JPS6152603A - Image fiber optical system - Google Patents

Abstract

PURPOSE:To utilize effectively the resolution of a TV camera and an image fiber by recombining a strand for constituting the image fiber so that a shape of the end face of an image pickup object side is different from a shape of the end of an image pickup means side, and filling the almost whole area of an image pickup surface with an object image. CONSTITUTION:As for end faces E1, E2 of an image fiber 50, partial fibers 50a, 50b are placed in the horizontal direction to match a slender object 1 as shown in (A), at an objective lens 4 side, and in the vertical direction to match a shape of an image pickup surface 3 as shown in (B), at an image pickup lens 6 side. Accordingly, an image of a left half 1a of the object 1, and an image of a right half 1b are inputted to the side of the partial fiber 50a and the side of the partial fiber 50b, respectively. The image transmitted by the image fiber 50 is outputted from the end face E2 of its opposite side, and through the image pickup lens 6, the left half 1a and the right half 1b are made to form an image on the upper side of the image pickup surface 3 and the lower side, respectively. Therefore, the greater part of the image pickup surface 3 is occupied by an image of the object 1, a ratio of the number of significant picture elements increases.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] This invention relates to an image fiber optical system used in an image input device such as an automatic visual inspection device.

[Prior art and its problems]

In the following explanation of each figure, the same reference numerals indicate the same or corresponding parts.

An image input device such as a general +C TV camera is used in an automatic visual inspection device. However, the resolution of the TV camera is limited, and if the inspection object (also called object or imaged object) 1 has an elongated shape, as shown in the example shown in Fig. This results in a screen consisting of a wide meaningless area 3b that cannot be viewed on one screen, and almost the entire area of the imaging surface 3 is covered with the object image 3.
There is a drawback in that it is not possible to increase the amount of image information obtained from the object image 3a through the imaging surface 3 by enlarging the image a, in other words, it is not possible to effectively utilize the resolution of the TV camera 2.

Fig. 7 shows an example using an image fiber optical system descended from the image input section, where 5 is an image fiber made of an optical fiber cable, 4 is an objective lens, 6 is an imaging lens, 3 is a TV camera, and a solid-state image sensor. This is the imaging surface of an imaging means such as. An optical system using such an image fiber 5 is used for inspecting the inside of a narrow place, but in this case as well, if the object 1 to be inspected has an elongated shape as described above, the entire object can be viewed in one screen. If you try to observe the image using the image fiber, you cannot make effective use of the resolution of the image fiber. In addition, an enlarged view of a partial image 9 of the object image 3a within the imaging surface 3 in FIG. Object image 3 with the entire area of surface 3 enlarged
Since a is smaller than when it is filled in, the first part image 9
The amount of information acquired from the image is also small, so there is a drawback that sufficient (and therefore accurate) image information of the object image 3 cannot be transmitted.

[Purpose of the invention] surface This invention can be used to directly display a long and narrow object on a TV screen.

Or, as in the case of imaging with a general image fiber (except for the disadvantage that there are many meaningless areas on the screen), almost the entire imaging surface is filled with the object image.
It is an object of the present invention to provide an image fiber optical system that can effectively utilize the resolution of a camera and an image fiber.

[Key points of the invention]

The gist of the present invention is to input an image of an object to be imaged through an image fiber, and then provide an optical system for capturing the image through an imaging means (TV camera, solid-state image sensor, etc.), the object being imaged by the image fiber. The shape of the end face on the object side is
A point in which the fiber wires constituting the image fiber are recombined so as to have a different shape from the end face of the image fiber on the imaging means side, or further,
The shape of the end face of the image fiber on the side of the object to be imaged is similar to the outline shape of the image of the object to be imaged inputted into the image fiber ζ or the shape formed by the envelope of the outline, and the shape of the end face of the image fiber on the side of the imaging means is similar The shape of the imaging surface of the imaging means is similar to that of the imaging means.

[Embodiments of the invention]

The present invention will be described in detail below with reference to FIGS. 1 to 4. FIG. 1 is a diagram showing the configuration of an image fiber optical system as an embodiment of the present invention, FIG. 2 is a diagram showing the structure of the end face of the image fiber in FIG. Figure ■ shows the imaging lens side. FIG. 3 is a diagram showing an example of the object image on the imaging surface in FIG. Figure ■ shows the imaging lens side.

