JPS58180918A - Infrared ray monitoring device - Google Patents

Abstract

PURPOSE:To perform infrared ray monitoring characterized by a broad visual field, high detecting probability, and low error detecting probability, by combining vertical scan, horizontal scan, and rotary scan so as to form a desired number of combinations, and receiving incident infrared rays by infrared ray detectors which are arranged in a linear state. CONSTITUTION:Incident infrared rays 5 are inputted into a monitoring optical system comprising a focal optical system 6, a vertical scanner 7, a horizontal scanner 8, a condenser lens 10, infrared ray detectors 9 which are arranged in a linear state, and the like. The monitoring optical system is provided on a rotary mount 11, which is rotated by a rotating device 14. The scanners 7 and 8 and the device 14 are controlled through a signal processing part 12. Vertical scan and rotary scan are performed by the combination of the scanner 7 and the device 14, and horizontal scan is performed only by the scanner 8. In these ways, the monitoring characterized by a broad visual field 1 and a narrow visual field 20 having a high data rate can be performed. As a result, the infrared ray monitoring characterized by the broad vidual field, highe detecting propability, and low error detecting probability can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is characterized in that the field of view of each infrared detector arranged in a 11i line is scanned in a scanning direction as necessary.

The present invention relates to an infrared monitoring device that images a surrounding scene as a thermal image by switching in the direction in which infrared detectors are arranged or in a direction perpendicular to that direction.

FIG. 1 is a diagram illustrating an example of a scene that an infrared monitoring device must image. In the field of view (1), there is a goal (
In addition to 2), the sea surface (3), clouds (4), etc. are included.

In order to accurately detect a target (21 gold) with an infrared monitoring device, infrared radiation emitted from the target (2) and objects other than target (2), such as the sea surface (31, clouds (4), etc. in the example in Figure 1) It is necessary to completely separate target (2) by taking advantage of the differences in the temporal and spatial properties of The apparent position of target (2) remains unchanged, the infrared reception sound from target (2) increases monotonically over time, and the apparent temperature difference with the background is small.

On the other hand, infrared rays emitted from the sea surface (31, true (41, etc.) usually fluctuate temporally and spatially over a wide area. Therefore, the m-image method of infrared monitoring equipment is based on the characteristics of the radiation described above. A convenient way to separate the differences, i.e.
A method with a high temperature resolution and a high data rate, that is, the number of times the same space can be scanned per unit time, is desirable.

The present invention has been made with all the necessary considerations in mind, and the contents thereof will be explained in detail below with reference to the drawings.

FIG. 2 is a diagram showing an embodiment of the invention.

Incident infrared light (5) Afocal optical system that receives all light (61
゜Vertical scanner (7) that scans the scene back and forth in the vertical direction.

A horizontal scanner (8j) that scans the scene back and forth in the horizontal direction.

A condensing lens 00) that condenses infrared light onto the linearly arranged infrared detectors (9) is installed on a rotating pedestal 01). The direction of arrangement is parallel to the scanning direction of the vertical scanner (7).

The signal processing section ■ has infrared detectors (9) arranged in a straight line.
control open signal aalt-output based on each output]7. It controls the operations of the vertical scanner (7), the horizontal scanner +81, and the rotary gantry swivel device (141).The device shown in FIG. Scanning is performed in two modes: a serial mode in which the horizontal scanner (8) is activated and the horizontal scanner (81) is not activated, and a parallel mode in which only the horizontal scanner (81) is activated. These two modes will be described below.

FIG. 3 is a diagram showing the serial mode. In the serial mode, the combination of reciprocating scanning of the vertical scanner and horizontal scanning, which is sufficiently slow compared to the scanning of the vertical scanner with a single rotation mount, allows the scanning direction to be moved in a straight line as shown in the figure. Since it takes the form of moving horizontally in a zigzag pattern, which is almost the same as the direction of the array of infrared detectors (9),
Although the period of scanning the same space is long, a large horizontal field of view (for example, all around) can be obtained. Further, the infrared detectors (9) arranged in a straight line are used for scanning by a vertical scanner.

