JPH0855889A - Image connection device - Google Patents

Abstract

PURPOSE:To form the image of a plurality of separated parts to be inspected at one image pick-up element without any distortion by providing a plurality of masks for separating an unneeded part on a primary image-forming surface by an image-forming lens and then leading the image of the part to be inspected through the plurality of masks onto one image pick-up element which is a secondary image-forming surface for forming an image. CONSTITUTION:The images of parts A and B to be inspected are formed on a primary image-forming surface 2 by an image-forming lens 3 and masks 4 and 5 are laid out on the primary image-forming surface 2 for separating an unneeded part. For forming an image through the masks 4 and 5 on an image pick-up element 7 where the image of the parts A and B to be inspected on the primary image-forming surface 2 are laid out on a secondary image- forming surface 6 on a light axis of the first imageforming lens 3 by second and third image-forming lenses 8 and 9, mirrors 10 and 11 are deflected and the deflected image is connected by a combination prism 12 and is led to the image pick-up element 7, thus forming the images of the separated parts A and B to be inspected on one image pick-up element 7 without any distortion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention, when inspecting a plurality of lead portions of an IC, for example, forms an image forming image which enables simultaneous measurement of a plurality of lead portions (places to be inspected apart on the face to be inspected). More specifically, the present invention relates to an image forming apparatus that separates unnecessary portions and can monitor only a necessary test portion.

[0002]

2. Description of the Related Art Conventionally, when a plurality of locations (inspection locations) that are on the object plane but are distant from each other are imaged on an image pickup device using a television camera lens optical system, for example, there are two inspection locations. If so, it is necessary to use two TV camera lens optics.

For example, when an attempt is made to inspect (measure) a plurality of lead portions of an IC, each lead portion is photographed by a plurality of television camera lens optical systems, that is, each lead portion is imaged on a plurality of image pickup elements, and these are formed. The image is divided and displayed on one monitor screen.

As described above, by using a plurality of television camera lens optical systems, it is possible to monitor a plurality of locations to be inspected, and it is possible to easily inspect (measure) the lead portion of the IC.

[0005]

However, use of a plurality of the television camera lens optical systems inevitably increases the cost. Further, there are disadvantages that the image processing for combining a plurality of images becomes complicated and the image processing speed takes time.

Further, for example, in the inspection (measurement) of a plurality of lead portions of an IC, it is necessary to magnify and photograph only the lead portions, that is, the portions other than the lead portions are not required. Therefore, if it is possible to form an image of a plurality of lead portions (a plurality of locations to be inspected at a distance) on one image sensor, it is possible to measure a necessary portion with high magnification and in a short time with high magnification. Not only is it possible to reduce costs. However, as described above, when an image of a plurality of lead portions taken by a plurality of TV camera lens optical systems is formed on one image pickup device, the optical axes of the TV camera lens optical systems are tilted. The image on the image sensor is distorted, and the images of a plurality of test locations on the image sensor are overlapped at the boundary, so that there is a disadvantage that an unusable portion is generated.

The present invention has been made in view of the above problems, and an object thereof is to form images of a plurality of distant test locations on a single image pickup device without distortion and separate unnecessary portions. An object of the present invention is to provide an image forming apparatus capable of obtaining an image of only a plurality of inspection points.

[0008]

In order to achieve the above object, the present invention is an image forming apparatus capable of forming an image of a plurality of test points separated on the test surface on an image pickup surface. One image-forming lens or a plurality of image-forming lenses capable of forming an image on the plurality of inspection points, a plurality of masks for separating unnecessary portions on a primary image-forming surface formed by the image-forming lenses, and a plurality of masks are provided. The gist of the present invention is to include an optical system that guides an image of a passing inspection site onto one image pickup element which is a secondary image formation surface to form an image. Further, the optical system respectively forms a plurality of image forming lenses capable of forming an image of the primary image forming surface on the image pickup element, and images from the same image forming lens on an optical axis of the plurality of image forming lenses. It is composed of a plurality of deflecting mirrors and a combination half prism that combines the images through the plurality of mirrors and guides them onto the image pickup device.

[0009]

According to the above means, the images of the plurality of inspection points on the surface to be inspected are formed on the primary image forming surface by one image forming lens or a plurality of image forming lenses. Since the mask is arranged on this primary image forming surface, the image of the inspection site where the unnecessary portion is separated is incident on the optical system which guides it to the image sensor through the mask. In the optical system, in order to form each image on the primary image forming surface on the image pickup element by the image forming lens, the image from the image forming lens is deflected by each mirror, and the deflected image is formed by the combination prism. They are combined and guided to the image sensor. Since this image pickup element is arranged on the image forming surface (secondary image forming surface) of each image forming lens, a plurality of test points are imaged on the image pickup element. In this way, since a plurality of inspection points are imaged on one image sensor and unnecessary portions are separated by each mask, only a plurality of necessary inspection points are formed on one image sensor. It is imaged.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image forming apparatus according to the present invention is provided with a primary image forming surface formed by forming an image of a plurality of distant inspection points on an object surface (inspection surface), which is masked to separate unnecessary portions. Focusing on the fact that an image of only a plurality of distant test points can be formed on one image sensor without distortion by introducing an image of a large test point onto the image sensor on the secondary imaging plane, Images of a plurality of test locations on the image plane are combined using an imaging lens, a mirror, and a combination half mirror to be combined into one image pickup element arranged on a secondary imaging plane which is an imaging plane of the imaging lens. Image.

