JP2001183460A - Display method of infrared detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display method of an infrared detecting device for displaying an infrared image, heading direction, azimuth of a flight object near it, and an estimated distance to and elevation of the object, visually, easily to recognize, when displaying the omnidirectional infrared image. SOLUTION: The display method comprises an entirely circumferential image memory means for accumulating an omnidirectional image signal from an infrared sensor at an omnidirectional image data, an address converting means for converting the omnidirectional image data to an omidirectional infrared image signal displayable in a circular shape, a scan converting means for creating a PPI image indicating the distance on a concentric circle with the omnidirectional infrared image signal or an elevation information image signal, piling a emblem, based on desired information of the object from a signal processing means for extracting the object on the created signal, and converting it to a display format, and a display means for displaying the image signal converted to the display format.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display system for displaying an infrared image or the like in a full-circle scanning infrared detection device.

2. Description of the Related Art An all-round scanning type infrared detecting device mounted on a ship or the like detects and tracks infrared rays radiated from a target object such as an aircraft or a missile that is heading or approaching in 360 degrees in all directions. When displaying information of an object on a display together with an image, it is required to display the image and the orientation of the target object in a visually easy-to-understand manner, including the estimated distance to the target and the high angle.

[0003]

2. Description of the Related Art FIG. 9 is a view for explaining the principle of a conventional infrared detecting device, wherein 1 is an infrared sensor unit, 2a is a signal processing unit, and 3a
Is an entire-circumference image memory unit, 4a is a scan conversion unit, 5 is a display unit, and 11 is an optical system, 12 is an infrared imaging device, 1
3 is an AD converter and 14 is a gimbal.

The infrared sensor section 1 comprises an optical system 11, an infrared imager 12, an A / D converter 13, and a gimbal 14.

In the infrared sensor section 1, the optical system 11 condenses the incident infrared light, and the condensed infrared light is sent to the infrared imaging device 12, and the infrared imaging device 12 converts the infrared light into an infrared image signal of an analog electric signal. The analog signal is sent to an AD converter 13, which converts the infrared image signal of the analog electric signal into a digital signal.

On the other hand, the gimbal 14 has three axes of a pitch axis, a roll axis, and a yaw axis having a function of correcting the sway,
The optical system 11, the infrared imager 12, and the AD converter 13 are fixedly installed on a gimbal 14.

Accordingly, in the infrared sensor section 1, when the gimbal 14 turns at a speed of, for example, one revolution / second, a 360-degree omnidirectional digital infrared image signal is obtained, and the gimbal 14 corresponds to the infrared image signal. Is transmitted to the signal processing unit 2a and the full-circumference image memory unit 3a.

The signal processing unit 2a performs a point target filtering process and an infrared reception intensity calculation process on the infrared image signal, and detects an image portion where the infrared reception intensity increases as a heading / approaching target object. The azimuth information of the target object is sent to the scan converter 4a.

The full-circle image memory section 3a stores the infrared image signal as data.

In the scan conversion section 4a, the omnidirectional image memory section 3
a, the symbol character is superimposed on a corresponding portion of the data based on the azimuth information of the target object from the signal processing unit 2a, and the heading information of the ship from the gyro system is also obtained. The data is superimposed, and the superimposed omnidirectional data is divided into a plurality of data such as three or four, edited on one screen, and a television screen converted to a television scanning display format is transmitted to the display unit 5. .

The display section 5 displays the television screen on a display.

In addition, separately from the above, an image portion in an arbitrary direction on the television screen can be enlarged and displayed by separately designating the same.

FIG. 10 shows a conventional display example of an omnidirectional infrared image and an enlarged display example of an arbitrary azimuth, and shows the contents described in FIG.

Reference numeral 71 denotes a display; 72, a first azimuth image; 73, a second azimuth image; 74, a third azimuth image;
5 is a symbol mark of the first target object, 76 is a symbol mark of the second target object, 77 is a heading display, and 78 is an enlarged display image.

The image displayed on the display 71 is obtained by converting the 360-degree omnidirectional infrared image described in FIG. 9 into a first directional image 72, a second directional image 73, and a third directional image 74. It is divided into three and displayed on the same screen. That is, assuming that the reference direction (true north) is 0 degrees, the first direction image 72 is a second direction image 7 from 0 degrees to 120 degrees.
3 is a third azimuth image 74 from 120 degrees to 240 degrees
Are images from 240 degrees to 360 degrees (0 degrees).

The symbol mark 75 of the first target object indicates one detected target object, and the symbol mark 76 of the second target object indicates another detected target object. The heading display 77 indicates the heading of the ship on which the infrared detection device is mounted.
That is, FIG. 10 shows that the one target object exists in the same direction as the bow.

Further, the enlarged display image 78 can be obtained by separately designating the azimuth of the symbol mark 75 of the first target object displayed in the first azimuth image 72 to indicate the dotted line in the first azimuth image 72. This is another screen with an expanded range.

