus 20 sets the drawing speed to the standard speed (Vs) (step S2). The process of step S <b> 2 is a process executed by the speed setting unit 205 of the drawing control apparatus 20.

  Next, the drawing control apparatus 20 reads one stroke information stored in the data storage unit 212 from the younger one (step S3). For example, in FIG. 9, the first stroke is the top stroke (the stroke starting from the point (7)). Note that the process of step S3 is executed by the main control unit 201 of the drawing control apparatus 20.

  Next, the drawing control apparatus 20 sets an idle running section (step S4). The process of step S4 is a process executed by the idling section setting unit 206 of the drawing control apparatus 20. This idle running section is a section in which the focus of the galvanometer mirror is moved without irradiating the laser, and is included in the drawing command. That is, the process of step S4 is a process for moving the focus of the galvanometer mirror to the start point of the stroke to be drawn. For example, in FIG. 9, the focal point of the galvanometer mirror is moved to point (7).

  The standby time setting unit 207 sets the standby time before and after the idle running section. The waiting time is a predetermined time based on the characteristics of the galvanometer mirror, the scanning speed, and the idling speed, and both when switching from drawing to idling and when switching from idling to drawing. (That is, before and after the idle running section).

  Next, the drawing control apparatus 20 determines whether there is an adjacent stroke piece on one line (step S5). The process in step S5 is a process executed by the adjacent stroke determination unit 208 of the drawing control apparatus 20.

  Since the point (7) shown in FIG. 9 is the start point of the stroke drawn first, there is no stroke piece on one line, and step S5 is determined as NO.

  In step S5, determination is performed for each stroke piece, not for each stroke.

  If the drawing control device 20 determines in step S5 that there is no stroke on one line (S5: NO), it sets the laser output to the standard output Ps (step S6).

  The drawing control device 20 stores the drawing command of the stroke piece for which the laser output is set in step S6 in the drawing command DB (step S9). The process of step S9 is a process executed by the drawing command generation unit 211 of the drawing control apparatus 20.

  The drawing command includes the laser scanning speed set in step S2, the laser output set in step S6, and the coordinates of both ends of the stroke piece.

  The drawing control apparatus 20 determines whether or not the end point of the stroke piece currently being processed is the end point of the stroke including the stroke piece (step S10). The process of step S10 is a process executed by the main control unit 201 of the drawing control apparatus 20.

  Whether or not the end point of the stroke piece currently being processed is the end point of the stroke including the stroke piece may be determined, for example, by comparing the coordinates of the end point of the stroke piece with the coordinates of the end point of the stroke.

  If the drawing control device 20 determines that it is not the end point of the stroke (S10: NO), the flow proceeds to step S11.

  The drawing control device 20 selects the next stroke piece (step S11). The process of step S11 is a process executed by the main control unit 201 of the drawing control apparatus 20.

  The next stroke piece is represented by a value obtained by increasing the coordinates of the start point and the end point by ΔX.

  When the process of step S11 ends, the drawing control apparatus 20 returns the flow to step S5. Thereby, the drawing control apparatus 20 repeatedly executes the processes of steps S5 to S10 until the end point of the stroke is reached.

  If the drawing control device 20 determines in step S10 that it is the end point of the stroke (S10: YES), it determines whether drawing commands have been generated for all strokes (step S12).

  For example, in FIG. 9, when the process is executed for each stroke piece from the point (7) to reach the point (11), the processing for all the strokes has not been completed. It is determined that a drawing command has not been generated for the stroke (S12: NO), and the flow returns to step S3.

  Here, it is assumed that when returning to step S3, the drawing control apparatus 20 reads a stroke starting from the point (1) shown in FIG.

  In step S4, the free-running section setting unit 206 of the drawing control apparatus 20 sets a free-running section for free-running from point (3) to point (1) shown in FIG.

  Next, in step S5, in FIG. 9, since there is a stroke on one line of point (1) (S5: YES), the flow proceeds to step S7.

  The drawing control device 20 calculates an elapsed time from the end of drawing of the stroke piece adjacent on one line to the start of drawing of the stroke piece for which a drawing command is currently being created (step S7). Step S <b> 7 is a process executed by the elapsed time calculation unit 209 of the drawing control apparatus 20.

  Here, assuming that the elapsed time is Δt, the elapsed time is <1> a stroke for drawing from the end of drawing the stroke piece on one line to the drawing of the stroke piece for which the current drawing command is being created. It is represented by the sum of the time Δt1 for drawing a piece, <2> idle time Δt2, and <3> standby time Δt3 (Δt1 + Δt2 + Δt3).

  In FIG. 9, the time Δt1 required for drawing the stroke piece from the drawing of the stroke piece on one line to the drawing of the stroke piece for which the drawing command is being created is a point (12) in FIG. After drawing the stroke piece between the point (2) and the drawing of the stroke piece starting from the point (1) and before drawing the stroke piece, the time for drawing the stroke piece. For this reason, in FIG. 9, it is the time required for drawing the stroke piece between the point (2) and the point (3). Therefore, Δt1 = ΔX / Vs.

  The idle running time Δt2 is the time required for the idle running section from the end of drawing the stroke piece on one line to the drawing of the stroke piece for which the current drawing command is being created. Can be obtained on the basis of the coordinates of the start point and end point of and the idling speed Vj.

  If the coordinates of the start point of the idle running section are (x1, y1) and the coordinate path (x2, y2) of the end point, it can be expressed by equation (6).

図９では、点（３）から点（２）に空走する空走区間の所要時間として求まる。

In FIG. 9, it is obtained as the required time of the idle running section running idle from point (3) to point (2).

  The waiting time Δt3 is a time set before and after the idle running section, and is a predetermined time determined in advance based on the characteristics of the galvanometer mirror, the scanning speed, and the idle running speed. Here, Δt3 = twj + twd, where waiting time twj when switching from drawing to idle running and standby time twd when switching from idle running to drawing are set.

  In step S7, the elapsed time calculation unit 209 obtains Δt, which is the total time of Δt1, Δt2, and Δt3.

  Next, the drawing control device 20 sets the output of the laser (step S8). The process of step S8 is a process executed by the laser output setting unit 210 of the drawing control apparatus 20.

  The laser output setting unit 210 calculates the laser output based on the equation (5) using the elapsed time Δt calculated by the elapsed time calculation unit 209 in step S7.

  When the process of step S8 is completed, in step S9, the stroke piece drawing command for which the laser output is set in step S8 is stored in the drawing command DB.

  The drawing command includes the laser scanning speed set in step S2, the laser output set in step S8, and the coordinates of both ends of the stroke piece.

  In FIG. 9, a drawing command for a stroke piece between points (1) and (6) is stored in the drawing command DB.

  If the drawing control device 20 determines that the drawing command has been generated for all strokes in step S12 by repeatedly executing the above processing (S12: YES), the drawing control device 20 advances the flow to step S13.

