JP3376022B2 - Method and apparatus for producing hologram master - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for producing a hologram original plate, and more particularly, a method and an apparatus for producing a hologram original plate suitable for producing an original of a security hologram sticker for certifying an authentic article. Regarding

[0002]

2. Description of the Related Art Hologram stickers are used as a means for preventing counterfeiting of credit cards, bankbooks, cash vouchers and the like. In addition, hologram seals are used for products such as video tapes and luxury watches to prevent pirated copies from circulating. In addition, hologram stickers are also used for purposes such as decoration and sales promotion. In such a hologram sticker, a two-dimensional picture is often used as a motif instead of a three-dimensional stereoscopic image.

In order to produce such a hologram seal original plate, an optical hologram photographing method of forming interference fringes using a laser beam is usually used. That is, prepare a manuscript with a two-dimensional design motif and
The original is irradiated with one of the two branched laser lights, and the reflected light is interfered with the other branched laser light to record the interference fringes on the photosensitive material. After the hologram master plate is created in this manner, hologram seals can be mass-produced using the master plate by a pressing method.

[0004]

However, the above-mentioned conventional optical hologram photographing method has a problem that a clear hologram image cannot be obtained. That is, since the optically formed interference fringe is sensitive to vibration, it is necessary to perform hologram imaging in an environment in which vibration is completely eliminated. However, it is difficult to completely eliminate the vibration even when shooting with a vibration-proof table with considerable accuracy.
Therefore, so-called "blur" occurs in the recorded image of the interference fringes,
A bright hologram image with contrast cannot be obtained. Further, since the oscillation wavelength of the laser light used also fluctuates, spider glass noise cannot be avoided. As described above, since there is a problem of poor reproducibility in optical hologram photographing, it is difficult to make several same original plates.

Therefore, an object of the present invention is to provide a method and an apparatus for producing a hologram original plate which can obtain a clear hologram image and has good reproducibility.

[0006]

[Means for Solving the Problems] (1) In the first invention of the present application, a picture pattern having a plurality of closed areas each constituting a part of a picture is expressed by a contour line of each closed area, and the contour line The first step of creating contour line data indicating
Based on the second step of creating the grid condition data in which the line width, pitch, and arrangement angle of the grid lines forming the diffraction grating are set for each closed region of the picture pattern, and the contour line data and the grid condition data. A third step of generating a grid pattern in which grid lines of a predetermined line width are arranged at a predetermined pitch and a predetermined angle in each closed area of the picture pattern, and creating grid data indicating this grid pattern; Then, the fourth step of forming the lattice pattern on the physical original plate is performed, and the hologram original plate is created.

(2) The second invention of the present application is, in a hologram master producing apparatus, a pattern pattern having a plurality of closed regions each of which constitutes a part of a pattern is defined by a contour line of each closed region. Based on the input from the operator, the contour line data creation unit that creates the contour line data that expresses this contour line and the line width, pitch, and arrangement angle of the grating lines that form the diffraction grating, Based on the grid condition setting unit that creates the grid condition data set for each area, and the contour line data and the grid condition data, a grid line of a predetermined line width is formed in each closed area of the picture pattern at a predetermined pitch and a predetermined angle. A grid data generation unit that generates the arranged grid pattern and creates grid data indicating this grid pattern, and an original plate creation unit that forms the grid pattern on a physical original plate based on the grid data. Those digits.

(3) In the third invention of the present application, in the hologram master plate producing apparatus according to the second invention, the lattice condition setting section encloses one loop in the pattern pattern expressed by multiple loops. The grid condition data is created by setting each closed region or a region between two adjacent loops as an individual closed region.

(4) According to a fourth aspect of the present invention, in the hologram original plate producing apparatus according to the second aspect of the present invention, the lattice condition setting unit sets the lattice condition data for a plurality of adjacent closed regions. When performing, the operator inputs initial data indicating the lattice condition data for one closed region and variation data indicating the variation for this initial data, and regarding the lattice condition data for the other closed regions, , Is automatically set based on the initial data and the variation data.

