JPH0449044B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a pattern moving device that is necessary for inspecting the shape and pattern applied to a product, particularly for inspecting the quality of a stamp applied to the surface of an IC package. Regarding.

[Conventional technology]

Conventionally, in order to inspect the shape etc. applied to a product using a CRT etc., a reference product is set, the shape etc. applied to this reference product is imaged with a video camera, and this video signal is converted into a binary signal. A standard pattern is obtained by converting it into a standard pattern (hereinafter referred to as a binary standard pattern), and the sum of the number of bits of this standard pattern is stored in advance as the area of the standard pattern. The area of the object pattern is calculated by binarizing the video signal to obtain the object pattern (hereinafter, the binary object pattern is referred to as the object pattern) and calculating the sum of the number of bits.
This area is compared with the area of a reference pattern stored in advance, and if the two areas match, the product is determined to be non-defective.

However, this method only compares the area of the reference pattern and the area of the subject pattern, so if the subject pattern itself has concave and convex parts and the area increases and decreases cancel each other out, There is a problem in that the patterns are determined to be the same even though they do not match.

In order to eliminate such problems, it is absolutely necessary to check the conformity of the shape of the reference pattern and the subject pattern, and for this purpose it is necessary to overlap the subject pattern and the reference pattern. Conventionally, as a means for matching these patterns with each other, a microcomputer compares and calculates the relationship between a pre-stored reference pattern and the subject pattern, and calculates the amount of deviation (number of bits) of the subject pattern with respect to the reference pattern. After calculating each of the horizontal, vertical, and rotational directions, a command is issued to correct the amount of deviation, and based on this command, the servo motor of the X-Y stage is moved to bring the subject pattern to the specified position. It was being set.

[Problems to be Solved by the Invention] However, moving the setting position of the subject using a servo mechanism based on command signals from a microcomputer is slow and cannot process a large amount of flowing product. There is also a method of moving one of the reference pattern or the subject pattern on a semiconductor memory using software processing to match the other without using mechanical means such as a servo mechanism. has a huge number of pixels (approximately 512 x 512), so it would take a lot of time to examine each memory corresponding to each pixel, and this method was also not suitable for inspecting and processing a large number of products. . The present invention has been made in view of the current situation, and aims to speed up inspection by performing pattern movement required during pattern inspection using a hardware method without relying on software methods. It is intended to include

[Means to solve the problem]

In order to solve the above problems, the present inventor completed the present invention through the following procedure.

First, the basic idea of the present invention will be explained using the attached conceptual diagram. The ultimate purpose of the present invention is to determine the quality of the test object pattern by superimposing the reference pattern shown on the left side on the test object pattern shown on the right side as shown in FIG. Defects in the object pattern include, for example, defects a and protruding stains b, and it is an object of the present invention to provide a device that can detect these defects a and stains b.

The reference pattern and the subject pattern are each stored separately on a semiconductor memory, and the superposition of the reference pattern onto the subject pattern is performed on the semiconductor memory inside the apparatus. At this time, if the placement position of the reference pattern and the placement position of the subject pattern in each memory match, you can simply superimpose them and compare them, but in most cases, the placement positions of both patterns in the memory will not match. First, as shown in FIG. 2, the subject pattern is shifted from the reference pattern in the rotational direction and in the horizontal and vertical directions. Therefore, if you want to superimpose the reference pattern in the example on the subject pattern, first rotate the reference pattern by θ clockwise around the upper left P of the display screen, as shown in Figure 3A. After matching the slope to the slope of the subject pattern, the third
As shown in Figure B, it is necessary to move by X in the horizontal direction and by Y in the vertical direction. Of course, although not shown,
The reference pattern may be first moved in the horizontal and vertical directions and then rotated. The gist of the present invention is to perform this movement in the rotational direction, horizontal direction, and vertical direction by hardware processing.

