JPH11231411A - Camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make accurately assessable a first video without viewing the first video by accurately recording or displaying a secondary image and assessing a second video which is the secondary image of the first video. SOLUTION: This camera is provided with a silver salt film 12 where a primary image formed by a photographing lens 1 is exposed and a solid-state image pickup element where the secondary image obtained by the image reformation of the primary image formed by the photographing lens 1 by an image reformation lens 9 is exposed and is provided with a data correcting part 15 correcting the difference of a video between the primary image and the secondary image for the video exposed on the solid-state image pickup element 10 based on a lens data 16 and a stop value 17 or the like, a memory 19 recording a correction data from the data correcting part 15 and a display part 21 displaying the correction data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera for recording or displaying an image exposed on an exposure unit, and more particularly, a camera for exposing a secondary image formed on the exposure unit by a re-imaging optical system. It is about.

[0002]

2. Description of the Related Art The device disclosed in Japanese Patent Application Laid-Open No. 58-106530 is
A single-lens reflex camera which can be used as a silver halide camera or as an electronic camera by itself is shown in FIG.
When this device is used as a silver halide camera, the light flux from the photographing lens 51 jumps up the quick return mirror 52 and guides it to the film surface 53 during photographing. When used as an electronic camera, the light flux from the photographing lens 51 is reflected by the quick return mirror 52 to form an image on the solid-state imaging device 54, and the image processed by the signal processing circuit 59 is displayed on the display 55, and the image is displayed on the display 55. The observation is made through the pentaprism 57 and the eyepiece 58. When used as a silver halide camera, the solid-state imaging device 54 and the display 55 are switched to a focusing screen 56 to observe a subject.

The apparatus disclosed in Japanese Patent Application Laid-Open No. Sho 62-159577 includes a photographing lens 61, a quick return mirror 62, a silver halide film 63, a focusing screen 64, a mirror 65, a lens 66, and an image sensor 67, as shown in FIG. It has. Then, the quick return mirror 62 is flipped up to expose the silver halide film 63 and the quick return mirror 6 is exposed.
When the number 2 is lowered, the reticle 64, the mirror 65,
The light flux is guided to the image sensor 67 through the lens 66 to record an electronic image.

The apparatus disclosed in Japanese Patent Application Laid-Open No. Hei 8-223460 is shown in FIG.
As shown in FIG. 6, a silver halide camera 71, an electronic camera 72,
A shutter release button 73 and a monitor device 74 are provided. Then, in response to a signal from the shutter release button 73, the silver halide camera 71 and the electronic camera 72 are simultaneously photographed, and the image of the electronic camera 72 is displayed on the monitor device 74.

[0005]

However, the above three apparatuses can take both silver halide photographs and electrophotographs, respectively. If a silver halide photograph is taken at about the same time and the electronic photograph is used for checking the exposure of the silver halide photograph, a difference occurs between the two images (particularly, the peripheral portion).
There was a problem that the correct exposure cannot be determined.

Accordingly, it is a first object of the present invention to provide a camera capable of accurately recording or displaying a secondary image. The present invention also provides a second image, which is a secondary image of the first video.
A second object is to provide a camera that can accurately evaluate the first video without evaluating the first video by evaluating the first video.

[0007]

In order to achieve the above-mentioned object, a first aspect of the present invention is a secondary image obtained by forming a primary image formed by a photographing optical system further by a re-imaging optical system. Is a camera comprising: an exposure unit to be exposed; a recording unit that records an image exposed to the exposure unit; and a correction unit that corrects a difference in image between the primary image and the secondary image.

According to a second aspect of the present invention, there is provided an exposure unit for exposing a primary image formed by a photographing optical system and a secondary image formed by a re-imaging optical system, And a correction unit configured to correct a difference in video between the primary image and the secondary image.

According to a third aspect of the present invention, there is provided a first exposure section to which a primary image formed by a photographing optical system is exposed, and a primary image formed by the photographing optical system is further formed by a re-imaging optical system. A second exposure unit to which the imaged secondary image is exposed, a recording unit to record an image exposed to the second exposure unit, and a correction to correct a difference between the primary image and the secondary image And a camera provided with a unit.