(5) According to a fifth aspect of the present invention, in the hologram original plate producing apparatus according to the second aspect of the present invention, the lattice condition setting unit sets lattice condition data for a plurality of adjacent closed regions. When performing, the operator inputs the initial data indicating the lattice condition data for the first closed region and the final data indicating the lattice condition data for the second closed region, and the first closed region and the first closed region are input. The grid condition data for the closed area between the two closed areas is automatically set by interpolation based on the initial data and the final data.

(6) A sixth aspect of the present invention is the apparatus for producing a hologram original plate according to the second aspect of the invention, wherein when the lattice data producing section produces a lattice pattern for one closed region, the lattice condition is satisfied. Generate a parallel line at a predetermined pitch and a predetermined angle based on the data, find the intersection of this parallel line and the contour line of the closed region, define a line segment with this intersection as the end points, and then based on the grid condition data The thickening process is performed so that the line segment has a predetermined line width.

[0012]

[Operation] The feature of the method for producing a hologram master according to the present invention is that a diffraction grating pattern is generated by a computer and recorded as a hologram pattern on the master instead of the conventional optical hologram photographing method. is there.
That is, first, contour line data in which a picture pattern having a plurality of closed regions is expressed by the contour lines of each closed region is created. Then, the grid condition is set for each closed region. Specifically, the line width, pitch, and arrangement angle of the grating lines that form the diffraction grating are set as the grating condition for each closed region. What kind of grid condition is set is
Depending on the operator's instruction input, different grid conditions can be freely set for each closed region. The set grid conditions are output in the form of grid data. Thus, if the contour line data and the grid data can be created, the grid pattern can be generated based on these data. This grating pattern is composed of diffraction gratings generated under a predetermined grating condition for each closed region. Finally, this grid pattern is formed on the physical master. In this way, a diffraction grating pattern having a predetermined pattern as a motif is generated on the original plate. Since the lattices are formed under different conditions for each closed region, different diffraction effects are obtained for each closed region, and the motif of the original pattern can be recognized.

In short, according to the present invention, it is possible to create a hologram by a diffraction grating pattern generated by a computer without performing optical imaging.
If you save the contour line data and the grid data that you have created once, and then perform the original creation process again based on these data, you can obtain the exact same original plate, and you will get almost complete reproducibility. . Further, since it is not necessary to perform optical photographing, a clear hologram image can be obtained.

In general, the word "hologram" is used as a word indicating an image obtained by interference fringes. From such a meaning, the image formed on the original plate by the method of the present application is "hologram". It should be called "diffraction grating pattern" instead of "." However, since the anti-counterfeit seal mass-produced from this original plate is generally called a "hologram seal", in this specification, the "diffraction grating pattern" created on the original plate is also called the "hologram". Will be used.

[0015]

The present invention will be described below based on illustrated embodiments. FIG. 1 is a block diagram showing the basic configuration of a hologram master production device according to the present invention. The basic constituent elements of this device are a contour line data creation unit 1, a grid condition setting unit 2,
The grid data creation unit 3 and the original plate creation unit 4. The patterns and the like shown on the right of each block are conceptual diagrams showing the creations by each device.

The contour line data creating unit 1 has a function of expressing a picture pattern having a plurality of closed regions by the contour lines of the respective closed regions and creating contour line data indicating the contour lines. Specifically, a generally used drawing device (for example, a personal computer equipped with a drawing program) can be used as the contour line data creating unit 1. The picture pattern created here will be expressed as a motif in the final hologram master plate. The picture patterns created by a general drawing device are roughly classified into two types of data formats. The first type is a data format generally called "draw system", which expresses contour lines by vector data. The second type is a data format generally called "paint system" and represents the entire pattern in raster data. In the present invention, an image drawing device (CAD device) capable of creating a picture in a "draw type" data format is used. That is, the created picture pattern is represented by the contour line data. Various image forming apparatuses having such a function are known, and therefore detailed description thereof is omitted here. If a contour device including a scanner is used as the contour line data creation unit 1, it is possible to capture a picture pattern drawn on the paper surface.

FIG. 1 shows an example in which a simple picture pattern P consisting of three closed areas is created.
The contour line data creation unit 1 outputs such a picture pattern P in the form of contour line data C. In addition, in this embodiment, in order to efficiently perform the subsequent arithmetic processing, regarding the curved portion of the outline of the pattern,
This is approximated by a fine straight line, and each straight line is represented by vector data. Some drawing devices have a function of creating a pattern by a straight line and a curved line (for example, Bezier curve). However, for contour line data including such a curved line, approximation processing by a straight line should be performed. Good.

