JP4837380B2 - camera - Google Patents

Description

  The present invention relates to a camera, and more particularly, to a camera provided with an imaging unit for monitoring a subject image before photographing through an electronic viewfinder, for example, in addition to an imaging unit for photographing a subject image.

Conventionally, as this type of camera, for example, those described in the following Patent Documents 1 and 2 have been proposed.
Japanese Patent Laid-Open No. 9-5866 JP 2000-165730 A

  The camera described in Patent Document 1 is provided with an optical path dividing means in the middle of an optical path for photographing a light beam from a subject that has passed through a photographing lens through a film so that an optical path is formed in a direction different from the film. An optical path bending means is provided on an optical path divided in a direction different from that of the film to divide the light beam, and an imaging element is provided on the bent optical path.

  The camera described in Patent Document 2 is provided with a first optical path changing means in the middle of an optical path for imaging a light beam from a subject that has passed through a photographing lens through the first imaging element. Second optical path changing means configured to be able to switch the optical path in different directions and to switch the optical path between the second imaging element and the optical finder on the optical path switched in a different direction from the first imaging element. And a second image sensor and an optical finder are provided on each optical path switched by the second optical path changing means.

However, in a conventional camera including an imaging unit for monitoring a subject image before photographing in addition to a photographing unit for photographing a subject image as described in Patent Documents 1 and 2, There has been a problem in that vignetting of light rays and a decrease in peripheral light amount are likely to occur at the periphery of the screen of the subject image picked up by the image pickup means used for the monitor.
In particular, in a camera equipped with both a liquid crystal finder and an optical finder using an imaging means for a monitor, it is difficult to suppress vignetting of light rays and a decrease in peripheral light quantity at the periphery of the observation screen of both the liquid crystal finder and the optical finder. . However, in the camera described in Patent Document 2 equipped with a liquid crystal finder and an optical finder, means for taking in a subject image observed through both of the finders to the periphery of the observation screen with high accuracy has been proposed. Absent.

  In addition to the photographing means for photographing the subject image as described in Patent Documents 1 and 2, a camera equipped with an imaging means for monitoring the subject image before photographing is used for monitoring. By providing the image pickup device, the number of parts increases correspondingly, resulting in an increase in cost and a tendency to increase in size.

  The present invention has been made in view of the above-described conventional problems. In a camera including an imaging unit for monitoring a subject image on an optical path different from an optical path for capturing a subject image, the periphery of the screen is provided. This makes it possible to observe the subject image with high accuracy by minimizing the vignetting of light rays and the decrease in the amount of light in the surroundings, and to efficiently lay out the components, contributing to downsizing and cost reduction. An object is to provide a camera that can be used.

To achieve the above object, the camera according to the onset bright, light between the first image pickup means, wherein said imaging lens first imaging means for imaging a subject image from the subject light flux passing through the photographing lens An optical path branching unit configured to be able to guide the subject luminous flux to an optical path toward the first imaging unit and an optical path in a direction different from the first imaging unit, and the first imaging unit; Is an optical surface provided in a finder optical system disposed on the optical path in a different direction and a part of optical elements constituting the finder optical system, from the subject light flux reflected through the optical path branching means A primary imaging plane on which a subject image is formed, and an optical path branched in a direction away from the optical path of the finder optical system in the middle of the optical path of the finder optical system; Formed into A second imaging unit that captures a subject image; a re-imaging optical system that projects the subject image formed on the primary imaging plane onto the second imaging unit; and the first or second imaging unit. with comprises an object image display means capable of displaying a subject image captured through the unit, as part of the common optical means constituting the re-imaging optical system and the viewfinder optical system, the photographing information display means and In-focus position display means is provided, and the following conditional expression (1) is satisfied.
｜ TAN ⁻¹ (OBJH / ENP1) −TAN ⁻¹ (OBJH / ENP2) | ≦ 20 °
… (1)
However, ENP1 is the distance on the optical axis from the entrance pupil of the re-imaging optical system to the subject image formed on the primary imaging plane, and ENP2 is the primary image from the entrance pupil of the finder optical system. This is the distance on the optical axis to the subject image formed on the surface. The eyepoint of the finder optical system here is an arbitrary value within a range of 0 to 50 mm from the final surface of the finder optical system toward the observation side. OBJH is the maximum effective ray height on the primary imaging plane.

Further, in this onset Ming camera, the re-imaging optical system includes at least a positive, have each one negative lens, it is desirable to satisfy the following conditional expression (2).
10 ≦ νp − νn (2)
Where νp is the Abbe number of the positive lens among the lenses constituting the re-imaging optical system, and νn is the Abbe number of the negative lens among the lenses constituting the re-imaging optical system. Is a number.

Further, in this onset Ming camera, the re-imaging optical system has at least a positive lens 2 sheets, it is desirable to satisfy the following conditional expression (3).
50 ≤ vpmx (3)
However, νpmx is the Abbe number of the positive lens having the highest power among the lenses constituting the re-imaging optical system at the d-line.

Further, in this onset Ming camera, the re-imaging optical system, the comprising at least one or more plastic lenses are preferred.

Further, in this onset Ming camera, the re-imaging optical system, the comprising at least one or more aspherical lenses is preferred.

Further, in this onset Ming camera, as compared to an imaging device used in the first imaging means, preferably the smaller the imaging device used in the second imaging means.

Further, in this onset Ming camera, in the vicinity of the primary image forming surface is a surface (e.g., a Fresnel lens surface to be described later) having a condensing function at least one of the matte surface, the one Tsugiyui It is preferable that the lens is disposed parallel to the image plane and satisfies the following conditional expression (1 ′).
｜ TAN ⁻¹ (OBJH / ENP1) −TAN ⁻¹ (OBJH / ENP2) | ≦ 15 °
… (1 ')
However, ENP1 is the distance on the optical axis from the entrance pupil of the re-imaging optical system to the subject image formed on the primary imaging plane, and ENP2 is the primary image from the entrance pupil of the finder optical system. This is the distance on the optical axis to the subject image formed on the surface. The eyepoint of the finder optical system here is an arbitrary value within a range of 0 to 50 mm from the final surface of the finder optical system toward the observation side. OBJH is the maximum effective ray height on the primary imaging plane.

Further, in this onset Ming camera, the viewfinder optical system and the re-imaging optical system comprises a plurality of optical reflection surfaces, one of said plurality of optical reflecting surface, a light-transmitting properties Is preferred.

  According to the present invention, in a camera having an imaging unit for monitoring a subject image on a different optical path from the optical path for photographing the subject image, vignetting of light rays and reduction of the peripheral light amount occurring at the periphery of the screen are reduced. For example, using a liquid crystal viewfinder (in the case of a configuration equipped with an optical viewfinder, using either a liquid crystal viewfinder or an optical viewfinder), subject observation can be performed with high accuracy, and Thus, a camera that can efficiently lay out the components and contribute to downsizing and cost reduction can be obtained.

