JPH0441325B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Technical Field of the Invention The present invention relates to a scanning method that mechanically performs horizontal and vertical scanning of an object, and particularly relates to a scanning method that allows scanning to be controlled from the outside. It is.

(b) Background of the technology In recent years, devices have been put into practical use that detect infrared rays emitted by an object, display its surface temperature pattern (thermogram) in a short time, and accurately and quickly measure the temperature at each point. There is. As the scanning means of the infrared imager used in such an apparatus, one that mechanically performs horizontal scanning and vertical scanning is used. Such scanning means will be explained using FIG. 1.

FIG. 1 is a block diagram of the scanning means.

In the figure, there is a gimbal 2, and the gimbal 2
A scanning mirror 3 that can vibrate horizontally is attached to the gimbal 2 by a torsion bar 4, and a rotating shaft 5 that can rotate vertically is attached to the gimbal 2, forming horizontal scanning and vertical scanning means. has been done. Such scanning means is a torsion bar 4.
While horizontal scanning is performed by vibrating the scanning mirror within a certain angle in the horizontal direction, vertical scanning is performed by vibrating the cymbal 2 back and forth (up and down) within a certain angle around the rotation axis 5. A plurality of horizontal scans are performed during one round trip of scanning, and all scanning of the object is completed.

(c) Prior Art and Problems An example of a conventional scanning method using such a scanning means will be described below.

In the conventional scanning method, the horizontal scanning drive shown in Fig. 1 involves exciting two pairs of vibrating coils with a 60Hz repetitive signal, and rotating the rotating shaft 5 using a DC (direct current) motor. .

Furthermore, in recent years, the scanning of the above-mentioned scanning means can be controlled to display a temperature pattern synchronized with the load applied to the object using a device that detects the infrared rays emitted by the object and displays its surface temperature pattern. Device is requested. however,
Conventional scanning methods use a DC motor for vertical scanning, and since this DC motor rotates at a constant speed with a constant voltage, it has the disadvantage that the scanning step of the scanning means cannot be controlled by an external signal. Ta.

(d) Purpose of the Invention In view of the drawbacks of the conventional scanning method, it is an object of the present invention to provide a scanning method that does not cause a scanning position shift during reciprocating vertical scanning and can control the scanning step using an external signal. It is said that the purpose is

(e) Structure of the invention In order to achieve the above object, the present invention first has the following features:
One is a scanning method consisting of a scanning means that mechanically performs horizontal and vertical scanning of the subject, and the scanning means includes a horizontal scanning means and a vertical scanning means that reciprocate in the vertical direction while vibrating a scanning mirror in the horizontal direction. The horizontal scanning drive means for driving the horizontal scanning means is provided with a means for outputting a pulse every time the horizontal scanning means completes one horizontal scan, and the pulse output from the horizontal scanning means and the external The second feature is that a switching means for switching and outputting a pulse is provided, and a vertical scanning drive means for driving a vertical scanning means is operated for each pulse output from the switching means. In a scanning method that mechanically performs horizontal and vertical scanning of a subject, a vertical scanning start position setting input means for setting a vertical scanning starting position and a vertical scanning means for performing vertical scanning are driven every time one horizontal scanning is completed. The present invention is characterized in that it includes a driving means and a control means for controlling the number of horizontal scans during one vertical scan so that it is constant in both directions, and the scanning range can be set.

(f) Embodiment of the Invention Hereinafter, an embodiment of the scanning method of the present invention will be described in detail with reference to FIGS. 2 and 3.

FIG. 2 is a configuration diagram of an embodiment of the scanning method of the present invention. In the figure, parts that are the same as those in FIG. A motor, 8 is a step motor drive circuit that drives the step motor 7, 9 is a horizontal scanning drive coil, 10 outputs a signal matching the natural frequency of the torsion bar and scanning mirror to the horizontal drive coil 9, Z per horizontal scan
This is a horizontal scanning drive circuit that outputs horizontal pulses from its terminals. The step motor and the step motor drive circuit 8 constitute vertical scanning drive means.
Further, the horizontal scanning driving coil 9 and the horizontal scanning driving circuit 10 constitute horizontal scanning driving means.
11 counts up and down the pulses input from the a terminal when the d terminal force is "1" according to the signal accompanying the vertical scanning reciprocating vibration input to the Down terminal or the Up terminal, and counts the pulse from the C terminal. In addition to outputting the value, an up/down control signal is output from the b terminal to the a terminal of the step motor drive circuit 8 depending on whether up-counting or down-counting is currently being performed, thereby controlling the reciprocating vibration of vertical scanning. The inverting up/down counter 12 is a converter 13 which compares the count value from the C terminal of the up/down counter 11 with a preset value and outputs a control signal from the a terminal or the b terminal. When the reset signal is input from the C terminal, a is set by the number of times setting signal input from the number of times setting input terminal A.
After counting the pulses input to the terminal, the number set by the start count number setting signal input from the start count number setting input terminal B,
A start control circuit that counts pulses input to the b terminal and outputs a "1" level signal from the d terminal when the count is finished; 14 is a power reset; G ₁ to G ₃ are OR gates; G ₄ and G ₅
is an AND gate, INV is an inverter, X is an external control signal input terminal, and Y is a horizontal pulse output terminal.