The grating condition setting unit 2 forms the lines of the grating lines forming the diffraction grating based on the input from the operator for each closed region specified by the contour line data created by the contour line data creating unit 1. It has a function of setting the width, the pitch, and the arrangement angle, and outputting this as grid condition data. For example, when the contour pattern data C as shown in FIG. 1 specifies a picture pattern P consisting of three closed areas ,,
, The grid line width, pitch, and arrangement angle of each grid line are set and outputted as the grid condition data Q. This lattice condition data Q is set based on the input from the operator. The lattice condition setting unit 2 is actually realized by mounting a predetermined program on a personal computer or a workstation. In the apparatus of the present embodiment, a picture pattern P having a closed area, is displayed on the display based on the given contour line data C, and is set by using an input device such as a mouse or a keyboard. The configuration is such that the grid condition data can be input while specifying the closed region. However, it is not always necessary for the operator to input all the grid condition data including the line width, pitch, and arrangement angle of the grid lines. For example, if the arrangement is made such that the line width of the grid lines is the same as the pitch, the line width input becomes unnecessary. Moreover, if the line width and the pitch are fixed to specific values, it is not necessary to input them one by one.

The lattice data creating section 3 is based on the contour line data created by the contour line data creating section 1 and the grid condition data created by the grid condition setting section 2 in each closed region of the picture pattern. Has a function of generating a grid pattern in which grid lines having a predetermined line width are arranged at a predetermined pitch and a predetermined angle, and creating grid data indicating this grid pattern. In the example shown in FIG. 1, the grid data D corresponding to the grid pattern L is created based on the contour line data C and the grid condition data Q. Here, an example is shown in which the line width and the pitch of the lattice lines are fixed and only the arrangement angle is changed for the three closed regions. The lattice data creation unit 3 can also be realized by actually mounting a predetermined program on a personal computer or a workstation. In the apparatus of this embodiment, the grid condition setting unit 2 and the grid data creation unit 3 are configured by the same device in terms of hardware. The grid data D may be image data in raster format or vector format as long as it is image data that can express the grid pattern L. However, considering the next step of giving the grid data D to the original creation unit 4, it is preferable to create the grid data D described in a format that the original creation unit 4 can handle.

The original creation unit 4 is a device having a function of forming a grid pattern on a physical original plate based on the grid data created by the grid data creation unit 3.
In the example of FIG. 1, the hologram original plate H in which the pattern corresponding to the lattice pattern L is physically formed is obtained. In the present embodiment, a charged particle beam drawing device is used as the original creation unit 4. More specifically, an electron beam drawing apparatus for making a photomask is used. Since the line width and the pitch of the lattice lines on the lattice pattern L are sufficiently small values (for example, about 1 μm) to cause the diffraction phenomenon, the electron beam drawing apparatus is required to generate such a fine pattern. Very suitable. However, the original plate creating unit 4 is not limited to the charged particle beam drawing device, and for example, after outputting an enlarged image of the lattice pattern L on a film by a printer or the like, it is reduced by an optical method. Then, a means for obtaining a hologram original plate may be used.

As described above, according to the method of the present invention, data processing by a computer can be performed up to the step of preparing the grid data D corresponding to the grid pattern L.
Since a physical diffraction grating is formed on the hologram master H based on the grating data D, reproducibility is extremely improved. That is, if the same lattice data is used, almost the same hologram master plate can be obtained. Further, the image on the hologram original plate is not an optically formed interference fringe image but a diffraction grating pattern generated by a computer, so that it becomes very clear. From this point of view, what is finally created by the present invention is not a “hologram master plate” in a pure sense but a “pseudo hologram master plate” or a “diffraction grating pattern”. As described above, in this specification, the term “hologram original plate” is used.