Therefore, the image forming apparatus of the present invention is shown in FIG.
It has the configuration shown in. In FIG. 1, the image forming apparatus includes a first image forming lens 3 for forming two image points A and B apart from each other on a surface 1 to be inspected on a primary image forming surface 2, and a primary image forming surface 2.
The masks 4 and 5 for separating unnecessary portions and the images of the inspection points A and B on the primary image forming surface 2 can be formed on the image pickup device (CCD or the like) 7 arranged on the secondary image forming surface 6. Second and third image forming lenses 8 and 9, and mirrors 10 and 11 for deflecting each image in order to guide the image of the inspection points A and B on the secondary image forming surface 6 to the image sensor 7. And a combined half prism 12 for combining the deflected images. The second and third imaging lenses 8 and 9, the mirrors 10 and 11, and the combination half prism 12 correspond to the optical system according to claim 1. Further, the mask 4, the second imaging lens 8 and the mirror 10 and the mask 5, the third imaging lens 9 and the mirror 11 are preferably symmetrical with respect to the optical axis of the first imaging lens 3. .

The mirror 10 is on the optical axis of the second imaging lens 8, the mirror 11 is on the optical axis of the third imaging lens 9, and the image pickup element 7 and the combination half prism 12 are the first.
On the optical axis of the imaging lens 3. Therefore, the second and third image forming lenses 8 and 9 form images of the primary image forming surface 2 on the secondary image forming surface 2 located at the distance of the optical path through the mirrors 10 and 11 and the combination half prism 12, respectively. Is designed to be.

As shown in FIG. 2, the combination half prism 12 has four prisms 12 when there are two test points.
The prism 12a has a half mirror coating on one side. As is clear from FIG. 2, the coating of each prism 12a is applied so that half of the light from the left and right directions is reflected downward in the figure. Specifically, the light from the a1 direction on the left side of FIG. 2 is reflected in the a11 direction, and the light from the a2 direction is reflected in the a21 direction. Light from the b1 direction on the right side of FIG. 2 is reflected in the b11 direction, and light from the b2 direction is reflected in the b21 direction. Therefore, the light is combined with the prism 12
Depending on which part of the light enters, the reflection is left-right reversed with the dashed-dotted line (center) in FIG. 2 as the boundary.

According to the image forming apparatus having the above-described structure, the primary image forming surface 2 is provided with the first image forming lens 3 to be inspected locations A and B.
Image is formed. Since the masks 4 and 5 are arranged on the primary image formation surface 2, distant test points A on the test surface 1
Only the image of B passes through the masks 4 and 5. Therefore, depending on the size of the masks 4 and 5, it is possible to separate the unnecessary portions and obtain only the required inspection points A and B.

The images of the required inspection points A and B obtained by the masks 4 and 5 are formed on the secondary image forming surface 6 by the second and third image forming lenses 8 and 9. At this time, in order to form the images of the inspection points A and B on the image sensor 7 having different optical axes, the images of the inspection points A and B are deflected by the mirrors 10 and 11 to form the first image. The light enters the combined half prism 12 on the optical axis of the lens 3. The combination half prism 12 is
As shown in FIG. 2, the light from the mirror 10 is reflected in the direction of the image sensor 7, while the light from the mirror 11 is similarly reflected in the direction of the image sensor 7. In other words, the combination half prism 12 combines the images from the left and right directions and guides them to the image pickup device 7.

Therefore, even if the inspection points A and B are separated from each other, the optical axes are not inclined, and the inspection points A and B can be imaged on one image pickup device 7, and the masks 4 and 5 can be formed. The unnecessary portion can be removed by. Further, by adjusting the positional relationship between the mirrors 10 and 11 and the combination half mirror 12, it is possible to adjust the distance between the images of the test locations A and B on the image sensor 7, and it is impossible to use. The parts can be adjusted. In this case, by moving the combination half prism 12 and the image pickup device 7 in the vertical direction at the same time in FIG. 1, it is possible to move the images of the inspection points A and B on the image pickup device 7 at the same time. You can also stack and reverse the position. As a result, when the distant inspection points A and B are different from each other, or when it is desired to change the image forming interval between the inspection points A and B, it is possible to move some optical elements without significantly changing the optical system. , The inspection locations A and B can be imaged on the image sensor 7 at appropriate intervals. In the above-described embodiment, the case where the images of the two test locations A and B are formed on the image sensor 7 has been described, but the same concept can be applied even if the number of test locations is large. In this case, the number of imaging lenses and mirrors may be increased according to the number of locations to be inspected, and the configuration of the combination half prism 12 may be changed.