[0018]

Accordingly, in order to divide the omnidirectional infrared image into a plurality of images and display them on one screen, the azimuth is numerically displayed together, but the true azimuth or the ship of the own ship is used. When the head direction is used as a reference, there is a problem that it is difficult to comprehend the direction from which the target object comes, and further, the high angle (the angle in the height direction with respect to the horizontal plane) of the target object.

Also, unlike an active sensor which detects a reflected wave of a radio wave emitted from a target object such as a radar, the infrared detection device is a passive sensor which unilaterally detects infrared rays emitted from the target object. There is also a problem that the distance to the object cannot be determined, and therefore the distance cannot be displayed on the image.

In view of this problem, the present invention provides a 360-degree omnidirectional image which is displayed in an easily comprehensible manner, including not only the azimuth of the target object but also the estimated distance and the high angle as information of the target object. An object of the present invention is to provide a scanning infrared detection device.

[0021]

In order to achieve the above object, in a display method of an infrared detecting apparatus according to the present invention, an omnidirectional image signal captured by an infrared sensor is stored as omnidirectional image data. Circumference image memory means, address conversion means for converting the omnidirectional image data into an omnidirectional infrared image signal that can be displayed in a circular shape, and the angle information of the heading and approaching object extracted from the signal processing means. Scanning conversion means for superimposing a symbol mark based on the omnidirectional infrared image signal and converting the same into a display format; and display means for displaying the image signal converted into the display format.

Further, in the display method of the infrared detecting apparatus according to the present invention, the scan conversion means can display the object from the signal processing means, which can be displayed concentrically with an omnidirectional infrared image signal on which the symbol mark is superimposed. Scan conversion means for generating a PPI image signal with a symbol mark based on the distance information of the PPI.

In the display method of the infrared detection device according to the present invention, the signal processing means measures an S / N ratio corresponding to the object in the omnidirectional image signal every time the infrared sensor means scans. A signal processing means for calculating a distance to the object from the S / N ratio and an S / N ratio of the object calculated based on a previously input weather condition and a target condition assuming the object. It may be.

Further, in the display method of the infrared detecting device according to the present invention, the scan conversion means may transmit distance information of the object from the signal processing means and the infrared sensor means separately from the omnidirectional infrared image signal. Scan conversion means for generating a high-angle information image signal with a symbol mark corresponding to the object based on the high-angle information originating from the terminal and converting the signal into a display format may be used.

In addition, in the display method of the infrared detecting device according to the present invention, the scan conversion means separates the omnidirectional infrared image signal and the PPI image signal by a display switching instruction including azimuth information. Scanning conversion means for generating an enlarged designated azimuth image signal of a portion corresponding to the azimuth information in the azimuth infrared image signal and converting it into a display format may be used.

An object approaching or approaching is extracted from the omnidirectional image signal captured by the infrared sensor, and the S
/ N ratio is measured, and the S / N ratio is calculated from weather conditions (temperature, humidity, visibility) input in advance and target conditions (area and speed assuming the type of the object) and the like. Then, target information including the distance calculated from and the angle information (azimuth and high angle) of the object is generated.

On the other hand, the omnidirectional image signal is stored as omnidirectional image data, and the omnidirectional image data is converted so that the omnidirectional image data can be displayed in a circular shape, and a symbol mark is placed at the position of the object based on the target information. A single omnidirectional infrared image signal and a PPI image signal that can be displayed concentrically with the omnidirectional infrared image signal and indicate the distance of the object by attaching a symbol mark based on the target information. indicate.

In response to a display switching instruction for high-angle display,
Based on the target information, a high-angle information image signal indicating a distance and a high angle of the object is generated and displayed on a screen. Further, in response to a display switching instruction including azimuth information, an enlarged designated azimuth image signal of a portion corresponding to the azimuth information in the omnidirectional infrared image signal is generated and displayed on a screen.

Therefore, it is possible to easily and visually display the screen including the estimated distance to the target and the high angle in addition to the infrared image and the azimuth of the target object.

[0030]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram illustrating the principle of the present invention, and FIG. 2 is an example of memory mapping according to the present invention.

In FIG. 1, reference numeral 1 denotes an infrared sensor unit, 2 denotes a signal processing unit, 3 denotes an entire image memory unit, 4 denotes a scan conversion unit,
Reference numeral 5 denotes a display unit, and 6 denotes an address conversion unit.

In the infrared sensor section 1, a 360-degree omnidirectional digital infrared image signal obtained by turning and angle information (azimuth and high angle) corresponding to the infrared image signal are transmitted to the signal processing section 2 and the entire circumference. It is sent to the image memory unit 3.