  The drawing control device 20 integrates drawing commands (step S13). The process in step S13 is a process executed by the drawing command generation unit 211 of the drawing control apparatus 20.

  The rendering command integration process is not an essential process, but is a process performed to compress the data amount.

  For example, the main control unit 210 integrates drawing commands of stroke pieces that are continuous with each other among stroke pieces included in the same stroke and that have the same laser output.

  Now, the rendering command integration process will be described with reference to FIG.

  FIG. 10 is a diagram for explaining the rendering command integration processing.

  The arrows shown in FIG. 10A indicate each stroke piece. By the processes in steps S1 to S12 described above, a drawing command for the stroke piece indicated by each arrow is generated.

  Here, when drawing commands for stroke pieces included in the same stroke and having the same laser output are integrated, arrows A1 to A5 shown in FIG. As shown by an arrow B1 in FIG. 10B, drawing is performed with one drawing command.

  The drawing control device 20 outputs a drawing command (step S14). The process in step S14 is a process executed by the drawing command generation unit 211 of the drawing control apparatus 20. The drawing command generation unit 211 inputs a drawing command to the drawing device 10. Thereby, in the drawing apparatus 10, accurate drawing is performed by adjusting the output of the laser in accordance with the elapsed time from the drawing time on one line.

  As described above, according to the drawing control apparatus 20 of the first embodiment, it is possible to set the laser output according to the elapsed time from the drawing end time of the stroke piece on one line. As a result, even when the thermal rewritable medium 50 has residual heat due to the drawing of stroke pieces on one line, it is possible to perform drawing accurately by adjusting the output of the laser.

  In addition, since the drawing control apparatus 20 of the first embodiment adjusts the output of the laser as described above, accurate drawing can be performed even when reciprocating scanning is performed, and the drawing time can be shortened. Can do.

  FIG. 11 is a diagram illustrating an example of a drawing command generated by the drawing control apparatus 20 according to the first embodiment.

  The five strokes shown in FIG. 11A are the same strokes as the five strokes shown in FIG.

  As shown in FIG. 11A, the origin O is set at the upper left of the drawing area, and the horizontal axis is the X axis (right direction is positive) and the vertical direction is the Y axis (down direction is positive).

  The point (7) shown in FIG. 11A is (X, Y) = (10, 10), the point (10) is (X, Y) = (40, 10), and the point (11) is (X, Y). ) = (60,10), point (12) is (X, Y) = (70,10), point (2) is (X, Y) = (80,10), and point (1) is (X, Y) Y) = (90,10), point (1) is (X, Y) = (80,20), point (6) is (X, Y) = (70,20), point (13) is (X , Y) = (60, 20), point (9) is (X, Y) = (50, 20), point (8) is (X, Y) = (40, 20), point (4) is ( X, Y) = (30, 20), point (5) is (X, Y) = (20, 20), and point (14) is (X, Y) = (0, 20).

  Also, here, in the drawing command, the stroke thickness is t, the movement to the designated coordinates (empty running) without laser irradiation is m, the straight line drawing to the designated coordinates is d, and the waiting time is w (msec (milliseconds). )), P is the laser output (ratio to the default value of laser output (percentage (%))), and s is the scanning speed (ratio to the default value of scanning speed (percentage (%))).

  A drawing command for drawing the five strokes shown in FIG. 11A from the point (7) closest to the origin O in the uppermost row is as shown in FIG. 11B.

  In the drawing command shown in FIG. 11B, first, the scanning speed s is set to 100 (%), the stroke thickness t is set to 10 (points), and (X, Y) = (10 , 10) Run to the point (7) (m).

  Next, the laser output (p) is set to 100%, and straight line drawing is performed until (X, Y) = (60, 10) (d).

  Next, it runs idle to (X, Y) = (70, 10) (m), and draws a straight line to (X, Y) = (90, 10) (d). Thereby, up to the point (3) is drawn.

  Next, the standby time w is set to 50 (msec) at the point (3), and the vehicle runs idly to the point (1) where (X, Y) = (80, 20) (m).

  Since there is a stroke drawn on one line at the point (1), the laser output p is set to 20% of the default value Ps, and a straight line is drawn up to the point (6) of (X, Y) = (70, 20). Perform (d).

  At point (6), since there is no stroke on one line, the laser output p is returned to 100%, and a straight line is drawn up to point (13) of (X, Y) = (60, 20) (d).

  Since there is a stroke on one line from the point (13), the laser output p is reduced to 50 (%), and a straight line is drawn up to the point (9) of (X, Y) = (50, 20) (d). .

  At point (9), since there is still a stroke on one line, the laser output p is set to 60 (%), and a straight line is drawn up to point (8) of (X, Y) = (40, 20) (d ).

  At point (8), since there is still a stroke on one line, the laser output is set to 70 (%), and a straight line is drawn up to point (4) of (X, Y) = (30, 20) (d). .

  Next, the vehicle runs to the point (5) of (X, Y) = (20, 20) (m).

  Since there is a stroke on one line from the point (5), the laser output is set to 78 (%), and a straight line is drawn up to the point (14) of (X, Y) = (10, 20) (d). .

  Since there is no stroke on one line from the point (14), the laser output is set to 100 (%) and a straight line is drawn up to the point (15) of (X, Y) = (0, 20) (d). .

  As described above, four strokes can be drawn from the point (7) to the point (15) while adjusting the laser output in accordance with the elapsed time after the drawing of the stroke on one line is completed.

  A stroke located one line below the point (14) to the point (4) can be similarly drawn.

  In the above description, the case where the drawing target is a graphic represented by bitmap image data has been described. However, the drawing target may be a character. In particular, when a character is drawn thickly, if the drawing control device 20 according to the first embodiment performs drawing, the character can be drawn accurately in a short time.

<Embodiment 2>
Next, the drawing control apparatus 300 according to the second embodiment will be described with reference to FIG. Here, a case where the drawing target is a graphic represented by bitmap image data will be described.

  FIG. 12 is a functional block diagram of the drawing control apparatus 300 according to the second embodiment.

  The drawing control apparatus 300 according to the second embodiment includes a main control unit 301, a stroke information generation unit 302, a stroke piece generation unit 303, a drawing order determination unit 304, a speed setting unit 305, an idle running section setting unit 306, and a standby time setting unit. 307, an adjacent stroke determination unit 308, an elapsed time calculation unit 309, a laser output setting unit 310, a drawing command generation unit 311, and a data storage unit 312.

  Main control unit 301, stroke information generation unit 302, stroke piece generation unit 303, drawing order determination unit 304, idle run section setting unit 306, standby time setting unit 307, adjacent stroke determination unit 308, elapsed time calculation unit 309, drawing command The generation unit 311 and the data storage unit 312 are the main control unit 201, stroke information generation unit 202, stroke piece generation unit 203, drawing order determination unit 204, idle running section setting unit 206, standby time setting unit of the first embodiment. 207, adjacent stroke determination unit 208, elapsed time calculation unit 209, drawing command generation unit 211, and data storage unit 212 are the same.