FIG. 3 is an explanatory diagram of the operation in FIG.
2. thru|or P each show the signal waveform at each point a thru|or P of FIG. 2.

In FIG. 2, horizontal scanning is performed by driving a horizontal scanning driving coil 9 in response to a driving signal from a horizontal scanning driving circuit 10 and vibrating the scanning mirror. Further, in vertical scanning, the step motor 7 is driven by a drive signal from the step motor drive circuit 8, rotates the rotary shaft 5, and rotates the gimbal 2.
This is done by reciprocating the vibration.

First, a case will be described in which scanning is not controlled by an external control signal input to the external control signal input terminal X.

In this case, the switch _S2 is closed, supplying earth to one terminal of the AND gate _G5 , closing the AND gate _G5 , and inhibiting the external control signal input to the external control signal input terminal X.

Therefore, in this case, the output of the AND gate _G5 is fixed at the "0" level as shown in Figure 3m, and since the inverter INV is supplied with earth air, the output of the inverter INV is is fixed at the "1" level as shown in FIG. 3k.

Further, in the horizontal scanning drive circuit 10, the horizontal pulse shown in FIG. 3h is output from the Y terminal to the AND gate _G4 every time one horizontal scan is performed. Therefore, the output of the AND gate _G4 is such that the horizontal pulse is output as is, as shown in FIG.
Furthermore, as shown in FIG. 3n, the output of the OR gate _G3 also outputs the horizontal pulse as it is. Therefore, in this case, the horizontal scanning drive circuit 10 is connected to the a terminal of the up/down counter 11.
A signal with the same timing as the horizontal pulse is input. Further, a horizontal pulse is input to the b terminal of the start control circuit 13.

Now, at time _t1 in FIG. 3, the reset signal is output to the start control circuit 1 by the power supply reset 14 or switch _S1 , as shown in FIG.
Suppose that it is added to 3. From this point on, the start control circuit 13 counts the pulses from the upper limit switch 6a the number of times set by the number setting signal input to the number setting input terminal A. For example, if the number of times set by the number of times setting signal input to the number of times setting input terminal A is "2", as shown in _FIG . The pulses from the upper limit switch 6a shown in b are counted by "2". and,
In the start control circuit 13, when the number set by the number setting signal input to the number setting input terminal A matches the number of pulses counted from the upper limit switch 6a, from that point on, the pulse input to the b terminal is stopped. , counts the number set by the start count number setting signal inputted to the start count number setting input terminal B, and sets the start position of vertical scanning. For example, if the number set by the start count setting signal input to the start count setting input terminal B is "B" as shown in the third diagram, then
The output of the Z terminal of the horizontal scanning drive circuit shown in FIG. 3h is counted by "B". Then, in the start control circuit 13, when the number set by the start count number setting signal inputted to the start count number setting input terminal B matches the number counted of pulses from the Z terminal of the horizontal scanning drive circuit, the d terminal From that point on, a "1" level pulse is output as shown in FIG. 3p.

The set number input to the start count number setting input terminal B is a set number for determining the imaging start position of the object when scanning and imaging the object to be scanned. That is, in FIG. 3, when the reset signal shown in FIG. _3a is input at point t1, the start control circuit 13 performs the following:
From time _t1 , pulses from the upper limit switch 6a are started to be counted. When the pulses from the upper limit switch 6a are counted by the number set by the number of times setting signal, counting of pulses shown in FIG. _3h is started from time t3. Then, the number of horizontal scanning drive circuits Z is set by the start count setting signal.
When we count the pulses from the terminal, at that time t ₄
3, outputs a "1" level signal as shown in FIG. 3P.