In FIG. 11ζ, 50 is a new image fiber, in this example two partial fibers 50a.

50b. Further, El and E2 are the end faces of the n-image fiber SO+C on the objective lens 4 side and the imaging lens 6 side, respectively. On the objective lens 4 side, the end surfaces E1 and E2 form a partial fiber 50a, which is a long and narrow object as shown in FIG.

50b is arranged in the 1M direction, and on the side of the imaging lens 6, as shown in FIG. Therefore, the image of the left half 1a of the object 1 is projected onto the side end of the partial fiber 50a by the objective lens 4, and the image of the right half 1b is projected onto the side of the partial fiber 50b. be done. The image input in this way is transmitted to the image fiber 5.
0(50a, 50b) The lower half 1b is imaged.

The object image 3a on the imaging surface 3 is formed with an external shape close to that of the imaging surface 3, as shown in FIG. 3F.

For this reason, the end face of the image fiber 50, and therefore most of the imaging surface 3, is occupied by the image of the object 1, and the image involved in transmitting image information of the object 1 or extracting an image signal. The number of fiber strands in the fiber 50 or the proportion of significant pixels in or extracted from the imaging surface 3 also increases.

That is, in the present invention, it is possible to reduce meaningless parts (not related to image information) on the screen of a TV camera, and enlarge and image significant parts (related to image information) over the entire screen. , the resolution of the TV camera can be effectively utilized.

Next, in FIG. 4, the image fiber 50 is composed of three partial fibers 50d, 50e, and 50f, and the end surface E1 on the objective lens 4 side corresponds to the inverted T-shaped outline of the object 1 (not shown). With a T-shaped shape, the image of object 1 is
On the other hand, the partial fibers 50 e - f are combined so that the end face E2 on the side of the imaging lens 6 has a vertical injection ratio equal to the FI'tr ratio of the imaging surface 3.
An image of the object 1 is formed over the entire area tζ.

Therefore, in this embodiment, the resolution of the TV camera and image fiber can be effectively utilized.

〔Effect of the invention〕

As is clear from the above explanation, according to the present invention, the end face on the objective lens side of the image fiber optical system is made similar to the contour shape t of the significant region of the input image of the object, and the end face on the imaging lens side 7il - imaging The shape of the imaging surface of the means is similar to this shape, and it is designed so that the significant contour area of the object is contained in the entire imaging surface, so that the image of the object can be captured within the size of the imaging surface. It is now possible to enlarge and capture a large amount of data, and the resolution of the image fiber and TV camera can be used effectively to the maximum.

For this reason, high resolution can be obtained, making it possible to perform high-definition inspections in automatic visual inspections, etc.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of an image fiber optical system as an embodiment of the present invention, FIG. 2 is a diagram showing the structure of the end face of the image fiber in FIG. 1, and FIG. FIG. 4 is a diagram showing an example of an image of an object on an imaging surface, FIG. 4 is a diagram showing an end face structure of an image fiber in another embodiment of the present invention, and FIG. 5 is a diagram showing an example of an image of an object on an imaging surface. 6 is a diagram showing the object image on the imaging surface in FIG. FIG. 8 is a diagram illustrating a part of the transmitted image in the image fiber corresponding to the object image on the imaging plane in FIG. 7 (illustration). 1...Object, 1a...Left half of the object, Ib...Right half of the object, 3...Photograph is a plane, 4...Curved objective Lens, 6... Imaging lens,
50... Image fiber, 50a, 50b.
...Partial fiber, El, E2...End face, 3a...Object image. -1; Figure 3 Figure 4 Figure O 6 ■

Claims (1)

[Claims] 1) In an optical system that inputs an image of an imaged object via an image fiber and captures the image via an imaging means, the shape of the end face of the image fiber on the side of the imaged object is:
An image fiber optical system characterized in that fiber wires constituting the image fiber are recombined so that the shape of the end face of the image fiber on the imaging means side is different. 2) In the optical system according to claim 1, the shape of the end face of the image fiber on the side of the object to be imaged is the contour shape of the image of the object to be imaged that is input to the image fiber or the envelope of the contour. An image fiber optical system characterized in that the shape of the end face on the imaging means side is similar to the shape of the imaging surface of the imaging means.