JPH09205568A - Image fetching device provided with lighting source - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image fetching device capable of uniformly lighting the face to be image-picked up by a lighting source without unevenness, preventing the regular reflection light from the light source from entering into the light receiving face of the image fetching means, facilitating handling and being made small in size. SOLUTION: This device 1 is constituted of an original platen 4 to set an image pickup object face 2, a light receiving face 5 to pickup the image pickup object face 2, an image pickup optical system 6 to form a real image of the image pickup object face 2 onto the light receiving face 5, a light source 7 to light up the image pickup object face 2. In this case, the image pickup optical system 6 and the light source 7 are arranged on the same side as a plane view with respect to the image pickup object face 2 while being biased toward one side and the light receiving face 5 is made parallel with the image pickup object face 2 and the optical axis of the image pickup optical system 6 is made perpendicularly to the image pickup object face 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video camera or a digital still camera which has a document table on which a photograph, a document, a three-dimensional object, etc., which constitutes a surface to be imaged is placed, and a light-receiving surface for capturing the photograph, document, etc. The present invention relates to an image capturing device with an illumination light source, which is equipped with an image capturing means such as a camera and an illumination light source including a lamp for illuminating the surface to be imaged, and is suitable for presentations and the like.

[0002]

2. Description of the Related Art As an image capturing device with an illumination light source of this type, a device as shown in FIG. 7 is conventionally known.
The image capturing device 70 with an illumination light source of the illustrated example is provided with a document table 74 on which a photograph, a document or the like forming the image capturing target surface 72 is placed, and for capturing the image capturing target surface 72 above the center of the document table 74. An image capturing device 75 such as a video camera having a light receiving surface 85 is held via an arm 80, and a pair of left and right fluorescent lamps 78 for illuminating the image pickup target surface 72 are provided on both sides of the document table 74. Illumination light source 77,
77 is held in parallel with the original table 74 via an arm 79. The illumination light source 78 and the arm 79 are rotatable in the left and right directions in a plane orthogonal to the original table 72.

In such an apparatus 70, when an image of the image pickup target surface 72 is taken, a photograph, an original document or the like forming the image pickup target surface 72 is usually positioned and placed on an original table 74, and illumination light sources 77, 77 are used. The position and orientation of the illumination light sources 77 and 77 are adjusted so that the image pickup target surface 72 is illuminated with uniform light, and then the image pickup device 75 performs the image pickup. The target surface 72 is imaged. In this case, the image of the image pickup target surface 72 is picked up by the image pickup element forming the light receiving surface 85 of the image capturing device 75 via the optical unit 76 having the objective lens 76a.

[0004]

In the conventional image capturing device 70 with an illumination light source as described above, when the image pickup target surface 72 has gloss, for example, the image pickup target surface 72 is illuminated from above. When illuminated by the light sources 77, 77, the specularly reflected light reflected by the imaging target surface 72 enters the light receiving surface 85 of the image capturing device 75. When the specularly reflected light enters the light receiving surface 85 in this way, a ghost occurs in the image and the image becomes unclear, and a desired image cannot be obtained.

In order to avoid such a problem, the illumination light source 77 and the arm 79 are usually used at the positions shown by imaginary lines. Therefore, there are problems that the device becomes large due to the arrangement of the two illumination light sources 77 and that it is inconvenient to carry.

The present invention has been made in view of the above problems, and an object thereof is to enable an illumination light source to uniformly and uniformly illuminate an image pickup target surface and to provide regular reflection from the illumination light source. An object of the present invention is to provide an image capturing device with an illumination light source, which can prevent light from entering the light receiving surface of the image capturing means, is easy to handle, and can be miniaturized.

[0007]

In order to achieve the above object, an image capturing apparatus with an illumination light source according to the present invention is provided with an original table on which an image pickup target surface is set, and an image pickup target surface. A light receiving surface, an imaging optical system for forming a real image of the imaging target surface on the light receiving surface, and an illumination light source for illuminating the imaging target surface, and the imaging optical system includes the imaging target. And the illumination light source is disposed on the same side as the imaging optical system with respect to the imaging target surface, and the light receiving surface is the imaging target. And an optical axis of the imaging optical system is perpendicular to the imaging target surface.

