JPH06342051A - Image-sensing and tracking apparatus - Google Patents

Abstract

PURPOSE:To obtain an image-sensing and tracking apparatus which is provided with a photodetector which can read out a signal at high speed even when the number of pixels is many and with a tracking and processing circuit which is operated at high speed. CONSTITUTION:This apparatus is constituted in such a way that the readout region of a photodetector is divided into three regions, that HCCD (horizontal- direction two-dimensional interlinear charge-coupled devices) and FDA(floating diffusion amplifiers) are installed respectively and that signals in the three regions perform a simultaneously parallel readout operation. In addition, the apparatus is constituted in such a way that a mode judgment part 23 which uses a selection circuit as a constituent element is installed in a tracking and processing circuit 6, that, when the image of a target is tracked, an output from the divided region in the center of the photodetector 1 is input directly to a binary-coding and processing part 9 by the mode judgment part 23 and that a tracking and processing operation is performed only within the image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state imaging device having an image tracking function, that is, a so-called imaging tracking device.

[0002]

2. Description of the Related Art FIG. 3 is a diagram showing an example of a conventional infrared imaging and tracking device, in which 1 is a photodetector, 2 is a gimbal, and 3 is a gimbal.
Is a gimbal drive mechanism, 4 is a preamplifier, 5 is analog /
Digital converter (hereinafter referred to as A / D converter), 6 is a tracking processing circuit, 7 is a frame memory, 8 is a processed image selector, 9 is a binarization processing unit, 10 is a significant target determination unit, 11 is a video digital / An analog converter (hereinafter referred to as a D / A converter) 12 is a display monitor.

FIG. 4 shows a two-dimensional interline charge-coupled device (Char) used in a conventional infrared imaging and tracking device.
FIG. 1 is a schematic diagram of an array photodetector (ge coupled device: hereinafter referred to as CCD), in which 13 is a light receiving region and 14 is a transfer gate (Transfer Gate:
Hereinafter referred to as TG) Control scanner, 15 is a horizontal C
Reference numeral 16 denotes a CD (hereinafter referred to as HCCD) and 16 denotes a floating diffusion amplifier (hereinafter referred to as FDA).

The photodetector in the conventional image pickup and tracking device is constructed as described above, and the signal charges in one stage of the light receiving area 13 selected by the TG scanner 14 are transferred to the HCCD 15 by the vertical CCD in the light receiving area 13. , Then C
It is read as a time series signal from the FDA 16 by the CD operation. For example, using a photo detector of 512 × 512 pixels,
When imaging with the NTSC system, the clock (hereinafter referred to as CLK) frequency for reading the signal charge is about 9M.
Hz and the frame rate is 30 Hz.

Next, a pixel tracking circuit in the infrared imaging tracking device will be described with reference to FIG. When searching for a target, the photodetector 1 searches while changing the field of view by the movement of the gimbal. The output analog data signal of 512 × 512 pixels is amplified by the preamplifier 4 and then A / D
It is converted into a digital signal by the converter 5 and stored in the frame memory 7. Thereafter, the processed image selector 8 sequentially cuts out data of, for example, 256 × 256 pixels, the binarization processing unit 9 converts the data into binary image elements, and the significant target determination unit 10 selects a target to be tracked. . When the target is captured, the gimbal 2 is operated and the target is drawn so that the target is in the center of the field of view, and the tracking loop is entered. At the time of image tracking, the target is already drawn near the center of the field of view, and it is not always necessary to process all image data from the viewpoint of high-speed processing. Therefore, the processed image selector 8 always displays, for example, 256 × near the center of the visual field.
Data of 256 pixels is cut out, binarization processing is performed on the data, and after the target to be tracked is selected by the significant target determination unit 10, tracking processing is performed based on the sequence of the system.