The signal processing unit 2 performs a filtering process for extracting a point-like target and an infrared reception intensity calculation process on the omnidirectional infrared image signal from the infrared sensor unit 1 to detect an image portion where the infrared reception intensity increases. It is detected as a heading or approaching target object. That is, since the object detected as the target is initially located at a long distance, it is point-like on the image. As the object comes closer, the size of the object increases on the image and the intensity of the infrared reception increases.
The ratio (signal-to-noise ratio) is observed as a gradually increasing signal. Then, the S / N ratio value corresponding to the detected target object and the angle information from the infrared sensor unit 1 are accumulated for each scan (each time the infrared sensor unit 1 turns once).

When the measured S / N ratio exceeds a certain value, it is regarded as "a target object to be a threat".

Since the measured S / N ratio value varies, the rate of increase of the S / N ratio value is calculated from the measured S / N ratio value for each scan by least squares approximation. . That is, the conversion S / S by the least square approximation operation at the time of the n-th scan
The N ratio value Q (n) is as follows: Q (n) = be ^{an an} (1)

However, a and b are obtained as solutions of the following two equations.

[0038] n · logb + (Σt) · a = ΣlogZ (t) (Σt) · logb + (Σt 2) · a = Σt · logZ (t) here, t is the variable (t = 1,2, ·· n ) And Z
(T) is the S / N ratio value measured at the time of the t-th scan.

Further, based on the angle information (azimuth and high angle), the coordinates of the center of the target object detected are shown in FIG.
As in (x ₁ , y ₁ ).

On the other hand, detection S /
The N ratio value is as follows: S / N = τ (R) × P / NEP──── (2)

Here, τ (R) is the infrared transmittance in the atmosphere at the distance R, and is calculated from the weather conditions (temperature, humidity, visibility) and the wavelength band of the infrared light by using an air transmittance calculation model (LOWTRA).
N: published by the U.S. Air Force Geophysical Laboratory). NEP (abbreviation of Noise Equivalent Power) is an infrared radiation intensity that is equal to sensor noise and is a constant value for each sensor device. P is the infrared radiation intensity emitted by the target object, and P = S∫ ((C ₁ / λ ⁵ ) / (exp (C ₂ / λT) −1)) dλ.

Here, S is the area of the target object, λ is the infrared wavelength and is a variable, C ₁ and C ₂ are constants, and T is the temperature of the target object and is determined by the speed of the target object. That is, T = T _a (1 + γ ((γ−1) / 2) M ² ), where γ is a constant, M is speed, and _Ta is temperature.

Accordingly, P is determined by inputting the area and speed of the target object, assuming the type of the target object, based on the temperature and the situation where the ship on which the infrared detection device of the present invention is mounted is placed. Can be done.

Then, the distance to the target object is determined by comparing the converted S / N ratio value calculated by the least squares approximation calculation in the expression (1) with the detected S / N ratio value calculated in the expression (2). Can be estimated. Then, the coordinates (x ₁ , y ₁ ) for the target object, the obtained estimated distance, and information on whether or not the target is a threat are sent to the scan conversion unit 4 as target information.

The full-circle image memory unit 3 stores the digital infrared image signal as data.

Here, in FIG. 2, (A) is a writing map of the full-circumference image memory unit 3, and 31 is accumulated data for one scan obtained by the infrared sensor unit 1 making one turn. An example in which the data is stored as (x, y) coordinates is shown. Here, 360,000 samples of the azimuth (θ) are accumulated in the x-axis direction as 30,000 samples in the horizontal direction, and up to 2.4 degrees with the base angle of 0 degree as the height and 200 in the vertical direction as the height. The example which accumulated the sample in the y-axis direction is shown. The base angle can be arbitrarily set by the infrared sensor unit 1, and the accumulated data 31 from the base angle to the base angle plus 2.4 degrees.

(B) is a map corresponding to the display screen, 71 is a display, 61 (shaded portion) is an infrared image, 41
Is a PPI (abbreviation of Plan Position Indicator, polar coordinate display) image. That is, the infrared image 61 is the PPI image 4
1 and concentric circles, and an infrared image 6
1 and the PPI image 41 have a common (X,
Y) The coordinate configuration is adopted, and the number of pixels in the diameter direction of the circular infrared image 61 is L, and one round of the screen around the center of the screen is 36.
An example corresponding to the azimuth angle (θ) of (A) as 0 degrees is shown.

In the infrared image 61, the stored data 3 of (A)
1 is converted and displayed as an infrared image.
Is the estimated distance within 20 km calculated by the signal processing unit 2
(A circle indicating 10 km is displayed in the middle for the sake of clarity.) Here is an example of displaying the coordinates along with the azimuth.

The data amount of the stored data 31 is 200 × 3
In the case of 0000 = 6M samples, the data amount is uniform in both the horizontal and vertical directions.
Assuming that = 768, the number of pixels in the circular image of the infrared image 61 is (768/2) ² × π- (256) ² × π ≒ 260K
Since the infrared image 61 is only a pixel, and since the infrared image 61 is a circular image, the number of pixels decreases more and more in the direction of the center of the circle (direction in which the high angle decreases in the vertical direction). There is.