Prior to the description of the embodiment, the function and effect of the present invention will be described.
This onset Ming camera, said a first imaging means for imaging a subject image from the subject light flux passing through the photographing lens, the subject light flux in the optical path between said imaging lens first imaging means An optical path branching unit configured to be able to guide an optical path toward the first imaging unit and an optical path in a direction different from the first imaging unit, and an optical path in a direction different from the first imaging unit An optical surface provided in the arranged finder optical system and a part of optical elements constituting the finder optical system, wherein a subject image is formed from the subject luminous flux reflected through the optical path branching means 1 A subject image formed on the primary imaging plane, and arranged on an optical path branched in a direction away from the optical path of the finder optical system in the middle of the optical path of the secondary imaging plane and the finder optical system Second imaging to image A re-imaging optical system for projecting a subject image formed on the primary imaging plane onto the second imaging unit, and a subject image captured via the first or second imaging unit with comprises an object image display means capable of displaying, as part of the common optical means constituting the re-imaging optical system and the viewfinder optical system, comprising a photographing information display means and focusing portion display unit, It is characterized by satisfying the following conditional expression (1).
｜ TAN- ¹ (OBJH / ENP1) -TAN- ¹ (OBJH / ENP2) | ≦ 20 °
… (1)
However, ENP1 is the distance on the optical axis from the entrance pupil of the re-imaging optical system to the subject image formed on the primary imaging plane, and ENP2 is the primary image from the entrance pupil of the finder optical system. This is the distance on the optical axis to the subject image formed on the surface. The eyepoint of the finder optical system here is an arbitrary value within a range of 0 to 50 mm from the final surface of the finder optical system toward the observation side. OBJH is the maximum effective ray height on the primary imaging plane.

  If the upper limit value of the conditional expression (1) is exceeded, the difference between the entrance pupil position of the finder optical system and the entrance pupil position of the re-imaging optical system projected onto the second imaging means becomes too large. Then, in the subject image observed through the finder or the subject image picked up through the second image pickup means, vignetting of the light and a significant decrease in the amount of peripheral light are likely to occur at the periphery of the screen. Practical problems such as hindering observation using the viewfinder are likely to occur.

In the present onset Ming camera, all or part of the re-imaging optical system is preferably configured to be commonly used as optical members constituting a finder optical system.
By doing so, the number of optical members for configuring the entire camera can be saved, and the camera housing can be reduced in size and cost.
As described above, the camera of the present invention includes photographing information display means and in-focus position display means as a part of common optical means constituting the finder optical system and the re-imaging optical system.
With this configuration, the number of optical members for configuring the entire camera can be saved, and the camera housing can be reduced in size and cost, while the viewfinder optical system and the re-imaging optical system can be used. In addition, the subject image data formed on the primary image plane can be confirmed, and at the same time, information such as shutter speed and Fno and the in-focus location can be confirmed through the photographing information display means and the in-focus location display means.

Further, in this onset Ming camera, the re-imaging optical system includes at least a positive, have each one negative lens, it is desirable to satisfy the following conditional expression (2).
10 ≦ νp − νn (2)
Where νp is the Abbe number of the positive lens among the lenses constituting the re-imaging optical system, and νn is the Abbe number of the negative lens among the lenses constituting the re-imaging optical system. Is a number.

  If the lower limit value of the conditional expression (2) is not reached, the achromatic effect due to the positive and negative lenses is reduced, resulting in an increase in chromatic aberration and a necessary and sufficient resolving power corresponding to the pixel pitch of the monitor display image sensor. It becomes difficult.

Further, in this onset Ming camera, the re-imaging optical system has at least a positive lens 2 sheets, it is desirable to satisfy the following conditional expression (3).
50 ≤ vpmx (3)
However, νpmx is the Abbe number of the positive lens having the highest power among the lenses constituting the re-imaging optical system at the d-line.

  If the lower limit of the conditional expression (3) is not reached, dispersion by the positive lens having the largest power increases, so that chromatic aberration increases, and a necessary and sufficient resolving power corresponding to the pixel pitch of the monitor display imaging device can be obtained. It becomes difficult.

Further, in this onset Ming camera, the re-imaging optical system, the comprising at least one or more plastic lenses are preferred.

  If a plastic lens is used, the necessary and sufficient performance can be ensured at a lower cost than when a glass lens is used.

Further, in this onset Ming camera, the re-imaging optical system, the comprising at least one or more aspherical lenses is preferred.

  If an aspherical lens is used, necessary and sufficient performance can be ensured with a small number of lenses, so that the camera housing can be reduced in size and cost.

Further, in this onset Ming camera, as compared to an imaging device used in the first imaging means, preferably the smaller the imaging device used in the second imaging means.

If a small image sensor is used, the light flux can be reduced, and the size of the camera can be reduced.
In addition, the use of a small image sensor can reduce power consumption, which is advantageous for increasing the number of images that can be taken as much as possible.
Further, the magnification by the re-imaging optical system becomes less than 1, and the principal point position of the re-imaging optical system can be on the second imaging means side, which is advantageous in layout. For example, it becomes easy to dispose a lens element such as an imaging lens for forming a subject image on the second imaging means on the optical path branched from the optical path of the finder optical system.

Further, in this onset Ming camera, in the vicinity of the primary image forming plane, at least one of the surfaces and the mat surface having a condensing function, and arranged parallel to the said primary image plane, the following It is preferable that the conditional expression (1 ′) is satisfied.
｜ TAN ⁻¹ (OBJH / ENP1) −TAN ⁻¹ (OBJH / ENP2) | ≦ 15 °
… (1 ')
However, ENP1 is the distance on the optical axis from the entrance pupil of the re-imaging optical system to the subject image formed on the primary imaging plane, and ENP2 is the primary image from the entrance pupil of the finder optical system. This is the distance on the optical axis to the subject image formed on the surface. The eyepoint of the finder optical system here is an arbitrary value within a range of 0 to 50 mm from the final surface of the finder optical system toward the observation side. OBJH is the maximum effective ray height on the primary imaging plane.

If a surface having a condensing function is arranged in the vicinity of the primary imaging surface in parallel with the primary imaging surface, aberration fluctuations can be minimized, and the subject luminous flux can be transmitted to the finder optical system and the re-imaging system. Refracting toward the respective entrance pupils of the imaging optical system, it is possible to prevent the occurrence of vignetting and a significant decrease in peripheral light quantity at the periphery of the screen of the image data acquired by the finder and the second imaging means. .
Further, if a mat surface is arranged in the vicinity of the primary image formation plane in parallel with the primary image formation surface, deterioration due to diffusion of the subject image can be minimized, and the subject light flux can be generated by diffusion of the mat surface. , Incident on each entrance pupil of the finder optical system and the re-imaging optical system, and no vignetting of the light beam or a significant decrease in peripheral light quantity occurs at the periphery of the screen of the image data acquired by the finder and the second imaging means. Can be.
Further, if the above conditional expression (1 ′) is satisfied, the difference between the entrance pupil positions of the finder optical system and each optical system as the second imaging means becomes small, and the refraction of the surface having the light condensing function and the mat surface Even if the subject luminous flux is affected by diffusion, it is possible to make it difficult to cause vignetting of the light and a significant decrease in the amount of peripheral light at the periphery of the screen of the image data acquired by the finder and the second imaging means.

