JPS63216180A - Image pickup device - Google Patents

Abstract

PURPOSE:To attain high resolution and high-speed image pickup by rotating a linear light sensor around the optical axis of an image pickup lens to obtain a 2-dimensional visual field. CONSTITUTION:A detection head 10 formed by incorporating a linear optical sensor 3b and an image pickup lens 2 is rotated by psi-degrees for N times by a scanning circuit 5 and a moving device 4 at each end of electric scanning of the linear light sensor 3b. The operation is repeated till the relation of psi.N=180 deg. exists to pick up the circular 2-dimensional visual field 1 on an object face and the output of the light sensor 3b obtained by the turning scanning is inputted to a processing section 8, where it is processed. Thus, the 2-dimensional visual field is obtained without being affected by its image pick up range and the image pickup device with high resolution and high speed is obtained.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an imaging device and a device for recognizing the shape and characteristics of an object by processing a video signal obtained by imaging the object. It is something.

[Conventional technology]

(Axes in Figure 3) (b) and (c) are, for example, Ichiko Communication Society Journal (Vol.

64, No. 4) is a configuration diagram showing an imaging system of the conventional imaging device shown in No. 64, No. 4). In the figure, (1) indicates the field of view that indicates the imaging range of the target object, (21 indicates the imaging lens that captures the image within the field of view, and (3a), (3b, and 3c) indicate the imaging plane of the imaging lens (21). The optical sensor placed, arrows (7) and (a) indicate the movement (rotation) direction of the imaging lens (2). Fig. 4 is a block diagram showing the signal processing system of the conventional device, and (4) A moving groove for moving the imaging lens (2), (
5) is a scanning circuit that sends a drive signal for the optical sensor (3) and the moving mechanism (4) and a synchronization signal to the processing unit (8);
6) is an image memory circuit that stores the output of the optical sensor (3) in accordance with scanning, and (7) is a signal processing circuit made of conventional technology.
7) constitutes a processing section (8).

Next, the operation will be explained. Figure 3(a) shows the optical sensor (
3a) shows a method of imaging a two-dimensional target object using an object with a single light-receiving surface. A scan corresponding to can be performed, and in the same way, the arrow (a)
Scanning in the y direction can be performed on the field of view by rotational movement in the direction.

For example, the necessary two-dimensional field of view (1) can be obtained by moving a certain amount in the y direction every time a scan in the x direction is completed.

Further, FIG. 3(b) shows a method for obtaining a two-dimensional field of view using a one-dimensional optical sensor in which a plurality of light receiving elements are arranged in a straight line as an optical sensor (3b). In this case, it is sufficient to electrically scan the optical sensor (3b) in one direction (the y direction in the figure), and move the imaging lens (2) along the arrow (
A two-dimensional field of view (1) can be obtained by rotationally moving in the direction 7).

The method shown in FIG. 3(C) uses a two-dimensional optical sensor in which a plurality of optical sensors are two-dimensionally arranged as the optical sensor (3c). In this method, a two-dimensional field of view (1) corresponding to the shape of the optical sensor (3c) can be obtained only by Gossian scanning of the optical sensor.

In each of the above systems, the imaging lens (2) is driven by a moving mechanism (4) shown in FIG.
A scanning circuit (5) generates a scanning signal necessary for controlling the scanning circuit (5). Further, the scanning circuit (5) supplies scanning signals to the optical sensors (3b) and (3c) that require electrical scanning, and also outputs a synchronization signal to the processing section (8). The processing unit (8) processes the signals obtained by imaging according to the purpose and outputs the processed signals. For example, as shown in the figure, an image memory circuit (6) stores the output of the optical sensor (3) using a synchronization signal from a scanning circuit (5).
), etc., and performs recognition of the shape and characteristics of the target object.

[Problem that the invention seeks to solve]

Conventional imaging devices are configured as described above, so for applications where it is desired to image an object at high speed and high resolution, a system using a single light receiving surface optical sensor (3a) is not suitable for two-dimensional (
(two-axis) movement mechanism is complicated, scanning time is slow and expensive. Furthermore, in a method using a two-dimensional optical sensor (3c), the resolution is determined by the number of sensors, and the current optical sensor molding technology can only achieve a resolution of about 1000×1000. The method using the -dimensional optical sensor (3b) has intermediate properties between the above two methods, and the -dimensional optical sensor (3b) can easily obtain about 4000 elements with the existing technology, and the moving mechanism (4 ) also needs only the − dimension (− axis),
It can be said to be the most promising method among conventional imaging devices because it can also speed up the scanning time. However, in this method, it is necessary to improve the scanning accuracy of the moving mechanism (4) as the distance between the target object and the imaging device becomes longer, and there are problems such as the device becomes complicated and expensive.

That is, as shown in FIG. 5, the resolution l on the target visual field (11) is determined by the imaging lens (
The rotation angle θ of 2), the target field of view (1), and the imaging lens (21
Determined by distance.

It is obtained as 1=L-tanθ·(1).

Therefore, when high resolution and long imaging distance are required, the value of θ becomes small, the structure of the moving mechanism (4) becomes complicated, and the cost of the device increases accordingly.

This invention was made to solve the above-mentioned problems, and it is an object of the present invention to provide a high-resolution, inexpensive imaging device that can obtain a two-dimensional field of view without being affected by the imaging distance.