  The speed setting unit 305 of the second embodiment sets the laser scanning speed (drawing speed) according to the elapsed time from the drawing end time of the stroke on one line, and the laser output setting unit 310 sets the laser output to the default value. The point set to Ps (a constant value) is different from the speed setting unit 205 and the laser output setting unit 210 of the first embodiment.

  Hereinafter, the difference from the first embodiment will be mainly described.

  Consider the adjustment of the amount of heat applied to the medium in which the residual heat remains by adjusting the laser scanning speed while keeping the laser output constant at the default value Ps.

  Since the amount of heat given to the medium is considered to be inversely proportional to the scanning speed, the speed v when the amount of heat is changed by the speed can be expressed by Expression (7).

ここで、Ｖｓは実施の形態１で説明したデフォルト値の速度である。また、ｋは媒体の冷却定数である。ｔは、処理中のストロークの一行上に存在するストローク片の描画が終了する時刻からの経過時間である。

Here, Vs is the default speed described in the first embodiment. K is a cooling constant of the medium. t is the elapsed time from the time when drawing of a stroke fragment existing on one line of the stroke being processed ends.

  In the second embodiment, when each stroke piece is drawn using the scanning speed represented by Expression (7), if there is a stroke piece already drawn on one line, the stroke piece on one line is drawn. Accurate drawing is performed by adjusting the scanning speed of the laser in accordance with the elapsed time from the time. Note that the laser output is constant at the default value Ps regardless of whether or not there is a stroke piece already drawn on one line.

  The drawing control apparatus 300 according to the second embodiment draws a drawing target using the laser scanning speed represented by the equation (7).

  Next, a drawing control process performed by the drawing control apparatus 300 according to the second embodiment will be described with reference to FIG. In addition, FIG. 9 of Embodiment 1 is used for description of the flowchart of FIG.

  FIG. 13 is a flowchart illustrating a drawing control process executed by the drawing control apparatus 300 according to the second embodiment. The flowchart shown in FIG. 13 represents the drawing control method of the second embodiment. This drawing control method is realized by executing the drawing control program of the second embodiment.

  The drawing control apparatus 300 generates stroke information (step S201). The process in step S201 is a process executed by the stroke information generation unit 302 of the drawing control apparatus 300.

  The stroke information generation unit 302 stores the strokes in the data storage unit 312 in the order in which the strokes are scanned.

  Next, the drawing control apparatus 300 sets the laser output to the standard output (Ps) (step S202). The process of step S202 is a process executed by the laser output setting unit 310 of the drawing control apparatus 300.

  Next, the drawing control apparatus 300 reads one stroke information stored in the data storage unit 312 from the younger one (step S203). For example, in FIG. 9, the first stroke is the top stroke (the stroke starting from the point (7)). Note that the process of step S203 is a process executed by the main control unit 301 of the drawing control apparatus 300.

  Next, the drawing control apparatus 300 sets an idle running section (step S204). The process of step S204 is a process executed by the idle section setting unit 306 of the drawing control apparatus 300. This idle running section is a section in which the focus of the galvanometer mirror is moved without irradiating the laser, and is included in the drawing command. That is, the process of step S204 is a process for moving the focus of the galvanometer mirror to the start point of the stroke to be drawn. For example, in FIG. 9, the focal point of the galvanometer mirror is moved to point (7).

  The standby time setting unit 307 sets the standby time before and after the idle running section. The waiting time is a predetermined time based on the characteristics of the galvanometer mirror, the scanning speed, and the idling speed, and both when switching from drawing to idling and when switching from idling to drawing. (That is, before and after the idle running section).

  Next, the drawing control apparatus 300 calculates a relative time (step S205). The relative time is calculated by drawing the stroke piece on one line when drawing the stroke piece, and the elapsed time from drawing the stroke piece on one line to drawing the stroke piece to be processed. This is done to calculate For this reason, the process of step S205 is a process which the elapsed time calculation part 309 of the drawing control apparatus 300 performs.

  In the second embodiment, the amount of heat received by the thermal rewritable medium 50 is adjusted by adjusting the scanning speed of the laser. Accordingly, the laser scanning speed may vary depending on the stroke piece.

  For this reason, the calculation of the elapsed time in the second embodiment is different from that in the first embodiment. In the second embodiment, for example, the time at which drawing is started from the point (7) shown in FIG. 9 is set as the reference time (t = 0), and the relative time (elapsed time) with respect to the time at each point is calculated.

  A method for calculating the elapsed time in the second embodiment will be described later with reference to FIGS.

  Next, the drawing control apparatus 300 determines whether there is an adjacent stroke piece on one line (step S206). The process of step S206 is a process executed by the adjacent stroke determination unit 308 of the drawing control apparatus 300.

  Since the point (7) shown in FIG. 9 is the start point of the stroke drawn first, there is no stroke piece on one line, and step S206 is determined as NO.

  In step S206, the determination is made not for each stroke but for each stroke piece.

  If the drawing control apparatus 300 determines in step S206 that there is no stroke on one line (S206: NO), it sets the laser scanning speed to the standard speed Vs (step S207).

  The drawing control apparatus 300 stores the drawing command for the stroke piece for which the laser scanning speed has been set in step S207 in the drawing command DB (step S209). The process in step S209 is a process executed by the drawing command generation unit 311 of the drawing control apparatus 300.

  The drawing command includes the laser output set in step S202, the laser scanning speed set in step S207, and the coordinates of both ends of the stroke piece.

  The drawing control apparatus 300 determines whether or not the end point of the stroke piece is the end point of the stroke including the stroke piece (step S210). The process of step S210 is a process executed by the main control unit 301 of the drawing control apparatus 300.

  Whether or not the end point of the stroke piece is the end point of the stroke including the stroke piece may be determined, for example, by comparing the coordinates of the end point of the stroke piece with the coordinates of the end point of the stroke.

  If the drawing control apparatus 300 determines that it is not the end point of the stroke (S210: NO), the flow proceeds to step S211.

  The drawing control apparatus 300 selects the next stroke piece (step S211). The process in step S211 is a process executed by the main control unit 301 of the drawing control apparatus 300.

  The next stroke piece is represented by a value obtained by increasing the coordinates of the start point and the end point by ΔX.

  When the process of step S211 ends, the drawing control apparatus 300 returns the flow to step S205. Thereby, the drawing control apparatus 300 repeatedly executes the processes of steps S205 to S210 until the end point of the stroke is reached.

  If the drawing control apparatus 300 determines in step S210 that it is the end point of the stroke (S210: YES), it determines whether drawing commands have been generated for all strokes (step S212).

  For example, in FIG. 9, when the process is executed for each stroke piece from the point (7) to reach the point (11), the processing for all the strokes has not been completed. It is determined that a drawing command has not been generated for the stroke (S212: NO), and the flow returns to step S203.

  Here, it is assumed that when returning to step S203, the drawing control apparatus 300 reads a stroke starting from the point (1) shown in FIG.