Next, the operation of the apparatus shown in FIG. 1 will be described in detail based on an example using a concrete pattern pattern. Here, consider a case where a hologram master is created based on a motif as shown in FIG. The motif shown in FIG. 2 is 3
It is a relatively simple motif composed of three closed regions. It is of course possible to use such a simple motif as it is as a picture pattern. In this case, similarly to the example shown in FIG. 1, the lattice patterns are respectively generated inside the three closed regions. However, as a hologram sticker for preventing forgery, it is preferable to use a picture pattern as complicated as possible. Therefore,
In this embodiment, a method of forming a picture pattern by a multiple loop is adopted. That is, the pattern pattern shown in FIG. 3 is used for the motif shown in FIG. This picture pattern has three groups G
1, G2, G3, and each of these groups corresponds to the closed region in the motif shown in FIG. However, the motif in FIG. 2 expresses a picture with a single contour line, whereas the pattern in FIG. 3 expresses a picture with multiple loops.

By adopting such a pattern expression by multiple loops, the number of closed areas can be increased and the pattern can be complicated. For example, in the pattern of FIG. 3, five closed regions are formed by the five-fold loops in the groups G1 and G2, respectively, and four closed regions are formed by the four-fold loop in the group G3. A total of 14 closed regions are formed. In short, the area surrounded by the innermost loop or adjacent 2
The area between two loops can be treated as one closed area. Therefore, if a different grid pattern is set for each closed region, a quite complicated hologram image can be generated. The operation of creating a picture pattern including such multiple loops by the drawing device is relatively simple. That is, first, a basic motif as shown in FIG. 2 is created, and subsequently, for each part of each closed region, a reduced outer loop is sequentially arranged as an inner loop. .

Now, the following description will be continued on the assumption that the contour line data creating section 1 has created a pattern pattern composed of multiple loops as shown in FIG. In addition, in the picture pattern including the multiple loops, the loop itself constitutes the contour line, and as described above, the curved portion is approximated by a set of fine straight lines. The contour line data C output from the contour line data creation unit 1 is, in the end, a representation of each loop by vector data of linear approximation.

In the grid condition setting unit 2, for each of the 14 closed regions forming the picture pattern shown in FIG.
The grid conditions will be set. This setting procedure will be described based on the flowchart of FIG. In the device of this embodiment, two methods are prepared as the method for setting the lattice conditions. The first method is a loop unit (one closed region unit) setting, and the second method is a group unit (a plurality of closed region units) setting. First, step S
In 1, the operator selects a setting method. For example, when input is made instructing the setting method in loop units, the work of designating the first loop in step S2 and designating the second loop in step S3 can be performed. Specifically, when the group G1 is set on a loop-by-loop basis, two adjacent loops among the five loops L1 to L5 are designated, as shown in FIG. For example, when the loop L3 in FIG. 5 is designated as the first loop and the loop L4 is designated as the second loop, the closed region between the two loops is selected as the setting target.

In the device of this embodiment, the grid condition setting unit 2 includes a color display device, and during the work of setting the grid condition, the pattern pattern as shown in FIG. 3 is displayed by this display device. I have to. The operator can use the input device such as a mouse or a keyboard to make an input designating a specific loop while observing this display. Further, in this device, each time the operator designates a loop, only the designated loop is displayed in a different color. For example, when the loops L3 and L4 are designated, the display colors of these two loops change. This allows the operator to visually recognize which loop is currently specified.

In this way, when the specific closed area is specified by the loop specification, conditions are set for the specific closed area to be set in step S4. Specifically, the line width of the grid lines generated in the closed region, the pitch,
The placement angle is input. For example, loops L3, L
If a grid line as shown in FIG. 6 is generated in the closed region surrounded by 4, the line width d, the pitch p, and the arrangement angle θ (in this example, the angle when the X axis is the reference axis) You can make an input to specify. However, line width d and pitch p
Is always fixed to a predetermined value, the placement angle θ
You only have to specify The line width d and the pitch p are parameters that determine the color of light observed from the hologram, and the arrangement angle θ is a parameter that determines the direction in which the light is observed.