Further, in this onset Ming camera, the viewfinder optical system and the re-imaging optical system comprises a plurality of optical reflection surfaces, one of said plurality of optical reflecting surface, a light-transmitting properties Is preferred.

  If comprised in this way, the to-be-photographed object image reversed with the imaging lens can be made into an erect image through an optical path branching means and a plurality of optical reflecting surfaces. In addition, if any of the plurality of optical reflecting surfaces has a light transmission characteristic, a part of the optical path is shared in the middle so that the finder optical system and the second imaging unit can be arranged in a compact manner. The optical path can be branched.

The present onset in Ming camera, pre Symbol finder optical system in the middle in the second second switchable to the optical path to the optical path toward the final surface of the finder optical system toward the imaging means of the optical path branching optical paths The display operation of the imaging information display unit and the in-focus position display unit is turned off when the optical path to the second imaging unit is switched via the second optical path branching unit. It is preferable to do this.

When switching to the optical path toward the second image pickup means, the display operation of the shooting information display means and the in-focus position display means must be turned on to add the shooting information, the in-focus position, etc. to the subject image before shooting. In addition, it is possible to display or record an image by adding desired information to the subject image captured through the second imaging unit using a known image processing unit.
Therefore, if the display operation of the photographing information display means and the in-focus position display means is turned off when the optical path toward the second imaging means is switched, power consumption can be saved correspondingly.

In general, an optical finder (OVF) can be premised on a focus adjustment function of a human eye. For this reason, in the finder optical system in the camera as in the present invention, it is possible to increase the allowable amount of positional deviation between the screen mat, the photographing information display means, and the in-focus location display means.
Therefore, if the display operation of the photographing information display means and the in-focus position display means is turned off when the optical path to the second image pickup means is switched, the arrangement of the photographing information display means and the in-focus position display means is arranged. Can be designed on the optical path used as an optical finder having a large allowable amount of positional deviation, so that the arrangement of the photographing information display means and the in-focus position display means becomes easy, which is advantageous for layout design and assembly.

  The photographing information display means and the in-focus position display means in the camera of the present invention are display means arranged for the optical viewfinder. The photographing information display means has a function of displaying information such as the shutter speed, Fno, and the remaining number of images that can be photographed at the edge of the subject image or outside. The in-focus location display means displays a position to be focused or a position in focus among a plurality of in-focus setting points (multi-point distance measurement). It has a function to present the mark again.

(First embodiment)
Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram showing an arrangement relationship of optical members at the time of subject observation before photographing in the camera according to the first embodiment of the present invention, and FIG. 2 shows an arrangement relationship of optical members at the time of subject photographing in the camera of FIG. It is a schematic block diagram shown.

  The camera of the first embodiment includes a photographic lens 11, a first imaging element 12 as a first imaging unit, a first reflecting mirror 13 as an optical path branching unit, a finder optical system 20, and a primary imaging plane. A screen mat 21 as a second imaging device 14, a second imaging device 14 as a second imaging means, a re-imaging optical system 30, and a subject image captured through the first imaging device 12 or the second imaging device. The subject image display means (not shown) is included.

  The first image sensor 12 is composed of a solid-state image sensor such as a CCD or a CMOS, and has a function of capturing a subject image from a subject light beam that has passed through the photographing lens 11.

  The first reflection mirror 13 is disposed between the photographic lens 11 and the first image pickup device 12, and is configured as a movable mirror that can rotate around an axis 13a. The first reflecting mirror 13 retracts from the optical path from the photographic lens 11 to the first image sensor 12 when the light beam from the photographic lens 11 is guided to the first image sensor 12, while the finder optical system 20 or the reconnection When the light beam is guided to the image optical system 30, it is inserted on the optical path from the taking lens 11 to the first image sensor 12, and has a function as an optical path switching means. When the first reflecting mirror 13 is inserted on the optical path to guide the light beam to the finder optical system 20 or the re-imaging optical system 30, the incident light beam is at an angle of approximately 90 ° with respect to the optical axis of the photographing lens 11. Reflect on.

  The finder optical system 20 is disposed on an optical path in a direction different from that of the first imaging element 12 formed by being reflected by the first reflection mirror 13, and includes a screen mat 21, a second reflection mirror 22, and the like. The third reflecting mirror 23, the fourth reflecting mirror 24, and the eyepiece lens system 25 are included.

  The screen mat 21 is disposed at a position where a subject image is formed from the subject light beam reflected through the first reflecting mirror 13. Further, the screen mat 21 guides light in the visible wavelength region of the transmitted light to the optical paths of the finder optical system 20 and the re-imaging optical system 30, and transmits light of other predetermined wavelengths (for example, infrared light), Separately from these optical paths, a diffractive surface that can be guided to an optical path of a photometric means described later is provided.

  The second reflection mirror 22 is a half mirror. The second reflection mirror 22 is disposed on the reflection optical axis of the first reflection mirror 13 when the first reflection mirror 13 is inserted on the optical path from the photographing lens 11 to the first image sensor 12. The second reflection mirror 22 reflects the light beam reflected through the first reflection mirror 13 at an angle of approximately 90 ° with respect to the reflection optical axis of the first reflection mirror 13.

  The third reflection mirror 23 is disposed on the reflection optical axis of the second reflection mirror 22. Then, the third reflection mirror 23 reflects at an angle of about 90 ° with respect to the reflection optical axis of the second reflection mirror 22.

  The fourth reflection mirror 24 is a half mirror. The fourth reflection mirror 24 is disposed on the reflection optical axis of the third reflection mirror 23. The fourth reflection mirror 24 reflects a part of the incident light beam at an angle of approximately 90 ° with respect to the reflection optical axis of the third reflection mirror 23 and transmits the other incident light beam.

  The second image sensor 14 is arranged on an optical path that deviates from the optical path of the finder optical system 20 when an incident light beam passes through the fourth reflection mirror 24 in the middle of the optical path of the finder optical system 20. And it is comprised so that the to-be-photographed image formed on the screen mat 21 may be imaged.

  The re-imaging optical system 30 includes a second mirror 22, a third mirror 23, a fourth mirror 24, an imaging lens system 31, and a mirror 32. The imaging lens system 31 and the mirror 32 are arranged on an optical path that deviates from the optical path of the finder optical system 20 when the light beam passes through the fourth mirror 24. Then, the re-imaging optical system 30 projects the subject image formed on the screen mat 21 onto the second image sensor 14.

