JPH0424590A - Identification device for moving object - Google Patents

Abstract

PURPOSE:To obtain an identification device by which relative positions to surrounding landscape can be correctly caught, by providing an infrared radiation source, an optical filter and a driving part which regulates incident angle of infrared radiation into the optical filter. CONSTITUTION:From an infrared radiation source 2 which is attached to a moving object 1 walking or running on a road, near infrared ray is radiated. A radiation receiving part 3 is positioned at a space, receives the near infrared radiation as well as optical informations by visible radiation regarding surrounding landscape, simultaneously. An optical filter 4 of visible radiation for regulating the near infrared radiation and transmissivity, is provided in front of a CCD camera 7. Since the transmissivity of visible radiation is regulated by regulating incident angle into the filter 4, a ratio of the infrared radiation to the visible radiation can be changed in sequence. An output from the filter 4 is transferred to the CCD camera 7 after converted to electrical signals. Regarding the transferred signals being output from the camera 7, a level ratio of the infrared radiation to the visible radiation can be magnified extremely and therewith contrast of displayed image on a monitor 9 is shown very clearly and therefore the infrared radiation can be easily detected and moving object 1 is identified very clearly, too.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention receives both infrared rays emitted from an infrared light source attached to a moving body on the ground and visible light reflected from natural light, and displays the moving body from a displayed image. The present invention relates to a mobile object identification device for identifying a mobile object, and in particular to an improvement in the ability to identify a mobile object.

[Prior Art] FIG. 6 is a block diagram of a conventional mobile object identification device.
9 is a moving object that walks or runs on a road, 1 is a light receiving section that receives infrared rays and visible light, 6 is an optical lens, 7 is a CCD camera consisting of a photoelectric converter for the received light signal and a scanning circuit that transfers the converted signal, 9 13 is an infrared light source mounted on the moving body 1 and emits infrared rays; and 14 is an aperture mechanism that adjusts the amount of light input to the light receiving section. .

The conventional moving object identification device is configured as described above, and the infrared light source 13 attached to the moving object 1 walking or running on the road emits infrared rays toward the upper space. For example, the infrared rays are received by a light receiving unit mounted on a helicopter or the like. At this time, visible light related to the surrounding scenery due to natural light is also received at the same time. An optical lens 6 is connected to an aperture mechanism 14 that controls the amount of transmitted light by adjusting the aperture area for the input from the light receiving section.
The receiving level of both infrared rays and visible light is adjusted and applied to the CCD camera 7.

FIG. 7 shows an example of the light reception level of the aperture mechanism output, and the infrared rays for identifying the moving object 1 and the visible light for the surrounding scenery are output with approximately the same amount of level adjustment. The CCD camera 7, which is composed of a photoelectric conversion section and a scanning circuit, has an aperture mechanism 1.
The infrared rays and visible light adjusted in step 4 are added, and depending on the level, are converted into electrical signals via photodiodes and the like, and sequentially transferred by a scanning circuit.

Therefore, the infrared rays emitted from the moving object 1 are superimposed and displayed on the monitor 9 using a monitor TV or the like together with the surrounding scenery, and the moving object 1 is identified from the displayed image.

[Problems to be Solved by the Invention] In the conventional moving object identification device as described above, the light receiving sensitivity of both the infrared and visible light input to the light receiving section is adjusted by the aperture mechanism 14, and the scenery is adjusted to a predetermined brightness. The image is displayed on the monitor 9 after being adjusted to the desired angle, but at the same time, the level of infrared rays received from the moving body 1 is also adjusted in the same way, so there is no noticeable difference in the contrast between the infrared rays and the scenery.

Therefore, infrared rays cannot be easily detected from the gray-scale display image on the monitor 9. In particular, when the image is displayed in black and white, detection of infrared rays becomes even more difficult.

Since infrared rays cannot be easily detected from the image displayed on the monitor 9, the moving object 1 cannot be identified at all times, and therefore the moving route cannot be accurately grasped.

This invention was made to solve such problems, and the contrast between the moving object 1 and the scenery on the displayed image can be adjusted to a predetermined ratio, so that the moving object 1 can always be reliably identified and the surrounding scenery An object of the present invention is to obtain a moving object identification device that can accurately grasp the relative position of a moving object.