Subsequently, the grid condition setting unit 2 performs step S
In 5, the pseudo lattice lines are displayed in the area where the condition setting is completed. For example, as shown in FIG. 6, the loop L3,
When the condition setting for the closed area surrounded by L4 is completed, a pseudo lattice line is displayed in the closed area on the display device, as shown in FIG. Since the actual line width d and the pitch p of the grid lines are values of about 1 μm, if the grid lines are displayed under the conditions actually set, the grid lines cannot be displayed at the resolution of the display device. Therefore, the pseudo grid lines in which the line width d and the pitch p are expanded to many times the actual size and the actual grid lines are thinned to reduce the number of lines are arranged at an angle θ (this can be displayed as set).
Is displayed with. The operator looks at this display and
It is possible to recognize which closed region the condition setting has been completed, and it is possible to recognize the arrangement angle θ set for the closed region. A function to change the display magnification on the display screen is provided,
On a sufficiently enlarged screen, the line width d of the actual grid line
Alternatively, the display may be performed according to the pitch p. Finally, through step S6, the procedure returns to step S1. By repeating this procedure, the grid condition can be set for each closed region.

The two loops designated in steps S2 and S3 are not always necessary. For example, when the closed region inside the loop L1 in FIG. 5 is set as the condition setting target, the target closed region is specified only by designating the loop L1 in step S2. Alternatively, if the loop previously designated as the first loop is automatically handled as the second loop next time, the first loop may be newly designated every time.
Such a designation method can be appropriately changed in consideration of operability.

On the other hand, in step S1, if an input for instructing a setting method for each group is performed, it becomes possible to collectively specify a plurality of closed regions. First, step S7
In, specify the group. Here, it is assumed that the group G1 in the picture pattern shown in FIG. 3 is designated. Then, in step S8, the condition is set,
At this time, the condition setting for the five closed regions formed by the loops L1 to L5 is collectively performed. Now, let's assume that the user intends to set conditions such as the table shown in FIG. In this condition setting, the line width is constant at 0.6 μm and the pitch is constant at 1.2 μm in any closed region. However, regarding the arrangement angle, the closed region (the inner region of the loop L1) is 0 °, and the angle increases by 10 ° as it goes to the outer closed region.
The closed area (the outermost area surrounded by the loops L4 and L5) is 40 °.

When such a regular condition setting is performed, it is convenient to set in group units. As a method of setting conditions, two methods are prepared in this embodiment. The first method is a method of designating an initial condition and a variation. In the case of the example shown in FIG. 8, 0 ° is designated as the initial condition of the arrangement angle with respect to the closed region, and the variation is +1.
You can specify 0 °. The second method is a method of designating an initial condition and a final condition. In the case of the example shown in FIG. 8, 0 ° is designated as an initial condition of the placement angle for the closed region, and the placement is performed for the closed region. 40 ° as the final condition of the angle
Should be specified. For the closed region between and, the placement angle is automatically set by linear interpolation. In addition to the initial condition and the final condition, a method of designating an intermediate condition is also possible. For example, as shown in FIG. 9, when the closed regions to are continuously arranged, the initial condition of the arrangement angle is −30 with respect to the closed region.
By specifying 0 °, the same -30 ° as the final condition of the placement angle for the closed region, and 30 ° as the intermediate condition of the placement angle for the closed region, the closed region By linearly interpolating between the closed regions and, it is possible to automatically set the arrangement angles of all the closed regions.

In this way, the operator continues to set lattice conditions while looking at each closed region of the picture pattern displayed on the display device until pseudo lattice lines are displayed in all closed regions. When all the grid conditions are set, the set conditions are output from the grid condition setting unit 2 as grid condition data Q. In the apparatus of this embodiment, both the contour line data C output from the contour line data creation unit 1 and the grid condition data Q output from the grid condition setting unit 2 are both stored in the floppy disk in a file format. I am trying.

As described above, when the contour line data C and the grid condition data Q are prepared in the file format on the floppy disk, they are input to the grid data creating unit 3. The grid data creation unit 3 creates a grid pattern based on these data and outputs this in the form of grid data D. Hereinafter, an example of a specific method of the grid pattern creation processing by the grid data creation unit 3 will be described. Here, for convenience of explanation, the loop L1 of the pattern patterns shown in FIG.
The process of creating a lattice pattern for a closed area surrounded by is taken as an example. The basic procedure of this processing is to generate parallel lines at a pitch p and an arrangement angle θ based on the grid condition data Q, find an intersection of this parallel line and the loop L1 (a contour line of the closed region), and set this intersection at both end points. The line segment to be defined is defined and the line width d based on the grid condition data Q is applied to the line segment to perform a thickening process.

