JPH1055023A - Camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a constitution related to a finder optical system compact, with a simple constitution capable of reducing an operating part and further, executing operation with a small force. SOLUTION: At the time of executing photographing, a light beam made incident on a photographic lens system 1 from an object passes through the semi-permeable membrane 2a of a filter member 2 perpendicular to an optical axis and reaches a CCD(charge coupled device) image pickup element 3. The photographic lens system 1 forms an object optical image on the input surface of the CCD image pickup element 3. A luminous flux from the object is decayed in a high frequency component and removed in an infrared wave length component, by the filter member 2 and then, made incident on the CCD image pickup element 3. This element 3 temporarily stores optical information received by the input surface, as image information, to output the optical information as electrical image information. At the time of observing the object, the light beam made incident on the photographic lens system 1 from the object is reflected to a side by the semi-permeable membrane 2a of the filter member 2 inclined at an angle of about 45 deg. to the optical axis and guided to a finder eyepiece optical system 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a finder optical system in a camera, and more particularly to a finder structure suitable for an electronic camera for recording image information obtained by an image pickup device such as a solid-state image pickup device on a recording medium. About the camera.

[0002]

2. Description of the Related Art In recent years, a digital camera or the like is used, and a subject image is captured by a solid-state image sensor such as a CCD (Charge Coupled Device) image sensor, and a still image (still image) or a moving image (movie image) of the object is captured. 2. Description of the Related Art Cameras of the type that obtains image data of (1) and digitally records the data on an IC (integrated circuit) card or a video floppy disk are rapidly spreading. In this case, the IC card is a PCMCIA (Personal Computer Memory Card In).
PC cards, which are IC cards conforming to the ternational Association (PC Memory Card International Association) standard, are generally used.

[0003] This type of digital camera includes the components and components of a conventional camera using a silver halide film, ie, the body and optical system of a single-lens reflex camera (single-lens reflex camera) of a silver halide camera. There are a relatively large one incorporated therein and a relatively small one corresponding to a rangefinder-lens shutter type compact camera in a silver halide camera.

[0004]

By the way, as a camera for consumer use, miniaturization is an essential condition. In terms of miniaturization, the latter type, that is, a type corresponding to a compact camera in a silver halide camera is advantageous. However, even if it is a type corresponding to a compact camera, if the taking lens system and the finder lens system are separately configured, a large space for the finder optical system is required.

As a finder system for confirming a photographing range in an electronic camera such as this digital camera which performs electronic image pickup and recording, conventionally, an optical view finder having an optical view finder or a solid-state image pickup has been used. An electronic monitor finder that displays an image captured by an element on a liquid crystal display or the like is generally used. The above two conventional systems, namely, the optical viewfinder and the electronic monitor finder, have the following disadvantages.

First, the former, that is, the drawback of the optical finder, has the following two points. (a) A finder optical system separate from the taking lens system is required.Especially, if a zoom lens is used for the taking lens system, a zoom lens must be configured in the finder optical system, and the number of lenses is large. At the same time, the zoom operation mechanism and the like become complicated, and the required manufacturing cost and the space occupied by the finder optical system increase. (b) Plastic lenses are often used for the lenses that make up the viewfinder optical system in terms of cost, but they have a lower refractive index and a longer overall length as a lens system than the lenses that make up the photographic lens system. Become. In addition, since the viewfinder optical system further requires an eyepiece lens system, the dimensions are further increased in terms of configuration.

Next, the latter, that is, the drawback of the electronic monitor finder, has the following three points. (a) A liquid crystal display for viewfinder display is required,
Including its driver circuit and backlight section,
Manufacturing costs increase. (b) Also, the above-described parts such as the driver circuit and the backlight part occupy a large weight in space. In particular, a large liquid crystal screen is required to make the display easy to see and to be able to observe from the outside, so that a larger space is required.

(C) The power consumption of a liquid crystal display and a backlight is large, and a large-capacity power supply, that is, a battery is required to constitute a camera. For this reason, the size and weight of the power supply unit increase, which imposes a heavy burden on a camera that attaches importance to portability. Also, for example, see
In JP-A-10-101534, a pentagonal roof prism widely used in a single-lens reflex camera (single-lens reflex camera) using a conventional silver halide film (hereinafter, simply abbreviated as “pentadach prism”) is used as an electronic camera. When an optical finder optical system is constructed, it is difficult to obtain the same field ratio and field magnification as those of the single-lens reflex camera for the following reasons, and it is difficult to reduce the size of the entire apparatus. It is pointed out that there is.