  The subject image display means (not shown) is composed of a liquid crystal monitor, and is arranged below the eyepiece lens system 25 and behind the first image sensor 12. Then, by displaying the subject image picked up by the second image sensor 14, the position of the subject image before photographing in the frame can be monitored. Further, by displaying the subject image picked up by the first image pickup device 12, it is possible to check the recorded image after shooting. These displays can be switched using known switching control means not shown.

Further, the camera of the present embodiment satisfies the following conditional expression (1) in such a configuration.
｜ TAN ⁻¹ (OBJH / ENP1) −TAN ⁻¹ (OBJH / ENP2) | ≦ 20 °
… (1)
However, ENP1 is the distance on the optical axis from the entrance pupil of the re-imaging optical system 30 to the subject image formed on the screen mat 21 (primary imaging plane), and ENP2 is the entrance pupil of the finder optical system 20 to the screen. This is the distance on the optical axis to the subject image formed on the mat 21 (primary imaging plane). The eyepoint of the finder optical system 20 here is an arbitrary value within a range of 0 to 50 mm from the final surface of the finder optical system 20 toward the observation side. OBJH is the maximum effective ray height on the screen mat 21 (primary imaging plane).

Furthermore, the camera of the present embodiment preferably has the following configuration.
The re-imaging optical system 30 has at least one positive lens and one negative lens, and satisfies the following conditional expression (2).
10 ≦ νp − νn (2)
Where νp is the Abbe number of the positive lens among the lenses constituting the re-imaging optical system 30 and νn is the Abbe number of the negative lens among the lenses constituting the re-imaging optical system 30. Is a number.

The re-imaging optical system 30 has at least two positive lenses and satisfies the following conditional expression (3).
50 ≤ vpmx (3)
However, νpmx is the Abbe number of the positive lens having the highest power among the lenses constituting the re-imaging optical system 30 at the d-line.

The re-imaging optical system 30 includes at least one plastic lens.
The re-imaging optical system 30 includes at least one aspheric lens.
Further, a solid-state image sensor that is smaller in size than the first image sensor 12 is used for the second image sensor 14.

  Further, the camera according to the present embodiment includes photographing information display means 41 and in-focus position display means 42 as common optical means constituting the finder optical system 20 and the re-imaging optical system 30.

  The shooting information display means 41 has a function of displaying information related to shooting, such as shutter speed, Fno, and the remaining number of shots, on the edge or outside of the subject image.

  The in-focus location display means 42 is configured to include a light source such as an LED, for example, and among a plurality of in-focus setting points (multi-point distance measurement), a position to focus on, a position in focus, etc. A function of displaying a predetermined mark indicating a position related to focusing on the subject image is provided.

  In the camera of the present embodiment, the photographing information display unit 41 and the in-focus location display unit 42 are arranged on the opposite side of the screen mat 21 with the second reflection mirror 22 interposed therebetween. In addition, the direction of the optical axis of the emitted light is adjusted so as to be along the reflected optical axis of the second reflecting mirror 22. The light emitted from the photographing information display unit 41 and the in-focus location display unit 42 is superimposed on a predetermined location of the subject image reflected through the second reflection mirror 22.

Further, the camera of the present embodiment includes a photometric lens 51 and a photometric image sensor 52 as photometric means.
The photometric lens 51 is arranged in the vicinity of the imaging lens system 31 and at a position slightly shifted from the incident optical axis to the imaging lens system 31 toward the photographing lens 11 side. The side light imaging element 52 is configured by a solid-state imaging element such as a CCD, and receives light that has passed through the photometric lens 51.

In the camera of the present embodiment configured as described above, when the subject is observed, the first reflecting mirror 13 guides the light beam to the finder optical system 20 or the re-imaging optical system 30 as shown in FIG. It is inserted on the road and rotates at an angle of about 90 ° with respect to the optical axis of the taking lens 11 to reflect the incident light beam. The light beam from the subject reflected through the first reflecting mirror 13 forms an image on the screen mat 21, is then reflected by the second reflecting mirror 22 and the third reflecting mirror 23, and enters the fourth reflecting mirror 24. To do. A part of the light beam from the subject incident on the fourth reflecting mirror 24 is reflected by the fourth reflecting mirror 24, enters the eyepiece lens system 25, and forms an image on the observer's eye via the eyepiece lens system 25. . On the other hand, the light beam from the subject that has passed through the fourth reflecting mirror 24 forms an image on the imaging surface of the second imaging element 14 through the imaging lens system 31 and the mirror 32 and is imaged.
The captured subject image is displayed on a liquid crystal monitor (not shown).

  Note that light having a predetermined wavelength (for example, infrared light) out of the light transmitted through the screen mat 21 is diffracted by a predetermined amount from the optical axes of the finder optical system 20 and the re-imaging optical system 30. Then, the light is reflected by the second reflection mirror 22 and the third reflection mirror 23. Then, the light transmitted through the fourth reflection mirror 24 is received by the photometric image sensor 52 through the photometric lens 51. The light quantity information received by the photometric image sensor 52 is transmitted to a well-known calculation control means (not shown). The arithmetic control unit controls the shutter speed and the diaphragm and the like based on the light amount information.

Further, at the time of subject observation, the photographing information display unit 41 emits light having information related to photographing such as shutter speed, Fno, and the remaining number of images that can be photographed so as to overlap the end of the subject image and the outside. In addition, the in-focus location display means 42 is a predetermined mark indicating a position related to in-focus, such as a position to focus on or a position in focus, among a plurality of in-focus setting points (multi-point distance measurement). Is emitted as light so as to overlap the subject image.
The light emitted from the photographing information display means 41 and the in-focus position display means 42 passes through the second reflecting mirror 22 and is superimposed on the light flux from the subject.

  On the other hand, at the time of photographing, as shown in FIG. 2, the first reflecting mirror 13 is retracted from the optical path from the photographing lens 11 to the first image sensor 12. As a result, the light flux from the subject passing through the photographing lens 11 is imaged through the first image sensor.

  At this time, according to the camera of the present embodiment, since the conditional expression (1) is satisfied, the entrance pupil position of the finder optical system 20 and the entrance pupil position of the re-imaging optical system 30 projected onto the second image sensor 14 are satisfied. In the subject image observed through the finder optical system 20 or the subject image picked up through the second image sensor 14, vignetting of light or a significant amount of peripheral light It is possible to suppress the occurrence of a decrease, and it is possible to suppress the occurrence of practical problems such as hindering observation using an optical viewfinder or a liquid crystal viewfinder.

  Further, according to the camera of the present embodiment, in the configuration in which the re-imaging optical system 30 has at least one positive and negative lens, the following conditional expression (2) is satisfied, An increase in chromatic aberration due to a reduction in the achromatic effect by the negative lens can be suppressed, and a necessary and sufficient resolving power corresponding to the pixel pitch of the monitor display imaging device can be obtained.