In this embodiment, two different processes are performed depending on the size of the arrangement angle θ. First, in the case of −45 ° ≦ θ ≦ 45 °, parallel lines are generated as follows. That is, as shown in FIG.
The coordinate value of the center point A for the target closed area (x0,
y0) is calculated. As described above, in this embodiment, the contour line data are all composed of vector data by linear approximation, and the loop L1 shown in FIG.
In reality, it is represented by a polygon rather than an ellipse. Therefore, the barycentric position of each vertex forming this polygon may be obtained by calculation, and this barycentric position may be used as the coordinate value (x0, y0) of the center point A. And this center point A
A straight line that passes through (x0, y0) and whose inclination is the arrangement angle θ set as the grid condition is obtained, and a plurality of straight lines represented by the following equations are obtained with this straight line as a reference.

Y = tan θ (x−x0) + y0 + dy · n dy = p / cos θ where p is the pitch set as the lattice condition,
n is an integer of 0, ± 1, ± 2, ... As a result,
A plurality of parallel lines as shown in FIG. 11 will be obtained.
A straight line of n = 0 is a reference straight line passing through the center point A,
A plurality of straight lines intersecting with the loop L1 are obtained on both sides of this. A straight line that does not intersect the loop L1 is not necessary.

Next, the intersections of these parallel lines and the loop L1 are obtained, and the line segment having these intersections as the end points is defined.
For example, for a straight line corresponding to n = 0, two intersections A1 (x1, y1), A2 (x
2, y2) is obtained, and a line segment m having these two points as endpoints can be defined.

Next, a thickening process is performed to give the line segment m a predetermined line width d set as a grid condition. The thickening process is a process of giving a width to a geometrical line segment having no width element, and is actually a process of replacing the line segment with an elongated quadrangle. Here, in particular, a method of replacing with an elongated parallelogram will be described. Further, in order to simplify the calculation, a case where the condition that line width d = pitch p / 2 is set is taken as an example. Now, as shown in FIG. 12, when a line segment m having both end points A1 (x1, y1) and A2 (x2, y2) is defined, a process of replacing the line segment m with an elongated parallelogram is performed. Consider when to do it. In this case, the following four vertices are calculated.

(X1, Y1) = (x1, y1 + dy / 4) (X2, Y2) = (x1, y1-dy / 4) (X3, Y3) = (x2, y2-dy / 4) (X4, Y4 ) = (X2, y2 + dy / 4) As a result, a parallelogram as shown in FIG. 13 is obtained from these four vertices. In this parallelogram, all the short sides are parallel to the Y axis. When a total of five parallel lines are obtained as shown in FIG. 11, five parallelograms g1 to g5 whose short sides are all parallel to the Y-axis are obtained as shown in FIG. Become. In the figure, the ratio of the short side to the long side of these parallelograms is not so large, but in reality, the short side has a length of the order of about 1 μm, and the long side is 1
The length is generally on the order of mm. Therefore, these parallelograms become very elongated parallelograms that can be regarded as line segments when viewed macroscopically.

On the other hand, 45 ° <θ <90 °, or −
When 90 ° <θ <−45 °, parallel lines are generated as follows. First, as in the case described above, the coordinate value (x0, y0) of the center point A as shown in FIG. 10 is calculated. Then, a straight line that passes through the center point A (x0, y0) and whose inclination is the arrangement angle θ set as the grid condition is obtained, and with this straight line as a reference, a plurality of formulas shown by the following equations are obtained. Find a straight line.

X = tan θ ′ (y−y0) + x0 + dx · n dx = p / cos θ ′ where θ ′ = 90 ° −θ (where 45 ° <θ <90 °
), Θ ′ = − (90 ° + θ) (where −90 ° <
θ <−45 °). As a result, a plurality of parallel lines as shown in FIG. 15 are obtained.

Next, the intersection point of these parallel lines and the loop L1 is obtained, and the line segment m having these intersection points as the end points is defined,
A thickening process is performed on this. For example, as shown in FIG. 16, when a line segment m having both end points (x1, y1) and (x2, y2) is defined, the following four vertices are obtained for this line segment m, and the line Replace the minute m with this elongated parallelogram with four vertices.