(A) In general, the effective screen of a solid-state imaging device such as a CCD imaging device is as small as about one-fourth of a conventional 35 mm silver halide film, and a finder optical system using the penta roof prism is used. If the optical path length is made too large, the optical path length becomes too long, and it is difficult to obtain a high field rate and a high field magnification. (b) A lot of space is required behind the solid-state imaging device for arranging the electrical processing circuit system, and the distance from the image plane of the photographing lens system to the rearmost end of the camera becomes longer. For this reason, the pupil position of the finder optical system must be extended to the rear side of the camera, which makes it difficult to obtain a high field rate and a high field magnification.

(C) a low-pass filter for attenuating a high-frequency component of an imaging light beam guided by a photographic lens system, an infrared light cut filter for cutting an infrared wavelength component of incident light, in front of the solid-state imaging device; In addition, an optical member such as a protective glass must be disposed, and a space for the optical member is required. Therefore, the distance between the image plane (subject image forming plane) and the branch point where the finder optical path branches from the imaging optical path of the imaging lens system and the finder optical path must be increased, and the entire apparatus becomes larger. I do.

In Japanese Patent Application Laid-Open No. 1-1101534, in order to solve the above-mentioned problem, in an electronic camera, the low-pass filter and the infrared cut filter described above are held in front of the image plane (subject image forming plane). A configuration in which a reflex mirror for branching an optical path, that is, a quick return mirror is arranged is disclosed. However, also in this case, in consideration of the fact that the quick return mirror operates in front of the low-pass filter and the infrared cut filter, the back focus of the photographing lens system must be lengthened, and the size of the camera increases. It is difficult to control.

In order to make this type of electronic camera more compact, it has been considered to realize a miniaturization by sharing the taking lens system with the objective lens portion of the finder lens system. However, unlike a silver halide camera, an electronic camera such as a digital camera cuts a low-pass filter for attenuating high-frequency components and cuts an infrared wavelength component of incident light between a photographic lens system and an image plane. Since the infrared light cut filter is disposed, it is not possible to make the whole compact and to dispose a quick return mirror or its equivalent in a silver halide camera.

Therefore, the applicant of the present invention firstly provided a filter member having a low-pass filter and an infrared light cut filter integrally formed, and a mirror for guiding light from the photographing lens system to the finder eyepiece optical system. A camera is proposed which is inserted alternately between the system and the image plane. That is,
By linking the filter member and the mirror,
While retracting the mirror from the imaging optical path, inserting the filter member into the imaging optical path, when observing the subject,
The filter member is retracted from the photographing optical path, and the mirror is inserted into the photographing optical path.

In this case, only one of the filter member and the mirror is arranged between the taking lens system and the image plane, so that the whole can be made compact. However, when a large-scale mechanism for moving the filter member and the mirror is required, or when performing autofocus control using an image detection signal of an image sensor at the time of subject observation,
At least a part of the mirror is composed of a half mirror (semi-transparent mirror), and the equivalent glass for adjusting the optical characteristics at the time of inserting the mirror to the state at the time of inserting the filter member must be provided behind the mirror. Become

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and has a simple structure that has a small number of operating parts and can be operated with a small driving force. It is another object of the present invention to provide a camera that can be expected to operate stably and reliably. It is an object of the present invention to provide a camera capable of guiding a subject light beam from a taking lens system to a finder eyepiece optical system with a compact and simple structure.

A second object of the present invention is to provide a camera which can effectively utilize the amount of light for photographing and guide the subject light beam from the photographing lens system to the finder eyepiece optical system with a simple structure. is there. It is an object of the present invention to provide a camera capable of guiding a subject light beam from a photographing lens system to a finder eyepiece optical system with a simple structure without loss of photographing light amount. It is an object of the present invention to provide a camera capable of guiding a subject light beam from a photographing lens system to a finder eyepiece optical system with a simple structure.

[0017]

According to the first aspect of the present invention, there is provided a camera, comprising: a photographing lens system for forming an optical image of a subject; An image sensor arranged on the image plane of the optical image for imaging the subject optical image; and a low-pass arranged between the photographing lens system and the image sensor to attenuate a high-frequency component of a light beam guided by the photographing lens system. A filter and an infrared light cut filter that cuts an infrared wavelength component of incident light are integrally formed, and a filter member having a semi-permeable film formed on a surface on the photographing lens system side; When observing a subject, the filter member is inclined at an angle of approximately 45 degrees with respect to the optical axis to reflect a light beam from the photographing lens system and guide it to the side. Drive control means for passing the light flux from the photographing lens system as it is so as to intersect the optical axis perpendicularly and guiding the light flux to the image sensor, and reflected by the semi-permeable membrane of the filter member at the time of the subject observation. And a finder eyepiece optical system for forming an observation subject image using a light beam guided to the side.