Referring again to FIG. 1, the address conversion unit 6 stores the stored data 3 shown in FIG.
1 is read and the coordinate conversion is performed together with the thinning of the sample.

That is, the display rate in the vertical direction (1—thinning rate)
Is represented by N / 200. Here, N is the number of pixels in the vertical direction of the infrared image 61 in FIG.

The display ratio in the horizontal direction (circumferential direction) is Dr (n) / 30,000. However, Dr (n)
= Dv (n) × π, and Dr (n) is the infrared image 61
Is the number of pixels on the circumference of the nth circle from the outermost circumference of
Dv (n) is the number of pixels corresponding to the diameter of the n-th circle from the outermost periphery of the infrared image 61.

Then, based on the display rate in the vertical direction,
The (x, y) coordinate is converted to the (X, Y) coordinate by the following equation.

X = L / 2 + (M + (N−y × N / 200)) sinθ── (3) Y = L / 2− (M + (N−y × N / 200)) cosθ── (4 Here, θ is an azimuth angle, and θ = (x × 360 / 30,00)
0) degrees, L is the number of pixels corresponding to the diameter of the outermost circle of the circular infrared image 61, M is the number of pixels corresponding to the radius of the outermost circle of the PPI image 41, and N is the vertical number of the infrared image 61. The number of pixels in the direction.

Here, x and y are sample numbers of respective axes, and X and Y are pixel numbers of respective axes, and are both positive integers. Accordingly, each of X and Y obtained in the equations (3) and (4) is rounded to obtain one integer value, and there are a plurality of x and y respectively corresponding to the one integer value. In this case, each of X and Y before the rounding uses the sample value of the (x, y) coordinate closest to the one integer value, and the pixel value of the (X, Y) coordinate of the one integer value And

Although the method of simply decimating and using the pixel value of the (X, Y) coordinate has been described above, the average value of the sample values of the plurality of (x, y) coordinates may be used. The maximum value may be adopted.

Then, the obtained pixel values are converted into corresponding X and Y values.
To the scan converter 4 together with the value of

The scan converter 4 accumulates X and Y values corresponding to the pixel values from the address converter 6, and creates an image signal corresponding to the infrared image 61 in FIG. 2B. on the other hand,
The coordinates (x ₁ ,
y ₁₎ from equation (3) and (4) the coordinates corresponding to the target object by (X _1, Y the coordinates of the _{image 1)} to calculate the equivalent to the infrared image 61 (X _1, Y ₁₎ A symbol mark is superimposed on the same coordinate position to create an infrared image signal.

[0059] The signal processing unit coordinates from the x ₁ coordinates of the target information and the estimated distance from the ₂ (X 2, Y 2) said coordinates of the image corresponding to the PPI image 41 to calculate the (X _2, Y
_A PPI image is created by indicating a symbol mark indicating the distance of the target object at the same coordinate position as in ₂ ).

That is, X ₂ and Y ₂ are respectively X ₂ = L / 2 + (M × R / R _max ) sin θ─── (5) Y ₂ = L / 2− (M × R / R _max ) cosθ─── (6) where θ is an azimuth angle, and θ = (x ₁ × 360 / 30,00
0) degrees, L is the number of pixels corresponding to the diameter of the outermost circle of the circular infrared image 61, M is the number of pixels corresponding to the radius of the outermost circle of the PPI image 41, and R is the estimated distance of the target object (K
m) and R _max are distances (20 km in the example of the PPI image 41 in FIG. 2) assigned to the outermost circle of the PPI image.

Here, x is a sample number on the x-axis, and X and Y are pixel numbers on the respective axes, so that both are positive integers. Therefore, X ₂ obtained in the equations (5) and (6)
And Y ₂ are rounded off to get one integer value each.

Then, the infrared image and the PPI image are superimposed, and a television image signal converted into a television scanning display format is transmitted to the display unit 5.

The display section 5 displays the television image signal on a display as a television screen.

FIG. 3 is a structural example showing an embodiment of an infrared detecting apparatus according to the present invention, wherein 1 is an infrared sensor unit, 2 is a signal processing unit, 3 is an all-around image memory unit, 4 is a scan conversion unit, and 5 is a display. , 6 is an address converter, and 11 is an optical system, 12 is an infrared imager, 13 is an AD converter, 14 is a gimbal, 21 is a target extractor, 22 is a target information generator,
23 is a detection S / N calculation unit.

The infrared sensor 1 comprises an optical system 11, an infrared imager 12, an A / D converter 13, and a gimbal 14. The signal processor 2 comprises a target extractor 21, a target information generator 22, a detection S / N. And a calculation unit 23.

In the infrared sensor section 1, the optical system 11 collects the incident infrared light, and the collected infrared light is sent to the infrared image pickup device 12. The infrared image pickup device 12 converts the infrared light into an infrared image signal of an analog electric signal. The analog signal is sent to an AD converter 13, which converts the infrared image signal of the analog electric signal into a digital signal.