By doing so, it is possible to illuminate the entire image pickup surface (image pickup area) with one illumination light source and prevent specular reflection light of the illumination light emitted from the illumination light source from entering the light receiving surface. In addition, it is possible to prevent the real image of the image pickup target surface formed on the light receiving surface by the image pickup optical system from being distorted, and further, the entire image pickup target surface can be picked up by one image pickup element forming the light receiving surface.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a prerequisite embodiment of an image capturing device with an illumination light source according to the present invention.

The image capturing device 20 of the illustrated embodiment is provided with a document table 24 having a rectangular shape in plan view, on which a photograph, a document or the like constituting the image pickup surface 2 is placed, and one corner portion (corner portion) of the document table 24. The first arm 31 is rotatably supported so as to be rotatable in a plane orthogonal to the document table 24 about an axis R parallel to the document table 24 as a central axis.
A second arm 32 is rotatably supported at the tip of the second arm 32 so as to be rotatable in a plane orthogonal to the first arm 31 with the center line P of the first arm as a central axis. At the tip of the arm 32, a cover 34 having an open lower surface that covers the image capturing device 25 such as a video camera and the illumination light sources 27 and 27 '(described later) is rotated about the center line Q of the second arm 32. It is pivotally supported.

The image capturing device 25 is held in the cover 34, and the image capturing device 25 is provided with a light receiving surface 5 composed of one image pickup element, as can be seen by referring to FIG. An optical unit 26 which is built-in and has an objective lens 26a for forming a real image of the imaging surface 2 on the light receiving surface 5 is attached to the lower part of the optical unit 26, and both sides of the optical unit 26 have a predetermined inclination angle. Lamps 33, 33 'close to the light source and aspherical reflectors 34, 3 described later
Illumination light sources 27 and 27 'having 4'are attached, and the filter 2 is provided below the illumination light sources 27 and 27'.
9, 29 'are attached. Also, the lamp 3
A coating 38 that does not transmit light is applied to the lower part of 3, 33 '. The paint 38 acts as a direct light cutting means.

The reflecting umbrellas 34, 34 'have two lateral light source sections 27, as shown in FIG. 3 (A) for the lateral center section and in FIG. 3 (B) for the longitudinal center section. ，
The cross section perpendicular to the imaging surface 2 passing through 27 'is an ellipse, and the focal point Fa of one of the cross sections is made substantially coincident with the filament 35 of the lamp 33 and is orthogonal to the cross section of the cross section. A vertical cross section perpendicular to the imaging target surface 2 is a parabola, and its focus Fa is the lamp 33.
Is located outside the filament 35 of the. The longitudinal axis of the filament 35 is arranged along the parabolic cross section in consideration of the shape of the reflector 34.

Under such a structure, when the image capturing device 70 of the present embodiment is used to capture an image of the image capturing target surface 2, a photograph, a document or the like forming the image capturing target surface 2 is usually placed on a document table. The light receiving surface 5
Of the arms 31 and 32 and the image capturing device 25 so that is parallel to the imaging target surface 2 and the optical axis of the optical unit 26 overlaps with a vertical plane C passing through substantially the center of the imaging target surface 2. And the lighting source 27, 27 by appropriately adjusting the posture.
Is illuminated to illuminate the image capturing target surface 2, and the image capturing device 75 captures the image capturing target surface 72. As a result, the image of the image pickup target surface 2 is picked up by the image pickup element constituting the light receiving surface 85 of the image capturing device 75 via the optical unit 26.