The camera according to the invention described in claim 2 is
To achieve the above-described object, a photographic lens system for forming a subject optical image, and an imaging device that is arranged on an imaging surface of the subject optical image by the photographic lens system and captures the subject optical image, A low-pass filter that is disposed between the photographing lens system and the image sensor and attenuates a high-frequency component of a light beam guided by the photographing lens system, and an infrared light cut filter that cuts an infrared wavelength component of incident light is integrally formed. A filter member, a reflection surface is formed, a plate-shaped member inserted and arranged along the surface of the filter member on the photographing lens system side when observing a subject, and the plate-shaped member and the filter member are driven; At the time of subject observation, the filter member is inclined at approximately 45 ° with respect to the optical axis, and the plate-like member is placed on a surface of the filter member on the photographic lens system side in a photographic optical path. As described above, the light from the photographic lens system is reflected and guided to the side, and at the time of photographing, the filter member is made to intersect perpendicularly with the optical axis and the plate member is moved from the photographic optical path. Drive control means for retracting and passing the light beam from the photographing lens system as it is to guide it to the image sensor, and using the light beam reflected by the plate member and guided to the side during the observation of the subject A finder eyepiece optical system that forms an observation subject image.

The camera according to the invention described in claim 3 is
To achieve the above-described object, a photographic lens system for forming a subject optical image, and an imaging device that is arranged on an imaging surface of the subject optical image by the photographic lens system and captures the subject optical image, A low-pass filter that is disposed between the photographing lens system and the image sensor and attenuates a high-frequency component of a light beam guided by the photographing lens system, and an infrared light cut filter that cuts an infrared wavelength component of incident light is integrally formed. A right-angle prism member inserted and arranged along the surface of the filter member on the photographing lens system side to form a reflection surface when observing the object, driving the right-angle prism member and the filter member, and At the time of observation, the filter member is tilted at approximately 45 ° with respect to the optical axis, and the right-angle prism member is inserted into a photographing optical path to allow the photographing lens to move. While reflecting the light beam from the system and guiding it to the side, at the time of photographing, the filter member is made to intersect perpendicularly with the optical axis, and the right-angle prism member is retracted from the photographing optical path, so that Drive control means for passing a light beam as it is and guiding it to the image pickup element, and a finder eyepiece for forming an observation subject image using the light beam reflected by the right-angle prism member and guided to the side during the object observation And an optical system.

According to a fourth aspect of the present invention, in order to achieve the above-mentioned object, the drive control means includes:
It is characterized in that it includes means for rotating the filter member about an axis including an intersection of the optical axis with the surface facing the taking lens system.

[0021]

The camera according to the first aspect of the present invention comprises a low-pass filter for attenuating a high-frequency component of a light beam guided by the photographic lens system and an infrared wavelength component of incident light between the photographic lens system and the image sensor. An infrared light cut filter for cutting is integrally formed, and a filter member formed by applying a semi-permeable membrane to a surface on the photographing lens system side is arranged,
At the time of subject observation, the filter member is tilted by approximately 45 ° with respect to the optical axis to reflect the light beam from the photographing lens system to the side, and to the finder eyepiece optical system for forming an image of the subject for observation. In some cases, the filter member is driven so that the light beam from the photographing lens system passes as it is and is guided to the image pickup device so that the optical axis intersects perpendicularly with the optical axis.

With such a configuration, the subject light beam can be formed with a simple and compact configuration in which a semipermeable membrane is applied to the filter member and the inclination angle of the filter member with respect to the optical axis is changed between 45 ° and 90 °. It can be guided from the taking lens system to the finder eyepiece optical system, and can be operated stably and reliably with a small number of operating parts and a small driving force.