On the other hand, the gimbal 14 has three axes of a pitch axis, a roll axis, and a yaw axis having a function of correcting the motion,
The optical system 11, the infrared imager 12, and the AD converter 13 are fixedly installed on a gimbal 14.

Therefore, in the infrared sensor section 1, when the gimbal 14 turns at a speed of, for example, 1 revolution / second, a 360-degree omnidirectional digital infrared image signal is obtained. The angle information (azimuth and height) at the gimbal 14 corresponding to the digital infrared image signal is sent to the target image generation unit 22 and the entire image memory unit 3.

The target extracting unit 21 performs filtering processing for extracting a point-like target, infrared ray intensity calculation processing, and the like on the digital infrared image signal, and moves the target whose point-like infrared reception intensity increases to the target. And detecting the S / N ratio value of the infrared image signal. Then, the measured S / N ratio value corresponding to the detected object is sent to the target information generation unit 22. On the other hand, the detection S / N calculation unit 2
In 3, the distance is calculated from the weather conditions (temperature, humidity, visibility) at the corresponding point in time previously input by the operator and the wavelength band of the infrared rays specific to the infrared sensor unit 1 stored in advance by the above-mentioned atmospheric transmittance calculation model. Calculates the infrared transmittance of the atmosphere for each atmosphere, and assuming the type of the detected object from the situation where the ship on which the infrared detection device of the present invention is mounted is input by the operator. Object target conditions (area,
Speed) and the weather conditions to calculate the infrared radiation intensity,
The detection S / N ratio value corresponding to the distance is obtained by the above equation (2), and the detection S / N ratio value (hereinafter, referred to as detection S / N) is sent to the target information generation unit 22.

The target information generator 22 calculates the measured S
When the / N ratio value (hereinafter referred to as measurement S / N) becomes a certain value or more, it is recognized as a "target object", and this time is defined as a first scan, and scanning is further continued to define the measurement S / N. If it exceeds the value, it is recognized as "a target object that should be a threat". Also,
From the specified number of times of scanning, the converted S / N ratio value (hereinafter referred to as converted S / N) is calculated using the measured S / N and the least squares approximation equation (1). Then, the distance to the target object is estimated by comparing the detection S / N from the detection S / N calculation unit 23 with the converted S / N.

Here, in order to make the process of estimating the distance to the target object easier to understand, a description will be given with reference to FIGS. 4 and 5 and an example of a recognition state of the target object and the like will be described in Table 1.

That is, FIG. 4 is an example of a graph showing the S / N for each scan according to the present invention, and shows the calculated S / N corresponding to the measured S / N for each scan. FIG. 5 is a graph example showing the S / N with respect to the distance according to the present invention.
The discrete S / N calculated by the N calculator 23 is interpolated to indicate the detected S / N as a continuous linear graph, and the same value as the converted S / N for each scan in FIG. 4 is detected in FIG. A search is performed on the S / N, and a corresponding distance is set as a distance (estimated distance) between the target object and the infrared detection device.

Table 1 is a specific example in which the converted S / N and the estimated distance are calculated from the measured S / N. The number of scans, the measured S / N, the converted S / N, and the estimated distance are illustrated in correspondence. I have. Then, when the measurement S / N from the target extraction unit 21 exceeds 5, it is recognized as a “target object” and is set as the first scan count, and from the third scan count, the above equation (1) and ( The converted S / N and the estimated distance calculated in 2) are shown. From the time when the measured S / N exceeds 13, that is, the seventh scanning time, it is recognized as a “target object to be a threat”.

[0074]

[Table 1] In addition, the target information generation unit 22 uses the coordinates (x ₁ , y ₁ ) of the target object corresponding to FIG. 2A based on the direction information (direction and height) from the infrared sensor unit 1 for each scan. Generate.

Then, the coordinates (x ₁ , y
₁ ) and the obtained estimated distance and information on whether or not the target object is the threat are sent to the scan conversion unit 4 as target information.

As described with reference to FIG. 2A, the full-circumference image memory unit 3 uses the digital infrared image signal as data as described above with reference to FIG. Are stored corresponding to the (x, y) coordinates. That is, 30,000 samples corresponding to 360 degrees of the azimuth angle (θ) are stored as horizontal samples corresponding to the x-axis, and based on the azimuth information from the infrared sensor 1, up to the base angle of the high angle plus 2.4 degrees. Accumulates 200 samples corresponding to the y-axis as vertical samples. (FIG. 2A shows an example where the base angle is 0 degrees.) Then, the base angle information is sent to the scan conversion unit 4.

The address conversion unit 6 sequentially reads the stored data 31 of FIG. 2A from the full-circumference image memory unit 3 in correspondence with (x, y), and obtains the data of FIG.
Conversion into (X, Y) coordinates corresponding to the infrared image 61 of FIG. At this time, the conversion from the sample value of the stored data 31 to the pixel value of the infrared image 61 is based on the simple thinning described above. Then, the (X, Y) coordinates and the pixel value corresponding to the (X, Y) coordinates are sent to the scan conversion unit 4.