  In step S204, the free-running section setting unit 306 of the drawing control apparatus 300 sets a free-running section for free-running from point (3) to point (1) shown in FIG.

  Next, in step S206, in FIG. 9, since there is a stroke on one line of point (1) (S206: YES), the flow proceeds to step S208.

  Next, the drawing control apparatus 300 sets the laser scanning speed using the elapsed time Δt (step S208). The process in step S208 is a process executed by the speed setting unit 305 of the drawing control apparatus 300.

  The speed setting unit 305 calculates the laser scanning speed based on Expression (7) using the elapsed time Δt calculated by the elapsed time calculation unit 309 in step S205.

  When the process of step S208 ends, in step S209, the stroke piece drawing command for which the laser scanning speed has been set in step S208 is stored in the drawing command DB.

  The drawing command includes the laser output set in step S202, the laser scanning speed set in step S208, and the coordinates of both ends of the stroke piece.

  In FIG. 9, a drawing command for a stroke piece between points (1) and (6) is stored in the drawing command DB.

  If the drawing control apparatus 300 determines in step S212 that the drawing command has been generated for all strokes by repeatedly executing the above processing (S212: YES), the drawing control apparatus 300 advances the flow to step S213.

  The drawing control apparatus 300 integrates drawing commands (step S213). The process in step S213 is a process executed by the drawing command generation unit 311 of the drawing control apparatus 300.

  The rendering command integration process is not an essential process, but is a process performed to compress the data amount.

  For example, the main control unit 210 integrates drawing commands of stroke pieces that are continuous with each other among stroke pieces included in the same stroke and that have the same laser output.

  The drawing control apparatus 300 outputs a drawing command (step S214). The process of step S214 is a process executed by the drawing command generation unit 311 of the drawing control apparatus 300. The drawing command generation unit 211 inputs a drawing command to the drawing device 10. Thereby, in the drawing apparatus 10, accurate drawing is performed by adjusting the output of the laser in accordance with the elapsed time from the drawing time on one line.

  As described above, according to the drawing control apparatus 300 of the second embodiment, the laser output can be set according to the elapsed time from the drawing end time of the stroke piece on one line. As a result, even when there is residual heat in the medium due to the drawing of stroke pieces on one line, it is possible to perform drawing accurately by adjusting the output of the laser.

  In addition, since the drawing control apparatus 300 according to the second embodiment adjusts the output of the laser as described above, accurate drawing can be performed even when reciprocating scanning is performed, and the drawing time can be shortened. Can do.

  Here, when the drawing start time of the point (1) shown in FIG. 9 is t1, and the drawing completion time of the point (2) is t2, the equation (7) is expressed as the equation (8). The scanning speed of the laser when drawing is started from the point (1) can be obtained by the equation (8).

すなわち、ｔ１−ｔ２は、点（２）での描画が終了してから、点（１）での描画を開始するまでの経過時間Δｔ（＝ｔ１−ｔ２）である。

That is, t1-t2 is an elapsed time Δt (= t1-t2) from the end of drawing at the point (2) to the start of drawing at the point (1).

  As with the elapsed time Δt of the first embodiment, the elapsed time Δt is drawn between the end of <1> drawing a stroke piece on one line and the drawing of the stroke piece for which the current drawing command is being created. It is represented by the sum (Δt1 + Δt2 + Δt3) of time Δt1 required for drawing stroke pieces, <2> idle running time Δt2, and <3> standby time Δt3.

  For example, when drawing is started from the point (8), the point (10) having the same X coordinate value exists on one line of the point (8).

  Here, the drawing start time at the point (8) is t8, the drawing end time at the point (10) is t10, the waiting time twj at the point (11), the waiting time twd at the point (12), the point (3 ) At standby time twj at point (1) and standby time twd at point (1).

  Further, the scanning speed from the point (10) to the point (11) is Vs (default value), the idle running speed from the point (11) to the point (12) is Vj, and the scanning speed from the point (12) to the point (3). Vs (default value), the scanning speed from point (1) to point (6) is V1, the scanning speed from point (6) to point (13) is Vs (default value), and point (13) to point (8 ) To V2.

  Further, the distance between the point (10) and the point (11) is 2ΔX, the distance between the point (11) and the point (12) is ΔX, and the distance between the point (12) and the point (3). 2ΔX, the distance between point (3) and point (1) is A, the distance between point (1) and point (6) is ΔX, and the distance between point (6) and point (13) The distance is ΔX, and the distance between the point (13) and the point (8) is 2ΔX.

  In this case, the elapsed time Δt between time t8 and time t10 is obtained as follows.

Δt = (2ΔX / Vs) + twj + (ΔX / Vj) + twd + (2ΔX / Vs) + twj + (A / Vj) + twd + (ΔX / V1) + (ΔX / Vs) + (2ΔX / V2)
In this case, the scanning speed of the laser when drawing is started from the point (8) is expressed by the equation (9).

次に、図１４及び図１５を用いて、実施の形態２の描画制御装置３００において、処理対象のストローク片とＸ座標が同一の一行上のストローク片を描画する時刻と、処理対象のストローク片の描画を開始する時刻との相対時刻（経過時間）を算出する手法について説明する。

Next, in FIG. 14 and FIG. 15, in the drawing control apparatus 300 according to the second embodiment, the time for drawing a stroke piece on the same line as the stroke piece to be processed and the same X coordinate, and the stroke piece to be processed A method for calculating a relative time (elapsed time) with respect to the time at which the drawing is started will be described.

  FIG. 14 is a flowchart illustrating processing for calculating relative time in the drawing control apparatus 300 according to the second embodiment. The process illustrated in FIG. 14 is a process executed by the elapsed time calculation unit 309 of the drawing control apparatus 300 according to the second embodiment.

  FIG. 15 is a diagram illustrating strokes used for explaining processing for calculating relative time in the drawing control apparatus 300 according to the second embodiment.

  The elapsed time calculation unit 309 determines whether or not there is an immediately preceding stroke piece as a processing target stroke piece at a position where drawing is to be started (step S301). The immediately preceding stroke piece refers to a stroke piece drawn before the stroke piece to be processed. That is, step S301 is processing for determining whether or not the stroke piece to be processed is the first stroke piece in the bitmap image data.

  Here, whether or not there is a previous stroke piece is, for example, whether or not there is a stroke piece in a position where the X coordinate is small in the same line as the stroke piece to be processed, and the stroke to be processed. The determination may be made based on whether or not there is a stroke piece in a line whose Y coordinate is smaller than that of the piece.

  Here, for example, the point (3) shown in FIG. 15 corresponds to the stroke piece without the immediately preceding stroke piece.

  If it is determined in step S301 that there is a previous stroke piece (S301: YES), the elapsed time calculation unit 309 acquires the previous stroke piece information (S302). The elapsed time calculation unit 309 acquires the coordinates of both ends of the stroke piece as the stroke piece information. This is because the length of the stroke piece is required to calculate the relative time.