According to a second aspect of the present invention, there is provided a camera, wherein a low-pass filter for attenuating a high-frequency component of a light beam guided by the photographing lens system and an infrared wavelength component of incident light are provided between the photographing lens system and the image sensor. A filter member integrally formed with an infrared light cut filter that cuts light, and at the time of observing an object, inclines the filter member by approximately 45 ° with respect to the optical axis and sets a surface of the filter member on the photographing lens system side. A plate-like member having a reflecting surface is inserted along the photographic optical path, and the light beam from the photographic lens system is reflected to the side, and guided to a finder eyepiece optical system that forms a subject image for observation. The plate member is retracted from the photographing optical path, and the light beam from the photographing lens system passes as it is so that the filter member intersects perpendicularly with the optical axis. It was driven to direct the imaging device.

With this structure, the inclination angle of the filter member with respect to the optical axis is changed between 45 ° and 90 °, and the plate member is inserted and retracted along the surface of the filter member on the photographing lens system side. With the simple configuration described above, the subject light beam can be effectively guided from the photographing lens system to the finder eyepiece optical system, and can be operated stably and reliably with a small driving force.

According to a third aspect of the present invention, there is provided a camera between a photographing lens system and an image pickup device, a low-pass filter for attenuating a high-frequency component of a light beam guided by the photographing lens system, and cutting an infrared wavelength component of incident light. A filter member integrally formed with an infrared light cut filter to be arranged, and when observing a subject, the filter member is set at approximately 45 ° with respect to the optical axis.
A finder that inclines and inserts a right-angle prism member into a photographic optical path along a surface of the filter member on the photographic lens system side, and reflects a light beam from the photographic lens system to the side to form an observation subject image. In addition to guiding to the eyepiece optical system, at the time of photographing, the right-angle prism member is retracted from the photographing optical path, and the light beam from the photographing lens system is passed as it is so as to intersect the filter member at right angles to the optical axis. It is driven to lead to the element.

With this configuration, the inclination angle of the filter member with respect to the optical axis is changed between 45 ° and 90 °, and the right-angle prism member is inserted and retracted along the surface of the filter member on the photographing lens system side. With the simple configuration described above, the subject light beam can be guided from the photographing lens system to the finder eyepiece optical system without loss of light amount, and can be operated stably and reliably with a small driving force.

According to a fourth aspect of the present invention, the tilt angle with respect to the optical axis is set to 45 ° by rotating the filter member about a straight line including the intersection of the optical axis with the surface facing the taking lens system. And 90 °. With such a configuration, the inclination angle of the filter member with respect to the optical axis can be changed with a particularly simple configuration, and the operation can be stably and reliably performed with a smaller driving force.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a camera according to the present invention will be described in detail based on embodiments with reference to the drawings. 1 to 3 show a configuration of a main part of a camera according to a first embodiment of the present invention. FIG. 1 is a perspective view schematically illustrating the entire configuration of a main optical system of a camera related to photographing and a viewfinder, FIG. 2 is a side view schematically illustrating the optical system when observing a subject, and FIG. FIG. 2 is a perspective view schematically showing a photographing optical system at the time of photographing.

The camera shown in FIG. 1 includes a photographing lens system 1, a filter member 2, a CCD image pickup device 3, a finder eyepiece optical system 4, and a drive device 5 as drive control means. The photographing lens system 1 is an optical system for forming an optical image of a subject on an input surface of the CCD image pickup device 3 based on incident light from the subject during photographing. This taking lens system 1
Also serves as an objective lens system in the finder optical system. The filter member 2 includes a low-pass filter for attenuating a high-frequency component of a light beam guided by the photographing lens system 1 and an infrared light cut filter for cutting an infrared wavelength component of incident light, and the like. It is configured integrally.

The filter member 2 is disposed between the photographing lens system 1 and the CCD image pickup device 3, and transmits part of incident light and reflects part of the incident light on the object side, that is, on the surface of the photographing lens system 1. A semi-permeable film (semi-transmissive reflective film) 2a is formed. The CCD image sensor 3 is a solid-state image sensor. The CCD image sensor 3 captures an optical image of a subject formed on an input surface by the photographing lens system 1, converts the optical image into electrical image information, and sends the electrical image information to an image information processing unit (not shown). Supply. Note that the image information processing unit
The image information given at the time of shooting is recorded on a recording medium such as a PC card or a video floppy disk. When observing the subject, the image information processing unit may detect the in-focus state using the subject light transmitted through the semi-permeable membrane 2a of the filter member 2 and provide the subject to the autofocus control.