[Means for solving problems]

An imaging device according to the present invention includes an imaging lens that images an object, a one-dimensional optical sensor in which a plurality of light receiving elements are arranged linearly on an imaging plane of the imaging lens, and an optical axis of the imaging lens. A moving mechanism that rotates around the optical sensor, a scanning circuit that drives the optical sensor and the moving mechanism, and a processing unit that processes the output of the optical sensor and the signal of the scanning circuit to create a signal that recognizes the target. It is something.

[Effect]

In the imaging device according to the present invention, since the -dimensional optical sensor is rotated and scanned around the optical axis of the imaging lens, the resolution %l
is determined by J=r−tanψ (where r is the radius of the circular object visual field and ψ is the rotation angle), and does not include the imaging distance.

〔Example〕

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

FIG. 1 is a configuration diagram showing an imaging device according to an embodiment of the present invention. In the figure, (4) indicates an imaging lens (2) and -
The detection head 00 integrated with the dimensional optical sensor (3b) is
Imaging lens (arrow (b) centered on the optical axis (to) of 21)
(9) is a conversion circuit that converts a polar coordinate signal obtained by rotational scanning into a rectangular coordinate signal.

Next, the operation of the imaging device according to an embodiment of the present invention will be described.

The detection head α0 that integrates the one-dimensional optical sensor (3b) and the imaging lens (2) is shown in the scanning diagram 1i! (5) and the moving mechanism (
4), each time the -dimensional optical sensor (3b) completes electrical scanning, it is rotated by ψ degrees N times, and the above operation is repeated until ψ・N=180 (degrees)...(2). I'll give it back. Thereby, a circular two-dimensional field of view (1) can be imaged on the object plane.

At this time, the resolution l in the ψ direction determined by the moving mechanism (4) is worst at the peripheral edge of the circular field of view, and 1 = r
-tan (p -(31).

Here, r is the radius of the circular object visual field (1), and ψ is the rotation angle. As can be seen from the above, the above resolution requires the imaging distance M.
L is not included. In other words, the moving mechanism (4) can be driven without considering the influence of the imaging distance.

The output of the optical sensor (3b) obtained by the above-described rotational scanning is input to and processed by the processing section (8) similar to that of the conventional device. However, in this case, the output is a polar coordinate signal obtained every ψ degree, so in some cases, this may be converted to
A conversion circuit (9) for converting into a Y orthogonal coordinate signal is used.

Also, in the above explanation, the optical axis of the imaging lens (2) and the center of the light receiving surface of the optical sensor (3b) are aligned, but
This can also be configured by changing the relationship between the two, as shown in FIGS. 2(a) and 2(b). In the case shown in Fig. 2, by performing rotational scanning until ψ・N=360 (degrees) (4), a circular shape as shown in Fig. 2(a), or a circular shape as shown in Fig. 2(a) is obtained. A donut-shaped two-dimensional field of view (1) as shown in b) is obtained.

Note that in the above embodiment, the imaging lens (2) and the optical sensor (3)
b) are integrated so that they can be rotated at the same time, but the same effect can be obtained even if only the optical sensor (3b) is rotated. Further, although no specific example was given regarding the moving mechanism (4) in the above embodiment, this can be easily realized using conventional technology, and the rotation direction may be always fixed or reversed each time the field of view is imaged. You can do it like this.

〔Effect of the invention〕

As described above, according to the present invention, since the one-dimensional optical sensor is rotated around the optical axis of the imaging lens to obtain a two-dimensional field of view, images can be captured without being affected by the imaging distance to the imaging target. This has the effect of enabling long-distance imaging with high resolution. Furthermore, the device is capable of high-speed imaging and has the advantage of being inexpensive.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an imaging device according to an embodiment of the present invention, FIG. 2(a) (υ is a configuration diagram showing an imaging system of an imaging device according to another embodiment of the invention, and FIG. a) (b)
) (c) is a block diagram showing the imaging system of the conventional imaging device, FIG. 4 is a block diagram showing the signal processing system of the conventional imaging device, and FIG. 5 is an explanation explaining the resolution of the conventional imaging device. It is a diagram. (1)... Two-dimensional field of view, (2)... Imaging lens, (
3b)...-dimensional optical sensor, (4)... moving mechanism,
(5)...Scanning circuit, (8)...Processing section, (9)...
... Conversion circuit, wire... Optical axis In the drawings, the same reference numerals indicate the same or equivalent parts.

Claims (4)

[Claims] (1) An imaging lens that images an object, a one-dimensional optical sensor in which a plurality of light receiving elements are arranged linearly on the imaging plane of the imaging lens, and the optical sensor is rotated around the optical axis of the imaging lens. an imaging device comprising: a moving mechanism for moving the object; a scanning circuit for driving the optical sensor and the moving mechanism; and a processing unit that processes the output of the optical sensor and the signal of the scanning circuit to create a signal for recognizing the object. (2) The imaging device according to claim 1, in which the optical axis of the imaging lens and the center of the optical sensor are made to coincide with each other, and a circular two-dimensional field of view is obtained by rotationally moving through 180 degrees. (3), by shifting the optical axis of the imaging lens and the center of the optical sensor,
The imaging device according to claim 1, which obtains either a circular or donut-shaped two-dimensional field of view through 360° rotational movement. (4) The imaging device according to any one of claims 1 to 3, wherein the processing section includes a conversion circuit that converts a polar coordinate signal obtained from the scanning circuit into a rectangular coordinate signal.