[0006]

The conventional image pickup and tracking device is configured as described above. However, when this device is used for high speed image tracking such as a missile, a high frame rate of about 60 Hz is required. It is necessary, and the read CLK in this case is about 18 MHz. However, for example, most of the devices for the purpose of imaging and tracking by infrared rays need to cool the photodetector to a low temperature of about 80K,
In this case, the read CLK frequency is limited to about 9 MHz in terms of the transfer efficiency of the element and other aspects. Therefore, in this type of application, a photodetector with a small number of pixels has to be used, which is unsatisfactory in terms of search range or image resolution.

Further, since the conventional image tracking processing circuit is configured as described above and requires the frame memory for the display image and the processing image selector for cutting out the image, the tracking processing takes time accordingly. Was there.

The present invention has been made in order to solve such a problem, and has a photodetector capable of reading a signal at high speed even if the number of pixels is large, and operates faster than before. An object is to provide an imaging and tracking device having an image tracking processing circuit.

[0009]

In the photodetector of the image pickup and tracking device according to the present invention, the readout area is divided into three areas, and HCCD and FDA are provided in each area, and signals in the three areas are read out in parallel at the same time. It was done so.

Further, the tracking processing circuit of the image pickup and tracking device according to the present invention is provided with a mode determination section having a selection circuit as a constituent element before and after the frame memory, and the operation can be switched by the selection circuit at the time of searching for a target and at the time of tracking. It was done like this.

[0011]

In the present invention, the image signal of the photodetector is 3
It is divided into areas and each is read out in parallel at the same time.
The read signals of the three areas are simultaneously input to the tracking processing circuit in parallel, and at the same time, converted into a serial signal by the screen synthesis unit and displayed on the monitor.

When moving from target search to target tracking,
Only the data output from the central reading area of the photodetector by the mode determination unit added to the tracking processing circuit is directly input to the binarization processing unit.

[0013]

【Example】

Example 1. FIG. 1 is a diagram showing a configuration of an infrared imaging and tracking device showing an embodiment of the present invention, in which 17 is a first preamplifier for receiving a signal from a first divided area of a photodetector, and 1
8 is a second receiving signal from the second divided area of the photodetector
Preamplifier, 19 is a third preamplifier that receives a signal from the third divided region of the photodetector, 20 is a first A / D converter, 21 is a second A / D converter, and 22 is a third
A / D converter, 23 is a mode determination unit, and 24 is a first
Is a changeover switch, 25 is a second changeover switch, 26 is a third changeover switch, 27 is a fourth changeover switch, and 28 is a screen compositing unit.

FIG. 2 is a schematic diagram of a photodetector of an infrared imaging and tracking device showing one embodiment of the present invention, in which 29 is a first divided area, 30 is a second divided area, and 31 is a third divided area. Divided area, 32 is the first HCCD, 33 is the second HCCD, 3
4 is the third HCCD, 35 is the first FDA, 36 is the second
FDA, 37 is the third FDA.

Next, the operation of the photodetector in the first embodiment will be described with reference to FIGS. The respective photodetector areas 29 to 31 having the dedicated HCCDs 32 to 34 and the FDAs 35 to 37 respectively perform the reading operation simultaneously in parallel. For example, when a 512 × 512 pixel photodetector is used, CL that reads out signal charges even when the frame rate is 60 Hz
The K frequency can be suppressed to about 6 MHz. The signal charges of the three areas thus read are input to the tracking processing circuit 6 in parallel at the same time, and at the same time, converted into a serial signal by the screen synthesizing unit 28 and converted into an image signal by the video D / A converter 11 to become a monitor 12. Is displayed in.