(X1, Y1) = (x1-dx / 4, y1) (X2, Y2) = (x1 + dx / 4, y1) (X3, Y3) = (x2 + dx / 4, y2) (X4, Y4) = (X2-dx / 4, y2) In this parallelogram, the short sides are all parallel to the X axis. When a total of 7 parallel lines are obtained as shown in FIG. 15, seven parallelograms g1 to g7 whose short sides are all parallel to the X axis are obtained as shown in FIG. Become. It should be noted that these parallelograms also become very elongated parallelograms that can be regarded as line segments when viewed macroscopically.

The lattice pattern forming method for the closed region surrounded by the loop L1 has been described above, but the lattice pattern can be formed for the closed region surrounded by the two loops by substantially the same method. For example, as shown in FIG. 18, for the closed region surrounded by the loops L3 and L4,
Since four intersection points Q1 to Q4 are obtained for one straight line, the parallelogram ga is created by the thickening process for the line segment Q1Q2, and the parallelogram gb is created by the thickening process for the line segment Q3Q4. Good. In this way, if a grid pattern of parallelograms can be created for all closed regions, this grid pattern is output as grid data D. The original making unit 4 forms a physical lattice pattern based on the lattice data D, and makes a hologram original H.

After all, in the above-mentioned method, each grid line is formed by a very elongated parallelogram. Moreover, two types of parallelograms are used depending on whether or not the arrangement angle θ exceeds ± 45 °. That is, the short sides of the first parallelogram are parallel to the Y axis, and the short sides of the second parallelogram are parallel to the X axis. In this way, the reason why a parallelogram whose short side is parallel to any coordinate axis is created is for the convenience of the original creation process by the original creation unit 4. As described above, in this embodiment, the electron beam writing apparatus for making a photomask is used as the original making unit 4. With this drawing apparatus, it is much more efficient to draw a parallelogram in which a pair of opposite sides are parallel to one of the coordinate axes than to draw an arbitrary quadrangle. This is because drawing is performed while scanning the spot of the electron beam in each coordinate axis direction. Therefore, if a parallelogram is created by the method as described above, it is possible to draw very efficiently.

The present invention has been described above based on the illustrated embodiment, but the present invention is not limited to this embodiment and can be implemented in various modes other than this. For example, in the above-described embodiment, a very elongated parallelogram is used as the grid line, but this is for improving the drawing efficiency in the electron beam drawing apparatus for making a photomask, and is essential in the present invention. It is not a matter of.
Therefore, a very long and narrow rectangle may be used as the grid line. Further, in the block diagram shown in FIG. 1, the contour line data creation unit 1, the grid condition setting unit 2, and the grid data creation unit 3 are shown as separate components, respectively, but they are exactly the same in terms of hardware. It may be composed of a computer system.

[0046]

As described above, according to the method and apparatus for producing a hologram master according to the present invention, a diffraction grating pattern is generated by a computer, and this is recorded as a hologram pattern on the master. And a clear hologram image is obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of an apparatus for producing a hologram master according to the present invention.

FIG. 2 is a diagram showing an example of a motif that is a basis of a hologram pattern.

FIG. 3 is a diagram showing a pattern pattern obtained by expressing the motif shown in FIG. 2 in a multiple loop.

FIG. 4 is a flowchart illustrating a processing procedure of a grid condition setting unit 2 in the device shown in FIG.

5 is a partially enlarged view of the picture pattern shown in FIG.

FIG. 6 is a diagram showing lattice conditions defined in one closed region of the picture pattern shown in FIG.

7 is a diagram showing an example of a pseudo lattice line display process of step S5 in the flowchart shown in FIG.

8 is a diagram showing an example of a condition setting process of step S8 in the flowchart shown in FIG.

9 is a diagram showing another example of the condition setting process of step S8 in the flowchart shown in FIG.

FIG. 10 is a grid data creating unit 3 in the device shown in FIG.
It is a figure which shows the center point determination processing by.

FIG. 11 is a grid data creation unit 3 in the apparatus shown in FIG.
It is a figure which shows the parallel line generation process by.

12 is a diagram showing a line segment determination process based on the parallel lines shown in FIG.