Note that a known method can be adopted as a method for detecting how far the reference pattern deviates from the subject pattern in each of the rotational direction, horizontal direction, and vertical direction, and the present invention is based on this known method. The feature is that the position of the reference pattern on the memory is moved by hardware using the rotational direction deviation angle θ, horizontal direction deviation It is.

By the way, rotational movement is particularly troublesome in pattern movement. As a result of intensive study on a method that can simplify movement in the rotational direction, the present invention has been developed by replacing rotational movement with horizontal movement and vertical movement of each dot constituting the reference pattern. If we approximately understand that each collection of dots is a rotated version of the original reference pattern, then by simply adding the amount of horizontal movement and the amount of vertical movement to the address of each dot, we can create the entire pattern as if it were a rotation of the original reference pattern. We noticed that the same result could be obtained by rotating the . The concept of this method will be briefly explained below using diagrams.

For example, if we consider a case where an L-shaped pattern existing on a display screen with 14 dots in the horizontal direction and 14 dots in the vertical direction is rotated, the state of the pattern before the rotation is configured to configure the display screen as shown in Figure 4. Therefore, the pattern after rotational movement is also expressed by a collection of dots as shown in FIG. 4B. Therefore, when comparing the patterns in Figure 4 A and B, the pattern as a whole is in a rotated state, but when looking at each dot that makes up the pattern, the dots move horizontally and vertically. It can be seen as progressing. The movement of each dot depends on the distance from the center of rotation P. For example, in the case of horizontal movement, as shown in Fig. 5, the dot moves one dot at a position α dot advanced in the vertical direction, and tanθ=1/α. A relationship is established. From this relationship, it can be easily understood that when n×α dots are advanced in the vertical direction, n dots are moved in the horizontal direction. Similarly, for vertical movement, move one dot at the position where β dot has advanced in the horizontal direction, and tanθ=
A relationship of 1/β holds true. Usually α=β.
Based on this idea, the rotational movement of the pattern shown in Figure 4 A is as shown in Figure 4 B,
This is possible by moving one dot horizontally for every α dot that moves vertically from the rotation center P, and by moving one dot vertically for every β dot that moves horizontally from the rotation center P. I understand that. Incidentally, rotational movement using such a method naturally includes an error, but if the number of dots forming the screen is sufficiently large and the angle of rotational movement is small, this error can be substantially ignored. Particularly in the case of seal inspection on the surface of a semiconductor package, to which the present invention is intended, there is no problem at all because the rotational deviation of character and number patterns is extremely small.

By the way, when performing rotational movement using the above method, a problem arises in how to count the distance from the rotation center P of each dot composing the pattern. In the present invention, a horizontal synchronizing signal and a horizontal dot clock, which are signals for creating a display screen, are used as the counting means.

For example, it has a display area of 512 x 512 dots.
When targeting a CRT, the synchronization signals supplied to the CRT are, as shown in Figure 6, a vertical synchronization signal c, which is a screen switching signal, followed by a horizontal synchronization signal d, which is a switching signal to the next scanning line. 512 consecutive horizontal dot clocks e are oscillated between the detection of a certain horizontal synchronization signal d and the detection of the next horizontal synchronization signal d. The correspondence relationship between the horizontal synchronizing signal d and the horizontal dot clock e and the CRT screen is as follows.
They have the relationship as shown in the figure. Therefore, the position that has advanced by α dots in the vertical direction can be detected by counting α horizontal synchronizing signals d, and the position that has advanced β dots in the horizontal direction can be detected by counting β horizontal dot clocks e. This can be done by doing this. In this way, in the present invention, the rotation center P
It was decided to detect the distance from the center by counting the number of horizontal synchronizing signals d and horizontal dot clocks e.

The rotational movement of the pattern is completed according to the principle described above, but the pattern that has completed the rotational movement is in the fourth position.
As shown in Figure C, all moving operations can be completed by moving the X dot in the horizontal direction and the Y dot in the vertical direction.