In order to view the space of 10"- in sequence, if the output signal sound of each detector is delayed by an appropriate time and added, a signal with excellent temperature resolution can be obtained. TDI (T 1m5
This is a well-known technique among experts as a delay and integration method. In serial mode.

The output of each detector is input to the signal processing circuit αη after passing through a TDI circuit provided in the signal processing unit for performing TDI.

FIG. 4 is a diagram showing the parallel mode. In the parallel mode, only horizontal reciprocating scanning is performed by the horizontal scanner, so the scanning direction α5) is in line with the row of infrared detectors, and the infrared i detectors (9) arranged in a straight line are arranged in a straight line. Although the spaces viewed by the robots are independent, the same space can be scanned many times in a relatively short period of time because the horizontal scanner performs back-and-forth scanning. However, the field of view is narrower than in the serial mode because it is determined by the length of the infrared detector array in the vertical direction and by the field of view of the horizontal scanner in the horizontal direction.

In addition, in FIG. 4, the output of each detector is output from an MPX (Mult
Although the MPX circuit is configured to be converted into a single signal by the ipl *

FIG. 5 is a diagram showing switching of scanning modes in the infrared monitoring device according to the present invention.

As mentioned above, the infrared monitoring device according to the present invention has good temperature resolution and a wide field of view.

Scenes can be scanned by switching between two modes: the serial mode, which has a low data rate (that is, the number of times the same space is scanned per hour), and the parallel mode, which has a high data rate but is inferior to the serial mode in both temperature resolution and field of view. First, in serial mode, a wide field of view (1) is searched with good temperature resolution, and if point α9, which is suspected to be the target in terms of temperature change and size, is detected as a friend, then the surrounding area (a) is searched in parallel mode. By scanning the target and analyzing the temporal variations in infrared radiation from the suspected point, it is possible to distinguish whether it is a real target or not. Therefore.

Since the infrared monitoring device according to the present invention has a dual target identification function, it is possible to obtain a high detection probability and a low false alarm probability. Note that the above-mentioned detection of points suspected to be targets and analysis of temporal fluctuations in infrared radiation from points suspected to be targets are automatically performed in the signal processing unit shown in Figure 2, but these techniques is extremely easy to do using recent digital signal processing technology t4.

As described above, the infrared monitoring device according to the present invention can have a wide field of view, a high detection probability, and a low false alarm probability by switching between the two scanning methods.

Although the above description has been made regarding an infrared monitoring device using an infrared detector as a photodetector, the present invention is not limited to this, but can also be applied to an optical monitoring device using a visible light photodetector such as a CCD.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of a scene that must be imaged by an infrared monitoring device, FIG. 182 is a diagram showing an embodiment of the present invention, and FIG. 3 is a diagram showing a serial mode. FIG. 4 is a diagram showing the parallel mode, and FIG. 5 is a diagram showing switching of the scanning mode in the infrared monitoring device according to the present invention. In the figure, (7) is a vertical scanner, (81 is a horizontal scanner), (9) is an infrared detector arranged in a straight line, (1υ is a rotating mount, (121 is a signal processing unit, and (121 is a scanning direction) In Figure 0, the same or equivalent parts are indicated by the same reference numerals. Agent Shin Kuzuno -

Claims (1)

[Claims] An afocal optical system that receives incident infrared light. A vertical scanner that scans the infrared light emitted from the afocal optical system back and forth, a horizontal scanner that scans the infrared light back and forth in a direction perpendicular to the fixed direction of the vertical scanner, a condensing lens that focuses the infrared light, and Togen. an infrared detector of f and Mfl provided on the imaging plane of the lens and arranged in the same direction as the direction in which the vertical scanner travels; and a pedestal for holding all of the above-mentioned parts. A rotating device that rotates and scans the mount in the same direction as the scanning direction of the horizontal scanner, The patented line sighting device is fully equipped with a signal processing section that generates a signal to operate in a predetermined combination with the turning Atfit'.