JPH11153516A - Imaging device - Google Patents

Abstract

(57) Abstract: An object of the present invention is to provide an apparatus capable of imaging a wide area with high resolution in a short time when imaging an inspection object having a fine pattern over a wide area. A measurement light irradiating means for irradiating a measurement light to a test object, and a light guide group for transmitting light from the test object.
A group of image forming means 20 for forming an image on an end surface on the side of the object to be inspected, a group of light guides for guiding light from the group of image forming means 20 to be inspected to a group of image forming means 50, An imaging side imaging means group 50 for imaging light from the light guide group on the imaging element group 60; and an imaging element group 6 for imaging an image of the inspection object.
0 and a circuit for outputting this image as data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup apparatus for picking up an image of a wide area at a high resolution, and includes a fine component such as a color filter or a shadow mask which is a component constituting an image surface of various display devices. It can be used for image capturing and the like for inspection of an object having a pattern formed over a wide range.

[0002]

2. Description of the Related Art Components constituting an image surface of a display device, such as a color filter of a liquid crystal display device and a shadow mask of a CRT monitor, have a pattern of several tens to several hundreds of microns in an area of several tens to several hundred cm. Is formed, and has a feature that a fine pattern is formed over a wide range.

Conventional inspection methods for parts having the above characteristics are either a method of inspecting by imaging the entire region at low resolution, or a method of imaging and inspecting a partial region at high resolution. Was.

[0004]

However, in the method of imaging and inspecting the entire area at a low resolution, it is generally difficult to detect a minute defect because the resolution is low. Further, moire may occur between the cycle of the pixels of the image sensor and the cycle of the pattern formed on the inspection object, and there is a disadvantage that the quality of the captured image is significantly reduced due to the moire.

[0005] In the case of a method of inspecting by imaging at a high resolution, a conventional imaging apparatus using a magnifying optical system such as a microscope and an imaging system such as a CCD camera can image only a partial area at a time. In general, in an imaging device using an enlargement optical system, the size of the optical system and the imaging system is larger than the size of the imaging region. In a conventional apparatus using a magnifying optical system and an imaging system, it is not possible to make the imaging regions continuous by simply simply arranging them in parallel. Accordingly, there is a problem that it takes too much time to image a wide area with high resolution, and the apparatus itself is complicated, which is not practical.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem when an object to be inspected having a fine pattern is imaged over a wide area, and an apparatus which can image a wide area in a short time is provided. The purpose is to provide.

[0007]

According to the present invention, there is provided an imaging apparatus for imaging a wide area with high resolution,
A measurement light irradiating unit for irradiating the inspection object with the measurement light, an inspection object side imaging unit group for forming an image of light from the inspection object on an end surface of the light guide group on the inspection object side, and an inspection object A light guide group that guides light from the side imaging unit group to the imaging side imaging unit group, an imaging side imaging unit group that forms light from the light guide group on the imaging element group, and an image of the inspection object. And a circuit that outputs this image as data.

According to a second aspect of the present invention, there is provided an imaging apparatus for imaging a wide area at a high resolution, comprising: a measuring light irradiating means for irradiating the inspection object with measurement light; A beam splitter group that divides the light into a plurality of optical paths to the imaging side imaging unit group, an imaging side imaging unit group that forms light from the beam splitter group on the imaging element group, and an image of the inspection object. An image pickup apparatus includes an image pickup element group for picking up an image and a circuit for outputting the image as data.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. According to the image pickup device of claim 1,
Light from the inspection object (10) at the imaging position is passed onto the imaging element group (60) through the inspection object side imaging means group (20), the light guide group (40), and the imaging side imaging means group (50). Be guided. At this time, a predetermined number of imaging side imaging means and imaging elements are arranged, and light from a certain predetermined imaging range is guided onto the imaging element by a light guide, so that an image of each part of a continuous region is specified. Can be imaged at a magnification of.