Here, in this embodiment, the reflector 1
As 4, 14 ', those having an elliptical cross section and a parabolic cross section are used as described above. In general, when a spheroidal mirror is used as the reflector, the central portion usually becomes brighter and, as shown in FIG.
Becomes a circle, which is not suitable for uniformly illuminating the rectangular imaging target surface 2. When a cylinder mirror having an elliptical cross section is used, as shown in FIG. 4B, when viewed in the elliptical cross section of FIG. 3A, light emitted from one focus Fa passes through another focus Fb. Thus, the entire area of the rectangular imaging target surface 2 can be covered, but the light is largely projected in the vertical direction (longitudinal direction), and the illumination efficiency is not good.

On the other hand, if the cross section orthogonal to the ellipse as in the present embodiment is further configured to have a parabolic cross section as shown in FIG. 3B, a rectangular image is picked up as shown in FIG. 4C. The entire area of the target surface 2 can be uniformly and efficiently illuminated.

In the image capturing device 20 of the present embodiment having the above-mentioned configuration, as shown in FIG.
An illumination light source 27 is arranged on the left side of a vertical plane C that divides the imaging target surface 2 into two substantially, and an illumination light source 27 'is arranged on the right side of the vertical plane C symmetrically with the illumination light source 27' on the left side. Only the right side of the vertical plane C of the image pickup target surface 2 is substantially illuminated by the above, and the vertical plane C (boundary line) of the image pickup target surface 2 is set by the right illumination light source 27 '. Only the left side is substantially illuminated, and the imaging target surface 2 continuously forms one imaging target area S as a whole, and the light receiving surface 5 continues as a whole. It is formed by two image pickup elements.

By doing so, the reflector 3 is emitted from the lamp 33, 33 'of the illumination light source 27, 27.
The light reflected by the umbrella ends of 4, 34 'crosses in the middle as shown by the broken line in FIG. 2, and the imaging target surface 2 (right half, left side) on the other side from the vertical plane C is crossed. Illuminate half).

Since the lights reflected by the umbrella ends of the reflecting umbrellas 14 and 14 'cross each other by the time they reach the image pickup surfaces 2 and 2', the illumination light source 27,
The reflected light from 27 'can be focused only on the imaging target surfaces 2 and 2', the illumination efficiency is improved, and the imaging target surfaces 2 and 2'can be uniformly illuminated. Further, the light receiving surface 5 is parallel to the image pickup target surface 2, and the optical axis of (the objective lens 26a of) the optical unit 26 is perpendicular to the image pickup target surface 2 (overlaps with the vertical surface 3). Therefore, it is possible to prevent the real image of the imaging target surface 2 imaged on the light receiving surface 5 by the optical unit 11 from being distorted.

Since the paint 38 as a direct light cutting means is applied to the lower part of the lamps 13 and 13 ', the direct light from the illumination light source 27 is directed to the left side of the vertical plane 3 of the image pickup symmetry plane 2. Direct light from the illumination light source 27 'is prevented from going to the right side of the vertical surface 3 of the imaging target surface 2 and the specular reflection light of the illumination light emitted from the illumination light sources 27, 27' is blocked. It can be prevented from entering the light receiving surface 5.

The image capturing device 25 and the illumination light sources 27, 27 'are rotatable about three axes (R, P, Q), and their positions and attitudes are adjusted with respect to the document table 24. Since the illumination light sources 27 and 27 'are attached to the image capturing device 25, the optimal position and orientation of the image capturing device and the illumination light sources 27 and 27' are as described above. Of the illumination light sources 27, 2 for the image capturing device 25
Since it is not necessary to adjust the position of 7 ', handling is simple and operability is improved. The illumination light sources 27, 2
7'is not necessarily attached to the image capturing device 25, and may be attached to another place such as the cover 34 or the second arm 32. Further, the positions and orientations of the illumination light sources 27 and 27 'with respect to the image capturing device 25 may be finely adjusted.

Further, the base end of the first arm 31 is pivotally supported on one end of the original table 24, and the first arm 31, the second arm 32 and the image capturing device 25 are appropriately provided. As shown in FIG. 5, the image capturing device 25 in the cover 34 and the illumination light sources 27 and 27 'can be superposed on the document table 24 by rotating, so that the device can be downsized and can be carried easily. It will be easy.