  The elapsed time calculation unit 309 determines whether or not the previous stroke piece is within the same stroke as the stroke piece to be processed (step S303). This is because when the immediately preceding stroke piece is not within the same stroke as the stroke piece to be processed, for example, there is an idle running section between the immediately preceding stroke piece and the stroke piece to be processed.

  When the elapsed time calculation unit 309 determines that the previous stroke piece is within the same stroke as the stroke piece to be processed (S303: YES), the drawing speed (laser scanning speed) of the previous stroke piece is determined. Obtain (step S304).

  Next, the elapsed time calculation unit 309 calculates the elapsed time from the drawing start position of the immediately preceding stroke piece (step S305). For example, in FIG. 15, when trying to draw a stroke piece starting from the point (1), the previous stroke piece is a stroke piece from the point (2) to the point (1). Finds the elapsed time Δt = ΔX / V using the distance ΔX of the stroke piece from the point (2) to the point (1) and the drawing speed V acquired in step S304.

  Next, the elapsed time calculation unit 309 calculates a relative time (step S309). The relative time is obtained as a time obtained by adding the elapsed time required for the immediately preceding stroke piece or the idling section to the time at the start point of the immediately preceding stroke piece or the idling section.

  In step S301, when there is no stroke piece immediately before (S301: NO), the relative time is set to 0 (step S310). Prior to that, since the stroke piece is not drawn and is the first stroke piece, the relative time is set to zero.

  In Step S303, when it is determined that the immediately preceding stroke piece is not within the same stroke as the stroke piece to be processed (S303: NO), the elapsed time calculation unit 309 acquires the free running distance (Step S303). In step S306, the idle speed is acquired (step S307), the standby time is acquired (step S308), and the flow proceeds to step S309. This is to calculate the elapsed time required for the idle section.

  Here, for example, in FIG. 15, the idle running section between point (5) and point (2) corresponds. The coordinates of the point (5) are (X, Y) = (X5, Y5), the coordinates of the point (2) are (X, Y) = (X2, Y2), the standby time at the point (5) is twj, Let the standby time in 2) be twd.

  The idle running time from point (5) to point (2) shown in FIG.

従って、点（５）において描画を終了してから、点（２）で描画を開始するまでの経過時間Δｔは、式（１０）で表される空走時間に、点（５）における待機時間をｔｗｊと、点（２）における待機時間をｔｗｄとを加えた時間になる。

Therefore, the elapsed time Δt from the end of drawing at the point (5) to the start of drawing at the point (2) is equal to the idle time represented by the equation (10) and the standby time at the point (5). Twj and the waiting time at the point (2) is twd.

  As described above, the elapsed time calculation unit 309 calculates the relative time. After that, the drawing control device 300 according to the second embodiment executes the processing after step S206 shown in FIG.

  FIG. 16 is a diagram illustrating an example of a drawing command generated by the drawing control apparatus 300 according to the second embodiment.

  The five strokes shown in FIG. 16A are the same as the five strokes shown in FIG. 9 and FIG. 11A, and the coordinates of the points shown in each stroke are shown in FIG. Same as coordinates.

  Here, as in the first embodiment, in the drawing command, the stroke thickness is t, the movement (idle) to the specified coordinates without laser irradiation is m, and the line drawing to the specified coordinates is d, waiting. Time is w (msec (milliseconds)), laser output (ratio to the default value of laser output (percentage (%))) is p, and scanning speed (ratio to the default value of scanning speed (percentage (%))) is s. And

  A drawing command for drawing the five strokes shown in FIG. 16A from the point (7) closest to the origin O in the uppermost row is as shown in FIG. 16B.

  In the drawing command shown in FIG. 16B, first, the scanning speed s is set to 100 (%), the stroke thickness t is set to 10 (points), and (X, Y) = (10 , 10) Run to the point (7) (m).

  Next, the laser output (p) is set to 100%, and straight line drawing is performed until (X, Y) = (60, 10) (d).

  Next, it runs idle to (X, Y) = (70, 10) (m), and draws a straight line to (X, Y) = (90, 10) (d). Thereby, up to the point (3) is drawn.

  Next, the standby time w is set to 50 (msec) at the point (3), and the vehicle runs idly to the point (1) where (X, Y) = (80, 20) (m).

  Since there is a stroke drawn on one line at the point (1), the laser scanning speed s is set to 500% of the default value Vs, and a straight line extends to the point (6) of (X, Y) = (70, 20). Drawing is performed (d).

  At point (6), since there is no stroke on one line, the laser scanning speed s is returned to 100%, and a straight line is drawn up to point (13) at (X, Y) = (60, 20) (d).

  Since there is a stroke on one line from the point (13), the laser scanning speed s is increased to 200 (%), and a straight line is drawn up to the point (9) of (X, Y) = (50, 20) ( d).

  At point (9), since there is still a stroke on one line, the laser scanning speed s is set to 167 (%), and a line is drawn up to point (8) where (X, Y) = (40, 20). (D).

  At point (8), since there is still a stroke on one line, the laser scanning speed s is set to 143 (%), and line drawing is performed up to point (4) where (X, Y) = (30, 20). (D).

  Next, the vehicle runs to the point (5) of (X, Y) = (20, 20) (m).

  Since there is a stroke on one line from the point (5), the laser scanning speed s is set to 128 (%), and a straight line is drawn up to the point (14) of (X, Y) = (10, 20). (D).

  Since there is no stroke on one line from the point (14), the laser scanning speed s is set to 100 (%), and a straight line is drawn up to the point (15) of (X, Y) = (0, 20). (D).

  As described above, four strokes can be drawn from the point (7) to the point (15) while adjusting the laser scanning speed s according to the elapsed time after the drawing of the stroke on one line is completed.

  A stroke located one line below the point (14) to the point (4) can be similarly drawn.

  In the above description, the case where the drawing target is a graphic represented by bitmap image data has been described. However, the drawing target may be a character. In particular, when drawing a character thickly, if the drawing control apparatus 300 according to the second embodiment performs drawing, the character can be drawn accurately in a short time.

<Embodiment 3>
FIG. 17 is a diagram illustrating table format data used in the drawing control apparatus according to the third embodiment.

The drawing control apparatus according to the third embodiment ^converts the calculated value of (1-e ^−kt ), which is a common term between the expression (5) in the first embodiment and the expression (7) in the second embodiment, into table format data. Is different from the drawing control apparatuses 20 and 300 of the first and second embodiments.

  Hereinafter, the difference will be mainly described.

  The data shown in FIG. 17 shows values calculated when the cooling constant k is set to k = 0.2 and the elapsed time t is 1 to 100 (msec (milliseconds)).

  In tabular data, the value is a discrete value. For this reason, the intermediate value can be approximated by linear interpolation. When accuracy is a problem using the value obtained by rough estimation, the error due to linear interpolation can be reduced by setting the discrete values more finely.

