JPH0548573B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a magnification of a sample image for displaying the magnification of the sample image on the display screen of a scanning electron microscope or other electron beam apparatus (hereinafter referred to as SEM). This invention relates to display devices.

[Conventional Background] SEM irradiates and scans a sample with an electron beam, and displays an enlarged image of the sample on a sample image display device (eg, CRT) based on a sample signal generated during irradiation. Therefore, in SEM,
It is necessary to know how long the enlarged sample image corresponds to on the actual sample. For this reason, various devices have been proposed for SEM that display the scale of the sample along with the sample image on a display device.

[Conventional technology]

Conventionally, in a SEM, there are technical means for displaying the length on a sample according to the magnification together with the sample image, as shown in FIGS. 6 and 7, for example.

In the method shown in Fig. 6, scale 1 corresponding to a certain length (for example, 1 μm) on the sample is displayed together with sample image 2, and scale 1 is displayed on the display device according to the magnification of sample image 2. It is designed to expand and contract on the display screen 10 (Special Publication No. 47-21345)
issue).

However, according to such means, the sample image 2
As the magnification increases, the length of the scale 1 increases, and the scale 1 may protrude from the display screen 10.If the magnification is low, the length of the scale 1 decreases, and eventually, There is a problem in that the size of the sample cannot be determined accurately.

FIG. 7 shows a means for solving this problem. This displays on the display screen 10 a scale 4 with a constant length that is unrelated to the magnification of the sample image, and also displays the converted length of this scale 4 on the sample as a character (Tokuko Showa). 58-51664). According to such means,
Problems such as the scale 4 protruding from the display screen 10 or the scale 4 being too small and lacking in visibility are resolved.

However, in the case of such a method, when trying to find out the sample image length that is shorter than the set length of the scale 4, first, the length on the sample image 2 to be determined is a fraction of the length of the scale 4. The length on the sample image 2 must be found by determining whether the length on the sample image 2 corresponds to It takes time and effort to measure whether it corresponds to 1, and there is a problem in that it is not always possible to obtain an accurate value by eye.

[Means for solving problems]

The present invention has been made in view of the problems of the prior art described above, and aims to provide a sample image magnification display device that can accurately and easily measure a sample image. The means includes a reference line display means for displaying a reference line of a display scale on a display screen that displays a sample image, a reference scale display means for displaying a scale on the reference line, and a length of each of the reference line and reference scale. a reference line length for adjusting the length of the reference line under a predetermined magnification of the sample image; and a reference scale width adjustment means for adjusting the one scale width displayed by the reference scale display means on the reference line or an extension of the reference line independently of the length of the reference line. This is what I did.

〔Example〕

Embodiments of the present invention will be described below based on the accompanying drawings.

As shown in FIG. 2, the present invention provides a reference line 20 whose length can be changed on a display screen 10 displaying a sample image 15, and a reference line 20 on the sample image 15 to which the reference line 20 corresponds. The length (50μ) is displayed as a character, and in this embodiment, scale lines M0, M1, M2 are displayed on the reference line 20, and the magnification (×2000) of the sample image 15 and the scale lines are displayed. The scale width between M0 and M1 also displays the equivalent length (20μ) on the sample.

By the way, in the magnification display device of the present invention,
The scale width between the reference line 20 and the displayed scale lines M1 and M2 can be changed as appropriate. This will be explained based on FIG. In the various display examples in Fig. 1, the magnification is 5 times, and the symbol l in the figure is the scale line M.
It shows a scale width between 0 and M1.

First, a case will be described in which the reference line 20 and the scale width l are changed proportionally. As shown in Figure 1a,
When the converted length of the reference line 20 is displayed as 20 mm, and the converted length of the scale width l is displayed as 10 mm, if the displayed length of the reference line 20 is set to 1/2, as shown in Figure 1 b. As the length of the reference line 20 increases, the scale width l also becomes 1/2.
The converted length of the reference line 20 is 10 mm, and the scale width is l.
The character display also changes to 1/2 accordingly, such that the converted length is 5 mm.