[0010] According to the image pickup apparatus of the second aspect,
The optical path of the light from the inspection object (10) at the imaging position is divided into a plurality of light paths by the beam splitter groups (70a, 70b), and the imaging device group (6) is passed through the imaging side imaging means group (50).
0) is directed above. Each imaging element captures an image in a different imaging range, so that an image of each part of a continuous area can be captured at a predetermined magnification.

[0011]

FIG. 1 is a diagram showing a schematic configuration of an image pickup apparatus according to an embodiment of the present invention. In this figure, the inspection object (10) is transported to an imaging position by a transport device (not shown), and each part of the inspection object (10) sequentially passes through the imaging position to image the entire inspection object.

[0012] (1a) and (1b) are measurement light irradiation means installed near the imaging position. One or both of the transmission-type measurement light irradiating means (1a) and the reflection-type measurement light irradiating means (1b) are turned on in accordance with the characteristics and the inspection method of the inspection object (10), and the inspection position at the imaging position is inspected. The object (10) is irradiated with measurement light.

When both the transmission-type measuring light irradiating means (1a) and the reflection-type measuring light irradiating means (1b) are used at the same time, the wavelength range and the polarization state of the light to be irradiated are made different from each other. By doing so, when a defect of the inspection object (10) is recognized on the captured image, it is possible to distinguish which of the transmitted light and the reflected light contributes.

By the inspection object side imaging means group (20),
Light from the inspection object (10) is applied to the inspection object side imaging surface group (3
0) and is guided to the light guide group (40).

The inspection object side imaging means group (20) includes:
Various lenses such as a photographing lens can be used. The inspection object side imaging means (21, 22,...)
0), the respective imaging ranges (11a, 11b, 11)
c, 11d, 12a, 12b, 12c, 12d ...)
Are grouped by a predetermined number, and the inspection object side imaging surface group (3
0).

The light guide group (40) includes light guides (41a, 41b, 41c, 41d, 42a, 42b,
42c, 42d...), The object-side imaging surface is located at the end face of the light guide, and both (the object-side imaging surface and the light guide) are directly connected to each other and The light from the object (10) is guided to the imaging-side imaging means group (50). That is, one image sensor is assigned corresponding to each imaging range.

As the light guide, a light guide whose end face is polished by bundling optical fibers as shown in FIG. 3 can be used.

The imaging-side imaging means group (50) includes the imaging-side imaging means (51a, 51b, 51c, 51d, 52a, 52).
, 52c, 52d,...) are arranged, and the light from the light guide is transmitted to the image pickup devices (61a, 61a,
61b, 61c, 61d, 62a, 62b, 62c, 6
2d...) Is formed at a predetermined magnification.

Various lenses such as a photographing lens can be used as the image forming side image forming means. Light guides (41a, 41b, 41c, 41d, 42a, 42b,
42c, 42d,...) Can have the function of the imaging side image forming means. In other words, when the light guide is a bundle of optical fibers as shown in FIG. 4, the thickness of each optical fiber is increased from the object to be inspected toward the imaging means, and the image of each light guide is What is necessary is just to install each imaging element in close contact with the means side end surface.

The image pickup means group (60) includes an image pickup element (61a,
61b, 61c, 61d, 62a, 62b, 65c, 6
5d...) Are arranged, and an image formed on the image sensor is captured and output as image data. As the imaging device, various light receiving elements such as a CCD line sensor and various cameras can be used.

Next, the operation performed by the image pickup apparatus of the above embodiment will be described with reference to FIG. A predetermined imaging range (11a, 11a) of the inspection object (10) at the imaging position.
b, 11c, 11d, 12a, 12b, 12c, 12d
..) From the object-side imaging means (21, 2).
2), the light guides (41a, 41b, 41c, 4)
1d, 42a, 42b, 42c, 42d,...) Are formed on the inspection object side imaging surface (30) located at the end surface.