In the third embodiment, the case has been described in which the values of the terms included in Expressions (5) and (7) are calculated in advance and used as data in the table format. There may be a case where appropriate data cannot be drawn with the data value in the format. In such a case, if the calculated value of the (1-e ^−kt ) term is obtained using the cooling coefficient obtained in the experiment, accurate drawing can be performed. It is also possible to prepare a plurality of table format data in advance according to the environmental temperature and the properties of the thermal rewritable medium 50, and switch the table format data according to the environmental temperature and the properties of the thermal rewritable medium 50.

<Embodiment 4>
The drawing control apparatus according to the fourth embodiment simplifies the processing of the drawing control apparatus 20 according to the first embodiment, generates a stroke by performing a one-way scan regardless of whether there is a drawing target, and scan speed and idle running. The speed is set to the same speed, and the laser output is switched depending on the presence or absence of the previous stroke.

  Here, in the fourth embodiment, since drawing is performed by one-way scanning, a stroke piece that is adjacent on one line has a start point (or an end point) that has the same X coordinate as the start point (or end point) of the stroke piece that is the generation target of the drawing command. A stroke piece having an end point) generated on one line of a stroke piece that is a generation target of a drawing command.

  FIG. 18 is a diagram illustrating the order of laser one-way scanning when the drawing control apparatus according to the fourth embodiment performs drawing.

  In the fourth embodiment, the laser is scanned by one-way scanning, and a free running section is provided, and scanning is performed for all regions represented by XY coordinates from the origin O regardless of the presence or absence of a drawing target.

  Here, it is assumed that the origin O is at the point a1. The X axis is the horizontal direction (right is positive), and the Y axis is vertical (down is positive).

  In the fourth embodiment, the stroke A1 is drawn from the point a1 toward the point a2. Run idle from point a2 to point a3. The stroke A4 is drawn from the point a3 to the point a4. Run idle from point a4 to point a5. The stroke A3 is drawn from the point a5 to the point a6.

  Then, the vehicle runs idly from the point a6 to the point b1 as indicated by a dashed arrow. This enters the second line.

  In the second line, a stroke B1 indicated by a broken line is drawn from point b1 to point b2 from X = 0 toward the positive direction of the X axis (the right direction in FIG. 18). Run idle from point b2 to point b3. A stroke B2 indicated by a broken line is drawn from the point b3 to the point b4. And between points b4 and b5, although there is no drawing object, idle running is performed.

  In this case, the drawing control apparatus according to the fourth embodiment adjusts the laser output in three stages as an example. Here, it is assumed that the laser output has three stages of P2 (= default value Ps), P1 (50% of the default value Ps), and P0 (0%).

  Here, the section between point b1 and point b5 shown in FIG. Section 1 is a section between point a1 (b1) and point a1 in the X-axis direction. Section 2 is a section between point a2 and point a3 in the X-axis direction. Section 3 is a section between point a3 and point b2 in the X-axis direction. Section 4 is a section between point b2 and point a4 (b3) in the X-axis direction. The section 5 is a section between the point a4 (b3) and the point a5 in the X-axis direction. The section 6 is a section between the point a5 and the point b4 in the X-axis direction. The section 7 is a section between the point b4 and the point a6 (b5) in the X-axis direction.

  In the fourth embodiment, when the laser output is set as described above, the sections 2 and 5 are sections in which stroke pieces are drawn, and since there is no stroke piece on one line, the laser output is the strongest. Let P2 be the default value Ps. Sections 1, 3, and 6 are sections in which stroke pieces are drawn. Since there is a stroke piece on one line, the laser output is set to a weaker P1. In the sections 2, 5, and 7, since the stroke pieces are not drawn, the laser output is set to P0 (0%).

  In the fourth embodiment, laser scanning is performed also in a section where there is no drawing object, such as point b4 to point b5 shown in FIG. 18, and the laser output is selected from three stages of outputs P2, P1, and P0. A stroke is drawn by one-way scanning.

  As described above, in the fourth embodiment, when there is a stroke piece on one line, the laser output is uniformly set to P1 (50% of the default value) regardless of the elapsed time. For this reason, it is not necessary to calculate the laser output according to the elapsed time, and the processing can be simplified.

  Next, a drawing control process executed by the drawing control apparatus according to the fourth embodiment will be described with reference to FIG.

  FIG. 19 is a flowchart illustrating a drawing control process executed by the drawing control apparatus according to the fourth embodiment. The flowchart shown in FIG. 19 represents the drawing control method of the fourth embodiment. This drawing control method is realized by executing the drawing control program of the first embodiment.

  The drawing control apparatus according to the fourth embodiment is similar to the drawing control apparatus 20 according to the first embodiment. The main control unit 201, the stroke information generation unit 202, the stroke piece generation unit 203, and the drawing order determination unit illustrated in FIG. 204, a speed setting unit 205, an idle section setting unit 206, a standby time setting unit 207, an adjacent stroke determination unit 208, an elapsed time calculation unit 209, a laser output setting unit 210, a drawing command generation unit 211, and a data storage unit 212. The description will be given as including.

  The drawing control apparatus according to the fourth embodiment sets the drawing speed to the standard speed (Vs) (step S401). The process in step S401 is a process executed by the speed setting unit 205 of the drawing control apparatus according to the fourth embodiment.

  The drawing control apparatus according to the fourth embodiment calculates an elapsed time from the end of drawing of a stroke piece adjacent on one line to the start of drawing of a stroke piece for which a drawing command is currently being created (step S402). . Step S402 is a process executed by the elapsed time calculation unit 209 of the drawing control apparatus according to the fourth embodiment.

  For example, when the drawing control apparatus according to the fourth embodiment performs drawing from the point b1 shown in FIG. 18, the drawing time from the point a1 to the point a6, the standby time at the point a6, and the point a6 to the point b1. The total time of the idle running time and the waiting time at the point b1 is calculated as the elapsed time from the start of the drawing of the point a1 on the line of the point b1 to the start of the drawing of the point b1.

  Note that when there is no stroke piece on one line as when drawing of the point a1 is started, it is not necessary to calculate the elapsed time.

  Next, the drawing control apparatus of Embodiment 4 determines the laser output P1 (step S403). The process of step S403 is a process executed by the laser output setting unit 210 of the drawing control apparatus of the fourth embodiment. In Embodiment 4, since the laser output P1 is set to 50% of the laser output P2 (default value), the laser output setting unit 210 determines the laser output P1 to be an output value of 50% of the laser output P2.

  Next, the drawing control apparatus according to the fourth embodiment selects one row included in the bitmap image data from the upper side, and acquires all strokes included in the row to be drawn from now on (step S404). The process in step S404 is a process executed by the stroke information generation unit 202 of the drawing control apparatus according to the fourth embodiment. In the example of FIG. 18, when the second row is selected, the stroke information generation unit 202 has two strokes, a stroke B1 between the point b1 and the point b2 and a stroke B2 between the point b3 and the point b4. To get.