In the scan conversion unit 4, the entire image memory unit 3
These base angle information are accumulated, and the address conversion unit 6
The X and Y values corresponding to the pixel values are stored, and the infrared image shown in FIG.
An image signal corresponding to the image 61 is created. Meanwhile, signal processing
The coordinates (x₁, Y₁) Formula
The coordinates corresponding to the target object according to (3) and (4)
(X ₁, Y₁) Is calculated and corresponds to the infrared image 61.
The coordinates (X₁, Y₁) At the same coordinate position as
An omnidirectional infrared image signal is created by superimposing the mark.

Further, the coordinates (X ₂ , Y ₂ ) are calculated from the x ₁ coordinate as the target information from the signal processing unit 2 and the estimated distance by the equations (4) and (5), and correspond to the PPI image 41. A symbol mark is superimposed on the same coordinate position as the coordinates (X ₂ , Y ₂ ) of the image to create a PPI image indicating the distance of the target object.

By the way, in FIG. 2B, if L is 768 pixels and the number of pixels corresponding to the radius of the innermost circle of the infrared image 61 is 128 pixels, (x ₁ , y ₁ ) = (1000, 1000)
120), (X ₁ , Y ₁ ) = (448, 84), and the position of the outer circle of the PPI image 41 (Equations (5) and (6))
Of the R _max) and 20 km, the estimated distance is assumed to be 10 km, the _{(X 2, Y 2) =} (411,259).

The omnidirectional infrared image signal and the PP
I image and the bow indicating symbol mark obtained by obtaining the heading information of the ship from another gyro system and transforming the coordinates (L / 2, L / 2) of FIG. Superimposed,
The television image signal converted into the display format of the television scanning system and the base angle information synchronized with the television image signal are transmitted to the display unit 5, and the display unit 5 displays a television screen on a display. . Although not described, the display of the base angle information may be superimposed on the television screen, or may be displayed independently.

FIG. 6 shows a first display example of the present invention,
1 is a PPI image, 42 is a first target distance symbol, 43
Is a second target distance symbol, 44 is a first target distance locus, 45 is a second target distance locus, 61 is an infrared image, 6
2 is a designated direction screen, 63 is a first target symbol, 64 is a second target symbol, and 65 is a ship symbol.

The PPI image 41 and the infrared image 61 are displayed as concentric circles, and the azimuth 0 degree (true north) is always fixed to the front (upward in FIG. 6).
5 indicates the direction of travel (bow direction) of the ship, here 90
Although an example in which the direction of the ship is oriented is shown, this is an example of a true azimuth display in which the direction changes as the traveling direction of the ship changes.

The first target distance symbol 42 and the second target distance symbol 43 are symbol marks indicating the distance between the first target object and the second target object displayed in the PPI image 41, respectively. Yes, first target symbol 63
And the second target symbol 64 are symbol marks representing the first target object and the second target object respectively displayed in the infrared image. Therefore, the orientation of the first target distance symbol 42 and the first target symbol 63 and the orientation of the second target distance symbol 43 and the second target symbol 64 are identical. Then, the first target distance locus 44
And the second target distance trajectory 45 represent the symbols displayed in the past (at the time of scanning earlier than the time point) of the first target distance symbol 42 and the second target distance symbol 43, respectively. ) For convenience, and are not displayed on the actual screen. In addition, each straight line connecting between the symbol marks of the first target object and the symbol marks of the second target object in the PPI image 41 and the infrared image 61 has the same azimuth for convenience. It is not displayed on the actual screen.

The designated azimuth screen 62 is an enlarged view of the vicinity of the first target symbol 63 in the infrared image 61 (range indicated by a dotted line). That is, when a display switching instruction including the azimuth angle is given from the operator to the scan conversion unit 4 and the address conversion unit 6 in FIG. 3, the address conversion unit 6 stores the omnidirectional image memory unit 3 in FIG. The reading of the stored data 31 in the order of (x, y) is stopped, and the scan converter 4 directly outputs the azimuth angle ± 1.6 degrees of the stored data 31 (± 13 degrees on the x-axis).
(3 samples) sequentially read in the range (x, y),
After conversion to the same (X, Y) coordinates as in FIG. 2B without thinning out, the television image signal converted into the display format of the television scanning system is sent to the display unit 5 and displayed on the display unit 5. The specified screen becomes the designated azimuth screen 62.

That is, the azimuth angle is set to θ ₀ in FIG.
Then, the corresponding x-axis x ₀ is x ₀ = 30,000 × (θ ₀ /
360), and in the scan conversion unit 4, x _p = x ₀ −133 to
All the sample values corresponding to the coordinates (x _p , y _p ) of x ₀ +133 and y _p = 1 to 200 (where x _p is an integer and y _p is a positive integer) are sequentially read. However, in practice, when x _p is more than 30,000 or less than 1, it is necessary to read the stored data 31 from the left and right sides, respectively.

