JPS5829456B2 - Idoubutsu Taikansokusouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for observing (the state of) the surface of a moving object. For example, the present invention relates to a device for observing (the state of) the surface of a moving object. The present invention relates to a moving object observation device suitable for inspecting the condition, color shift, etc., or inspecting the surface condition in a metal rolling process or surface treatment process.

Conventionally, the following methods have been adopted: (a) visual observation with the naked eye, (b) photography, or recording and playback using a combination of a stroboscope, a television camera, and a VTR.
(a) requires skill and is prone to inaccuracy;
B) has the disadvantage that it cannot be determined immediately, and furthermore, ←→ is complicated to operate, and if the object to be measured has a curved surface as shown in Figure 2, it is difficult to focus over the entire surface. be.

The present invention aims to eliminate the drawbacks of the above-mentioned systems and to realize an apparatus that is easy to operate and allows even an unskilled person to perform accurate observation immediately (in near real time).

FIG. 1 is a system configuration diagram showing an embodiment of the present invention.

1 is a sheet-like object to be measured, 2 is a supply roll, and 3 is! 4 is a synchronous signal generator such as a photo encoder, 5
is a TV camera, 6 is a field (or frame)
Memory, 7 monitor TV, 8 stroboscope, 9
1 is a system control circuit, and 10 is an operation button.

Figure 2 shows a part of another embodiment, with figure number lL12.
, 13 are idlers that bring the sheet-shaped object 1 into contact with each other.

Figure 3 shows a part of still another embodiment, with figure number 14.
1 is a part to be measured, and 15 is a conveyor for conveying the object to be measured.

The basic configuration of the present invention consists of a television camera 5 for observing a moving object (object to be measured) 1 in FIG.
The frame will be explained in one field below.

) field memory 6 for recording and reproducing video signals of minutes;
A monitor television 7 for projecting the playback output from the memory on a display tube, an operation button 10 for specifying one frame to be recorded in the memory, a gate signal for extracting the one frame by operating the button, and recording/playback of the memory. It also includes a system control circuit 9 that generates necessary gate signals such as control signals.

Further, if necessary, a synchronization signal generator 4 such as a photo encoder that operates to provide a frequency proportional to the moving speed of the object to be measured 1 is provided, and the horizontal synchronization signal of the television camera is synchronized with the synchronization signal.

At this time, the vertical scanning of the television camera is stopped and the movement of the object to be measured takes its place.

In this way, it is also possible to obtain an image that is in focus over the entire surface even at a curved surface as shown in FIG.

Furthermore, if necessary, a stroboscope 8 with a short flash time may be provided in synchronization with the horizontal synchronizing signal.

Next, the operation will be explained according to FIGS. 6 and 7.

The alphabets b-h in Fig. 6 correspond to the signals b-h in Fig. 7.
It corresponds to

First, when a user wants to observe the surface state of an object to be measured (a moving object), the operator presses the operation button 10.

At this time, as shown in FIG. 7, the system control circuit 9 receives a trigger and sends an erase signal (FIG. 7C) to the field memory 6.

This erase signal erases the signal previously recorded in the field memory 6 (see mode in FIG. 7g).

(This process may be omitted in field memories of a type in which the recorded signal to be updated automatically erases the previous signal.

) Subsequently, the gate circuit 16 is opened by the recording gate signal (FIG. 1d), and the video signal from the television camera passes through the gate circuit 16 for one field period (for example, horizontal scanning line 26).
3) are recorded in the field memory 6.

At this time, it is preferable to perform vertical synchronization so that the timing of the beginning of the gate, that is, the seam of the screen, is at or near the vertical blanking period, since switching noise can be made invisible on the reproduced screen.

There are two methods of photographing with a television camera:

That is, there are two methods: one uses a regular television camera, and the other uses a fixed television camera that only performs horizontal scanning and does not perform vertical scanning.

In the latter case, the object to be measured is moving in one direction at a speed of 11j12t13, .・・・・・・
A signal corresponding to the line is obtained.

Therefore, as shown in FIG. 2, even if the object has a curved surface, it can be brought into focus.

In both of the above-mentioned cases, when this is recorded in a field memory such as a magnetic disk, it is recorded in the form shown in FIG. 5, and this can be reproduced endlessly and repeatedly.

The object to be measured is measured for one field period (approximately 17 m3 in the former method) and for one horizontal scanning period (approximately 64 μS in the latter method).
), the image captured by the television camera will be extended in the direction of travel by the distance traveled, and the resolution will deteriorate accordingly.

This is hardly a problem when the moving speed is relatively slow, but it is a problem when observing an object moving at high speed.

In this case, the stroboscope 8 is used when high resolution is required.

In this case, the horizontal synchronization signal (Fig. 7e, approximately 15.75 KH) from the synchronization signal generator 4 such as a photo encoder
z), the television camera 5 is operated.

At the same time, in order to cause the stroboscope 8 to emit light in synchronization with the synchronization signal e, a flash timing signal (FIG. 7f) is outputted to the stroboscope 8 from the system control circuit 9, which is supplied with the synchronization signal e.

Since the stroboscope is required only during recording, the flash timing signal f is a synchronization signal e gated with a recording gate signal d.

FIGS. 7g and 7h show recording signals recorded in the field memory 6 and their enlarged views.

The flash period of stroboscope 8 is short, for example 0.7
It is set to about ~3 μS, and it is possible to obtain clear, high-resolution images with little screen shake.

Once you have finished recording the video signal for one field in the field memory in this way, switch the memory to the playback state at that timing, play this repeatedly, and display it as a still image on a TV monitor for observation. can do.

Thereafter, the same procedure can be used to freeze and observe the image at the time the operation button is pressed.

[Brief explanation of drawings]

Fig. 1 is a system configuration diagram showing an embodiment of the present invention, Fig. 2 is another embodiment, Fig. 3 is a still further embodiment, Fig. 4 is an explanatory diagram of screen scanning, and Fig. 5 is a field memory. 6 is a circuit block diagram, and FIG. 7 is a time chart of each signal. 1...Object to be measured, 4...Synchronization signal generator, 5...TV camera, 6...Field memory, 7... Monitor TV, 8...
... Stroboscope, 9°°゛°°° system control circuit, 10... Operation buttons.

Claims (1)

[Scope of Claims] 1. A television camera in which vertical scanning is stopped, in which the horizontal synchronizing signal is the output of a synchronizing signal generator exhibiting a frequency proportional to the moving speed of an object to be measured moving in the vertical scanning direction. The video signal corresponding to one scene of the video signal output of the object to be measured by the camera is extracted by a gate signal from the system control circuit triggered by the operation of the operation button, and the extracted output is placed on the concentric track of the field (or frame) memory. A moving object observation device that repeatedly reproduces the signal on the track after storage is completed, and displays the reproduced output on a monitor television. 2. The moving object observation device according to claim 1, wherein a stroboscope whose flash duration is sufficiently short compared to the horizontal synchronization period emits light in synchronization with the horizontal synchronization signal.