  Next, the drawing control apparatus according to the fourth embodiment acquires all strokes included in the previous line (step S405). The process in step S404 is a process executed by the stroke information generation unit 202 of the drawing control apparatus according to the fourth embodiment. In the example of FIG. 18, the stroke information generation unit 202 includes three strokes A1, a stroke between the points a1 and a2, a stroke A2 between the points a3 and a4, and a stroke A3 between the points a5 and a6. Get the stroke.

  Next, the drawing control apparatus according to the fourth embodiment divides a line to be drawn into a plurality of sections based on the strokes obtained in steps S404 and S405 (step S406). The process in step S406 is a process executed by the main control unit 201 of the drawing control apparatus according to the fourth embodiment.

  In step S406, the main control unit 201 moves the stroke included in the line to be drawn one line higher in accordance with the positional relationship between the stroke included in the line to be drawn and the stroke included in the line on the next line. The stroke of the line to be rendered is divided so that it can be divided into a section where a stroke exists in FIG.

  In the example illustrated in FIG. 18, the main control unit 201 divides a row in which the strokes B <b> 1 and B <b> 2 exist into a section 1 to a section 7.

  Next, the drawing control apparatus of Embodiment 4 selects one section from the side close to the origin O of the X axis among the plurality of sections divided in step S406 (step S407). The process in step S407 is a process executed by the main control unit 201 of the drawing control apparatus according to the fourth embodiment. In step S407, the flow is returned to step S407, which will be described later, and is repeatedly executed, so that one of the plurality of sections divided in step S406 is selected one by one from the side close to the origin O of the X axis. It is processing to do.

  Next, the drawing control apparatus of Embodiment 4 determines whether or not the section selected in step S407 is a drawing section (step S408). The process in step S408 is a process executed by the main control unit 201 of the drawing control apparatus according to the fourth embodiment. In FIG. 18, sections 1 to 3, section 5, and section 6 are drawing sections, and sections 4 and 7 are sections that do not perform drawing.

  If the drawing control apparatus according to the fourth embodiment determines in step S408 that the section selected in step S407 is not a drawing section (S408: NO), the laser output is set to P0 (0%) (step S410). ). The process of step S410 is a process executed by the laser output setting unit 210 and the idling section setting unit 206 of the drawing control apparatus of the fourth embodiment. Because this is a section in which drawing is not performed, the laser output is set to 0%, and the section is set as an idle running section. In this case, the section 4 and the section 7 correspond in FIG.

  If the drawing control apparatus according to the fourth embodiment determines in step S408 that the section selected in step S407 is a drawing section (S408: YES), the drawing control apparatus determines whether there is a stroke on one line. (Step S409). The process in step S409 is a process executed by the adjacent stroke determination unit 208 of the drawing control apparatus according to the fourth embodiment.

  If it is determined in step S409 that there is no stroke on one line (S409: NO), the drawing control apparatus according to the fourth embodiment sets the laser output to P2 (default value) (step S411). The process in step S411 is a process executed by the laser output setting unit 210 of the drawing control apparatus according to the fourth embodiment. This is because when drawing is performed when there is no stroke on one line, the laser output is set to P2 (100%) which is the default value. In this case, section 2 and section 5 correspond in FIG.

  If the drawing control apparatus according to the fourth embodiment determines in step S409 that there is a stroke on one line (S409: YES), the laser output is set to P1 (50% of the default value) (step S409). S412). The process in step S412 is a process executed by the laser output setting unit 210 of the drawing control apparatus according to the fourth embodiment. When drawing is performed when there is a stroke on one line, since the residual heat due to the drawing of the stroke on the one line performed immediately before remains in the thermal rewritable medium 50, the laser output is set to P1 (50 which is lower than the default value). %).

  When the processing of steps S410, S411, and S412 ends, the drawing control apparatus of the fourth embodiment stores the drawing command for the section in which the laser output is set in steps S410, S411, and S412 in the drawing command DB (step S413). . The process of step S413 is a process executed by the drawing command generation unit 211 of the drawing control apparatus of the fourth embodiment.

  The drawing command includes the laser scanning speed set in step S401, the laser output set in steps S410, S411, and S412 and the coordinates of both ends of the section.

  The drawing control apparatus according to the fourth embodiment determines whether or not drawing commands have been generated for all sections (step S414). The process in step S414 is a process executed by the main control unit 201 of the drawing control apparatus according to the fourth embodiment.

  Whether or not the drawing command has been generated for all the sections may be determined, for example, by comparing the coordinates of the end point of the section being processed with the coordinates of the end point of the line.

  If it is determined in step S414 that the drawing command has not been generated for all the sections in step S414 (S414: NO), the drawing control apparatus of the fourth embodiment advances the flow to step S407.

  Thereby, the process of step S408-S414 is performed about the following area.

  If the drawing control apparatus of Embodiment 4 determines in step S414 that a drawing command has been generated for all the sections (S414: YES), the flow proceeds to step S415.

  The drawing control apparatus according to the fourth embodiment determines whether or not processing has been completed for all rows (step S415). The process in step S415 is a process executed by the main control unit 201 of the drawing control apparatus according to the fourth embodiment. Whether or not the processing has been completed for all the rows may be determined, for example, by determining whether or not the Y coordinate of the row being processed has reached the bottom row of the bitmap image data.

  If the drawing control apparatus according to the fourth embodiment determines that the processing has not been completed for all the rows (step S415: NO), the flow returns to step S404. In step S404, the drawing control apparatus according to the fourth embodiment selects the next line, acquires the stroke in the line, and executes the processes in step S405 and subsequent steps.

  When the drawing control apparatus according to the fourth embodiment determines that the processing has been completed for all the rows (step S415: YES), the drawing control apparatus outputs a drawing command (step S416). The process of step S416 is a process executed by the drawing command generation unit 211 of the drawing control apparatus of the fourth embodiment. The drawing command generation unit 211 inputs a drawing command to the drawing device 10. Thereby, in the drawing apparatus 10, accurate drawing is performed by adjusting the output of the laser in accordance with the presence or absence of a stroke on one line.

  As described above, according to the drawing control device of the fourth embodiment, the laser output can be set according to the presence or absence of the stroke piece on one line, and the thermal rewritable is performed by drawing the stroke piece on one line. Even in a state where there is residual heat in the medium 50, it is possible to perform drawing accurately by adjusting the output of the laser.

  Further, as described above, the drawing control apparatus according to the fourth embodiment of the fourth embodiment uniformly sets the laser output to P1 (50% of the default value) when there is a stroke on one line. Compared with the case where the output of the laser is calculated according to the elapsed time as in the first and second embodiments, the processing can be simplified.

  In the above description, the mode in which the stroke is divided into sections has been described. However, the section described above may be handled as a stroke piece. In the first and second embodiments, the stroke piece has been described as having a certain length ΔX. However, the section of the fourth embodiment has various lengths depending on whether or not drawing is performed and whether or not there is a stroke on one line. In order to obtain the stroke piece, it can be handled as a stroke piece having a variable length.