[0087] That is, y _p is not converted, when x _p> 30,000 reads the sample value of x _p -30,000 as x _p,
When 1 ≤ x _p ≤ 30,000, read out the sample of x _p
When _p <1 reads the sample value of x _p +30,000 as x _p.

Then, the designated direction screen is displayed on the display 71.
Substantially for display in the center (x _p, y _p) coordinates of the following (7), accumulated after conversion into the (X, Y) coordinates by equation (8), to create the specified orientation screen.

X = x _p −x ₀ + L / 2─── (7) Y = y _p− 100 + L / 2─── (8) Further, the coordinates (x ₁ ) from the signal processing unit 2 with respect to the target object are obtained. , it is determined whether y ₁₎ coincides with the coordinates (x _p, y _p), if there is a match x ₁ and y _1, respectively (7), and x _p in (8) The coordinates (X _P , Y _P ) are calculated by substituting them into y _p , and (X,
Y) The symbol character is superimposed on the same coordinate position as the coordinates (X _P , Y _P ) on the coordinates.

Then, the television image signal converted into the display format of the television scanning system is transmitted to the display unit 5, and the display unit 5 displays the designated azimuth screen 62.

FIG. 7 shows a second display example according to the present invention.
1 is a PPI image, 42 is a first target distance symbol, 43
Is a second target distance symbol, 44 is a first target distance locus, 45 is a second target distance locus, 61 is an infrared image, 6
3 is a first target symbol, 64 is a second target symbol,
65 is a ship symbol.

The PPI image 41 and the infrared image 61 are displayed as concentric circles, the traveling direction (bow direction) of the ship is always fixed to the front (upward in FIG. 7), and the ship symbol 65 is In the example shown here, the heading is directed at 90 degrees. However, when the heading of the ship changes, the PPI image 41 including the azimuth and the infrared image 61 are linked to each other. Is an example of a heading display that changes. That is, the example of the heading display in FIG. 7 is obtained by rotating and converting the example of the true heading display in FIG. 6 by the direction of the ship.

The first target distance symbol 42 and the second target distance symbol 43 are symbol marks indicating the distance of the second target object from the first target object displayed in the PPI image 41, respectively. Yes, first target symbol 63
And the second target symbol 64 are symbol marks representing the first target object and the second target object respectively displayed in the infrared image. Therefore, the azimuths of the first target distance symbol 42 and the first target symbol 63 and the azimuth of the second target distance symbol 43 and the second target symbol 64 respectively match. Then, the first target distance locus 44
And the second target distance trajectory 45 represent the symbols displayed in the past (at the time of scanning earlier than the time point) of the first target distance symbol 42 and the second target distance symbol 43, respectively. ) For convenience, and are not displayed on the actual screen. Further, each straight line connecting between the symbol marks of the first target object and the symbol marks of the second target object in the PPI image 41 and the infrared image 61 has the same orientation for the sake of convenience. It is not displayed on the actual screen.

That is, when the operator instructs the scan conversion unit 4 shown in FIG. 3 to switch the display of the heading direction, the scan conversion unit 4 converts the (X, Y) coordinates with respect to the true direction display of FIG. After the polar coordinate conversion by the azimuth angle (θ _S ) from the gyro system, the television image signal converted to the television scanning display format is transmitted to the display unit 5 and displayed on the display unit 5.

FIG. 8 shows an example of the high-angle information screen of the present invention. The horizontal axis (X-axis) indicates the distance, the vertical axis (Y-axis) indicates the 90-degree direction of the high angle (height), and 81 indicates a 30-degree line. , 82 are 60-degree lines, and 83 is a symbol mark. The 30-degree line 81 and the 60-degree line 82 are auxiliary lines that indicate the target of the high angle, indicate the direction of the high angle 30 ° and the direction of the high angle 60 °, respectively, and indicate the position of the target object (distance and high angle).
Is indicated by a symbol mark 83. Then, X and Y are made to correspond to the number of pixels.
0 km is 200 pixels, and in order to match the actual sense of the high angle with the sense on the high angle information screen, X at the high angle of 45 degrees
The number of pixels on each of the axis and the Y axis is the same. Where X
The display of the axis and the Y axis are shown for convenience of explanation, and are not actually displayed.

That is, in FIG. 3, when the operator instructs the scan conversion unit 4 to switch the display to the high-angle display, the scan conversion unit 4 generates the base angle from the full-circle image memory unit 3 and generates the target information. From the coordinates (x ₁ , y ₁ ) for the target object in the target information from the unit 22 and the estimated distance, the X axis and Y
The position on the axis is calculated, and the symbol mark 83 is superimposed on the position. The high angle, the high angle = base angle +2.4 degrees _{× (1-x 1/200} ) , and the where the distance of the target object 6.5km, a high angle 2
X is 65 (pixels) and Y is 2 (pixels) (= 65 ×
tan2 °), and the symbol mark 83 is superimposed around the position of the coordinates (65, 2).