The present invention, which has been made based on the above idea, includes a reference pattern storage means A that stores a reference pattern in advance, and a reference pattern stored in the reference pattern storage means A that compares the subject pattern. Depending on the deviation of the pattern from the subject pattern in the rotational direction, horizontal and vertical directions, commands are given to move the reference pattern in the rotational direction to superimpose it on the subject pattern, and to make parallel movements in the horizontal and vertical directions. It has a function of emitting a signal, and the command signal in the rotation direction is approximated by setting the upper left of the display screen as the rotation center and replacing the rotation operation with a set of horizontal and vertical movements of each dot forming a reference pattern. It is given in the form of a constant that is obtained when moving the dot in the horizontal direction, and the contents of the constant are the number of vertical dots α required to move one dot in the horizontal direction, and the number α of dots required in the vertical direction to move one dot in the vertical direction. the number β of dots in the horizontal direction, and a command signal for parallel movement in the horizontal and vertical directions is given by the number X of dots moved in the horizontal direction and the number Y of dots moved in the vertical direction; In response to the command signal of the arithmetic processing means B, a horizontal rotation signal generating means C repeatedly outputs a signal every time α horizontal synchronizing signals are counted, and every time β horizontal dot clocks are counted. Vertical rotation signal generation means C' that repeatedly outputs a signal, and the number of horizontal movement dots commanded by the arithmetic processing means B each time a signal is output from the horizontal rotation signal generation means C. A vertical movement dot commanded by the arithmetic processing means B each time a signal is output from the horizontal translation signal generation means D for counting up or down X, and the vertical rotation signal generation means C'. A vertical parallel movement signal generating means D' that counts up or counts down the number Y, and a horizontal parallel movement command signal outputted from the horizontal direction parallel movement signal generating means D that counts up or counts down are used as a reference pattern. an addition means E which supplies the added horizontal address to the reference pattern storage means A, and a vertical direction count-up or count-down output from the vertical parallel movement signal generation means D'. adding means E' for adding a parallel movement command signal to the vertical address of the reference pattern and supplying the added vertical address to the reference pattern storage means A; The method is characterized in that the reference pattern is moved so as to overlap with the subject pattern.

[Effect]

The operation of the pattern moving device will be explained based on the block diagram of FIG.

The arithmetic processing means B compares and calculates a pre-stored reference pattern and a temporarily stored object pattern by specifying an address using a known method, and generates a command signal for correcting rotational deviation of the reference pattern with respect to the object pattern, and a horizontal and a command signal to correct the deviation in the vertical direction, and supplies the command signal to correct the rotational deviation to the rotation signal generation means C, C', and also moves the command signal to correct the deviation in the horizontal and vertical directions in parallel. The signal is supplied to signal generating means D and D'.

The content of the command signal for correcting rotational deviation is given by the number α of dots in the vertical direction required to move one dot in the horizontal direction and the number β of dots in the horizontal direction required to move one dot in the vertical direction. , α are supplied to horizontal rotation signal generation means C, and β is supplied to vertical rotation signal generation means C'.

Further, the horizontal and vertical deviations are given in the form of the number of dots moving in the horizontal direction X and the number Y of moving dots in the vertical direction, and the number of moving dots in the horizontal direction The number Y of moving dots is supplied to vertical translation signal generating means D'.

The outputs from the rotation signal generation means C and C' are also supplied to the parallel movement signal generation means D and D', respectively, and each time a signal is output from the rotation signal generation means C and C', a horizontally moving dot is generated. Count up the increase in dots due to rotational movement or count down the decrease in dots to the number The total number of moving dots is calculated and supplied to the subsequent adding means E and E', respectively.

The process of calculating the amount of horizontal and vertical movement to correct the rotational deviation, the rotational movement operation of the pattern based on this calculation result, the process of calculating the amount of horizontal and vertical movement necessary to correct the original horizontal and vertical deviation, and The rotational movement operation of the pattern based on this calculation result will be explained separately as follows. Here, the parallel movement operation for correcting the horizontal and vertical deviations will be described, and then the operation for correcting the rotational deviation will be described, but these processes are actually performed simultaneously.