The image of one imaging range (11a) is guided to the imaging side imaging means (51a) by the corresponding light guide (41a), and is enlarged to a predetermined magnification by the imaging side imaging means. An image is formed on the image sensor (61a) on the image pickup means and output as partial image data. Also, light from the imaging range (11b) adjacent to the imaging range (11a) forms an image on the imaging element (61b) on the imaging means through the same process and is output as partial image data. By performing the above process for the entire imaging range of the imaging position, a partial image data group of the entire imaging range is obtained, and the inspection object (10)
Can be obtained.

The partial image data group output from the imaging means group (60) in this way is sent to an image processing means (not shown), where it is combined as one image, but the imaging means group is continuous as a whole. Since the regions are imaged at the same timing, there is an advantage that the image combining procedure is simple. Further, the width of the imaging-side imaging means group and the imaging means group can be set to be equal to or less than the width of the inspection object by arranging them in a direction orthogonal to the arrangement of the imaging range. A compact device is possible.

In order to increase the resolution, the image pickup range (11a, 11b, 11c, 11d,
12a, 12b, 12c, 12d...)
What is necessary is just to increase the magnification of the imaging side imaging means group (50) and increase the number of imaging element groups (60) and the like.

In the second embodiment of the present invention, as shown in FIG. 4, an optical fiber that is thin on the object to be inspected and thick on the imaging means group is used as the light guide group (40). It is used by bundling and polishing both end faces. By making each optical fiber thicker by a predetermined ratio on the imaging means side than on the inspection object side, it is possible to perform imaging at a predetermined magnification without the imaging side imaging means group (50). When such an optical fiber having a thinner diameter of 2 μm and a thicker diameter of 8 μm is used, the light guide group is enlarged four times. Image sensor (61a, 61
b, 61c, 61d, 62a, 62b, 65c, 65d
..) Are light guides (41a, 41b, 41c,
41d, 42a, 42b, 42c, 42d...).

The light guide group (40) of the second embodiment.
Alternatively, a light guide in which optical fibers are bundled may be hardened by compression melting or various kinds of adhesives, formed into a shape as shown in FIGS. 3 and 4, and both ends thereof may be polished. Such a light guide has an advantage that it can be easily installed and has high strength.

FIG. 5 is a schematic diagram illustrating an image pickup apparatus using a beam splitter according to a second embodiment of the present invention. In this figure, for simplicity, only the transmission type measuring light irradiating means (1a) is illustrated as the measuring light irradiating means.
A reflection type measuring light irradiation means may be used, or both may be used simultaneously as described above.

The beam splitters (70a, 70b) divide the optical path of light from the image pickup position, and may use a half mirror, a pellicle beam splitter, a cube beam splitter, or the like. The light split by the beam splitter is respectively transmitted to the imaging-side imaging means group (5
1a, 51b, 51c,...) To form an image at a predetermined magnification, and a group of imaging means (61a, 61b, 61c,...).
..).

As described above, by dividing the light by the beam splitter, the size of the image pickup device constituting the image pickup means group can be increased. That is, it is possible to increase the magnification of an image obtained by increasing the size of the image sensor.

Hereinafter, the operation performed by the above-described image pickup apparatus according to claim 2 will be described. The inspection object (1) at the imaging position
The light of the predetermined imaging range (11a) of (0) is guided to the imaging-side imaging means (51a) after the optical path is divided by the beam splitter (70a). Imaging side imaging means (51
a) is a predetermined imaging range (11a) of the inspection object (10).
Is arranged so as to form an image on the imaging element (61a) on the imaging means by enlarging only the light from the imaging device to a predetermined magnification. Further, an imaging range (11b) adjacent to the imaging range (11a)
The light from the imaging device (6)
1b) Image on top. By performing the above process for the entire imaging range at the imaging position, partial image data of the entire imaging range can be obtained.