The finder eyepiece optical system 4 includes an image inverting system 41.
And an eyepiece 42, and form a finder optical system together with the taking lens system 1 as an objective lens. The image reversing system 41 guides the subject light beam reflected by the semi-permeable membrane 2a of the filter member 2 to the eyepiece lens 42, and inverts the subject image formed by the photographing lens system 1 to an erect image. It is formed integrally.
The eyepiece lens 42 is an optical system for observing the subject optical image formed by the image reversing system 41.

In the case of this embodiment, the drive device 5 is a drive control means for controlling the drive of the filter member 2. The drive device 5 drives the semi-permeable membrane 2 a of the filter member 2 in conjunction with camera operation such as subject observation and photographing. The rotation of the filter member 2 is controlled with a straight line including the intersection between the surface and the optical axis as the axis. That is, under the control of the driving device 5, when observing the subject,
As shown in FIGS. 1 and 2, the filter member 2 is set at an angle of approximately 45 ° with respect to the optical axis.
As shown in (2), the filter member 2 is set in a state where the optical axis intersects vertically.

Next, a specific operation of the camera configured as described above will be described. As described above, the filter member 2 is driven by the driving device 5 and is orthogonal to the optical axis at the time of photographing, and is inclined by approximately 45 ° with respect to the optical axis at the time of observing a subject. Therefore, at the time of photographing, a light beam incident on the photographing lens system 1 from the subject passes through the semi-permeable membrane 2a of the filter member 2 orthogonal to the optical axis as shown in FIG. Reach 3. The taking lens system 1 forms an optical image of a subject on an input surface of the CCD image sensor 3. As described above, since the filter member 2 is a combination of the low-pass filter and the infrared light cut filter, the luminous flux from the subject is attenuated by the filter member 2 in the high frequency component and the infrared wavelength component is removed. Then, the light enters the CCD image sensor 3.

The CCD image sensor 3 temporarily stores the optical information received on the input surface as image information, outputs it as electrical image information, and sends it to the above-described image information processing unit (not shown). Supply. At the time of observing the subject, the light rays incident on the photographing lens system 1 from the subject are laterally reflected by the semi-permeable membrane 2a of the filter member 2 inclined at approximately 45 ° with respect to the optical axis as shown in FIGS. Is introduced into the finder eyepiece optical system 4. The finder eyepiece optical system 4
The incident subject light beam is guided by the image reversing system 41, and the inverted subject image formed by the photographing lens system 1 is reversed so that the user can observe the upright subject image via the eyepiece lens. .

Note that the CCD image pickup device 3 uses a subject light beam transmitted through the semi-permeable membrane 2a of the filter member 2 when observing the subject.
Focus detection may be performed based on the image information described above, and at least one of the photographing lens system 1 and the CCD image sensor 3 may be moved along the optical axis to perform autofocus control. In this case, the filter member 2 is not relevant at the time of observing the subject, but at the time of photographing, the optical path length differs by an amount corresponding to the passage of the filter member 2 for inserting the filter member 2 into the imaging optical path. There is a possibility that an error, that is, a shift of a subject image position may occur. Since these errors in the image plane or the displacement of the object image position can be predicted in advance by calculation and measured by experiments, if they have a size that cannot be ignored, the photographing lens system may be used as necessary. 1 and at least one of the CCD image pickup devices 3 can be driven for correction, or can be subjected to correction processing by an image information processing unit.

FIG. 4 is a side view schematically showing a configuration of a main part of a camera according to a second embodiment of the present invention, and schematically showing an optical system for observing a subject. The camera shown in FIG.
A photographing lens system 1 and a CCD image pickup device 3 similar to those shown in FIGS.
And a finder eyepiece optical system 4. Also,
The camera shown in FIG. 4 has a filter member 6 and a drive device 7 slightly different from the filter member 2 and the drive device 5 of FIGS. 1 to 3, and further includes a plate-like member 8.

The filter member 6 includes a low-pass filter for attenuating a high-frequency component of a light beam guided by the taking lens system 1 and an infrared light cut filter for cutting an infrared wavelength component of incident light. And are integrally configured. This filter member 6 is provided between the photographing lens system 1 and C
It is arranged between the image pickup device 3 and the CD. That is, the filter member 6 is obtained by removing the semipermeable membrane 2a from the filter member 2 shown in FIGS.

The plate member 8 is provided in place of the semipermeable membrane 2a of the filter member 2 shown in FIGS. 1 to 3, and is provided between the photographing lens system 1 and the filter member 6 when observing a subject. 6 is inserted along the surface of the object side, that is, the photographing lens system 1 side, and almost overlaps with the surface. A reflection film is formed on the plate-like member 8 on the photographing lens system 6 side, that is, on the reflection side surface of the filter member 6, and totally reflects incident light. Therefore, this plate member 8
Are configured as a kind of mirror.