[Means for Solving the Problems] A mobile object identification device according to the present invention includes an infrared light source that is attached to a mobile object and radiates infrared rays as either a continuous signal or a code modulation signal over a wide spatial coverage area. , an optical filter disposed in front of the CCD camera that transmits infrared rays at a predetermined angle of incidence, blocks visible light, and partially transmits visible light when the angle of incidence is changed, and the angle of incidence of infrared rays on the optical filter. The drive unit is equipped with a drive unit that adjusts the

[Function] In this invention, near-infrared rays are used as an infrared light source,
An optical filter that transmits infrared rays and whose visible light transmittance changes depending on the angle of incidence is arranged at the input of the light receiving section, and the incident angle of the optical filter is controlled by the driving section, and the infrared rays of adjacent wavelengths output from the optical filter are The ratio of the received light level between visible light and visible light can be adjusted.

The infrared rays and visible light received at different levels are photoelectrically converted into electrical signals by the CCD camera, and by the operation of the scanning circuit, the ambient infrared rays and visible rays are detected at levels according to the ratio adjusted by the incident angle of the optical filter. A landscape signal of 1 is output from the CCD camera. When the signal from a CCD camera is displayed as an image on a display, the signal level of infrared rays is significantly higher than that of visible light, so even if the signal is in black and white,
It can be clearly identified even in a dim display.

In addition, under bright natural light, the sensitivity of the entire light receiving section is controlled by the aperture mechanism of the lens system, so the sensitivity to infrared light also decreases, but in this invention, only the sensitivity to natural light is reduced by using an optical filter. Because it is controlled
Maximum sensitivity can be achieved for infrared rays.

Furthermore, if the output of the COD camera is converted into a color signal and applied to a color monitor, only the infrared rays will become a color signal and the scenery will be displayed in black and white, so that moving objects can be identified more reliably. Therefore, moving objects walking or running can be clearly identified at all times, and walking or running routes can be accurately grasped.

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

FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, 1.3.6.7.9 are the same as the conventional device;
2 is an infrared light source mounted on the moving body 1 and emits infrared rays into space; 4 is an optical filter formed by forming a thin film on a glass substrate and whose transmittance changes depending on the incident angle of visible light; 5 is an incident angle of the optical filter 4; 8 indicates a pseudo color display circuit that converts an infrared signal into a color signal.

In the moving object identification device configured as described above, an infrared light source 2 attached to, for example, a human body or a vehicle as a moving object 1 walking or running on a passage uses, for example, an infrared laser to identify a vehicle with a wide upper space. It emits near-infrared rays (wavelength 0.75-2.53rn) with a wavelength adjacent to visible light (wavelength 390-750nm). The near-infrared rays and the transmittance are adjusted at the input of the light-receiving section, that is, in front of the CCD camera 7. An optical filter 4 for visible light is provided.

FIG. 2 shows an example of optical filter spectral characteristics, and 4.5.
6.7 is the same as the above embodiment, and when an interference filter, that is, an optical mirror that transmits light of a predetermined wavelength and reflects light of other wavelengths is used as the optical filter 4, it transmits infrared rays and reflects visible light. The transmittance is adjusted by the angle of incidence between the normal direction of the optical filter 4 and visible light.

■ is infrared incident light, ■ is visible incident light, ■ is infrared transmitted light, ■
indicates the visible reflected light, and θ indicates the angle of incidence between the normal direction of the optical filter 4 and the incident light, and the parallel incident infrared incident light ■ and the visible incident light ■ are controlled by the drive unit 5 to adjust the incident angle θ. When applied to the optical filter 4 having an angle of =45°, the near-infrared light becomes infrared transmitted light (2) with a transmittance of 90%, and most of the visible light is reflected by the optical filter 4 and becomes visible reflected light (2), which cannot be transmitted. The transmitted light passes through an optical lens 6 and is received by a CCD camera 7.

FIG. 3 shows another example of the optical filter spectral characteristics, and 4.
5.6.7, ■, ■, ■, ■, and θ are the same as in the above example, and ■ indicates visible transmitted light that passes through the optical filter 4. Parallel incident infrared incident light ■ and visible incident light ■ is added,
When the incident angle of the filter 4, whose incident angle is changed continuously or stepwise by the drive unit 5, is adjusted to 45 degrees by θ, the infrared transmitted light ■ is transmitted from the optical filter 4 in the same manner as above, and part of the visible light is is transmitted as visible transmitted light ■.

Figure 4 shows an example of the frequency characteristics of an optical filter. At an incident angle of 45°, near-infrared light is adjacent in wavelength to visible light, so near-infrared light is transmitted from optical filter 4 with a transmittance of 90%. Visible light having a wavelength near the cutoff range of the light and filter is output as visible transmitted light (2) with a transmittance of 10 to 20%.