FIG. 13 is a grid data creation unit 3 in the device shown in FIG.
It is a figure which shows the thickening process by.

14 is a diagram showing a state in which the thickening process is completed for each line segment obtained based on the parallel lines shown in FIG.

FIG. 15 is a grid data creation unit 3 in the device shown in FIG.
It is a figure which shows another parallel line generation process by.

FIG. 16 is a grid data creation unit 3 in the device shown in FIG.
It is a figure which shows another thickening process by.

17 is a diagram showing a state in which the thickening process has been completed for each line segment obtained based on the parallel lines shown in FIG.

FIG. 18 is a diagram showing a grid data creation process for a closed area surrounded by two loops.

[Explanation of symbols]

1 ... Contour data creation unit 2 ... Lattice condition setting section 3 ... Lattice data creation unit 4 ... Original edition department ~ ... Closed area A ... Center point C ... Contour data G1 to G3 ... Groups that make up a picture pattern D ... Lattice data H: hologram original L ... Lattice pattern L1 to L5 ... Loop (contour line of closed area) P ... Picture pattern Q: Lattice condition data Q1-Q4 ... intersection d ... Line width of grid line g, ga, gb, g1 to g7 ... Parallelogram m ... line segment p ... Pitch of grid lines θ: Arrangement angle of grid lines

Claims (6)

(57) [Claims] 1. A pattern pattern having a plurality of closed areas, each of which constitutes a part of a pattern, is expressed by a contour line of each closed area, and contour line data indicating the contour line is created.
And a second step of creating grating condition data in which the line width, pitch, and arrangement angle of the grating lines forming the diffraction grating are set for each closed region of the picture pattern, the contour line data, and the Based on the grid condition data and
A lattice pattern in which lattice lines having a prescribed line width are arranged at a prescribed pitch and a prescribed angle within each closed region of the picture pattern is generated, and lattice data indicating the lattice pattern is created.
And a fourth step of forming the lattice pattern on a physical original plate based on the lattice data, the method of producing a hologram original plate. 2. A contour line data creating section for expressing a pattern pattern having a plurality of closed regions each of which constitutes a part of the pattern by a contour line of each closed region and creating contour line data indicating the contour line. A grating condition setting unit that creates grating condition data in which the line width, pitch, and arrangement angle of the grating lines that form the diffraction grating are set for each closed region of the pattern based on the input from the operator; Based on the line data and the grid condition data,
A grid data creation unit that creates a grid pattern in which grid lines of a predetermined line width are arranged at a predetermined pitch and a predetermined angle in each closed region of the picture pattern, and creates grid data indicating the grid pattern; Based on the above, there is provided an original plate creating unit for forming the lattice pattern on a physical original plate, and a hologram original plate creating apparatus. 3. The creating apparatus according to claim 2, wherein for the picture pattern represented by multiple loops, the grid condition setting unit defines an area surrounded by one loop or an area between two adjacent loops. An apparatus for producing a hologram master plate, which produces lattice condition data for each closed region. 4. The creating device according to claim 2, wherein when the grid condition setting unit sets grid condition data for a plurality of closed regions arranged adjacent to each other, the grid condition for one closed region is set. The initial data indicating the data and the variation data indicating the variation with respect to the initial data are input from the operator, and the grid condition data for other closed regions are automatically calculated based on the initial data and the variation data. 1. An apparatus for producing a hologram master plate, which has a function of dynamically setting. 5. The creating apparatus according to claim 2, wherein when the grid condition setting unit sets grid condition data for a plurality of closed regions arranged adjacent to each other, the grid for the first closed region is set. Initial data showing condition data and second
End data showing the grid condition data for the closed region of, and the grid condition data for the closed region between the first closed region and the second closed region, the initial data And a hologram original plate creating apparatus having a function of automatically setting by interpolation based on the final data. 6. The creating apparatus according to claim 2, wherein the grid data creating unit creates parallel lines at a predetermined pitch and a predetermined angle based on the grid condition data when generating a grid pattern for one closed region. Then, the intersection of this parallel line and the contour line of the closed region is obtained, and a line segment whose endpoints are the intersection is defined, and a thickening process for giving a predetermined line width based on the grid condition data to the line segment is performed. An apparatus for producing a hologram original plate, which is characterized by performing.