The drive device 7 is a drive control means for controlling the drive of the filter member 6 and the plate member 8. Drive 7
Is linked to camera operations such as subject observation and shooting,
The rotation of the filter member 6 is controlled with a straight line including the intersection of the surface of the filter member 6 on the side of the photographing lens system 1 and the optical axis as the axis, and the plate member 8 enters the photographing optical path in conjunction with the rotation control. Drive control is performed so as to retract. That is,
Under the control of the driving device 7, when observing the subject, FIG.
The filter member 6 is set at approximately 45 ° with respect to the optical axis as shown in FIG.
The plate member 8 is set to be inclined, and is inserted into the photographing optical path in a state where the plate member 8 extends along the surface of the filter member 6 on the photographing lens system 1 side and almost in close contact. Also,
Under the control of the driving device 7, the filter member 6
Prior to setting to a state perpendicular to the optical axis, the plate member 8 is retracted out of the imaging optical path.

Next, a specific operation of the camera thus configured will be described. As described above, the filter member 6
The plate-like member 8 is driven by a driving device 7 so that the plate-like member 8 retracts first during photographing, the filter member 6 continues to rotate so as to be orthogonal to the optical axis, and the filter member 6 The plate member 8 is inserted into the photographing optical path while being inclined to approximately 45 ° with respect to the optical axis. Therefore, at the time of photographing, the light beam incident on the photographing lens system 1 from the subject is
The light reaches the CCD image sensor 3 through a filter member 6 orthogonal to the optical axis. The luminous flux from the subject enters the CCD image sensor 3 after the high-frequency component is attenuated and the infrared wavelength component is removed by the filter member 6. CCD image sensor 3
Temporarily stores optical information received on the input surface as image information and supplies it as electrical image information to an image information processing unit (not shown).

At the time of observing the subject, a light beam incident on the photographing lens system 1 from the subject is reflected laterally (or upward) by the reflecting film of the plate member 8 inclined at approximately 45 ° with respect to the optical axis. The light is introduced into the eyepiece optical system 4. If a semi-permeable film is used in place of the reflective film of the plate member 8, focus detection is performed based on the image information of the CCD image pickup device 3 based on the subject light flux transmitted through the semi-permeable film, and the photographing lens system 1 and the CCD imaging device are used. At least one of the elements 3 may be moved along the optical axis to perform autofocus control.

FIG. 5 is a side view schematically showing an essential part of a camera according to a third embodiment of the present invention, and schematically showing an optical system for observing a subject. The camera shown in FIG.
4 includes a photographing lens system 1, a CCD image pickup device 3, a finder eyepiece optical system 4, and a filter member 6 similar to those in FIG. Further, the camera shown in FIG. 5 has a drive device 7A as drive control means slightly different from the drive device 7 of FIG.
Further, a right-angle prism 9 is provided in place of the plate member 8 in FIG.

The right-angle prism 9 is provided in place of the plate-like member 8 in FIG. 4, and is provided between the photographing lens system 1 and the filter member 6 as shown in FIG. The inclined surface is inserted along the surface of the filter member 6 on the subject side, that is, on the photographing lens system 1 side, and is almost in close contact therewith. The right-angle prism 9 totally reflects incident light incident from the photographing lens system 1 on an inclined surface inclined at 45 ° to the optical axis. The drive device 7A is drive control means for controlling the drive of the filter member 6 and the right-angle prism 9.

The driving device 7A operates in conjunction with a camera operation such as subject observation and photographing to set a straight line including an intersection between the surface of the filter member 6 on the photographing lens system 1 side and the optical axis as an axis.
The rotation of the filter member 6 is controlled, and the driving of the plate member 9 is controlled so as to move in and out of the imaging optical path in conjunction with the rotation of the filter member 6. That is, under the control of the driving device 7A, at the time of subject observation, the filter member 6 is set to be inclined at approximately 45 ° with respect to the optical axis as shown in FIG. The right-angle prism 9 is inserted into the photographing optical path in a state shown in the drawing so as to be substantially in close contact with the surface of the photographing lens system 1. Further, under the control of the driving device 7A, at the time of photographing, the filter member 6 is set to a state where the optical axes intersect perpendicularly,
The right-angle prism 9 is retracted out of the photographing optical path.

