JPH0968968A - Image display device - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide an image display device capable of easily observing a line profile in real time. [Structure] Inputted two-dimensional image data is converted into a digital signal by an A / D converter 2 and stored in an image memory 4. The line profile calculation unit 6 extracts data of a predetermined horizontal line from the image data converted into the digital signal in synchronization with scanning of each horizontal line, and calculates one-dimensional line profile data. The line profile display unit 7 stores the one-dimensional line profile data calculated by the line profile calculation unit 6 in the one-dimensional line memory 15, and based on the stored one-dimensional data, the line profile data is stored in the line profile data. The dots at the corresponding positions and the positions at which the respective line profile data are to be interpolated are displayed on the display 12 in real time as a two-dimensional line profile.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device,
In particular, the present invention relates to an image display device suitable for displaying a line profile such as image data captured by a device such as a scanning electron microscope, a transmission electron microscope, or an electron beam drawing device.

[0002]

2. Description of the Related Art Scanning electron microscopes, transmission electron microscopes,
Image data taken by a device such as an electron beam drawing device is CR
Although it is displayed on an image display device having a display device such as T, it is known to display a line profile for observing the sample shape and adjusting the focus. The line profile displays data of a specific one horizontal line or a plurality of horizontal lines in one frame of image data. There are two ways to display this line profile.
In addition to the method of using a one-dimensional bitmap, there is a method of displaying in real time using a one-dimensional line memory.
As a method of using a bit map, for example, Japanese Patent Laid-Open No. Hei 2
The ones described in JP-A-51068 and JP-A-3-59466 are known.

A method of displaying in real time is, for example,
This is an effective method for focus adjustment and the like, because the data that changes every 16 ms is sequentially displayed.

When the line profile data stored in the conventional line memory is displayed in real time, one horizontal address corresponds to the line memory value.
Only the dots were displayed.

[0005]

However, in the conventional method of displaying only one dot corresponding to the line memory value for one horizontal address, the display dot is changed in the case of a rapidly changing data value. The distance may be greatly separated. Since the amount of secondary electrons detected by a scanning electron microscope or the like may change from moment to moment, 16
In real-time display for each ms, the position of one dot that is displayed also changes. Therefore, when observing on the display, the position of the bright spot also changes, and the flicker causes a problem that it is difficult to observe the characteristics of the line profile. there were.
Therefore, when observing the line profile for observing the sample shape or adjusting the focus with a scanning electron microscope, a transmission electron microscope, an electron beam drawing apparatus, or the like, there is a problem that it is difficult to observe the characteristics.

An object of the present invention is to provide an image display device which allows easy real-time line profile observation.

[0007]

In order to achieve the above object, the present invention provides an A / D converter for converting input two-dimensional image data into a digital signal and a digital signal by the A / D converter. In the image display device having a storage unit for storing the two-dimensional image data converted into the image data and a display unit for displaying the image data stored in the storage unit, among the image data converted into the digital signal, A line profile calculating means for calculating data of a predetermined horizontal line by synchronizing with scanning of each horizontal line to calculate one-dimensional line profile data; and one-dimensional line profile data calculated by the line profile calculating means. This line profile is stored in a one-dimensional line memory and based on the stored one-dimensional data. The position of the dot position and interpolating each line profile data corresponding to Rudeta as a two-dimensional line profile is obtained so as to include a line profile displaying means for displaying in real time on the display means.

In the above image display device, preferably
The line profile display means linearly interpolates between the respective line profile data.

In the above image display device, preferably
The line profile display means stores a one-dimensional line memory for storing the line profile data calculated by the line profile calculation means, and the line profile data stored in the line memory for each horizontal address of the line memory. And a comparing means for comparing the vertical address.

In the above image display device, preferably
The comparing means includes a first comparing means for comparing line profile data and a vertical address with respect to a predetermined horizontal address, and a second comparing means for comparing line profile data and a vertical address with respect to a horizontal address preceding the predetermined horizontal address by one. The comparison means and the gate means for obtaining the logical product of the first and second comparison means are configured.