In this way, the image pickup devices (61a, 61a)
b,...) are sent to an image processing unit (not shown), where they are combined as a single image. Since the imaged area is imaged at the same timing, there is an advantage that the procedure for combining the images can be simplified. Further, since the width of the imaging side imaging means group, the imaging means group, and the like can be set to be equal to or less than the width of the inspection object, the device can be spatially compact in the width direction.

In FIG. 5, the light from the imaging range is transmitted to a beam splitter (70b) at a transmission: reflection ratio of 2: 2.
When it is set to 1, the light amount of the image pickup element (61b) that receives the reflection component is １ ／ of the original light amount. The light transmitted through the beam splitter (70b) becomes 1/3 each of the original light when the transmission: reflection ratio is 1: 1 and the brightness of the combined image is reduced. Will be aligned.

Also in the case of the second aspect of the invention, in order to increase the resolution, the imaging range per one imaging element is reduced, the number of beam splitters for dividing the optical path, the number of imaging side imaging means, the imaging means. May be increased to increase the magnification of the imaging side image forming means and the like.

[0034]

According to the image pickup apparatus of the present invention, the image pickup means and the image pickup means are arranged by a predetermined number, and the light from each part of the image pickup position is guided onto each image pickup means to provide a predetermined magnification. Therefore, it is possible to image a wide area with high resolution in a short time.

Further, since a continuous area is imaged at the same timing by the entire image pickup means, there is an advantage that the procedure for combining images is simple.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an example of an image capturing apparatus according to claim 1 of the present invention.

FIG. 2 is a conceptual diagram illustrating an example of the image pickup apparatus according to claim 1 of the present invention.

FIG. 3 is a conceptual diagram illustrating a light guide group used in the image pickup apparatus according to claim 1 of the present invention.

FIG. 4 is a conceptual diagram illustrating a light guide group for obtaining a high magnification used in the image pickup apparatus according to claim 1 of the present invention.

FIG. 5 is a schematic diagram illustrating a configuration of an image pickup apparatus using a beam splitter according to claim 2 of the present invention.

FIG. 6 is a conceptual diagram illustrating an image pickup apparatus using a beam splitter according to claim 2 of the present invention.

[Explanation of symbols]

1a: Transmission type measuring light irradiating means 1b: Reflection type measuring light irradiating means 10: Object to be inspected 11a to 11d, 12a to 12d: Image pickup range per one of each image sensor 20: Object to be inspected Image unit groups 21 and 22... Inspection object side imaging means corresponding to imaging range 30. Inspection object side imaging surface group 40. Light guide groups 41 a, 41 b to 42 c and 42 d. 50: imaging side imaging means group 51a, 51b to 52c, 52d: imaging side imaging means corresponding to each imaging range 60: imaging element group 61a, 61b to 62c, 62d: imaging element corresponding to each imaging range 70a, 70b ... Beam splitter

Continued on the front page (51) Int.Cl. ⁶ Identification code FI H04N 5/335 H04N 5/335 V 7/18 7/18 B

Claims (2)

[Claims] An imaging apparatus for imaging a wide area with high resolution, comprising: a measuring light irradiating means for irradiating a measuring light to the inspection object; and light from the inspection object on a side of the inspection object side of a light guide group. An object-side imaging means group for forming an image on the end surface, a light guide group for guiding light from the object-side imaging means group to the imaging-side imaging means group, and an image sensor for emitting light from the light guide group An image pickup apparatus comprising: an image pickup side image pickup means group for forming an image on a group; an image pickup element group for picking up an image of an object to be inspected; and a circuit for outputting the image as data. 2. An imaging apparatus for imaging a wide area at a high resolution, comprising: a measuring light irradiating means for irradiating a measuring light to an object to be inspected; A beam splitter group that leads to the imaging unit group, an imaging-side imaging unit group that forms light from the beam splitter group on the imaging device group, and an imaging device group that captures an image of the inspection object,
And a circuit for outputting the image as data.