At the incident angle θ=45°, almost no visible transmitted light (3) is output.

When the incident angle θ of the optical filter 4 is controlled in five stages, for example from Oo to 45°, by the drive unit, the transmittance of visible light is adjusted, so the ratio of infrared rays and visible light can be successively changed. .

FIG. 5 shows an example of the optical filter output, in which a certain level of infrared rays output from the optical filter 4 and the optical filter 4
Visible light that depends on the transmittance of is output at a predetermined ratio.

The outputs of the filter 4 are both applied to a CCD camera 7 equipped with an optical conversion section that converts into an electrical signal according to the received light level and a scanning circuit for transferring the electrical signal.

The transfer signal output from the CCD camera 7 has a significantly higher level ratio between the J external line and the visible light, so the monitor 9
When the displayed image is displayed in black and white, the contrast of the image is markedly y, so that infrared rays can be easily detected, and the infrared light source 2, that is, the moving object 1 can be clearly identified.

Furthermore, when the transmittance of visible light is adjusted by changing the incident angle of the optical filter 64 under control from the drive unit 5, the scenery is displayed with appropriate brightness, and the identification of the moving object 1q can be performed more clearly and always reliably. Thus, the moving route 4 of the moving body 1 such as a human body or a vehicle can be accurately grasped.

When the output of the CCD camera 7 is applied to the color display monitor 9 via the pseudo-color display 8, the scenery is displayed in black and white as described above, but the infrared radiation is displayed in a predetermined color, for example, red. identification becomes more reliable.

In addition to continuous radiation, the infrared laser beam emitted from the infrared light source 2 is a code-modulated intermittent signal that operates at 1-second or 2-second intervals, making identification of the moving object 1 even more reliable. I can do it.

[Effects of the Invention] As explained above, this invention uses an optical filter that uses near-infrared rays as infrared rays and adjusts the ratio of the reception level of infrared rays and visible light by changing the transmittance of visible light, and the incident angle of the optical filter. With a simple structure that includes a control drive unit, the ratio of the reception levels of infrared and visible light, which have adjacent wavelengths, can be adjusted, which increases the contrast on the displayed image and allows the device to be used at maximum sensitivity by opening the aperture. Moving objects can be reliably identified at all times.

Since the moving object is displayed superimposed on the surrounding scenery, its position and movement route can be quickly and accurately grasped.

The use of code-modulated infrared rays has the effect that mobile objects can be identified even more reliably.

[Brief Description of the Drawings] Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is an example of the spectral characteristics of an optical filter, Fig. 3 is another example of the spectral characteristics of the optical filter, and Fig. 4 is a block diagram showing an embodiment of the present invention. An example of the frequency characteristics of an optical filter, FIG. 5 is an example of the output of the optical filter, FIG. 6 is a block diagram of a conventional moving object identification device, and FIG. 7 is an example of the light reception level of the light adjustment device output. In the figure, 1 is a moving body, 2 is an infrared light source, 1 is a light receiving section, 4 is an optical filter, 5 is a drive section, 6 is an optical lens, and 7
is a CCD camera, and θ is the incident angle. Note that the same reference numerals in each figure indicate the same or corresponding parts. Patent applicant Tokyo Keiki Co., Ltd. Patent applicant
Technoport Co., Ltd. Fig. 1 Fig. 2 Object/Animal Red 9rm Original light receiving section Optical filter Waist β Kura Rikina 8 Optical reflex CCD camera Entry angle Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 →' S length

Claims (3)

[Claims] (1) A mobile object identification device that uses a CCD camera to receive infrared rays emitted from a moving object on the ground and visible light reflected from natural light to identify a moving object on an image displayed on a display. An infrared light source that is mounted and emits infrared rays as either a continuous signal or a code modulated signal over a wide coverage area of space, and an infrared light source that transmits infrared rays at a predetermined angle of incidence and blocks visible light, and that changes the visible light when the angle of incidence is changed. The present invention includes an optical filter disposed in front of the CCD camera through which a portion of the infrared rays is transmitted, and a drive unit that adjusts the angle of incidence of infrared rays on the optical filter, so that the ratio of the reception level of infrared rays and visible light can be adjusted. Characteristic mobile object identification device. (2) The mobile object identification device according to claim 1, wherein the infrared rays are near infrared rays. (3) The moving object identification device according to claim 1, wherein the optical filter is an optical mirror that transmits or reflects light of a specific wavelength.