In the above image display device, preferably
The line profile display means includes a one-dimensional line memory that stores the line profile data calculated by the line profile calculation means, and a vertical converter that converts the line profile data stored in the line memory into a vertical address of the display means. Address conversion means, first comparing means for comparing the vertical address conversion value of the line profile data converted by the vertical address conversion means with a vertical address, and the line profile data converted by the vertical address conversion means. A second vertical address conversion value holding means for holding the vertical address conversion value for one horizontal address period, and a second comparison for comparing the vertical address conversion value of the line profile data held by the vertical address conversion value holding means with the vertical address. Means and Is obtained so as to constitute a gate means for obtaining a logical product of the outputs of said first and second comparing means.

In the above image display device, preferably
The line profile calculation means is adapted to calculate the line profile data from the image data stored in the storage means.

In the above image display device, preferably,
The line profile calculating means is adapted to calculate the line profile data from the image data converted into a digital signal by the A / D converter.

[0014]

According to the present invention, line profile calculation means for calculating one-dimensional line profile data by extracting data of a predetermined horizontal line from the image data converted into a digital signal in synchronization with scanning of each horizontal line. The one-dimensional line profile data calculated by the line profile calculating means is stored in the one-dimensional line memory, and the position and each line corresponding to the line profile data are stored based on the stored one-dimensional data. By providing a line profile display means for displaying dots at positions for interpolating profile data as a two-dimensional line profile on the display means in real time, it is possible to obtain a display of a line profile with little flicker.

Further, the line profile display means can be easily interpolated by linearly interpolating between the respective line profile data.

Further, the line profile display means stores a one-dimensional line memory for storing the line profile data calculated by the line profile calculation means, and the line memory for each horizontal address of the line memory. Further, by comprising the line profile data and the comparison means for comparing the vertical address, the interpolation can be performed with a simple structure.

Further, the comparing means compares the line profile data and the vertical address for a predetermined horizontal address with the first comparing means and the line profile data and the vertical address for a horizontal address one before the predetermined horizontal address. And a gate means for obtaining the logical product of the first and second comparison means, thereby interpolating both the data increasing in the horizontal address direction and the data decreasing in the horizontal address direction. It will be possible.

Further, the line profile display means has a one-dimensional line memory for storing the line profile data calculated by the line profile calculation means, and the line profile data stored in this line memory in the vertical direction of the display means. Vertical address conversion means for converting the address, first comparison means for comparing the vertical address conversion value of the line profile data converted by the vertical address conversion means with the vertical address, and the vertical address conversion means for converting the vertical address conversion value. Vertical address conversion value holding means for holding the vertical address conversion value of the line profile data for a period of one horizontal address,
Second comparison means for comparing the vertical address conversion value of the line profile data held in the vertical address conversion value holding means with the vertical address; and gate means for obtaining the logical product of the outputs of the first and second comparison means. With this configuration, the vertical address can be arbitrarily designated and the line profile can be displayed at any position on the screen of the display means.

The line profile calculation means can display the line profile of the image data subjected to the calculation processing by calculating the line profile data from the image data stored in the storage means.

Further, the line profile calculating means can directly display the line profile by calculating the line profile data from the image data converted into the digital signal by the A / D converter.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a block diagram of an image display device according to an embodiment of the present invention.

An image input signal 1 such as image data photographed by a device such as a scanning electron microscope, a transmission electron microscope or an electron beam drawing device is analog / digital converted by an A / D converter 2 to obtain a digital signal. Input to the calculation unit 3. The arithmetic unit 3 transfers the waveform-shaped digital signal to the display memory 5 and stores the waveform-shaped digital signal after performing a waveform shaping operation such as a filter.