Next, the operation of the tracking processing circuit in the first embodiment will be described with reference to FIG. When searching for a target, the mode determination unit 23 closes the first changeover switch 24 and the third changeover switch 26, and the second changeover switch 25.
And the fourth changeover switch 27 is connected to the contact b. At this time, the divided signals from the photodetector 1 are simultaneously stored in the frame memory 7 in parallel. And the processed image selector 8
Cuts out an image for each of the three divided areas from the frame memory 7 and sends it to the binarization processing unit 9. At this time, since the divided areas of the photodetector 1 and the cutout image input to the binarization processing unit 9 match, even if there is a difference in characteristics (transfer efficiency, FDA output characteristics, etc.) between the divided areas. It does not appear on the cutout image. Therefore, the uneven brightness in the screen, which causes an erroneous determination during the binarization process, does not occur. Further, when the target is captured and the tracking process is performed, the gimbal 2 is first moved to draw the target to the center of the screen. Furthermore, the mode determination unit 2
3, the first changeover switch 24 and the third changeover switch 26 are opened, and the second changeover switch 25 and the fourth changeover switch 25 are opened.
The changeover switch 27 is connected to the contact a. That is, only the signal output from the second divided area 30 in the photodetector 1 is directly input to the binarization processing unit 9, and the tracking processing is performed only in that image area. At this time, since the image signal does not require the operation of the frame memory 7 or the processed image selector 8,
Therefore, high-speed tracking processing becomes possible. Also in this case, since the second divided area 30 of the photodetector 1 and the cutout image input to the binarization processing unit 9 match, the characteristic difference between the divided areas causes no problem in the tracking processing. Do not give.

In the above embodiment, CC is used for vertical transfer.
Although a CCD is used for D and horizontal transfer, similar effects can be obtained as long as charge can be read out, such as a MOS switch system. Further, although the above-described embodiment has been described only for the infrared image pickup device, it is obvious that it can be diverted to a general solid-state image pickup device such as a visible camera, and the same effect as that of the above-described embodiment is obtained.

[0018]

As described above, according to the present invention, the reading area of the photodetector is divided into three areas and the reading operations are performed in parallel at the same time. Even if there is, high-speed reading operation is possible.

Further, when an image of a target is tracked, the output from the divided area at the center of the photodetector is directly input to the binarization processing section by the mode determination section, and the tracking processing is performed only within the image. High-speed processing that does not require writing to or reading from the frame memory is possible. Moreover, since the characteristic difference for each divided region does not affect the tracking process at all, erroneous determination in the tracking process due to the division of the light receiving region does not occur.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an infrared imaging and tracking device showing an embodiment of the present invention.

FIG. 2 is a schematic diagram of a photodetector of an infrared imaging tracking device showing an embodiment of the present invention.

FIG. 3 is a diagram showing an example of a conventional infrared imaging and tracking device.

FIG. 4 is a schematic view of a two-dimensional interline CCD array photodetector used in a conventional infrared imaging tracking device or the like.

[Explanation of symbols]

1 Photodetector 2 Gimbal 3 Gimbal drive mechanism 4 Preamplifier 5 A / D converter 6 Tracking processing circuit 7 Frame memory 8 Processed image selector 9 Binarization processing unit 10 Significant target determination unit 11 Video D / A converter 12 Display monitor 13 Light reception Area 14 TG scanner 15 Horizontal CCD (HCCD) 16 Floating diffusion amplifier (FD)
A) 17 1st preamplifier 18 2nd preamplifier 19 3rd preamplifier 20 1st A / D converter 21 2nd A / D converter 22 3rd A / D converter 23 Mode determination part 24 1st switching Switch 25 Second changeover switch 26 Third changeover switch 27 Fourth changeover switch 28 Screen combining section 29 First divided area 30 Second divided area 31 Third divided area 32 First HCCD 33 Second HCCD 34 Third HCCD 35 First FDA 36 Second FDA 37 Third FDA

Claims (2)

[Claims] 1. A solid-state imaging device having an image tracking function, wherein a light-receiving area divided into a first area, a second area, and a third area, and the first, second, and third areas, respectively. Correspondingly provided first horizontal reading circuit, second horizontal reading circuit, third horizontal reading circuit, first signal output circuit, second signal output circuit, and third signal output An imaging and tracking device comprising: a circuit; and a photodetector having a scanner circuit for simultaneously driving the first, second, and third regions in parallel. 2. A mode determination unit for switching operation between a target search and a target tracking, a frame memory for storing an image signal, a processed image selector for controlling reading and writing addresses of the frame memory, and an input. 2. A tracking processing circuit having a binarization processing unit for binarizing the captured image, and a significant target determination unit for selecting a target and generating a tracking signal from the binarized image. Imaging tracking device.