Next, a case will be described in which the reference line 20 is changed irrespective of the scale width l. If the length of the reference line 20 is shortened when it is displayed as shown in Figure 1a, the character display of the reference line 20 and its converted length will be changed as shown in Figure 1c. Ru. However, the character display of the scale width l and its converted length remains unchanged. Next, when the length of the reference line 20 is further shortened from the display state shown in FIG. 1c, the scale line M1 is displayed on the extension line of the reference line 20, as shown in FIG. For example, the converted length of 20 and the converted length of scale width l are 5, respectively.
It is displayed as mm, 10mm, etc. On the other hand, if only the scale width l is changed from the display state of Fig. 1a, the length of the reference line 20 remains unchanged as shown in Fig. 1e, and the scale width l and its converted length are changed. The character display will change.

Next, a sample image magnification display device according to an embodiment of the present invention will be described.

As shown in FIG. 3, this device consists of a horizontal deflection coil 40 provided in the electron microscope main body (not shown).
By switching the current supplied to the vertical deflection coil 41 using the magnification switching devices 42 and 43, the sample image 15 is enlarged and displayed on the display screen 10 of the CRT 45, and the reference line display means 5
0, a scale line display means 60, and a character display means 70 to display necessary information regarding the length on the sample.

In this figure, 51 is a horizontal scanning circuit that outputs a sawtooth signal Ex, and 53 is a reference voltage source that applies reference voltages E0 and E2 for positioning the start and end points of the reference line 20 to the comparison circuit 52. The reference voltage source 53 is set based on the reference voltage E0, but the voltage value of the reference voltage E2 can be changed by the voltage regulator 59. Then, the comparator circuit 52 detects t ₁ , t 2 , when the reference voltage E0 and the reference voltage E2 set by the voltage regulator 59 match the sawtooth wave signal Ex, as shown in FIGS. 4a and _4b .
...outputs a signal at t ₁₂ . Further, 55 is a vertical scanning circuit that supplies a sawtooth wave signal Ey, and 57
is a reference voltage source that inputs reference voltages V1 and V2 to the comparison circuit 56 for determining the thickness of the reference line 20 and the height position of the display on the display screen 10. As shown in FIGS. 4c and 4d, this comparison circuit 56 outputs a pulse signal that becomes H level between ta and tb when the reference voltages V1 and V2 match the sawtooth wave signal Ey. The gate circuit 54 includes comparison circuits 52 and 56.
When the signals match, a signal as shown in FIG. 4e is output to the synthesizer 44. Due to this
A reference line 20 of an appropriate length is displayed on the display screen 10 of the CRT 45 at an appropriate position. Voltage regulator 5
If the voltage value of the reference voltage E2 changes by the operation 9, the length of the reference line 20 also changes. 6
1 is a comparison circuit 62 which compares reference voltages E0 and E1 having different voltage values corresponding to reference scales M0 and M1, respectively.
This is the scale reference voltage source applied to the scale. This reference voltage source 61 is based on the reference voltage E0, but the reference voltage E1 is changed to an appropriate voltage value by a voltage regulator 69. Note that the two voltage regulators 59 and 69 are connected to each other by a switching device (not shown).
They can be switched to operate independently or in conjunction. Also voltage regulators 59, 69
may be linked with a magnification switching device by a switch Q.

The comparison circuit 62 includes a horizontal scanning circuit 51
The sawtooth wave signal Ex is input from the fifth
As shown in FIGS. a and b, when the reference voltages E0 and E1 match the sawtooth wave signal Ex, the pulse generation circuit 65 outputs signals on the reference scales M0 and M1. Further, a reference voltage E2 corresponding to the reference scale M2 to be displayed on the right end of the reference line 20 is inputted to the comparison circuit 62 from an independent reference voltage source 64.
Therefore, the comparison circuit 62 outputs a signal on the reference scale M2 when the reference voltage E2 and the sawtooth wave signal Ex match, as shown in FIGS. 5c and 5d.