In addition, the line profile calculation unit 6 includes
The image data analog-to-digital converted by the A / D converter 2 or the image data in the image memory 4 is fetched. The line profile calculation unit 6 calculates a line profile based on the captured image data,
The calculated line profile is stored in the line profile display unit 7. The line profile display unit 7 is provided with a line memory, and the data of the line profile is stored in this line memory, the details of which will be described later.

Bit map data 8 such as characters and figures are stored in the bit map memory 9.

The updating of the writing of data to the display memory 5, the line memory in the line profile display section 7, and the bit map memory 9 is performed in real time.

The three data of the display memory 5, the line memory in the line profile display section 7, and the bit map memory 9 are read out respectively, and the display overlay section 1 is read.
It is superposed with 0. Then, digital / analog conversion is performed by the D / A converter 11, and the result is displayed on the display 12 such as a CRT.

Reading of data from the display memory 5, the line memory in the line profile display unit 7, and the bit map memory 9 is performed in synchronization with the video clock VCLK. In the TV scanning of the display device 12, horizontal scanning is performed in synchronization with the horizontal synchronization signal HSYNC, and display of dots during horizontal scanning is performed in synchronization with the video clock VCLK.

Next, the display of the line profile according to the embodiment of the present invention will be described with reference to FIG. FIG.
FIG. 4 is a block configuration diagram of a line profile display unit according to an embodiment of the present invention.

The vertical address counter 13 receives the horizontal synchronizing signal HSYNC and the vertical synchronizing signal VSYNC, counts the horizontal synchronizing signal HSYNC of the TV scanning of the display 12, and resets with the vertical synchronizing signal VSYNC. , Vertical address m during TV scanning (position in the vertical direction of the horizontal scanning line) is output and input to the comparison unit 20.

The line memory 15 stores the line profile data output by the line profile calculating section 6. The horizontal synchronization signal HSYNC and the video clock signal VCLK are input to the line memory 15, the reading of data from the line memory 15 and the increment of the address are synchronized with the video clock signal VCLK, and the reset of the address is performed by the horizontal synchronization signal HSYNC. The line memory data value Ln is read out as described above. The line memory 15 has the address of the display 12
It is configured so as to match the horizontal address of the TV scan (the horizontal position of the dot being scanned). The capacity of the line memory 15 is horizontal 640 × 8 bits.

The line memory data value Ln read from the line memory 15 is input to the line memory data value / vertical address conversion unit 16. Line memory data value /
The vertical address conversion unit 16 converts the input line memory data value Ln into the vertical address Dn of the display device 12. As described above, the capacity of the line memory 15 is 640 × 8 bits (= 640 × 256) in the horizontal direction, whereas the display area of the display unit 12 is 640 × vertical in 480, so that the display in the vertical direction is performed. Since the area is larger than the number of data bits, conversion is performed to adjust both. Here, the line profile display is divided into the centers with the center of the vertical direction of the display area as the center.

The horizontal address (horizontal position of the dot being scanned) is n = 1 to 640, and the vertical address is m = 1 to 48.
0. However, the upper left of the display 12 is the origin for both addresses. In the above relationship, the relationship between the line memory data value Ln and the vertical address conversion value Dn is converted as follows.

Dn = (480/2) + (256/2) -Ln = 368-Ln The line memory data value / vertical address conversion unit 16 calculates the line memory data value Ln based on the above equation. Convert to address Dn. The vertical address Dn converted by the line memory data value / vertical address conversion unit 16 is output to the comparison unit 20 and the flip-flop 17.

The flip-flop 17 is the T of the display 12.
This is for obtaining the vertical address conversion value D (n-1) of the line memory data value corresponding to the horizontal address H (n-1) that is "1" before the horizontal address Hn during V scanning. The flip-flop 28 has a 9-bit configuration and is synchronized with the video clock VCLK19. The vertical address conversion value D (n−1) is input to the comparison unit 20.