When the above image combining device is used to inspect the lead portion of an IC, for example, an image of only a plurality of lead portions that are distant from each other is formed on the image pickup element 7, there is no distortion, and the boundary is clearly separated. be able to. Therefore, the required lead portion can be enlarged and photographed, and highly accurate measurement can be performed. In addition, a CCD used as the image sensor 7
Since the integration degree of pixels such as etc. is improved and one CCD etc. is divided into plural and image processing technology is developed,
By collecting the information of multiple images in one image sensor,
It is also possible to process information efficiently.

As described above, by simply combining the imaging lens, the mirror and the combination prism, it is possible to obtain the same operation as, for example, a plurality of television camera lens optical systems, and to distort images at a plurality of distant test points without distortion. It is possible to form an image on a single image pickup device, and obtain an image of only a plurality of inspection points in which unnecessary portions are separated.

FIG. 3 is a schematic plan view of an image forming apparatus showing a modified embodiment of the present invention. In the figure, the same parts and corresponding parts as in FIG. In FIG. 3, this image forming apparatus uses fourth and fifth image forming lenses 20 and 21 in place of the first image forming lens 3 shown in FIG.

In this embodiment, the optical axis of the fourth imaging lens 20 and the optical axis of the second imaging lens 8 coincide with each other, and the optical axis of the fifth imaging lens 21 and the third imaging The optical axis of the lens 9 matches. In addition, the fourth and fifth imaging lenses 20,
The image forming surface of the image forming lens 21 corresponds to the same primary image forming surface 2.

In this case, the imaging lenses for taking the inspection points A and B are the fourth and fifth imaging lenses 20 and 21, and the two imaging lenses form the images of the inspection points A and B. An image is formed on the primary image plane 2. Therefore, it is effective when the locations A and B to be inspected are too far apart from each other and the first imaging lens 3 of the previous embodiment cannot take an image. The distance between the optical axes of the second and third imaging lenses 8 and 9 is larger than that in the previous embodiment, that is, the distance between the optical axes of the fourth and fifth imaging lenses 20 and 21 is equal to the inspection point A, Make sure you can shoot B.

As described above, since the first imaging lens 3 of the previous embodiment is replaced with the fourth and fifth imaging lenses 20 and 21, when the inspection points A and B are further apart from each other. Even in this case, it is possible to obtain the same operation and effect as those of the previous embodiment. For the action and effect, refer to the description in the previous embodiment.

[0023]

As described above, in the image forming apparatus of the present invention, a mask is applied on each of the primary image forming planes formed by forming an image of a plurality of inspection points separated on the object plane (inspection plane). Unnecessary parts are separated and the images of a plurality of test points on the primary image forming surface are combined using an image forming lens, a mirror and a combination half mirror to form a secondary image forming surface which is the image forming surface of the same image forming lens. Placed 1
Since an image is formed on one image pickup device, images of a plurality of distant test locations can be formed on one image pickup device without distortion, without using a plurality of TV camera lens optical systems, and There is an effect that it is possible to obtain an image of only a plurality of inspection points in which unnecessary portions are separated.

[Brief description of drawings]

FIG. 1 is a schematic plan view of an image forming apparatus showing an embodiment of the present invention.

FIG. 2 is a schematic partial plan view of the image forming apparatus shown in FIG.

FIG. 3 is a schematic plan view of an image forming apparatus showing a modified embodiment of the present invention.

[Explanation of symbols]

 1 Surface to be inspected (object surface) 2 Primary imaging surface 3 First imaging lens 4, 5 Mask 6 Secondary imaging surface 7 Imaging device (CCD) 8 Second imaging lens 9 Third imaging lens 10, 11 Mirror 12 Combination half prism 20 Fourth imaging lens 21 Fifth imaging lens A, B Test location

Claims (2)

[Claims] 1. An image forming apparatus capable of forming an image of a plurality of inspection points separated from each other on an inspection surface on an image pickup surface, wherein the image forming apparatus forms an image of the plurality of inspection points. A lens or a plurality of image forming lenses, a plurality of masks for separating unnecessary portions on a primary image forming surface formed by the image forming lenses, and an image of a test site passing through the plurality of masks are secondary image forming surfaces. An image combining device comprising: an optical system that guides the light onto one image pickup device to form an image. 2. The optical system comprises a plurality of image forming lenses capable of forming an image of the primary image forming surface on the image pickup device, and a plurality of image forming lenses on the optical axis of the image forming lenses. The image forming apparatus according to claim 1, comprising a plurality of mirrors that respectively deflect the images, and a combination half prism that combines the images through the plurality of mirrors and guides the images onto the image pickup device.