JPH09211287A - Image pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate photographing operation by shortening the length of a whole device in a horizontal direction by attaching a prism body having a slant face reflecting and deflecting a luminous flux as an inside surface reflection surface on the object side of a photographing system and picking up images through the prism body. SOLUTION: The prism body 2 has the slant face 2b as a reflection surface and is provided on the object side of the photographing system 101 on an optical axis. The luminous flux from an object 1 on the optical axis 102 is made incident from an incident plane 2a constituted of a plane, and is reflected and deflected by 90 degrees by the slant face 2b and is emitted from a light exit surface 2c constituted of the plane. The luminous flux in the horizontal direction equivalent to the optical axis 102 from the object 1 is made incident from the incident plane 2a of the prism body 2, and is reflected and deflected by 90 degrees (perpendicular direction) by the reflection surface 2b, and is emitted from the light exit surface 2c and is made incident on the photographing system 101. Then, a subject image is formed on the surface of an image pickup means 7 by the photographing system 101. Thus, a photographing luminous flux is deflected by 90 degrees, so that it is made thin in the horizontal direction when it is attached at a camera main body by shortening the length in the horizontal direction as the photographing system.

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 example, in a video camera or a 35 mm film camera, the photographing direction of the photographer and the object direction (the normal direction of the image pickup means surface and the object direction) have a predetermined angle. And set
This is intended to reduce the size of the entire device.

[0002]

2. Description of the Related Art In a conventional image pickup device such as a video camera or a 35 mm film camera, when a photographing system is held in a horizontal direction, a subject is located on the front side of the optical axis of the photographing system and rearward on the optical axis of the photographing system. The image pickup surface is positioned. That is, the subject, the photographing system, and the imaging surface are arranged on a straight line.

[0003]

Conventionally, there has been a demand for a miniaturized image pickup device. However, in an image pickup apparatus configured such that the subject, the image pickup system, and the image pickup surface are located on a straight line, the solid-state image pickup element is mounted from the optical total length of the image pickup system and the image pickup surface even if the horizontal length of the entire image pickup apparatus is shortest. It is the sum of the distances to the back of the electrical board.

If the main optical system of the photographing system has a moving lens group (focus lens group) for zooming and focusing, it is necessary to move the moving lens group forward and backward in the optical axis direction by electrical means. There is. In that case, usually an actuator such as a stepping motor must be mounted, so that the horizontal direction of the entire device further projects beyond the back surface of the mounting substrate of the solid-state image sensor, and as a result, the horizontal direction of the image sensor is detected. The total length in the direction increases further.

When this image pickup apparatus is mounted in a main body such as a video camera, the length in the direction connecting the subject and the image pickup system (objective lens) increases, and it is very difficult to downsize the entire apparatus. There was a problem that

It is an object of the present invention to provide an image pickup apparatus in which the length of the entire apparatus in the horizontal direction is shortened and the photographing operation is facilitated.

[0007]

In the image pickup apparatus of the present invention, (1-1) a prism body having a slant surface for reflecting and deflecting a light beam as an inner reflection surface is attached to the object side of an image pickup system, and the prism body is interposed therebetween. The feature is that the image is captured.

In particular, (1-1-1) an inclined surface for reflecting and deflecting a light beam in an optical path of a photographing system is used as an inner reflection surface, and a prism body having a refractive power is attached to a light incident surface and / or a light exit surface. , The image is taken through the prism body.

(1-1-2) The light incident surface and / or the light exit surface of the prism body having the structure (1-1) has a refracting power.

(1-1-3) A light-shielding mask is provided near the light entrance surface and / or the light exit surface of the prism body.

(1-1-4) The opening shape of the light-shielding mask is substantially similar to the light-receiving surface shape of the image pickup means.

(1-1-5) The lens groups provided on the object side and the image plane side of the prism body are moved on the optical axis to perform zooming.

(1-1-6) The prism body reflects and deflects the light beam on the optical axis of the photographing system by 90 degrees.
And so on.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a sectional view of the essential parts of a first embodiment of the present invention. In the figure, 1 is a subject. Reference numeral 101 denotes a photographing system, which is arranged with its optical axis 102 oriented in a vertical direction V orthogonal to the horizontal direction H. Reference numeral 2 denotes a prism body, which is provided on the object side on the optical axis of the photographing system 101, with the inclined surface 2b serving as a reflecting surface. And the optical axis 10 from the subject 1
The light flux on 2 is made incident from a plane incident surface 2a, and is reflected and deflected by 90 degrees at an inclined surface 2b to form a plane emission surface 2c.
I am making it eject more.

Although the projection optical path is bent 90 degrees by the prism body 2 in this embodiment, it is not necessarily 90 degrees, and the angle of the slope 2b may be adjusted to other than 90 degrees.

Reference numeral 8 is a prism cover, which is a prism body 2.
Is pressed in the direction of the prism frame 9 to prevent dust and light. The prism frame 9 holds the prism body 2.
The imaging system 101 includes a fixed lens group 3 held by a fixed barrel 10, a zoom lens group 4 held by a moving ring 11, a fixed lens group 5 held by an afocal ring 12, and a moving ring. The rear focus type zoom lens is composed of four lens groups, namely, the lens group 6 that moves on the optical axis in order to correct and focus the image plane variation due to the magnification change, which is held in the lens unit 13. Reference numeral 14 denotes a relay holder, which holds the afocal ring 12 and is connected and fixed to the fixed lens barrel 10.