The comparing section 20 has four comparators 21, 22, 22.
23, 24, OR gates 25, 27, 29, and AND gates 26, 28. The comparison unit 20 includes a vertical address m and vertical address conversion values Dn and D.
Three types of signals (n-1) are input. Comparators 21, 2
Reference numeral 3 compares the vertical address m with the vertical address conversion value Dn and compares three types of comparison outputs m> Dn, m = Dn, m <Dn.
Is output. Further, the comparators 22 and 24 compare the vertical address m with the vertical address conversion value D (n-1), and three types of comparison outputs m> D (n-1), m = D (n-1). , M
<D (n-1) is output.

The OR gate 25 receives the comparison outputs m = Dn and m <Dn of the comparator 21, and outputs the logical sum of them. The AND gate 26 receives the output of the OR gate 24 and the comparison output m> D (n-1) of the comparator 22 as an input, calculates the logical product of them, and outputs them.

Further, the OR gate 27 receives the comparison output m> Dn, m = Dn of the comparator 23 as an input and takes the logical sum of them to output. The AND gate 28 receives the output of the OR gate 27 and the comparison output m <D (n-1) of the comparator 24 as an input, and outputs a logical product of them.

The OR gate 29 is connected to the outputs of the AND gates 26 and 28, and takes the logical sum of them to output them.

Since the comparator 20 is constructed as described above, the vertical address m24 during TV scanning of the display is
Between the vertical address conversion value Dn27 of the line memory data value corresponding to the horizontal address and the vertical address conversion value D (n-1) 29 of the line memory data value corresponding to the horizontal address preceding the horizontal address by one. It is determined whether it is a value, and if so, 1 is output.

The input of the comparator 20 is D (n-1) <m≤.
In the case of Dn or Dn ≦ m <D (n−1), 1 is output. Each of the comparators 21, 22, 23 and 24 has two 9-bit inputs A and B, and A <B and A =
It is configured to have three outputs that output 1 when either B or A> B.

With the above configuration, the vertical address during TV scanning of the display is the vertical address conversion value of the line memory data value corresponding to the horizontal address, and the line memory corresponding to the horizontal address one before the horizontal address. By displaying the dot when the value is between the vertical address conversion value of the data value, the line profile is displayed on the display unit and the dots of the data to be displayed on the display unit are linearly interpolated in real time. It becomes possible to do.

The address of the line memory is made to coincide with the horizontal address of the TV scanning of the display (the horizontal position of the dot being scanned).

Next, a display example of the line profile in the image display device according to the embodiment of the present invention will be described with reference to FIG. In addition, a display example of the line profile according to the conventional method will be described with reference to FIG. FIG. 3 is an explanatory diagram of a display example of a line profile in the image display device according to the embodiment of the present invention, and FIG. 4 is an explanatory diagram of a display example of the line profile according to the conventional method.

In FIG. 3, FIG. 3A shows the display area 30 of the display unit, and FIG. 3B shows the data area 32 of the line memory.

The data area 32 of the line memory 15 is horizontal 640 × 8 bits (= 640 × 256). Since the display area 30 of the display unit 12 is horizontal 640 × vertical 480, the display area in the vertical direction is larger than the number of data bits, so conversion is performed in order to adjust both. In this case, the line profile display is centered around the vertical middle point (m = 240) of the display area.

The horizontal address (horizontal position of the dot being scanned) is n = 1 to 640, and the vertical address is m = 1 to 48.
0. However, the upper left of the display 12 is the origin for both addresses.

As shown in FIG. 3B, the vertical address conversion value Dn-1 is stored in the horizontal address (n-1) of the data area 32 of the line memory.
It is assumed that the vertical address conversion value Dn is stored in. At this time, the display for the vertical address conversion value D is such that, for the vertical address conversion value Dn-1, two bright spots (dots) Gn-1 are displayed in the display area 30, and for the vertical address conversion value Dn. As a result, four bright spots (dots) Gn are displayed in the display area 30.