In this way, until the start control circuit 13 outputs a "1" level signal from the d terminal, that is, from t ₁ to t ₄ in FIG.
In the up/down counter 11, the OR gate G3 shown in FIG. 3n is activated in response to the down control signal from the upper limit switch 6a shown in FIG. 3b or the up control signal from the lower limit switch 6b shown in FIG. _3c. Count down or up the pulses from. That is, after the pulse shown in FIG. 3B is input, a down count is performed, and after the pulse shown in FIG. 3C is input, an up count is performed. Then, depending on the counting state, that is, whether it is an up-counting state or a down-counting state, b
The terminal outputs up/down control signals to the step motor drive circuit 8 as shown in FIG. 3o.
Further, the up/down count 11 always outputs the count value to the comparator 12. Then, in the step motor drive circuit 8,
Drive control of the step motor 7 according to the up-down control signal from the b terminal of the down counter 11;
This reverses the reciprocating drive scan of the vertical scan. Incidentally, the step motor 7 is driven every time a pulse, which is the output of the OR gate _G3 shown in FIG.

At time t ₄ in FIG. 3, P as shown in FIG. 3 is output from the d terminal of the start control circuit 13.
The “1” level signal shown in
input to the C terminal. The comparator 12 constantly compares the count number of the up/down counter 11 with a preset number P while inputting the "1" level signal from the start control circuit 13, and determines whether the counter number is When it becomes P, “1” is output from the a terminal as shown in Fig. 3e.
It outputs a level pulse and enters the UP state. Similarly, when the count reaches P in the up state, a "1" level pulse as shown in FIG. 3d is output from the b terminal. Therefore, after time _t4 in FIG. 3, the up-down counter 11 can set the number of horizontal scans in one vertical scan based on the set value of the comparator 12.

As described above, the present invention allows the rotating shaft 5 to move between the upper limit switch 6a and the lower limit switch 6b several times from the input of the reset signal, and after a predetermined number of times, the rotating shaft 5
contacts the upper limit switch 6a, after counting the horizontal pulses output for each scan a predetermined number of times, the vertical scanning means is enabled to reciprocate every predetermined number of horizontal scans, and the number of horizontal scans in one vertical scan is reduced to a reciprocating number. This allows control so that both values remain constant.

In addition, when controlling the scanning step by an external control signal input to the external control signal input terminal X, switch S ₂ , OR gate G ₄ ,
The outputs from the switching means consisting of _G5 and the inverter INV can be switched by opening the switch _S2 . That is, when the switch _S2 is in the open state, a "1" level signal is input to one input terminal of the AND gate _G5 .
The output of Ungate _G5 corresponds to the external control signal. Also, since the output of the inverter INV is at the “0” level, the AND gate
_G4 is in a closed state, and the output of AND gate _G4 is at the "0" level. Therefore, the external control signal is input as a pulse from the OR gate _G3 to the a terminal of the up/down counter 11, and the step drive circuit can be operated by the pulse from the external control signal.

(g) Effects of the Invention As explained above in detail, according to the scanning method of the present invention, the scanning step can be controlled by operating the vertical scanning driving means by an external signal, and the number of scanning can be controlled by a counter. Since it is always set, there is no scanning position shift, and since the scanning step can be controlled by an external signal, it is possible to obtain the effect of having a degree of freedom.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a scanning means, FIG. 2 is a block diagram of an embodiment of the scanning method of the present invention, and FIG. 3 is an explanatory diagram of the operation of FIG. 2. In the figure, 1 is a scanning means, 2 is a gimbal, 3 is a scanning mirror, 4 is a torsion bar, 5 is a rotating shaft, 6a is an upper limit switch, 6b is a lower limit switch, 7 is a step motor, 8 is a step motor drive circuit, and 9 is horizontal a scanning drive coil, 10 a horizontal scanning drive circuit, 11 an up/down counter, 1
2 is a comparator, 13 is a start control circuit, 14 is a power supply reset, _G1 to _G3 are OR gates, _G4 and _G5 are AND gates, and INV is an inverter.

Claims (1)

[Claims] 1. In a scanning method comprising a scanning means that mechanically performs horizontal and vertical scanning of a subject, the scanning means includes a horizontal scanning means that vibrates a scanning mirror horizontally and reciprocatingly in the vertical direction; The horizontal scanning driving means for driving the horizontal scanning means is provided with a means for outputting a pulse each time the horizontal scanning means completes one horizontal scanning, and the pulse outputted from the horizontal scanning means. , a switching means for switching and outputting external pulses is provided, and for each pulse output from the switching means,
A scanning method characterized by operating a vertical scanning drive means for driving a vertical scanning means. 2. In a scanning method that mechanically performs horizontal and vertical scanning of a subject, the vertical scanning start position setting input means for setting the starting position of vertical scanning and the vertical scanning means for performing vertical scanning are driven every time one horizontal scan is completed. 1. A scanning method comprising: a drive means for controlling the number of horizontal scans during one vertical scan; and a control means for controlling the number of horizontal scans during one vertical scan so as to be constant in both directions, and the scanning range can be set.