Reference numeral 7 denotes an image pickup means, which is composed of a CCD (solid-state image pickup device) or the like, and is located on the image forming plane of the image pickup system 101. Reference numeral 15 denotes a CCD holder, which includes the image pickup means 7. Reference numeral 16 is an electrical equipment substrate, which is connected to the image pickup means 7 and CC.
The D holder 15 is fixed and held, and the relay holder 1
It is fixed to the end of No. 4. Reference numeral 17 denotes a focus motor, which drives the focusing lens group 6 in the optical axis direction. A lens group 4 and a lens group 6 are motorized (not shown).
It is moved in and zoomed.

FIG. 4 is a sectional view taken along line AA of FIG. The prism frame 9 has a rectangular opening 9 that is substantially similar to the light receiving surface of the image pickup means 7.
a, and the relative positions of the sides of the rectangle are aligned. Reference numeral 9b denotes a light blocking plate (light blocking mask), which has a function of blocking a light beam other than the effective light beam of the prism body 2.
It is integrally molded with. The light shield plate 9b may be formed separately from the prism frame 9. Further, a light shielding plate may be arranged on the incident surface 2a side of the prism body 2 or between the lens group 3 and the lens group 4.

In this embodiment, the optical axis 102 from the subject 1
Is a light beam in the horizontal direction corresponding to the incident surface 2a of the prism body 2.
The light is further incident, is reflected and deflected in the 90 degree direction (vertical direction) on the reflection surface 2b, and is emitted from the emission surface 2c, and the photographing system 101
Incident on The image pickup system 101 is used by the image pickup system 101
A subject image is formed on the surface. In this way, the prism body 2 is arranged in front of the photographing system 101 and the photographing luminous flux is deflected by 90 degrees, so that the horizontal length of the photographing system is shortened and the horizontal direction when the camera body is mounted is thinned. ing.

Further, since the prism body is used for deflecting the photographing light beam without using the plane mirror, it is possible to reduce or eliminate the ghost caused by the light having a large incident angle.

FIG. 2 is a sectional view of the essential portions of Embodiment 2 of the present invention. 2, the same elements as those shown in FIG. 1 are designated by the same reference numerals.

In this embodiment, the fixed lens group 3 is eliminated as compared with the first embodiment of FIG. 1, and instead the refracting power of the lens group 3 is shared by the entrance surface 3a and the exit surface 3c of the prism body 3. The difference is that the prism body 18 having a refractive power is used, and the prism body 18 is pressed against the prism frame 9 by a part of the fixed lens barrel 10, and the other configurations are the same.

In this embodiment, the same effect as that of the first embodiment is obtained by the above-mentioned configuration.

FIG. 3 is a sectional view of the essential portions of Embodiment 3 of the present invention. 3, the same elements as those shown in FIG. 1 are designated by the same reference numerals.

This embodiment is different from Embodiment 1 in FIG. 1 in that the prism body provided on the front side of the optical axis of the photographing system 101 is eliminated,
Instead, a fixed lens group 5 is used to divide the refracting power into the entrance surface and the exit surface, respectively, and is composed of a prism body 19 having a refracting power with an inclined surface as a reflecting surface. And that the optical path is reflected and deflected by 90 degrees, and the other configurations are the same.

In the present embodiment, the lens groups 4 and 6 are moved on the optical axis to change the magnification. In FIG. 3, reference numeral 20 denotes a prism cover that presses the prism body 19 against the fixed lens barrel 10 and the relay holder 14, and also protects against dust and light. A zoom motor 21 drives the lens group 4 in the optical axis direction.

In the present embodiment, the thickness of the photographing system, and hence the camera in the horizontal direction, is reduced by the above-mentioned configuration.

[0028]

As described above, according to the present invention, it is possible to achieve the image pickup apparatus in which the horizontal length of the entire apparatus is shortened and the photographing operation is facilitated.

[Brief description of drawings]

FIG. 1 is a sectional view of a main part according to a first embodiment of the present invention.

FIG. 2 is a sectional view of an essential part of a second embodiment of the present invention.

FIG. 3 is a sectional view of an essential part of a third embodiment of the present invention.

4 is a sectional view taken along line AA of FIG.

[Explanation of symbols]

 1 subject 2, 18, 19 prism body 101 imaging system 7 imaging means 9b light-shielding mask

Claims (7)

[Claims] 1. An image pickup apparatus, comprising: a prism body having a slanted surface for reflecting and deflecting a light beam as an inner reflection surface, which is mounted on the object side of a photographing system, and picking up an image through the prism body. 2. A prism body having an inclined surface for reflecting and deflecting a light beam in an optical path of a photographing system as an inner reflection surface and having a refracting power on a light incident surface and / or a light exit surface is mounted through the prism body. An imaging device characterized by being imaging. 3. The light entrance surface and / or the light exit surface of the prism body has a refracting power.
Imaging device. 4. The image pickup device according to claim 1, wherein a light-shielding mask is provided in the vicinity of the light entrance surface and / or the light exit surface of the prism body. 5. The image pickup apparatus according to claim 4, wherein an opening shape of the light shielding mask is substantially similar to a light receiving surface shape of the image pickup means. 6. The image pickup apparatus according to claim 2, wherein the lens units provided on the object side and the image plane side of the prism body are moved on the optical axis to perform zooming. 7. The image pickup apparatus according to claim 1, wherein the prism body reflects and deflects a light beam on the optical axis of the photographing system by 90 degrees.