JPH0242180B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermography device whose operation can be simplified.

Generally, in a thermography device, infrared rays generated from each point within the field of view are scanned and focused, introduced into an infrared detector, and the obtained detection signal is sent to a cathode ray tube as a luminance signal to distribute the temperature distribution of the object within the field of view. I'm getting a statue. In such thermography devices, the temperature range of the subject is narrower than the measurable range, so there is a knob that changes the temperature range to be displayed, and a center temperature or upper limit (lower limit) temperature (reference temperature) of the temperature range.
It was necessary for the operator to operate the two knobs to adjust the temperature distribution image of the object to be properly displayed on the cathode ray tube.
This adjustment was troublesome, as it had to be done by operating a knob every time you wanted to change the field of view to observe a different subject.

The present invention has been made in view of the above-mentioned problems, and when two desired points in a temperature distribution image are specified using a position specifying means such as a light pen, the temperatures at the two points become the upper limit temperature and the lower limit temperature. It is an object of the present invention to provide a thermography device capable of displaying a temperature distribution image.

An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a configuration diagram showing an embodiment of the present invention, in which 1 is an infrared detector, 2 is an optical scanner for forming an image of the detector on a subject and performing raster scanning, and 3 is a reference blackbody for allowing reference infrared rays to enter the detector every time the optical scanner 2 scans horizontally. Infrared rays from the field of view are sequentially incident on the detector 1 based on raster scanning by the optical scanner 2, and the obtained detection signal is sent via an amplifier 4 to a processing circuit 5 having an absolute temperature reproducing circuit, a linearizer, etc. , is converted into a temperature signal corresponding to the absolute temperature of the subject. The temperature signal is converted into a digital signal by an A-D converter 6, and then sent to an image memory 8 via a write control circuit 7 and stored therein.

9 is a temperature range setting circuit that calculates the temperature range to be displayed based on the signal a specifying the center temperature and the signal b specifying the temperature width; 10 is a setting circuit that reads pixel data stored in the image memory 8; 9, the data of the extracted pixels is transferred to the display image memory 12 in a form that falls within the gradation range of the monitor cathode ray tube display device 11. is stored in The pixel data stored in the memory 12 is read together with the character information pattern data stored in the character display memory 13, and is read out through the DA converter 14, level shift circuit 15, and television signal conversion circuit 16. The signal is sent to a cathode ray tube display device 11 for monitoring.

On the other hand, the character information pattern data read out at the same time as the pixel data is transferred to the level shift circuit 1.
5, and the video signal level is raised to the white level during the period when the pattern exists, so that the screen of the display device 11 displays a temperature distribution image Z and information regarding the image Z, for example, as shown in FIG. CT (center temperature) and TW (temperature width) are displayed superimposed.

17 is a synchronization signal generation circuit that generates standard television synchronization signals H and V to be supplied to the television signal conversion circuit 16; 18 is a pixel clock signal that divides one raster into 256 pixels based on the synchronization signal H; A clock oscillator 19 generates a clock signal, a counter 19 counts the clock signal to generate a horizontal scanning signal, and a counter 20 counts the synchronizing signal H to generate a vertical scanning signal. The memories 12 and 13 store horizontal information from the two counters,
Data is read out based on the vertical scanning signal.

21 is a light pen; 22 is a position determination circuit that determines the indicated position of the light pen based on the signal from the light pen and the horizontal and vertical scanning signals from the counters 19 and 20; 23 is a position sent from the determination circuit 22; A conversion circuit converts data into an address specifying the corresponding pixel in the memory 8; 24 is a shift register for holding the temperature data of the specified pixel read out based on the address signal from the conversion circuit 23; 25 is a shift register for holding the temperature data of the specified pixel read out based on the address signal from the conversion circuit 23; A subtraction circuit that simultaneously reads out two pieces of data held in the shift register 24 and calculates their difference, and an average circuit that calculates the average value; 26 is an average circuit that also calculates the average value;
Reference numeral 27 denotes a character writing circuit for writing the temperature width signal b obtained as the output of the subtraction circuit 25 and the center temperature signal a obtained as the output of the averaging circuit 26 into the character display memory 13.

In the above configuration, the image memory 8 has 256 pixels in the horizontal direction and 256 pixels in the vertical direction, as shown in FIG.
A storage area of 240 lines and, for example, 12 bits in the depth direction is set, and the temperature data of each pixel obtained by horizontally and vertically scanning the detector image with the optical scanner 2 is stored at the corresponding position. Stored. Image display memory 12, character display memory 1
3, as shown in Figure 4, is exactly the same as Figure 3256
A storage area for ×240 pixels is set,
In the depth direction, the image display memory 12 stores 6 bits (64
gradation), 1 bit (white,
2 gradations of black).

Now, if the center temperature (CT) is specified as 35.0℃ and the temperature width (TW) is specified as 3.00℃, then
The temperature range setting circuit 9 calculates CT±TW/2,
The lower limit temperature (33.5°C) and upper limit temperature (36.5°C) are specified to the read selection circuit 10. The read selection circuit 1
0 is from all pixels stored in image memory 8
Extract those above 33.5℃ and below 36.5℃, Part 3
The temperature is classified into 62 levels from 1 to 62 within the temperature range of 0.degree. C., and the numerical values are written into the corresponding positions of the image display memory 12. In addition, “0” (black level) is applied to pixels below 33.5℃.
is assigned, and "63" (white level) is assigned to pixels with a temperature of 36.5 degrees Celsius or higher, making a total of 64 gradations.

Further, the character writing circuit 27 controls the character generator based on the signal a specifying the center temperature and the signal b specifying the temperature range, and writes the character display memory 13
``CT35.0'' is displayed at the top of the 256 x 240 storage area.
TW3.00'' is written in the form of a 5 x 7 dot matrix, for example. In this case, since it is sufficient to indicate the presence or absence of a pattern, the memory 13 only needs to have one bit in the depth direction.

The image data and character data written separately in the memories 12 and 13 in this way are simultaneously read out in synchronization with the screen scanning of the display device 11 by horizontal and vertical scanning signals generated from the counters 19 and 20. Image data is sent to the display device 1 via a D-A converter 14, a level shift circuit 15, and a conversion circuit 16.
1, a temperature distribution image Z as shown in FIG. 2 is displayed on the screen.

Also, the character data is sent to the level shift circuit 15, and the level shift circuit 15 changes the video signal to white level only when a character pattern exists, so it is superimposed on the temperature distribution image Z and becomes "CT35.0 TW3. 00"
characters are displayed.

In the present invention, when the image is displayed in this way, when two desired points in the temperature distribution image are specified using a position specifying means such as a light pen, the temperatures at these two points are set as the upper limit temperature and the lower limit temperature. The feature is that an image corresponding to a newly set temperature range between the upper limit temperature and the lower limit temperature is displayed.

That is, if an operator observes an image Z in the range of 33.5°C to 36.5°C as shown in FIG. 2 and wishes to observe in detail the temperature range between points P and Q, the operator First of all, TW on the screen
and press the switch on the light pen 21. While the switch is pressed, a pulse is generated from the light pen at the timing when the letters TW are displayed (lit), so the position discrimination circuit 2
2 determines that TW is instructed based on the pulse and the horizontal and vertical scanning signals sent from counters 19 and 20, and generates a determination signal w. Conversion circuit 2
3 is activated by the signal w.

Next, the operator presses the light pen 21 against a desired point P in the temperature distribution image Z and presses the switch again. A pulse synchronized with the display of point P is obtained from the light pen, and the position discrimination circuit 22 holds the horizontal and vertical scanning signals at the time when the pulse is generated, and sends the value to the conversion circuit 23 as the position signal of point P. send. The conversion circuit 23 generates an address signal specifying a pixel in the image memory 8 corresponding to the point P in the image Z based on the scanning signal value, and sends the address signal to the image memory 8. The temperature data at point P read from memory 8 based on the address signal is held in register 24.

Furthermore, when the operator places the light pen on the desired point Q and presses the switch, the light pen will point out the point Q.
A pulse synchronized with the display of is obtained, and the temperature data of the pixel corresponding to point Q in the memory 8 is read out based on the pulse and held in the shift register 24 in exactly the same manner as described above. and a subtraction circuit 25,
The averaging circuit 26 simultaneously reads out the temperature data of points P and Q held in the register at this point.
Calculate the difference and average value. For example, if the temperatures at points P and Q are 35.8°C and 33.8°C, respectively, the output of the subtraction circuit 25 will be 2.0°C, and the output of the averaging circuit 26 will be 34.8°C. The output of the subtraction circuit 25 is sent as a temperature width signal b, and the output of the averaging circuit 26 is sent as a center temperature signal a to the write circuit 27 and the setting circuit 9, respectively.

The setting circuit 9 receives the newly sent signal a.
(34.8℃), CT described above based on signal b (2.0℃)
Calculate ±TW/2 and new upper limit temperature 35.8
℃, set the temperature range with a lower limit temperature of 33.8℃. Based on the upper limit temperature and lower limit temperature, the readout selection circuit 10 extracts only pixel data within the set temperature range and stores it in the image display memory 12, in exactly the same manner as described above, so that the monitor display device 11 has a point P. A temperature distribution image with a temperature width of 2° C. is displayed, with the upper limit temperature being 35.8° C. and the lower limit temperature being 33.8° C. at point Q.

The signals a and b are also sent to the character writing circuit 25, and the writing circuit 25 rewrites the value of CT in the memory 13 to "34.8" and the value of TW to "2.00", respectively, on the screen of the display device 11. The numerical value displayed is also "CT34.8 TW2.00", which correctly represents the display conditions of the temperature distribution image.

As mentioned above, in the present invention, by simply specifying two specific points, an image in which the temperatures at those two points are the upper and lower limit temperatures can be obtained, so it is not necessary to manually adjust the center temperature and temperature range by operating knobs. The temperature range between two desired points can be specified without setting, which greatly improves operability.

Note that in the above-mentioned embodiments, in order to facilitate understanding, a device composed of individual blocks was illustrated.
Actually, the position determination circuit 22 and the address conversion circuit 2
3. The functions of the temperature range setting circuit 9, the subtracting circuit 25, the averaging circuit 26, the read selection circuit 10, etc. can be replaced by a computer.

Furthermore, in the above-described embodiments, the present invention was implemented in an apparatus that uses the center temperature as the reference temperature necessary for specifying a temperature range, but the lower limit temperature and temperature range or the upper limit temperature and temperature range are used to specify the temperature range. It goes without saying that the present invention can be carried out in exactly the same manner with respect to an apparatus using the same.

Furthermore, since the light pen cannot detect its position unless the screen is illuminated, it is impossible to specify a pixel at the black level in the temperature distribution image Z, that is, a pixel whose temperature is below the lower limit temperature. In that case, for example, by increasing the brightness of the entire screen only while the light pen switch is pressed, light can be detected and the position of a pixel at the black level can be detected. You can specify the temperature and read the temperature data.

Furthermore, in the above-described embodiment, a light pen is used as a position specifying means, but the present invention is not limited to this. For example, by placing a sheet on which transparent electrodes are arranged in close contact with the screen and pressing the sheet with a finger, an arbitrary point on the screen can be specified. It goes without saying that other position specifying means such as a so-called touch sensor that can specify a position may also be used.

Furthermore, in the embodiment described above, a center temperature signal a and a temperature width signal b are once created from the temperature data of points P and Q, and the signals a and b are sent to the setting circuit 9 to calculate the upper limit temperature and lower limit temperature again. However, the temperature data at points P and Q stored in the register 24 may be sent directly to the read selection circuit 10.
However, even in that case, a subtraction circuit and an averaging circuit are necessary to generate the center temperature signal a and the temperature width signal b to be sent to the write circuit 27.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of an embodiment of the present invention, FIG. 2 is a diagram showing the display state of the screen, FIG. 3 is a diagram showing the pixel arrangement in the image memory 8, and FIG. 4 is for image display. FIG. 2 is a diagram showing the arrangement of pixels in the memory 12 and the character display memory 13. FIG. 8: Image memory, 9: Temperature width setting circuit, 10:
readout selection circuit, 11: cathode ray tube display device for monitor, 12: memory for image display, 13: memory for character display, 14: D-A converter, 15: level shift circuit, 16: television signal conversion circuit, 17: synchronous signal generation circuit, 18: pixel clock oscillator, 19,
20: Counter, 21: Light pen, 22: Position discrimination circuit, 23: Address conversion circuit, 24: Shift register, 25: Subtraction circuit, 26: Average circuit,
27: Character writing circuit.

Claims (1)

[Claims] 1. A means for storing temperature data of pixels constituting a field of view obtained by detecting infrared rays from a subject, and a temperature range determined by the specified upper and lower temperature limits of the temperature data stored in the storage means. a reading means for reading out what is inside; a display means for displaying the temperature distribution of the subject based on the read temperature data; a position specifying means for specifying an arbitrary position on the screen of the display means; means for generating an address signal for designating a pixel corresponding to a position designated by the position designation means among the pixels stored in the storage means, and the pixel is read out from the storage means based on the address signal. A thermography apparatus characterized in that temperature data of two pixels are used as the upper limit temperature and the lower limit temperature.