  Further, according to the camera of the present embodiment, in the configuration in which the re-imaging optical system 30 includes at least two positive lenses, the positive lens having the highest power can be obtained by satisfying the following conditional expression (3). An increase in chromatic aberration due to an increase in the dispersion due to can be suppressed, and a necessary and sufficient resolving power corresponding to the pixel pitch of the monitor display image sensor can be obtained.

  Further, according to the camera of the present embodiment, the re-imaging optical system 30 includes at least one or more plastic lenses, so that it is cheap and necessary and sufficient performance compared to the case of using a glass lens. Can be secured.

  In addition, according to the camera of the present embodiment, the re-imaging optical system includes at least one aspherical lens, so that necessary and sufficient performance can be ensured with a small number of lenses. This makes it possible to reduce the size and cost of the camera housing.

  Moreover, according to the camera of this embodiment, compared with the 1st image pick-up element 12 used for a 1st image pickup means, the direction of the 2nd image pick-up element 14 used for a 2nd image pick-up means can be made small, The light flux can be reduced, and the size of the camera can be reduced. In addition, the use of a small image sensor can reduce power consumption, which is advantageous for increasing the number of images that can be taken as much as possible. Further, the magnification by the re-imaging optical system 30 is less than 1, and the principal point position of the re-imaging optical system 30 can be arranged on the second imaging means (second imaging element 14) side, which is advantageous in layout. For example, it becomes easy to arrange a lens element on the optical path branched from the optical path of the finder optical system.

  Further, according to the camera of the present embodiment, the photographing information display means 41 and the in-focus position display means 42 are provided as some common optical means constituting the finder optical system 20 and the re-imaging optical system 30. Thus, the object image data formed on the primary image plane (screen mat 21) is confirmed via the finder optical system 20 and the re-imaging optical system 30, and at the same time, the optical information is obtained via the photographing information display means 41. The in-focus location can be confirmed via the in-focus location display means 42.

  Further, according to the camera of the present embodiment, the primary imaging surface is the screen mat 12, the mat surface is arranged in parallel to the primary imaging surface, and the conditional expression (1 ′) is satisfied, Deterioration due to the diffusion of the subject image is minimized, and the subject luminous flux is incident on the entrance pupils of the finder optical system 20 and the re-imaging optical system 30 due to the diffusion of the mat surface, and passes through the finder and the second imaging means. Thus, it is possible to prevent vignetting of the light and a remarkable decrease in the amount of peripheral light from the periphery of the image captured. Further, by satisfying the conditional expression (1 ′), the difference between the entrance pupil positions of the finder optical system 20 and the respective optical systems as the second imaging means is reduced, and the refraction and matting of the surface having the light collecting action are reduced. Even if the subject luminous flux is affected by the diffusion of the surface, it is possible to make it difficult to cause vignetting of the light and a remarkable decrease in the amount of peripheral light at the periphery of the screen of the image picked up through the viewfinder and the second image pickup means.

(Second Embodiment)
FIG. 3 is a schematic configuration diagram showing an arrangement relationship of optical members in the camera according to the second embodiment of the present invention.

In the camera of the second embodiment, instead of the first reflection mirror 13, a first reflection mirror 13 ′ composed of a half mirror is fixed on the optical path between the photographing lens 11 and the first image sensor 12. Yes.
The first reflecting mirror 13 ′ transmits a part of the incident light beam from the photographing lens 11 and guides it to the first image sensor 12, and at the same time, directs the other incident light beam to approximately 90 ° with respect to the optical axis of the photographing lens 11. Is arranged so as to guide the light beam to the finder optical system 20 or the re-imaging optical system 30, and has a function as an optical path dividing means.

In the camera of the present embodiment, the photographing information display means 41 and the in-focus location display means 42 are arranged in parallel to the surface of the screen mat 21.
The in-focus location display means 42 is constituted by a parallel plate-like display plate (for example, a transmissive screen such as a transmissive LCD), and is disposed to face the screen mat 21.

Furthermore, in the camera of the present embodiment, the photometric lens 51 is disposed in the vicinity of the imaging lens 31 and slightly shifted from the incident optical axis to the imaging lens 31 toward the eyepiece lens system 25 side.
Further, the screen mat 21 guides light in the visible wavelength region of the transmitted light to the optical paths of the finder optical system 20 and the re-imaging optical system 30, and transmits light of other predetermined wavelengths (for example, infrared light), In order to be able to guide to the optical path of the photometry means separately from these optical paths, a diffraction surface having a diffraction angle different from that of the first embodiment is provided.
Of the light transmitted through the screen mat 21, light having a predetermined wavelength (for example, infrared light) is diffracted by a predetermined amount from the optical axes of the finder optical system 20 and the re-imaging optical system 30 and is diffracted. The photometric image sensor 52 receives light through the third reflecting mirror 23 and the photometric lens 51.

In addition, the second imaging element 14 is disposed to face the imaging lens 31 and does not include the mirror 32 in the camera of the first embodiment.
Other configurations and operational effects are substantially the same as those of the camera of the first embodiment.

(Third embodiment)
FIG. 4 is a schematic configuration diagram showing an arrangement relationship of optical members when an object is observed with an optical viewfinder in a camera according to a third embodiment of the present invention, and FIG. 5 is imaged by a second image sensor in the camera of FIG. It is a schematic block diagram which shows the arrangement | positioning relationship of an optical member when observing a to-be-photographed image.

In the camera of the third embodiment, a fourth reflection mirror 24 ′ is provided as a second optical path branching unit instead of the fourth reflection mirror 24 in the camera of the second embodiment shown in FIG.
The fourth reflection mirror 24 ′ is configured as a movable mirror that can rotate around the axis 24a ′. The fourth reflection mirror 24 ′ is inserted on the optical path from the third reflection mirror 23 to the second image sensor 14 as shown in FIG. When the light beam from the photographic lens 11 is guided to the image sensor 14, as shown in FIG. 5, it is retracted from the optical path from the third reflecting mirror 23 to the second image sensor 14, and functions as an optical path switching unit. It has.
Other configurations and operational effects are almost the same as those of the camera of the second embodiment.

In the cameras of the first to third embodiments, the screen mat 21 serving as the primary imaging surface disposed on the optical path to the second image sensor 14 may have a diffusion function. For example, it may have a transmission function made of a through plate having little or no diffusibility.
Further, if necessary, a surface (for example, a Fresnel lens surface) having a condensing function may be provided in the vicinity of the primary imaging surface (on the opposite side of the screen mat 21 from the primary imaging surface).
In the camera of the third embodiment, when the third reflecting mirror 23 is inserted in the optical path reaching the second image sensor 14, the display operation of the photographing information display means 41 and the in-focus position display means 42 is turned off. It is also possible to provide a known control means (not shown) that controls so as to be.