Next, a specific operation of the camera configured as described above will be described. As described above, the filter member 6
The right-angle prism 9 is driven by a driving device 7A. At the time of photographing, the right-angle prism 9 is retracted, for example, to the side of the camera body, and the filter member 6 is orthogonal to the optical axis. And the right angle prism 9 is inserted into the photographing optical path.

Therefore, at the time of photographing, a light beam incident on the photographing lens system 1 from the subject reaches the CCD image pickup device 3 through the filter member 6 orthogonal to the optical axis. The light beam from the subject is incident on the CCD image pickup device 3 after the high frequency component is attenuated and the infrared wavelength component is removed by the filter member 2. The CCD image sensor 3 temporarily stores the optical information received on the input surface as image information and supplies it as electrical image information to an image information processing unit (not shown). At the time of observing the subject, the light beam incident on the photographing lens system 1 from the subject is approximately 45 ° with respect to the optical axis of the right-angle prism 9.
The light is reflected laterally by the inclined surface that is inclined and is introduced into the finder eyepiece optical system 4.

[0047]

As described above, according to the present invention, a low-pass filter for attenuating a high-frequency component of a light beam guided by the photographing lens system and an infrared ray of incident light are provided between the photographing lens system and the image sensor. An infrared light cut filter that cuts a wavelength component is integrally formed, and a filter member having a semi-permeable film provided on a surface on the photographing lens system side is disposed. The light beam from the photographic lens system is reflected sideways at an angle of approximately 45 ° with respect to the finder eyepiece optical system for forming an observation subject image. Since the light from the photographic lens system is driven so as to pass through as it intersects vertically and guided to the image sensor, a semipermeable membrane is applied to the filter member and the filter is provided. The inclination angle with respect to the optical axis of the member 45
With a simple and extremely compact configuration that can be changed between ° and 90 °, the light beam of the subject can be guided from the taking lens system to the finder eyepiece optical system, and it operates stably and reliably with a small number of operating parts and a small driving force. It is possible to provide a camera capable of causing the camera to operate.

According to the camera of the second aspect of the present invention, a low-pass filter for attenuating a high-frequency component of a light beam guided by the photographing lens system and an infrared ray of incident light are provided between the photographing lens system and the image pickup device. A filter member integrally formed with an infrared light cut filter that cuts a wavelength component is disposed, and at the time of observing a subject, the filter member is inclined at approximately 45 ° with respect to an optical axis and the filter member is disposed on the photographing lens system side. A plate-like member having a reflecting surface is inserted into a photographing optical path along the surface of the photographing lens, and a light beam from the photographing lens system is reflected to the side to guide to a viewfinder eyepiece optical system for forming a subject image for observation and photographing. Sometimes, the plate member is retracted from the imaging optical path, and the light beam from the imaging lens system is left as it is so that the filter member intersects perpendicularly with the optical axis. The filter member is driven so as to be guided to the image pickup device. Therefore, the inclination angle of the filter member with respect to the optical axis is changed between 45 ° and 90 °, and the plate member is changed to the surface of the filter member on the photographing lens system side. Insert along
With a simple configuration that only retracts, the subject light beam can be effectively guided from the photographing lens system to the finder eyepiece optical system, and can be operated stably and reliably with a small driving force.

According to the camera of the third aspect of the present invention, a low-pass filter for attenuating a high-frequency component of a light beam guided by the photographic lens system and an infrared wavelength component of incident light are provided between the photographic lens system and the image sensor. A filter member integrally formed with an infrared light cut filter that cuts light, and when the subject is observed, the filter member is moved approximately four times with respect to the optical axis.
A right-angle prism member is inserted into a photographing optical path along the surface of the filter member on the photographing lens system side, and the light beam from the photographing lens system is reflected sideways to form an observation subject image. Along with guiding to the finder eyepiece optical system, during photographing, the right-angle prism member is retracted from the photographing optical path and the light beam from the photographing lens system is passed as it is so that the filter member intersects perpendicularly with the optical axis. Since the filter is configured to be driven to be guided to the image sensor, the inclination angle of the filter member with respect to the optical axis is changed between 45 ° and 90 °, and the right-angle prism member is formed along the surface of the filter member on the photographing lens system side. With a simple configuration that simply inserts and retracts, the light beam from the subject can be guided from the taking lens system to the viewfinder eyepiece optical system without loss of light quantity. Possible to stably and reliably operated by the driving force to become.