<Embodiment 5>
The fifth embodiment is a modification of the drawing control apparatus according to the first to fourth embodiments, and is that the standby time is adjusted in order to wait for the temperature of the thermal rewritable medium 50 to be lowered to some extent. Different from the drawing control device.

  Since the thermal rewritable medium 50 has a cooling constant k corresponding to the material or the like, how much the temperature of the thermal rewritable medium 50 decreases after drawing a stroke in a portion under one line of the drawn stroke. It can be determined experimentally.

  For this reason, the drawing control apparatus of the fifth embodiment sets both the laser scanning speed and the laser output to default values (Vs, Ps), adjusts the standby time at the start point or end point of the idle running section, and is thermally rewritable. Wait for the temperature of the medium 50 to drop.

  Immediately after drawing a stroke on one line, when drawing a stroke on a line below that stroke, if the waiting time is extended and the temperature of the thermal rewritable medium 50 decreases, the scanning speed Vs (default value) Even when drawing is performed with the laser output Ps (default value), the influence of the residual heat can be suppressed and accurate drawing can be performed.

  In the drawing control apparatus according to the fifth embodiment, the standby time may be longer than in the first to fourth embodiments, so that the time required to complete all the drawing may be longer. In addition, since it is not necessary to adjust the scanning speed, the drawing process can be simplified as compared with the drawing control apparatuses of the first to fourth embodiments.

  As described above, the drawing control apparatus, the laser irradiation apparatus, the drawing control method, the drawing control program, and the recording medium on which the drawing control apparatus according to the exemplary embodiment of the present invention has been described have been specifically disclosed. The present invention is not limited to the embodiments, and various modifications and changes can be made without departing from the scope of the claims.

DESCRIPTION OF SYMBOLS 10 Drawing apparatus 11 Laser oscillator 12 Direction control motor 13 Direction control mirror 14 Optical lens 15 Condensing lens 20 Drawing control apparatus 31 CPU
32 Memory 33 CD-ROM drive 34 Network device 35 Hard disk 36 Input device 37 Display 50 Thermal rewritable medium 100 Laser marking device 201 Main control unit 202 Stroke information generation unit 203 Stroke piece generation unit 204 Drawing order determination unit 205 Speed setting unit 206 Empty Running section setting unit 207 Standby time setting unit 208 Adjacent stroke determination unit 209 Elapsed time calculation unit 210 Laser output setting unit 211 Drawing command generation unit 212 Data storage unit 300 Drawing control device 301 Main control unit 302 Stroke information generation unit 303 Stroke piece generation Unit 304 drawing order determination unit 305 speed setting unit 306 idling section setting unit 307 standby time setting unit 308 adjacent stroke determination unit 309 elapsed time calculation unit 310 laser output setting unit 3 1 drawing command generating unit 312 data storage unit

JP 2008-62506 A

Claims (12)

A drawing control apparatus that controls a drawing apparatus that draws a drawing target by irradiating a medium with a laser,
Stroke information generating means for generating stroke information representing a plurality of strokes for drawing the drawing object based on the shape information representing the shape of the drawing object;
Laser adjusting means for generating the output of the laser, the scanning speed, or the waiting time based on the stroke information generated by the stroke information generating means and the elapsed time between strokes;
A drawing command generating unit that generates a drawing command for controlling the drawing device based on the stroke information generated by the stroke information generating unit and the output, scanning speed, or standby time of the laser generated by the laser adjusting unit; A drawing control apparatus. The laser adjustment means includes
A determination unit that determines whether there is another stroke that is adjacent to one stroke and has a drawing order earlier than the one stroke;
A calculation unit that calculates an elapsed time from drawing by the other stroke to drawing by the one stroke;
The drawing control apparatus according to claim 1, further comprising: an output determination unit that determines an output of the laser based on a determination result of the determination unit and an elapsed time calculated by the calculation unit.   The drawing control apparatus according to claim 2, wherein the output determining unit decreases the output of the laser as the elapsed time is shorter. The laser adjustment means includes
A determination unit that determines whether there is another stroke that is adjacent to one stroke and has a drawing order earlier than the one stroke;
A calculation unit that calculates an elapsed time from drawing by the other stroke to drawing by the one stroke;
The drawing control apparatus according to claim 1, further comprising: a speed setting unit that sets a scanning speed of the laser based on a determination result of the determination unit and an elapsed time calculated by the calculation unit.   The drawing control apparatus according to claim 4, wherein the speed setting unit increases the scanning speed of the laser as the elapsed time is shorter. A stroke piece generating unit that divides the stroke represented by the stroke information generated by the stroke information generating unit into stroke pieces of a predetermined length;
The determination unit determines whether or not there is a stroke piece that is adjacent to one stroke piece included in the one stroke and is included in another stroke that is earlier in drawing order than the one stroke piece,
The drawing control apparatus according to claim 2, wherein the calculation unit calculates an elapsed time from drawing with the other stroke piece to drawing with the one stroke piece.   The drawing control apparatus according to claim 2, wherein the laser adjustment unit further includes a standby time setting unit that sets a standby time between strokes according to a determination result of the determination unit.   The drawing control device according to claim 7, wherein the standby time setting unit sets the standby time longer as the elapsed time calculated by the calculation unit is shorter. A laser oscillator for irradiating a laser;
A direction control mirror for controlling the irradiation direction of the laser irradiated by the laser oscillator;
A direction control motor for driving the direction control mirror;
A laser irradiation apparatus comprising: the drawing control apparatus according to claim 1, which controls irradiation output of the laser oscillator and drive control of the direction control motor based on the drawing command. A drawing control method in which a computer controls a drawing apparatus that draws a drawing target by irradiating a medium with a laser,
The computer
A stroke information generating step for generating stroke information representing a plurality of strokes for drawing the drawing object based on shape information representing the shape of the drawing object;
A laser adjustment step of generating the output of the laser, the scanning speed, or the standby time based on the stroke information generated in the stroke information generation step and the elapsed time between strokes;
Drawing command generation for generating a drawing command for controlling the drawing device based on the stroke information generated in the stroke information generating step and the output, scanning speed, or standby time of the laser generated in the laser adjustment step A drawing control method for executing the steps. A drawing control program for causing a computer to execute a drawing control process for controlling a drawing device that draws a drawing target by irradiating a medium with a laser,
The computer,
Stroke information generating means for generating stroke information representing a plurality of strokes for drawing the drawing object based on shape information representing the shape of the drawing object;
Based on the stroke information generated by the stroke information generating means and the elapsed time between strokes, the laser adjusting means for generating the laser output, the scanning speed, or the waiting time, and the stroke generated by the stroke information generating means A drawing control program that functions as a drawing command generating unit that generates a drawing command for controlling the drawing device based on the information and the output, scanning speed, or standby time of the laser generated by the laser adjusting unit.   The recording medium which recorded the drawing control program of Claim 11.

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