On the other hand, 67 is a reference voltage source that applies reference voltages V1 and V3 that determine the scale height of the reference scale M to the comparison circuit 66. The sawtooth wave signal Ey from the vertical scanning circuit 55 is input to the comparator circuit 66, and as shown in FIG.
When Ey and reference voltages V1 and V3 match, ta~
Generates a signal between tc. Therefore, the gate circuit 63
generates a signal as shown in FIG. 5g when the signals from the comparison circuits 62 and 66 match. As a result, there is a reference scale M1 on the reference line 20 that moves appropriately from left to right on the reference line 20 by operating the voltage regulator 69, and a reference scale M1 that is set as the starting point and end point of the reference line.
0 and M2 are displayed. 71 is a magnification display circuit;
2 is a reference line length display circuit, and 73 is a scale width display circuit. These circuits 72 and 73 calculate numbers to be displayed as information using arithmetic circuits 75 and 76 such as microcomputers, and input the calculation results to the synthesizer 44 as information signals. Incidentally, each display circuit 71, 72, 73 is connected to a vertical scanning circuit 5 in order to determine the character display position.
The sawtooth wave signal Ey is taken from 5 and displayed as a character at a position that matches a preset reference voltage.

As described above, each signal inputted to the synthesizer 44 from the gate circuits 54, 63 and each display circuit 71, 72, 73 is transmitted to the CRT as a luminance modulation signal.
The reference line 20, the scale line M, and the character are displayed on the display screen 10. It goes without saying that the horizontal deflection coil 40 and vertical deflection coil 41 of the SEM body and the horizontal deflection coil 47 and vertical deflection coil 48 of the CRT 45 are synchronized by signals from the scanning circuits 51 and 55.

Further, reference line display means 50, scale line display means 6
0 can also be configured using a microcomputer and digital processing can be performed.

〔Effect of the invention〕

As explained above, the present invention includes a reference line length adjusting means for adjusting the length of the reference line under a predetermined magnification of a sample image, and a reference scale means on the reference line or an extension of the reference line. and a reference scale width adjustment means for adjusting the width of one scale displayed on the screen independently of the length of the reference line. Therefore, according to the present invention, the length of the reference line can be changed as appropriate,
In addition, the width of one division of the reference scale can also be changed as appropriate, and the length of the changed reference line and reference scale can be known by using the converted length displayed in the character. Accurate measurements of images can be made. As a result, even when there are a plurality of sample images on the display screen, it is possible to know how large the sample is compared to other samples.

[Brief explanation of the drawing]

FIG. 1 is a partially enlarged view of FIG. 2 showing magnification display on the display screen, FIG. 2 is a diagram showing a method for displaying magnification of a sample image according to an embodiment of the present invention, and FIG. 3 is an embodiment of the present invention. Block diagram illustrating a magnification display device according to the fourth embodiment.
5 and 5 are time charts showing the operation of the magnification display device according to the embodiment of the present invention, and FIGS. 6 and 7 are diagrams showing a conventional magnification display method. 10...Display screen, 20...Reference line, 50...
Reference line display means, 60... Scale line display means, 70
...Character display means.

Claims (1)

[Scope of Claims] 1. Reference line display means for displaying a reference line of a display scale on a display screen that displays a sample image, reference scale display means for displaying a scale on the reference line, and the reference line and reference scale. A scale scale display device for a sample image, comprising character display means for characterizing the converted length of the sample image to which each length corresponds, the length of the reference line being adjusted under a predetermined magnification of the sample image. a reference line length adjusting means for adjusting the reference line length, and a reference scale width adjusting means for adjusting one scale width displayed by the reference scale display means on the reference line or an extension of the reference line independently of the length of the reference line. A scale scale display device for a sample image, characterized by comprising: