JPS59180306A - Noncontact optical type displacement measuring device with display mechanism for visual field state of measurement - Google Patents

Abstract

PURPOSE:To facilitate the confirmation of a visual field of measurement and correction to a measurable range and to measure displacement without any high- level skillfulness by expanding the visual field of measurement and judging the state in the visual field. CONSTITUTION:Variable voltage generation parts 23h and 23v apply variable voltages to deflecting coils 9 and 10 to expand the visual field of measurement by electric deflection. Arithmetic processors 20h and 20v receive a signal showing the target state in the visual field and a signal showing a preset measurement mode to make state judgements. Then, warning parts A1 and A2 generate warnings on the basis of the outputs of the devices 20h and 20v according to the displacement direction of a target or whether the set mode matches with the target or not. Therefore, whether the light part of the target is present in a set measurable direction or not and which center of the visual field of measurement the light/dark boundary of the target is present in are confirmed easily by the warnings, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a non-contact optical displacement measurement system that is equipped with a mechanism that displays whether or not the measurement field of view is correct when performing non-contact displacement measurement by optically capturing minute displacements. It is related to the device.

A non-contact optical displacement measuring device converts a bright and dark target image of a displaced part into an electronic image in an image dissector tube,
This is a device that measures the displacement of this electronic image. Since such a device can measure without contacting the displaced portion, it is possible to accurately measure high-speed displacement, minute displacement, etc. from a remote position without affecting the operating state. In other words, it is sufficient that the displaced portion can be captured optically.

Regardless of its properties, it is possible to measure displacement without interfering with the original operating state, so it is widely used in various fields such as research, testing, manufacturing, and inspection.

Many of these conventional non-contact optical displacement measuring devices use a display section such as a bidirectional n-meter to display the amount of displacement in an analog manner. In this case, since the measurable range is often narrower than the field of view in which the bright and dark targets are optically captured, there is a drawback that if the bright/dark boundary of the target deviates even slightly from the measurable range, it can no longer be displayed. To compensate for this drawback, a method has been adopted in which an oscilloscope is connected in parallel and the signal from the measuring device is checked on a CRT, but this method cannot be confirmed if the relative deviation between the target and the measuring device exceeds a specified range. It disappears. Further, in this type of displacement measuring device, it is necessary to set the measuring mode of the device depending on the brightness and darkness of the target, but if this setting is incorrect, the device display section will not operate normally and measurement will be impossible. In the above-mentioned conditions, the device operator had to manually re-sight or change the mode setting after visual confirmation. It is clear that in such devices, which are also used to measure minute or short-term displacements, there is a great need to avoid situations where the time required for readjustment is long and the possibility of individual differences among operators occurring. Probably.

SUMMARY OF THE INVENTION An object of the present invention is to provide a non-contact optical displacement measuring device that is equipped with a mechanism that accurately displays the relative relationship between the target and the device, that is, the state of the measurement field of view.

This object is achieved by a non-contact optical displacement measuring device as set forth in the claims, namely: a variable voltage generator for enlarging a measurement field of view by electrical deflection that applies a variable voltage to each deflection coil; an arithmetic processing unit that determines the state of the target by receiving a signal representing the state of the target and a signal representing a preset measurement mode; This is achieved by a non-contact optical displacement measuring device having a measuring field state display mechanism consisting of an alarm section that issues an alarm depending on the alignment with the object.

According to the non-contact optical displacement measuring device according to the present invention, the light and dark direction from evening to target is selected by mode setting with the measurement field of view as the center, and the bright part (or dark part) of the target is set in the set measurable direction. ) exists and the bright/dark boundaries of the target are to the left and right (top and bottom) of the center of the measurement field of view.
It is possible to very easily confirm which mode is to be assigned by a visual alarm such as flickering, lighting, or turning off on an alarm display section on the panel surface, or an audible alarm from a sounding section. Therefore, initial adjustment and readjustment are performed during measurement while visually confirming these displays, so the time required for these is reduced, and accurate adjustment and accurate preparation for measurement are possible.

Conventional adjustments mainly involved operations that relied on the operator's intuition and skill, such as accurately aiming the optical system of the device.
Being able to carry out the measurement while visually checking the status display device, as in the case of the apparatus according to the present invention, has many advantages in terms of shortening the measurement preparation time.

The present invention will now be described in detail with reference to the accompanying drawings showing examples.

FIG. 1 explains the basic configuration of the non-contact optical displacement measuring device according to the present invention, in which a target 1, which is displaced in the direction of a vertical arrow P, is connected to an image dissector tube B by a lens system 2-. 7 An optical image 5 is formed on the otocathode 4. As a result, an electron image 8 is formed near the aperture of the photoelectron multiplier 6 by the photocathode 4 and is displaced in accordance with the target 1 . Changes in the deflection current that should be supplied to the horizontal deflection coil 9 or the vertical deflection coil 10 in order to maintain this electronic image 8 in a predetermined position and keep the output of the multiplier B constant are determined by 11, the horizontal output terminal H and the vertical output. Terminal■
The displacement of the target portion is measured.

In the figure, a discriminator 11 receives the output of the multiplier 6 and generates the required output as a result, a horizontal amplifier 12 associated with each deflection coil 9, 10, a vertical amplifier 13, and a horizontal Detection section 14 and vertical detection section 15
Necessary circuits such as Note that since the image dissector tube 6 has a photoelectron multiplication function, it is generally often referred to as a photomultiplier (abbreviation for photomultiplier), and will be used hereinafter as well.

FIG. 2 is a block diagram of main parts showing an embodiment of the measuring device according to the present invention, and the same parts as in FIG. 1 are given the same reference numerals.

The output based on the image of the bright and dark target 1 captured by the photomultiplier 3 in FIG.

The output of the discriminator 11 is applied to the horizontal deflection amplifier 12 or the vertical deflection amplifier 16 via the horizontal detection amplifier 17 or the vertical detection amplifier 18, thereby activating each deflection coil 9 or 10. In the following description, the lower half circuit also operates in the same manner as the upper half circuit, so its description will be omitted.

A part of the output supplied to the horizontal deflection coil 9 is taken out by the horizontal measuring section 14 as an electrical displacement output signal that compensates for target displacement. The thus extracted output is digitally converted by an A-D converter 19h and applied to a post-processing arithmetic unit CPU 20h. CPU 2
0h receives measurement mode and other setting inputs through the keyboard 21.

The first output 1 of the CPU 20h is the D-A converter 22h
The voltage is applied to the variable voltage generating section 2'5h via. The variable voltage generator 23h selectively applies a variable voltage υ to the horizontal deflection coil 9 automatically or manually, and
It has the function of forcibly deflecting the electron beam in v6 to the right or left.

The second output 11 of the CPU 20h is the mode control section 24h.
is applied to The output of this mode control section 24h and C
The sixth output 111 of the PU 20h is applied to the display control section 25h. The output of the display control section 25h is sent to the display drive section 26.
applied to h. Further, the output of the A-D converter 19h is also directly applied to the display drive section 26h, and display outputs corresponding to these inputs are displayed on the display section Dh. Display part Dh is L
An array of ED or other light emitting elements J4 is suitable, but a double deflection meter or the like can also be used.

The CPU 20h has fourth and fifth outputs and is connected to alarm displays A, , A2 located on both sides of the display section Dh. In addition, a part of the display part Dh can also be used for this warning display tag A2. An alarm display output is generated when the bright/dark boundary of the target is captured by activating the variable voltage generator 25h, that is, when the target deviates from the measurable range, or when the relationship between the setting mode of the keyboard 21 and the target is inconsistent. etc., and the alarm display A1. Both or one of A2 is turned on or flickered. Furthermore, this alarm can be configured to emit an audible alarm by disposing each sounding section.

Figure 3 shows the relationship between the type of target used in the displacement measuring device and the measurement mode. Horizontal and vertical images of the device to be measured Targets corresponding to the two-axis mode as shown in Figure (b) with bright and dark boundaries, and the point-to-point mode as shown in Figure (0) of the device to measure width or thickness, etc. is used.

FIG. 4 shows the display section and alarm display A1. This shows an example of A2, and as shown in Figures (a) to (a), alarm displays A,...
An example of adding A2 and using a part of D is conceivable. It is also possible to use a double deflection meter as shown in Figures (e) and (f). As is clear from the block diagram shown in FIG. 2, such display units are often arranged in two sets, horizontal and vertical, on the panel surface.

FIG. 5 shows the state of the measurement field of view of the displacement measuring device according to the present invention. For displacement measurement, at least the bright/dark boundary of the target is within the field of view A, and therefore -a<y:<a
Alternatively, the relationship -b<y<'b is required, and since the arrangement of brightness and darkness is also determined by the device setting mode, it is also necessary to determine whether this is met. Furthermore, as described above, the device according to the present invention selectively deflects to the field of view B, which is approximately twice as large as this measurement field of view, and determines in which direction the bright/dark boundary of the target has deviated. Is required.

FIG. 6 is a flow chart of preparation for measurement of the displacement measuring device according to the present invention. When the device is set to the measurement state and activated (START), scanning is performed within the field of view captured by the optical system. As a result, if the electronic image of the brightness/darkness boundary of the target is within the measurable range of field of view A, and the direction of brightness/darkness also matches the setting mode, the displacement to be measured will be displayed on the display (Figure 6). Condition I).

If measurement is not possible, the following judgments will be made. If the target is within the field of view but cannot be measured, it means that the mode setting is incorrect, and the warning display tag and A
2 lights up or blinks together to notify the operator (Status ■
). Measurement is possible by setting the measurement mode correctly.

If measurement is impossible and the target bright/dark boundary is outside the field of view A, it is determined whether the target within the field of view A is white (bright) or black (dark).

If the target in the field of view is white (bright),
Applying a deflection voltage from the variable voltage generator to the deflection coil so that the direction of ≦-a, that is, the left side of the field of view A, can be observed;
Determine whether there is a target brightness/darkness boundary. As a result, if the bright/dark boundary of the target is detected, alarm display A, , A2
Only one of them, for example A, lights up, indicating that the bright/dark boundary is on the left side of field of view A. At this time, the display Dh lights up to indicate that the field of view is white (bright) (state ■).
. Re-sighting is performed in accordance with the display, and since the direction of deviation is known in advance, re-sighting is easily performed.

If the target brightness/darkness boundary is not detected in the above operation, it is deflected to the right side of the field of view A (X≧a), and the presence or absence of the target brightness/darkness boundary is similarly determined. If a target is detected, alarm displays A and A2 will light up or blink at the same time, indicating a mode setting error (state
).

Change the setting mode and take measurements.

If the target is not detected by the above operation, measurement will not be possible unless the target is re-aimed and captured at least within the field of view B (state ■).

The bright/dark boundary of the target is outside of field of view A and
If the inside is black (dark), perform the operation toward the right end of the flowchart. That is, a deflection current is supplied from the variable voltage generator to the deflection coil so that the right side of the visual field A can be observed. As a result, if the bright/dark boundary of the target is captured, only the alarm display A2 lights up, indicating that it is off to the right (state ■). Measurement becomes possible by re-aiming.

If the bright/dark boundary of the target is not detected in the above operation, the target is deflected in the opposite direction. As a result, if a target is detected, both the alarm display tag and A2 light up, indicating the incorrect setting mode (state ■). The force can be measured by changing the setting mode.

If the target is not detected by the above operation, measurement will not be possible unless the target is reset and the bright/dark boundary Jl. of the target is captured within the field of view (state ■).

A display indicating that measurement is not possible, such as state V, can be easily implemented by, for example, lighting up all the display sections on the condition that each of the above operations is repeated several times, and adding another display device.

Note that although the above flow chart discloses only the horizontal direction of the field of view, that is, the X direction, it is also carried out in the same way for the vertical direction, that is, the y direction, and it is obvious that in the case of two axes, both are carried out at the same time.

According to the displacement measuring device according to the present invention, confirmation of the measurement field of view and correction to the measurable range can be easily performed. Therefore, displacement can be measured without requiring a high degree of skill or familiarity.

Although only preferred embodiments of the invention have been disclosed, it will be obvious that many modifications and variations may come within its scope.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing the measurement principle of a displacement measuring device according to the present invention. FIG. 2 is a block diagram of a displacement measuring device according to the present invention. Figure 6 shows an example of a measurement target, and Figure (a)
is the target in the -axis mode, Figure (b) is the target in the two-axis mode, and Figure (e) is the target in the two-axis mode. FIG. 4 shows an example of the arrangement of the display section and alarm display. FIG. 5 shows the state of the visual field. FIG. 6 is a flowchart during measurement preparation operations of the displacement measuring device according to the present invention. The correspondence of the main reference symbols is as follows. 1...Target 2...Lens system 6...Image dissector tube (Photomaru)?・・・
・Horizontal deflection coil 10... Vertical deflection coil 20h; 20v... Arithmetic processing unit 21... Keyboard 23h, 23v... Variable voltage generation section D... Display section A4. A2...Alarm display section A...Measurement field of view B...Enlarged field of view

Claims (1)

[Claims] (1) In a non-contact optical displacement measurement device that measures the displacement of an optically captured electronic image of a target, the measurement field of view is expanded by electrical deflection by applying a variable voltage to each deflection coil. a variable voltage generator; a processing unit that receives a signal representing the state of the target within an enlarged field of view and a signal representing a preset measurement mode to determine the state; 1. A non-contact optical displacement measuring device, comprising: an alarm section that issues an alarm depending on whether the target state matches the target deflection direction or setting mode; and a measurement visual field state display mechanism. (2. The non-contact optical displacement measuring device according to claim 1, wherein the alarm section is a display device that issues a visible alarm. (3) The non-contact optical displacement measuring device according to claim 1. In the type displacement measuring device, the alarm section is a sounding device that emits an acoustic alarm.