Next, embodiments of the present invention will be described with reference to the drawings.
6 is a cross-sectional view along the optical axis showing the optical configuration of the re-imaging optical system 30 in the camera according to Embodiment 1 of the present invention, and FIG. 7 shows various aberrations of the re-imaging optical system 30 shown in FIG. FIG. In FIG. 6, for the sake of convenience, the optical configuration is shown by converting the optical axis into a straight line. Further, the mirror is omitted, and the configuration of the imaging lens system 31 is substantially shown. Spherical aberration and lateral chromatic aberration are numerical values at respective wavelengths of 587.6 nm (d line: solid line), 486.1 nm (F line: dotted line), and 656.3 nm (C line: one-dot chain line).

The camera according to the present embodiment employs any one of the first to third embodiments as a basic optical member arrangement.
In addition, in the camera of the present embodiment, the imaging lens system 31 in the re-imaging optical system 30 is a cemented lens of a biconvex lens L31 ₁ and a negative meniscus lens L31 ₂ having a concave surface facing the object side in order from the object side. And a stop S, a negative meniscus lens L31 ₃ having a convex surface facing the object side, and a positive meniscus lens L31 ₄ having a convex surface facing the object side. In FIG. 6, FL is a filter such as an infrared cut filter or an ultraviolet cut filter, CG is a cover glass, and IM is an image pickup surface of the second image sensor 14.
The negative meniscus lens L31 ₃ and the positive meniscus lens L31 ₄ are each composed of a plastic lens.
In addition, in the camera of this embodiment, the first image sensor 12 has a size of 4/3 type and the second image sensor 14 has a size of 1/4 type.

Next, numerical data of optical members constituting the re-imaging optical system 30 in the camera of this embodiment shown in FIG. 6 will be shown.
In the numerical data, f is a focal length, Fno is an F number, S ₀ , S ₁ , S ₂ ,... Are surface numbers, r ₀ , r ₁ , r ₂ ,. , D ₀ , d ₁ , d ₂ ,... Are the surface spacing (thickness or air spacing) of the optical member, and n _d0 , n _d1 , n _d2 ,. The refractive index at 6 nm), ν _d0 , ν _d1 , ν _d2 ,... Is the Abbe number at the d-line of the optical member, and d ₀ is the light from the primary imaging surface to the first surface of the imaging lens system 31. The distance on the axis. These are common in the numerical data of the following embodiments.
In addition, in the specification table of the numerical data, the surface given (aspherical surface) is an aspherical surface. The expression representing the aspherical shape is as follows: the height perpendicular to the optical axis is H, the amount of displacement in the optical axis direction at the height H when the top is the origin is X (H), the paraxial radius of curvature is R, the cone When the coefficient is K, the second order, the fourth order, the sixth order, the eighth order, and the tenth order aspherical coefficients are A, B, C, D, and E, respectively, it is expressed by the following equation (4).
X (H) = (H ² / R) / {1+ [1− (1 + K) · (H ² / R ² )] ^1/2 }
+ AH ² + BH ⁴ + CH ⁶ + DH ⁸ + EH ¹⁰ (4)

Numerical data 1 (Example 1) Optical system of second imaging means (for framing monitor) (re-imaging optical system 30)
f = 10.58mm
Fno = 2.77
S ₀ r ₀ = ∞ (primary imaging plane) d ₀ = 67.00
S ₁ r ₁ = 7.801 d ₁ = 3.18 n _d1 = 1.51633 ν _d1 = 64.14
S ₂ r ₂ = −3.320 d ₂ = 0.70 n _d2 = 1.54814 ν _d2 = 45.79
S ₃ r ₃ = −28.993 d ₃ = 0.03
S ₄ r ₄ = ∞ (aperture) d ₄ = 5.47
S ₅ r ₅ = 3.4874 d ₅ = 1.00 n _d5 = 1.58423 ν _d5 = 30.49
S ₆ r ₆ = 2.3412 (aspherical surface) d ₆ = 1.16
S ₇ r ₇ = 2.8290 (aspherical surface) d ₇ = 1.68 n _d7 = 1.52542 ν _d7 = 55.78
S ₈ r ₈ = 4.6362 d ₈ = 1.78
S ₉ r ₉ = ∞ d ₉ = 0.75 n _d9 = 1.51633 ν _d9 = 64.14
S ₁₀ r ₁₀ = ∞ d ₁₀ = 0.50
S ₁₁ r ₁₁ = ∞ d ₁₁ = 0.50 n _d11 = 1.51633 ν _d11 = 64.14
S ₁₂ r ₁₂ = ∞ d ₁₂ = 0.37
S ₁₃ r ₁₃ = ∞ (image plane)
Aspherical surface 6th surface (S ₆ )
R = 2.3412 K = -0.5159
A = 0.0000 x 10 ⁰ B = -4.0713 x 10 ^-4 C = 1.3256 x 10 ^-3 D = -4.2298 x 10 ^-4
E = 7.4181 × 10 ^-5
Surface No. ₇ (S 7)
R = 2.8290 K = -0.7874
A = 0.0000 × 10 ⁰ B = -8.2674 × 10 ^-4 C = 4.5775 × 10 ^-4 D = -4.6031 × 10 ^-5
E = 4.3502 × 10 ^-6

  FIG. 8 is a cross-sectional view along the optical axis showing the optical configuration of the re-imaging optical system 30 in the camera according to the second embodiment of the present invention, and FIG. 9 shows various aberrations of the re-imaging optical system 30 shown in FIG. FIG. In FIG. 8, for the sake of convenience, the optical configuration is shown by converting the optical axis into a straight line. Further, the mirror is omitted, and the configuration of the imaging lens system 31 is substantially shown. Spherical aberration and lateral chromatic aberration are numerical values at respective wavelengths of 587.6 nm (d line: solid line), 486.1 nm (F line: dotted line), and 656.3 nm (C line: one-dot chain line).

The camera of the present embodiment also employs any one of the configurations of the first to third embodiments with respect to the basic arrangement of the optical members.
In addition, in the camera of the present embodiment, the imaging lens system 31 in the re-imaging optical system 30 includes, in order from the object side, a positive meniscus lens L31 ₁ ′ having a convex surface facing the object side, a diaphragm S, and a biconcave lens. L31 ₂ ′ and a biconvex lens L31 ₃ ′. In FIG. 8, FL is a filter such as an infrared cut filter or an ultraviolet cut filter, CG is a cover glass, and IM is an imaging surface of the second image sensor 14.
In addition, in the camera of this embodiment, the first image sensor 12 has a size of 4/3 type and the second image sensor 14 has a size of 1/4 type.