Here, the 30-degree line 81 and the 60-degree line 82 are previously set to α = 30 ° or 60 °, respectively, and Y = X · tan α
Is a plot of coordinates (X, Y) of the result of increasing X by 1 from 0 in the equation.

Then, the television image signal converted into the display format of the television scanning system is transmitted to the display unit 5 and displayed on the display unit 5.

In this specification, the number of pixels on the screen and FIG.
The number of samples and the range of the high angle in (A) are limited, and two auxiliary lines (the 30-degree line 81 and the 60-degree line 82) in FIG. 8 are limited to the 30-degree and 60-degree directions, respectively. , But not limited to these limitations.

[0100]

As described above, the omnidirectional infrared image is formed on a concentric circle with the PPI image indicating the distance of the target object and displayed as one screen, and a part of the infrared image is enlarged by the display switching instruction. Displaying the designated azimuth screen or the high angle information screen indicating the high angle and the distance of the target object has the effect of displaying the heading / approaching object in a visually easy-to-understand manner.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a memory mapping example of the present invention.

FIG. 3 is a configuration example showing an embodiment of the infrared detection device of the present invention.

FIG. 4 is a graph example showing S / N for each scan according to the present invention.

FIG. 5 is an example of a graph showing S / N against distance according to the present invention.

FIG. 6 is a first display example of the present invention.

FIG. 7 is a second display example of the present invention.

FIG. 8 is an example of a high-angle information screen according to the present invention.

FIG. 9 is a diagram illustrating the principle of a conventional infrared detection device.

FIG. 10 shows a conventional display example of an omnidirectional infrared image and an enlarged display example of an arbitrary azimuth.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Infrared sensor part 2, 2a Signal processing part 3, 3a Full-circle image memory part 4, 4a Scan conversion part 5 Display part 6 Address conversion part 21 Target extraction part 22 Target information generation part 23 Detection S / N calculation part 31 Storage data 41 PPI image 61 Infrared image 62 Specified direction screen

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Takeshi Yanagita 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Prefecture Inside Fujitsu Limited (72) Inventor Takayuki Tsuboi 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa No. 1 Within Fujitsu Limited (72) Inventor Masahiro Nakagawa 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture F-term within Fujitsu Limited (reference) 2G065 AA04 AB02 BA14 BA33 BB49 BC11 BC14 BC28 BC33 BD03 DA20 5J070 AC02 AC13 AE04 AE06 AF05 AH31 AH39 AK39 BG06 5J084 AA05 AA10 AB03 AB05 AC03 BA11 CA26 CA61 CA70

Claims (5)

[Claims] 1. An infrared sensor comprising: infrared sensor means for scanning 360 degrees in all directions to capture an image; and signal processing means for extracting an object headed or approached from an omnidirectional image signal from the infrared sensor means. An omnidirectional image memory means for storing the omnidirectional image signal as omnidirectional image data; and an address converting means for converting the omnidirectional image data into an omnidirectional infrared image signal that can be displayed in a circular shape. Scanning conversion means for superimposing a symbol mark based on the angle information of the object from the signal processing means on the omnidirectional infrared image signal and converting the image signal into a display format; and displaying the image signal converted into the display format. A display method for an infrared detection device, comprising: a display unit. 2. The display method of the infrared detection device according to claim 1, wherein the scan conversion unit is capable of displaying the concentric circle with an omnidirectional infrared image signal on which the symbol mark is superimposed. A scanning conversion unit for generating a PPI image signal with a symbol mark based on distance information of the object from the infrared detection device. 3. The display method of the infrared detection device according to claim 2, wherein the signal processing unit performs a scan corresponding to the object in the omnidirectional image signal every time the infrared sensor unit scans. / N ratio is measured and the S /
Signal processing means for calculating a distance to the object from the N ratio and an S / N ratio of the object calculated based on a previously input weather condition and a target condition assuming the object. The display method of the infrared detection device. 4. The display method of the infrared detection device according to claim 1, wherein the scan conversion unit is configured to separate the object from the signal processing unit separately from the omnidirectional infrared image signal. Scanning conversion means for generating a high-angle information image signal with a symbol mark corresponding to the object based on the distance information and the high-angle information originating from the infrared sensor means, and converting the signal into a display format. Characteristic display method of infrared detector. 5. The display method of the infrared detection device according to claim 1, wherein the scan conversion unit is configured to: display the omnidirectional infrared image signal and the PPI image in response to a display switching instruction including azimuth information. A scanning conversion means for generating an enlarged designated azimuth image signal of a portion corresponding to the azimuth information in the omnidirectional infrared image signal separately from the signal and converting the signal into a display format. Display method of the detection device.