On the other hand, in the conventional art, as shown in FIG. 4, one bright spot (dot) Hn-1 is displayed in the display area 30 for the vertical address conversion value Dn-1, and the vertical address conversion value Dn-1 is displayed. For the value Dn, one bright spot (dot) Hn is displayed in the display area 30.

Next, as shown in FIG. 3, the operation of the comparator 20 shown in FIG. 2 for displaying bright spots will be described with reference to FIG.
This will be described with reference to FIG. FIG. 5 is an explanatory diagram of a display on the image display device according to the embodiment of the present invention.

FIG. 5A shows an example in which the display is made by the comparators 21 and 22 among the comparators 20 shown in FIG. Here, the vertical address conversion value Dn-1 = 246
Assuming that the vertical address conversion value Dn = 250, the vertical address m changes from 1 to 480, and particularly from m = 246 to 250 in FIG. 5A.

The output of m> Dn-1 of the comparator 22 is 24 when m is 24 because the vertical address conversion value Dn-1 is 246.
If it is greater than 6, the output is "1". Also,
The output of m = Dn of the comparator 21 is "1" when m is 250. Therefore, with respect to the horizontal address n, at the position where the vertical address m is 250,
A bright spot (dot) Gn (250) indicated by a black circle is displayed.

The output of the comparator 21 for m <Dn is m
Is less than 250, the output is "1". Therefore, for the horizontal address n, the AND of the output of the comparator 22 is taken by the AND gate 26, so that the vertical address m is from 247 to 249.
Bright spots (dots) indicated by white circles Gn (249), Gn (248), G
n (247) is displayed. Here, for the sake of explanation, a black circle and a white circle are distinguished, but both are displayed as the same bright point.

FIG. 5B shows an example of the case where the display is made by the comparators 23 and 24 among the comparators 20 shown in FIG. Here, the vertical address conversion value Dn-1 = 250
Assuming that the vertical address conversion value Dn = 246, the vertical address m changes from 1 to 480, and particularly from m = 246 to 250 in FIG. 5B.

Since the vertical address conversion value Dn-1 is 250, the output of the comparator 24 for m <Dn-1 is 25 for m.
If it is less than 0, the output is "1". Also,
The output of m = Dn of the comparator 23 is "1" when m is 246. Therefore, the vertical address m is 246 with respect to the horizontal address n,
A bright spot (dot) Gn (246) indicated by a black circle is displayed.

Further, the output of the comparator 23 when m> Dn is m
Is greater than 250, the output is "1". Therefore, for the horizontal address n, the AND of the output of the comparator 24 is taken by the AND gate 28, so that the vertical address m is at the position of 247 to 249.
Bright spots (dots) indicated by white circles Gn (247), Gn (248), G
n (249) is displayed. Here, for the sake of explanation, a black circle and a white circle are distinguished, but both are displayed as the same bright point.

As described above, when Dn is larger than Dn-1, a plurality of bright points are displayed for the horizontal address n according to the principle described with reference to FIG. Also, D
When Dn is smaller than n-1, a plurality of bright spots are displayed for the horizontal address n according to the principle described with reference to FIG.

In the conventional method of displaying one bright point at a horizontal address as shown in FIG. 4, this display is
Since it is a real-time display that sequentially displays the data stored in the line memory that is rewritten each time the display unit scans horizontal lines, when the data stored in the line memory changes, for example, bright points (dots) indicated by black circles Hx
Is moved up and displayed, and is indicated by a dashed circle H
x ', or a bright dot (dot) Hx indicated by a black circle,
It may be displayed downward, and may be Hx ″ indicated by a broken line circle. Such flicker makes it very difficult to observe the line profile.

On the other hand, as shown in FIG. 3, by displaying a plurality of bright spots at the same horizontal address, even if the data stored in the line memory changes, the bright spots to be displayed are changed. Since the position of is less changed than that shown in FIG. 4, it is possible to obtain the display of the line profile with less flicker.