First, to perform parallel translation in the horizontal or vertical direction in order to correct horizontal and vertical deviations, do the following. That is, the horizontal movement dot number X, which is a horizontal movement command signal supplied from the arithmetic processing means B, is sent to the addition means E via the parallel movement signal generation means D.
The addition means E adds the number X of horizontally moved dots to the original horizontal address of each dot constituting the pattern, and supplies the added horizontal address to the reference pattern storage means A. On the other hand, similar processing is performed in the vertical direction, and the number Y of vertically moving dots, which is a vertically moving command signal, is input to the parallel moving signal generating means D'.

If the rotational deviation is not corrected, the horizontal and vertical movement command signals input to the parallel movement signal generation means D and D' are supplied as they are to the addition means E and E', and the addition means E and E' The signal to be translated in the vertical direction is added to the original vertical address, and the added horizontal and vertical addresses are stored in the reference pattern storage means A.
supply to. By doing this, the contents stored in the address of the reference pattern storage means A are transferred together with the address.

In addition, in order to rotate, the horizontal synchronization signal used for screen creation is
A command signal to count the dot clocks is given to the rotation signal generating means C, and in the same way, a command signal to count β horizontal dot clocks used for screen creation is given to the rotation signal generating means C for one bit advance or delay in the vertical direction. A command signal is given to the rotation signal generating means C'.

The rotation signal generating means C and C' count horizontal synchronization signals and horizontal dot clocks respectively based on the commands, and each time α horizontal synchronization signals are counted or β horizontal dot clocks are counted, parallel movement of the next stage is started. A signal is issued to the signal generating means D, D' respectively, and each time the parallel movement signal generating means D, D' receives this signal, the horizontal and vertical movement command signals are supplied from the arithmetic processing means B. The number X of horizontally moving dots and the number Y of vertically moving dots are counted up or down depending on the direction of rotation. Then, the summed horizontal and vertical translation signals obtained by counting up or down are added to the original horizontal and vertical addresses of each dot constituting the pattern by means of addition means E and E'. By supplying the added address to the reference pattern storage means and moving the address of the reference pattern, the binary signal within the address is substantially moved.

After the pattern has been moved as described above, pattern inspection is performed by simply performing a logical operation on the signals of the moved reference pattern and the object pattern.

〔Example〕

The details of the pattern moving device according to the present invention will be explained based on the illustrated embodiment.

FIG. 9 shows an overall block diagram of the pattern moving device, and FIG. 10 shows a block diagram showing the part that moves addresses.

In the figure, 1 is a binarization circuit, the video camera is an IC,
A video signal that captures the shape and pattern of a printed circuit board, etc., and the markings on the surface of an IC package is converted into a binary signal via an amplifier, etc., and this binary conversion circuit 1 converts the
The converted signal is restricted within the window created by the window circuit 2 and displayed on the CRT. As is well known, this window is created by the screen address creation circuit 3, which divides the horizontal dot clock, which is the reference for image creation, to create horizontal and vertical address signals that set each position on the screen. and forms a window that determines the outer periphery of the scanned image.

With the above circuit, the pattern, shape, etc. of the reference product is imaged in advance with a video camera, a binary signal of the reference pattern is created, and this data is temporarily stored in the temporary storage circuit 4. The temporary storage circuit 4 is an integrated circuit, and inputs the binary signal limited within the window (hereinafter simply referred to as the binary signal) and the address signal created by the screen address creation circuit 3, and receives the specified signal. The binary signal is temporarily stored at the address, and the memory becomes empty after the binary signal is transferred to the reference pattern storage means to be described later. Next, the subject pattern is temporarily stored in this empty temporary storage circuit 4.

Reference pattern storage means A and A' are integrated circuits, which are connected to the temporary storage circuit 4 through gate circuits 5, 6, and 7, and store the contents stored in the temporary storage circuit 4. It is for. In order to transfer the memory contents of the temporary storage circuit 4 to the reference pattern storage means A, the binary signal in the temporary storage circuit 4 is passed through when the gate circuit 5 is opened by a command signal from the arithmetic processing means to be described later. let me,
The gate circuit 6 connected to the input terminal of the reference pattern storage means A is opened by a command signal from the CPU and outputs a signal obtained by appropriately reducing the binary signal by several bits. The value signal is stored and used as a reference pattern (1). To store a reference pattern in the other reference pattern storage means A', the gate circuit 7 stores a reference pattern obtained by appropriately enlarging the binary signal by several bits, and sets this as a reference pattern (2). The storage means A, A' are storage elements made of integrated circuits, but a floppy disk or data tape may be used to increase the storage capacity.

B is an arithmetic processing means, which includes the gate circuit 5,
At the same time, commands are given to open and close 6 and 7, and the reference patterns (1) and 7 are compared with the temporarily stored subject pattern to calculate the deviations in the horizontal, vertical and rotational directions, and the monitor program calculates the deviations in the horizontal, vertical and rotational directions. Call a constant that moves in each direction according to the shift, and put this constant on the data bus line. The constants mentioned here include constants necessary to correct horizontal and vertical deviations, constants necessary to correct rotational deviations, and constants necessary to correct horizontal and vertical deviations. Specifically, they are a command signal for parallel translation by X bits in the vertical direction, and a command signal for parallel translation by Y bits in the vertical direction, and the constants necessary to correct rotational deviation are shown in Figure 11 A and B. As shown in FIG. 1, the contents include a command to count α horizontal synchronizing signals for each bit advance in the horizontal direction, and a command to count β horizontal dot clock signals for each one bit advance in the vertical direction. In addition, the meaning of advance and delay here is that movement in the clockwise direction with the upper left of the display screen as the center of rotation is progress.
Movement in the opposite direction is considered a delay.

C is a rotation signal generating means for the horizontal direction;
The output of the latch circuit 8 and the output of the synchronous counter 9 are connected to the input terminal of the comparator 10, and the output terminal of the comparator 10 is fed back and connected to the reset terminal of the synchronous counter 9, and is also connected to the up-down counter 11 of the next stage. has been done. The rotation signal generating means C continues to output the counting command signal (counting α horizontal synchronizing signals) supplied from the arithmetic processing means B until the latch circuit 8 completes one image, and the latch circuit 8 When the command signal α and the number of horizontal synchronization signals counted by the synchronization counter 9 match, the comparator 10 outputs one pulse, this output pulse is returned to the reset terminal of the synchronization counter 9, and the same operation as above is repeated. The comparator 10 repeatedly outputs pulses until one image is completed.

Reference numeral D denotes horizontal translation signal generation means, in which the output of the comparator 10 is connected to the clock input terminal of the up-down counter 11, and the output terminal of the latch circuit 12 is connected to the up-down counter 1.
The latch circuit 12 continues to output a command signal to move in the horizontal direction (X dot movement command) supplied from the arithmetic processing means B, and the command signal of this latch circuit 12 Using this as a base value, every time a pulse is output from the comparator 10, the command signal (X dot movement command) is counted up or down as the base value to create a movement signal in the horizontal direction, and this movement signal is added. Supply means E.

The addition means E uses a so-called adder made of an integrated circuit, and uses horizontal address signals (H0, H1, H2...
), and the output signal of the up-down counter 11, that is, the signal that moves the whole in parallel by X dots, is horizontally shifted by 1 dot for every α horizontal synchronization signals (X+1, X+2, X+3...), and the horizontal It adds a horizontally moving signal (X+1, X+2, X+3,...) to the address signal (H0, H1, H2...), and the horizontal address signal (H0, H1+
X+2,...) as the reference pattern storage means A,
A′ is an address. What is shown in FIG. 11 is a case where it is assumed that there is no horizontal displacement (X=0) to simplify the explanation.