In contrast to the image capturing device 20 with an illumination light source of the above-described prerequisite embodiment, one embodiment of the image capturing device with an illumination light source according to the present invention is an image capturing optical system for a surface to be imaged, a light receiving surface, and By changing the arrangement of the illumination light source, etc.,
Other configurations, for example, the supporting form of the image capturing device having a built-in light receiving surface, the configuration of the reflector, and the like are the same as those of the above-described presumed embodiment.

That is, the image capturing apparatus 1 with an illumination light source according to the present embodiment captures an image of the document table 4 on which the image pickup target surface 2 is set and the image pickup target surface 2 as schematically shown in FIG. Light receiving surface 5, an optical unit 6 that constitutes an imaging optical system for forming a real image of the image capturing target surface 2 on the light receiving surface 5, an illumination light source 7 for illuminating the image capturing target surface 2, and the like. However, the optical unit 6, the light receiving surface 5 and the illumination light source 7 which form the image pickup optical system are provided one by one, respectively. The unit 6 is arranged on one side of the imaging target surface 2 in a plan view, that is, on the vertical surface 3 passing through one end of the imaging target surface 2, and the illumination light source 7 is positioned with respect to the imaging target surface 2. Is arranged on the same side as the optical unit 6, One, the light receiving surface 5 while being parallel to the imaging target surface 2, the optical axis of the optical unit 6 is a vertical (parallel or overlapping the vertical plane 3) to the imaging target plane.

By doing so, the entire image pickup target surface 2 (image pickup target area S) can be illuminated by one illumination light source 7, and the specular reflection light of the illumination light emitted from the illumination light source 7 is reflected on the light receiving surface 5. In addition to being able to prevent the light from entering, it is possible to prevent the real image of the imaging target surface 3 imaged on the light receiving surface 5 by the optical unit 6 from being distorted, and further by using one imaging element forming the light receiving surface 5. The entire imaging target surface 2 can be appropriately imaged.

[0025]

As can be understood from the above description, in the image capturing device with an illumination light source of the present invention, the illumination light source can be arranged in the vicinity of the image capturing means, and the regular reflection from the illumination light source is possible. It is possible to prevent light from entering the light receiving surface of the image capturing means, and moreover, it is easy to handle and has a small size.

[Brief description of drawings]

FIG. 1 is a perspective view showing a prerequisite embodiment of an image capturing device with an illumination light source according to the present invention.

FIG. 2 is an enlarged front view showing a main part of the image capturing device shown in FIG.

3A and 3B show a reflector used in the image capturing apparatus shown in FIG. 1, where FIG. 3A is a horizontal center sectional view and FIG. 3B is a vertical center sectional view.

FIG. 4 is a diagram provided for explaining the operation of a reflector used in the image capturing device shown in FIG.

FIG. 5 is a perspective view showing a stored and transported state of the image capturing device shown in FIG.

FIG. 6 is a schematic configuration diagram showing an embodiment of an image capturing device with an illumination light source according to the present invention.

FIG. 7 is a front view showing an example of a conventional image capturing device with an illumination light source.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Image capturing device with illumination light source 2 ... Imaging target surface 3 ... Vertical surface 4 ... Document table 5 ... Light receiving surface 6 ... Optical unit (imaging optical system) 7 ... Illumination light source

Claims (1)

[Claims] 1. A document table on which an image capturing target surface is set, a light receiving surface for capturing the image capturing target surface, and an image capturing optical system for forming a real image of the image capturing target surface on the light receiving surface. And an illumination light source for illuminating the imaging target surface, wherein the imaging optical system and the illumination light source are on the same side in plan view with respect to the imaging target surface and one side thereof. An image pickup device with an illumination light source, wherein the light receiving surface is parallel to the image pickup target surface, and the optical axis of the image pickup optical system is perpendicular to the image pickup target surface. Device.