In the above description, the line profile data Dn and Dn-1 are compared with the vertical address m, but the average value (Dn + Dn-1) / 2 of the line profile data Dn and the line profile data Dn-1. By providing two more comparators for comparing the average value (Dn + Dn-1) / 2 and the vertical address m, for example, in FIG. If the horizontal address (n-1) is displayed instead of the address n, curved interpolation is performed and the line profile can be displayed more faithfully.

[0061]

According to the present invention, it is possible to easily observe a line profile in real time on an image display device.

[0062]

[Brief description of drawings]

FIG. 1 is a block diagram of an image display device according to an embodiment of the present invention.

FIG. 2 is a block diagram of a line profile display unit of the image display device according to the embodiment of the present invention.

FIG. 3 is an explanatory diagram of a display example of a line profile of the image display device according to the embodiment of the present invention.

FIG. 4 is an explanatory diagram of a display example of a line profile according to a conventional method.

FIG. 5 is a principle explanatory diagram of a display example of a line profile in the image display device according to the embodiment of the present invention.

[Explanation of symbols]

 2 ... Analog / digital converter 3 ... Input image data calculation unit 4 ... Image memory 5 ... Display memory 6 ... Line profile calculation unit 7 ... Line profile display unit 9 ... Bit map memory 10 ... Display overlay unit 11 ... Digital / analog Converter 12 ... Display device 13 ... Vertical address counter 15 ... Line memory 16 ... Vertical address conversion unit of line memory data value 17 ... Flip-flop 20, 21, 22, 23, 24 ... Comparator 32 ... Line memory data configuration

Claims (7)

[Claims] 1. An A / D converter for converting input two-dimensional image data into a digital signal, and storage means for storing the two-dimensional image data converted into a digital signal by the A / D converter. In an image display device having a display means for displaying the image data stored in the storage means, data of a predetermined horizontal line in the image data converted into the digital signal is synchronized with scanning of each horizontal line. Line profile calculating means for extracting and extracting one-dimensional line profile data, and 1 calculated by this line profile calculating means
Dimensional line profile data is stored in a one-dimensional line memory, and based on the stored one-dimensional data, dots at positions corresponding to this line profile data and at positions for interpolating each line profile data are two-dimensional. An image display device, comprising: a line profile display unit for displaying the line profile as a line profile on the display unit in real time. 2. The image display device according to claim 1, wherein the line profile display means linearly interpolates between the respective line profile data. 3. The image display device according to claim 1, wherein the line profile display means stores a one-dimensional line memory for storing the line profile data calculated by the line profile calculation means, and each horizontal line memory of the line memory. An image display device comprising: a comparison means for comparing the vertical address with the line profile data stored in the line memory for each address. 4. The image display device according to claim 3, wherein the comparison means includes first comparison means for comparing line profile data and vertical address for a predetermined horizontal address, and one before the predetermined horizontal address. An image display device comprising: a second comparing means for comparing line profile data for a horizontal address with a vertical address; and a gate means for obtaining a logical product of the first and second comparing means. 5. The image display device according to claim 1, wherein the line profile display means stores a one-dimensional line memory for storing the line profile data calculated by the line profile calculation means, and the line memory is stored in the line memory. Vertical address conversion means for converting the line profile data into the vertical address of the display means, and first comparison means for comparing the vertical address conversion value of the line profile data converted by the vertical address conversion means with the vertical address. Vertical address conversion value holding means for holding the vertical address conversion value of the line profile data converted by the vertical address conversion means for one horizontal address period, and the line profile data held in the vertical address conversion value holding means Vertical An image display device comprising: a second comparison means for comparing a dress conversion value and a vertical address; and a gate means for obtaining a logical product of outputs of the first and second comparison means. 6. The image display device according to claim 4 or 5, wherein the line profile calculation means calculates the line profile data from the image data stored in the storage means. Image display device. 7. The image display device according to claim 4 or 5, wherein the line profile calculation means extracts the line profile data from the image data converted into a digital signal by the A / D converter. An image display device characterized by being calculated.