What has been described above relates to movement in the horizontal direction, but movement in the vertical direction is performed using rotation signal generation means C', parallel movement signal generation means D', and addition in the same way as for horizontal movement. using means E′,
Create a signal (Y+1, Y+2, Y+3, . . .) that moves the entire dot in parallel Y dots vertically by one dot every time β horizontal dot clocks are counted, and input this signal to the addition means E'. Add the signal to be vertically moved (Y+1, Y+2, Y+3,...) to the vertical address (V0, V1, V2, V...), and add the vertical address signal (V0, VI+
Y+1, V2+Y+2, . . . ) are supplied to the reference pattern storage means A, A' to be used as the new address of the reference pattern.

The reference pattern storage means A stores the reference pattern (1) which is a reduced pattern as described above, while the reference pattern storage means A' stores the reference pattern (2) which is an enlarged pattern. The reason why both the (reduced) reference pattern (1) and (enlarged) reference pattern (2) are created in this embodiment is as follows.

The final purpose of the pattern moving device of the present invention is to superimpose the moved reference pattern on the object pattern to judge whether the object is good or bad. It goes without saying that a product with a test pattern that completely matches the test pattern is a good product, but even if it does not match completely, as long as the error is within an acceptable range, the product must be judged as a good product. be. In other words, there is some variation in shape even in a non-defective workpiece, and this variation in shape must be tolerated. Of these, only the chipped portions that cut into the inside of the two-dot chain line pattern shown inside the solid line pattern are subject to defect detection.As for stains, protruding stains existing on the solid line pattern as shown in Fig. 13 are subject to defect detection. Of these, only the portion that protrudes outside the two-dot chain line pattern that exists outside the solid line pattern is subject to defect detection. In order to provide such a certain tolerance range, this embodiment provides a (reduced) reference pattern (1) and an (enlarged) reference pattern (2), as shown in FIG.

The (reduced) reference pattern (1) and the (enlarged) reference pattern (2) are created by moving the address using the method described above, thereby effectively moving the memory contents within the address, and superimposing it on the subject pattern to detect defects. However, for example, when detecting defects, Fig. 9,
As shown in FIG. 15, this is performed by inputting the inverted pattern of the reference pattern (1) inverted by the inverter 13 and the subject pattern to the AND gate 14. At this time, when a pulse signal is output from the AND gate 14, It is determined that there is a defect in the subject pattern, and when detecting dirt, the 9th
As shown in FIG. 16, the reference pattern (2) and the inverted pattern of the object pattern inverted by the inverter 15 are logically operated by the AND gate 16,
As a result, when a pulse signal is output, it is determined that there is dirt on the object pattern. The results of this logical operation are electrically processed signal processing and are extremely accurate. Therefore, for things such as semiconductor markings that require human visual perception to be judged, they are passed through the filter 17 to some extent. It has a wide range. The number of defective products can be determined by counting the signals passed through the filter 17 by the counter 18. In addition, the output amplifier 19
is connected to the video signal, the binary signal, the temporary storage signal, the reference patterns (1) and (2), and the output signal of the filter 17, and selects these signals and supplies them to the CRT 20.

As described above, since the moving means composed of semiconductor elements processes the command signal from the arithmetic processing means B using only electric signals, the processing speed is faster than when it is composed of software. In addition to being able to perform large-volume and high-speed inspection of patterns such as stamps, defective images and stains can be detected and judged by comparing the reduced reference pattern (1) and the enlarged reference pattern (2) with the subject pattern. It becomes possible.