Next, numerical data of optical members constituting the re-imaging optical system 30 of this embodiment shown in FIG. 8 will be shown.
Numerical data 2 (Example 2) Optical system of second imaging means (for framing monitor) (re-imaging optical system 30)
f = 10.42 mm
Fno = 2.85
S ₀ r ₀ = ∞ (primary imaging plane) d ₀ = 63.00
S ₁ r ₁ = 6.1409 d ₁ = 2.00 n _d1 = 1.72916 ν _d1 = 54.68
S ₂ r ₂ = 139.8827 (aperture) d ₂ = 0.54
S ₃ r ₃ = -17.8971 d ₃ = 1.80 n _d3 = 1.59270 ν _d3 = 35.31
S ₄ r ₄ = 4.2153 d ₄ = 0.50
S ₅ r ₅ = 6.9968 d ₅ = 5.88 n _d5 = 1.72916 ν _d5 = 54.68
S ₆ r ₆ = -10.8500 d ₆ = 5.00
S ₇ r ₇ = ∞ d ₇ = 0.75 n _d7 = 1.51633 ν _d7 = 64.14
S ₈ r ₈ = ∞ d ₈ = 0.50
S ₉ r ₉ = ∞ d ₉ = 0.50 n _d9 = 1.51633 ν _d9 = 64.14
S ₁₀ r ₁₀ = ∞ d ₁₀ = 0.74
S ₁₁ r ₁₁ = ∞ (image plane)

  FIG. 10 is a cross-sectional view along the optical axis showing the optical configuration of the re-imaging optical system 30 in the camera according to Example 3 of the present invention, and FIG. 11 shows various aberrations of the re-imaging optical system 30 shown in FIG. FIG. In FIG. 10, for the sake of convenience, the optical configuration is shown by converting the optical axis into a straight line. Further, the mirror is omitted, and the configuration of the imaging lens system 31 is substantially shown. Spherical aberration and lateral chromatic aberration are numerical values at respective wavelengths of 587.6 nm (d line: solid line), 486.1 nm (F line: dotted line), and 656.3 nm (C line: one-dot chain line).

The camera of the present embodiment also employs any one of the configurations of the first to third embodiments with respect to the basic arrangement of the optical members.
In addition, in the camera of the present embodiment, the imaging lens system 31 in the re-imaging optical system 30 includes, in order from the object side, an aperture S, a positive meniscus lens L31 ₁ ″ having a convex surface facing the object side, and an object side. And a positive meniscus lens L31 ₂ ″ having a convex surface. In FIG. 10, FL is a filter such as an infrared cut filter or an ultraviolet cut filter, CG is a cover glass, and IM is an image pickup surface of the second image sensor 14.
The positive meniscus lens L31 ₁ ″ and the positive meniscus lens L31 ₂ ″ are each formed of a plastic lens.
In addition, in the camera of this embodiment, the first image sensor 12 has a size of 4/3 type and the second image sensor 14 has a size of 1/4 type.

Next, numerical data of optical members constituting the re-imaging optical system 30 of the present embodiment shown in FIG. 10 will be shown.
Numerical data 3 (Example 3) Optical system of second image pickup means (for framing monitor) (re-imaging optical system 30)
f = 9.96mm
Fno = 2.80
S ₀ r ₀ = ∞ (primary imaging plane) d ₀ = 64.00
S ₁ r ₁ = ∞ (aperture) d ₁ = 0.50
S ₂ r ₂ = 4.082 (aspherical surface) d ₂ = 6.00 n _d2 = 1.52542 ν _d2 = 55.78
S ₃ r ₃ = 2.927 d ₃ = 1.00
S ₄ r ₄ = 3.137 (aspherical surface) d ₄ = 1.20 n _d4 = 1.52542 ν _d4 = 55.78
S ₅ r ₅ = 12.169 (aspherical surface) d ₅ = 3.40
S ₆ r ₆ = ∞ d ₆ = 0.75 n _d6 = 1.51633 ν _d6 = 64.14
S ₇ r ₇ = ∞ d ₇ = 0.50
S ₈ r ₈ = ∞ d ₈ = 0.50 n _d8 = 1.51633 ν _d8 = 64.14
S ₉ r ₉ = ∞ d ₉ = 0.71
S ₁₀ r ₁₀ = ∞ (image plane)
Aspherical coefficient second surface (S ₂ )
R = 4.0815 K = -0.3784
The fourth surface (S ₄₎
R = 3.1372 K = -0.7595
Fifth side (S ₅ )
R = 12.169 K = 8.7922

  FIG. 12 is a cross-sectional view along the optical axis showing the optical configuration of the finder optical system 20 in the camera according to Embodiment 4 of the present invention, and shows a state when the diopter is −1 diopter. In FIG. 12, for the sake of convenience, the optical configuration is shown by converting the optical axis into a straight line. Further, the mirror is omitted, and the configuration of the eyepiece lens system 25 is substantially shown.

The camera of the present embodiment also employs any one of the configurations of the first to third embodiments with respect to the basic arrangement of the optical members.
In the camera of the present embodiment, the re-imaging optical system 30 employs any of the configurations of the first to third embodiments.
On top of that, in the camera of this embodiment, the eyepiece system 25 of the finder optical system 20 includes, in order from the object side, a convex positive meniscus lens L25 ₁ with its object side, a biconvex lens L25 _2, biconcave lens L25 It consists of _three . In FIG. 12, FC is a parallel plate that functions as a filter and a cover glass such as an infrared cut filter and an ultraviolet cut filter, and EP is an exit pupil position.
The positive meniscus lens L25 ₁ and the biconcave lens L25 ₂ are configured to be movable by a predetermined amount on the optical axis for diopter adjustment.

Next, numerical data of optical members constituting the finder optical system 20 of the present embodiment shown in FIG. 12 will be shown. The diopter adjustment range is +1.5 diopter to -3.5 diopter.
Numerical data 4 (Example 4) Optical system for optical viewfinder (finder optical system 20)
f = 3608.54 (+ 1.5dpt) ~ 415.32 (-1dpt) ~ 202.12 (-3.5dpt) mm
Fno = 3.91-3.94-3.95
S ₀ r ₀ = ∞ (primary imaging plane) d ₀ = 80.35
S ₁ 'r ₁ ' = 19.333 d ₁ = 7.10 n _d1 = 1.51633 ν _d1 = 64.14
S ₂ 'r ₂ ' = 71.354 d ₂ = (variable)
S ₃ 'r ₃ ' = 18.149 (aspherical surface) d ₃ = 5.61 n _d3 = 1.52542 ν _d2 = 55.78
S ₄ 'r ₄ ' = -264.728 d ₄ = (variable)
S ₅ 'r ₅ ' = -88.178 d ₅ = 1.80 n _d5 = 1.58423 ν _d5 = 30.49
S ₆ 'r ₆ ' = 12.438 d ₆ = 4.41
S ₇ 'r ₇ ' = ∞ d ₇ = 1.20 n _d7 = 1.51633 ν _d7 = 64.14
S ₈ 'r ₈ ' = ∞ d ₈ = 16.67
S ₉ 'r ₉ ' = ∞ (observer's pupil)
Aspherical coefficient third surface (S ₃ ')
R = 18.1494 K = 0.000
A = 0.0000 × 10 ⁰ B = -2.1895 × 10 ^-5 C = -6.7082 × 10 ^-8
D = -4.9542 × 10 ^-10 E = 0.000 × 10 ⁰

ただし、アイポイントは、ファインダ光学系２０の最終面から２２．３ｍｍとしたときの値である。 Next, conditional parameters in the camera of each embodiment of the present invention are shown in Tables 1 to 5 below.