According to the camera of the fourth aspect of the present invention, the tilt angle with respect to the optical axis can be reduced by rotating the filter member about a straight line including the intersection of the optical axis with the surface facing the taking lens system. Since the angle is changed between 45 ° and 90 °, the inclination angle of the filter member with respect to the optical axis can be changed with a particularly simple structure, and stable and reliable operation can be performed with a smaller driving force. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing a configuration of a main part of a camera according to a first embodiment of the present invention when observing a subject.

FIG. 2 is a side view schematically showing a configuration of an optical system of the camera of FIG. 1 when observing a subject.

FIG. 3 is a perspective view schematically showing a configuration of the camera of FIG. 1 at the time of shooting.

FIG. 4 is a side view schematically showing a configuration of a main part of a camera according to a second embodiment of the present invention.

FIG. 5 is a side view schematically showing a configuration of a main part of a camera according to a third embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photographing lens system 2, 6 filter member 2a semi-permeable membrane 3 CCD imaging device 4 finder eyepiece optical system 5, 7, 7A driving device 8 plate member 9 right angle prism 41 image reversal system 42 eyepiece

Claims (4)

[Claims] A photographing lens system for forming an optical image of a subject; an image pickup device arranged on an image forming plane of the optical image of the subject by the photographing lens system to capture the optical image of the subject; A low-pass filter that attenuates the high-frequency component of the light flux guided by the imaging lens system and an infrared light cut filter that cuts the infrared wavelength component of the incident light, which are arranged between the image sensor and the imaging element;
A filter member having a semi-permeable membrane applied to a surface on the photographic lens system side; and driving the filter member to tilt the filter member by approximately 45 ° with respect to an optical axis when observing a subject. While reflecting the light flux from
At the time of photographing, drive control means for passing the light beam from the photographing lens system as it is so as to intersect the filter member perpendicularly to the optical axis and guide the light beam to the image pickup device, A camera, comprising: a finder eyepiece optical system that forms an observation subject image using a light beam reflected by the semi-permeable film and guided to the side. 2. A photographing lens system for forming an optical image of a subject, an image sensor arranged on an image forming plane of the optical image of the subject by the photographing lens system and capturing the optical image of the subject, and the photographing lens system A filter member that is disposed between the image pickup device and a low-pass filter that attenuates high-frequency components of a light beam guided by the photographing lens system and an infrared light cut filter that cuts infrared wavelength components of incident light. A reflecting surface is formed, and a plate-shaped member inserted and arranged along a surface of the filter member on the photographing lens system side when observing a subject; and driving the plate-shaped member and the filter member, and observing a subject when observing a subject. The filter member is moved approximately 45 with respect to the optical axis.
While tilting, the plate-shaped member is inserted so as to overlap the surface of the filter member on the photographic lens system side in the photographic optical path, reflects the light beam from the photographic lens system and guides it to the side, and at the time of photographing Drive control so that the filter member intersects perpendicularly with the optical axis and the plate member is retracted from the imaging optical path so that the light beam from the imaging lens system passes as it is and is guided to the image sensor. And a finder eyepiece optical system for forming an observation subject image using a light beam reflected by the plate-like member and guided to the side during the observation of the subject. 3. A photographic lens system for forming an optical image of a subject, an imaging device arranged on an image forming plane of the optical image of the subject by the photographic lens system and capturing the optical image of the subject, and the photographic lens system A filter member that is disposed between the image pickup device and a low-pass filter that attenuates high-frequency components of a light beam guided by the photographing lens system and an infrared light cut filter that cuts infrared wavelength components of incident light. A right-angle prism member inserted and arranged along the surface of the filter member on the photographic lens system side to form a reflective surface during subject observation, and driving the right-angle prism member and the filter member, The filter member is tilted at approximately 45 ° with respect to the optical axis, and the right-angle prism member is inserted into a photographing optical path to reduce the light flux from the photographing lens system. While being reflected and guided to the side, at the time of photographing, the filter member is made to intersect perpendicularly with the optical axis, and the right-angle prism member is retracted from the photographing optical path to pass the light beam from the photographing lens system as it is. And a finder eyepiece optical system that forms an observation subject image using a light beam reflected by the right-angle prism member and guided to the side during the observation of the subject. Camera. 4. The drive control means includes means for rotating the filter member about an axis including an intersection of the optical axis with a surface facing the taking lens system. The camera according to any one of the preceding claims.