〔Effect of the invention〕

The pattern moving device according to the present invention processes a command to superimpose a reference pattern on a subject pattern issued from an arithmetic processing means using a signal flow, so it uses a conventional method of mechanically moving a subject using a servo mechanism, or , it becomes possible to process faster than a method in which patterns developed in memory are compared point-by-point by program software over all dots. Furthermore, since the apparatus of the present invention compares the shapes of patterns by accurately superimposing the patterns, the inspection accuracy is far superior to that of defective product detection apparatuses that use area comparison, which has been widely used in the past.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing a reference pattern and an object pattern having a defective part, Fig. 2 is an explanatory drawing showing an object pattern that is misaligned with the reference pattern, and Fig. 3 A shows the rotational movement direction of the pattern. Explanatory diagram,
Figure 3B is an explanatory diagram showing the direction of parallel movement of the pattern, Figures 4A, B, C and 5 are explanatory diagrams showing the concept of pattern movement in the present invention, and Figure 6 is a synchronization signal for screen creation. FIG. 7 is an explanatory diagram showing the relationship between the display screen, the horizontal synchronizing signal and the horizontal dot clock, FIG. 8 is a block diagram of the pattern moving device according to the present invention, and FIGS.
The figure is a block diagram showing an embodiment of the pattern moving device according to the present invention, FIGS. 11A and 11B are explanatory diagrams of rotational movement, FIG. An explanatory diagram showing the meaning of creating an enlarged reference pattern, Fig. 14 is an explanatory diagram showing how a reduced reference pattern and an enlarged reference pattern are created based on the reference pattern, and Fig. 15 is an explanatory diagram showing the defect inspection method. , FIG. 16 is an explanatory diagram showing a method of soil inspection. A, A'...Reference pattern storage means, B...Arithmetic processing means, C, C'...Rotation signal generation means, D,
D'...Horizontal movement means, E, E'...Addition means,
1... Binarization circuit, 3... Screen address creation circuit, 4... Temporary storage circuit, 8... Latch circuit, 9
... Comparator, 10 ... Synchronous counter, 11
...Up-down counter, 12...Latch circuit.

Claims (1)

[Scope of Claims] 1. A reference pattern storage means A that stores a reference pattern in advance, and a comparison between the reference pattern stored in the reference pattern storage means A and the subject pattern, and rotation of the reference pattern with respect to the subject pattern. It has a function of emitting a command to move the reference pattern in the rotational direction to superimpose it on the subject pattern and a signal to command parallel movement in the horizontal and vertical directions, depending on the deviation in the horizontal and vertical directions. , the command signal in the rotational direction is obtained by approximating the upper left of the display screen as the center of rotation and replacing the rotational movement with a set of horizontal and vertical movements of each dot forming a reference pattern. It is given in the form of a constant, and the contents of the constant are the number of vertical dots α required to move one dot in the horizontal direction, and the number β of horizontal dots required to move one dot in the vertical direction. On the other hand, a command signal for parallel movement in the horizontal direction and vertical direction is given by the number of dots to be moved in the horizontal direction, X, and the number of dots to be moved in the vertical direction, Y. In accordance with the signal, a horizontal rotation signal generating means C repeatedly outputs a signal every time α horizontal synchronization signals are counted, and a vertical rotation signal generating means C repeatedly outputs a signal every time β horizontal dot clocks are counted. counting up or down the number of horizontally moving dots X commanded by the arithmetic processing means B each time a signal is output from the horizontal direction rotation signal generation means C' and the horizontal direction rotation signal generation means C; Each time a signal is output from the horizontal translation signal generation means D and the vertical rotation signal generation means C', the number Y of vertical movement dots commanded by the arithmetic processing means B is counted up or down. adding the count-up or count-down horizontal parallel movement command signal output from the vertical parallel movement signal generating means D′ and the horizontal direction parallel movement signal generating means D to the horizontal address of the reference pattern; Adding means E supplies this added horizontal address to the reference pattern storage means A, and a parallel movement command signal in the vertical direction which is counted up or down is outputted from the vertical direction parallel movement signal generating means D'. an addition means E' that adds to the vertical address of the reference pattern and supplies the added vertical address to the reference pattern storage means A; 1. A pattern moving device that moves a reference pattern as desired.