However, the eye point is a value when the distance from the final surface of the finder optical system 20 is 22.3 mm.

It is a schematic block diagram which shows the arrangement | positioning relationship of the optical member at the time of the object observation before imaging | photography with the camera concerning 1st Embodiment of this invention. It is a schematic block diagram which shows the arrangement | positioning relationship of the optical member at the time of object photography with the camera of FIG. It is a schematic block diagram which shows the arrangement | positioning relationship of the optical member in the camera concerning 2nd Embodiment of this invention. It is a schematic block diagram which shows the arrangement | positioning relationship of an optical member when observing a to-be-photographed object with the optical finder in the camera concerning 3rd Embodiment of this invention. FIG. 5 is a schematic configuration diagram illustrating an arrangement relationship of optical members when a subject image captured by a second image sensor in the camera of FIG. 4 is observed on a monitor. It is sectional drawing which follows the optical axis which shows the optical structure of the re-imaging optical system 30 in the camera concerning Example 1 of this invention. FIG. 7 is a diagram illustrating various aberrations of the re-imaging optical system 30 illustrated in FIG. 6. It is sectional drawing which follows the optical axis which shows the optical structure of the re-imaging optical system 30 in the camera concerning Example 2 of this invention. FIG. 9 is a diagram illustrating various aberrations of the re-imaging optical system 30 illustrated in FIG. 8. It is sectional drawing which follows the optical axis which shows the optical structure of the re-imaging optical system 30 in the camera concerning Example 3 of this invention. FIG. 11 is a diagram illustrating various aberrations of the re-imaging optical system 30 illustrated in FIG. 10. It is sectional drawing which follows the optical axis which shows the optical structure of the finder optical system 20 in the camera concerning Example 4 of this invention, and has shown the state when a diopter is -1 diopter (diopter).

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Shooting lens 12 1st image pick-up element 13, 13 '1st reflective mirror 13a Axis 14 2nd image pick-up element 20 Finder optical system 21 Screen mat (primary image formation surface)
22 Second Reflecting Mirror 23 Third Reflecting Mirror 24, 24 ′ Fourth Reflecting Mirror 24a ′ Axis 25 Eyepiece Lens System 30 Re-imaging Optical System 31 Imaging Lens System 32 Mirror 41 Imaging Information Display Means 42 Focusing Location Display Means 51 Photometry Lens 52 Photometric image sensor L25 ₁ Positive meniscus lens with convex surface facing object side L25 ₂ Biconvex lens L25 ₃ Biconcave lens L31 ₁ Biconvex lens L31 ₁ 'Positive meniscus lens with convex surface facing object side L31 ₁ ”Convex surface on object side Positive meniscus lens L31 ₂ negative meniscus lens with concave surface facing the object side L31 ₂ 'biconcave lens L31 ₂ ”positive meniscus lens with convex surface facing the object side L31 ₃ negative meniscus lens with convex surface facing the object side L31 ₃ 'positive meniscus lens FL filter FC filter having a convex surface directed toward the biconvex lens L31 ₄ object side Imaging surface S diaphragm EP exit pupil position of the parallel plate CG cover glass IM second image sensor 14 which functions as a fine cover glass

Claims (8)

First imaging means for imaging a subject image from a subject luminous flux that has passed through the photographing lens;
On the optical path between the photographic lens and the first imaging means, it is possible to guide the subject light flux to an optical path toward the first imaging means and an optical path in a direction different from the first imaging means. Configured optical path branching means;
A finder optical system disposed on an optical path in a direction different from that of the first imaging means;
An optical surface provided in a part of the optical elements constituting the finder optical system, wherein a subject image from the subject light beam reflected through the optical path branching unit is formed;
Second for imaging the in the middle of the finder optical system optical path be located on an optical path which is branched in a direction out of the optical path of the finder optical science-based, object image formed on the primary image forming surface Imaging means,
A re-imaging optical system that projects a subject image formed on the primary imaging plane onto the second imaging means;
With comprises an object image display means capable of displaying a subject image captured through the first or second imaging means,
As a part of the common optical means constituting the finder optical system and the re-imaging optical system, a photographing information display means and an in-focus location display means are provided,
A camera that satisfies the following conditional expression (1):
｜ TAN ⁻¹ (OBJH / ENP1) −TAN ⁻¹ (OBJH / ENP2) | ≦ 20 °
… (1)
However, ENP1 is the distance on the optical axis from the entrance pupil of the re-imaging optical system to the subject image formed on the primary imaging plane, and ENP2 is the primary image from the entrance pupil of the finder optical system. This is the distance on the optical axis to the subject image formed on the surface. The eyepoint of the finder optical system here is an arbitrary value within a range of 0 to 50 mm from the final surface of the finder optical system toward the observation side. OBJH is the maximum effective ray height on the primary imaging plane. The camera according to claim 1, wherein the re-imaging optical system includes at least one positive lens and one negative lens, and satisfies the following conditional expression (2).
10 ≦ νp − νn (2)
Where νp is the Abbe number of the positive lens among the lenses constituting the re-imaging optical system, and νn is the Abbe number of the negative lens among the lenses constituting the re-imaging optical system. Is a number. The camera according to claim 1 or 2, wherein the re-imaging optical system has at least two positive lenses and satisfies the following conditional expression (3).
50 ≤ vpmx (3)
However, νpmx is the Abbe number of the positive lens having the highest power among the lenses constituting the re-imaging optical system at the d-line.   The camera according to claim 1, wherein the re-imaging optical system includes at least one plastic lens.   The camera according to claim 1, wherein the re-imaging optical system includes at least one aspheric lens.   The camera according to claim 1, wherein an image sensor used for the second image pickup unit is smaller than an image sensor used for the first image pickup unit. In the vicinity of the primary imaging plane, at least one of a condensing surface and a matte surface is disposed in parallel with the primary imaging plane, and satisfies the following conditional expression (1 ′). The camera according to any one of claims 1 to 6 .
｜ TAN ⁻¹ (OBJH / ENP1) −TAN ⁻¹ (OBJH / ENP2) | ≦ 15 °
… (1 ')
However, ENP1 is the distance on the optical axis from the entrance pupil of the re-imaging optical system to the subject image formed on the primary imaging plane, and ENP2 is the primary image from the entrance pupil of the finder optical system. This is the distance on the optical axis to the subject image formed on the surface. The eyepoint of the finder optical system here is an arbitrary value within a range of 0 to 50 mm from the final surface of the finder optical system toward the observation side. OBJH is the maximum effective ray height on the primary imaging plane. The finder optical system and the re-imaging optical system comprises a plurality of optical reflection surfaces, one of said plurality of optical reflecting surfaces, according to claim 1-7, characterized in that a light-transmitting properties The camera according to any one of the above.

Images