According to a fourth aspect of the present invention, there is provided a first exposure section to which a primary image formed by a photographing optical system is exposed, and a primary image formed by the photographing optical system is further formed by a re-imaging optical system. A second exposure unit on which the imaged secondary image is exposed, a display unit for displaying an image exposed on the second exposure unit, and a correction for correcting a difference between an image of the primary image and an image of the secondary image And a camera provided with a unit.

[0011] The invention of claim 5 is the invention of claim 3 or claim 4.
5. The camera according to claim 1, wherein a silver halide film is disposed in the first exposure section, and a solid-state imaging device is disposed in the second exposure section.

[0012] The invention of claim 6 is the first to fifth aspects of the present invention.
5. The camera according to claim 1, wherein the correction unit corrects a difference in video between the primary image and the secondary image due to light loss of the re-imaging optical system. Camera.

[0013] The invention of claim 7 is the invention of claims 1 to 6.
5. The camera according to claim 1, wherein the correction unit corrects a total or partial decrease in the amount of light of the secondary image with respect to the primary image due to light loss of the re-imaging optical system. A camera characterized by the following.

According to an eighth aspect of the present invention, in the camera according to any one of the first to third aspects, the recording unit records the secondary image corrected by the correction unit. Camera.

According to a ninth aspect of the present invention, in the camera according to any one of the second, fourth and fifth aspects, the display unit displays the secondary image corrected by the correction unit. Camera.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a diagram showing an optical system of a camera according to a first embodiment of the present invention. The light beam that has passed through the taking lens 1 forms an image on a focusing screen 4 through a stop 2 and a quick return mirror 3, and further, is observed by a photographer through a condenser lens 5, a pentaprism 6, a beam splitter 7, and an eyepiece 8. Is done. Here, the aperture 2 is
Normally, no matter how many apertures are set, the aperture is always open, and a so-called instantaneous aperture method is used in which the aperture is instantaneously reduced to the set value immediately before shooting.

When the silver halide film 12 is exposed, the aperture 2 is stopped down, the quick return mirror 3 is flipped up, and the shutter 11 is opened for a predetermined time. When performing exposure on the solid-state imaging device 10, the diaphragm 2 is stopped down, and a light beam reflected by the quick return mirror 3 is partially passed through the reticle 4, the condenser lens 5, and the pentaprism 6 by the beam splitter 7. The light is guided to the re-imaging lens 9 to form an image on the solid-state imaging device 10.

FIG. 2 shows a solid-state imaging device 10 according to the first embodiment.
FIG. 4 is a block diagram showing a flow of data of a video image captured by the camera. The solid-state imaging device 10 is composed of, for example, a CCD (charge coupled device) or the like, and includes a driving circuit 13.
Thus, control such as setting of an accumulation time and an amplifier gain is performed, and the imaging data is read out by the drive circuit 13 and stored in the first memory 14.

The correction value calculation unit 18 receives a focal length of the lens from a microprocessor (not shown) in the taking lens 1.
The lens data 16 such as the exit pupil distance and the open F value,
The aperture value 17 set from the aperture ring of the lens or the camera body is read, and a correction value for correcting data of the solid-state imaging device 10 is calculated. The necessity of data correction and the method of calculating the correction value will be described later in detail.

The data correction section 15 corrects the video data stored in the first memory 14 with the correction value from the correction value calculation section 18 and stores the result in the second memory 19. The recording unit 20 is, for example, a replaceable card type S
It is a RAM, a flash memory, a hard disk, a floppy disk, or the like, and records video data stored in the second memory 19. The display unit 21 is, for example, a liquid crystal display panel or the like, displays video data in the second memory 19, and confirms a photographing result and performs viewing.

FIG. 3 is a diagram showing a display position of the display unit 21 of the first embodiment. As shown in FIG. 3, the display unit 21 includes a rear portion 21a of the camera 100, a top portion 21b above the pentaprism, a top left side 21c, and a top right side 21d.
Etc. can be provided. The display unit 21
As a separate component, it is connected independently to the camera 100 with a connection cord 102 for display, as in the monitor unit 101, or is fixed using a hot shoe 103 for fixing a speedlight, and an electrical contact 104 provided on the hot shoe is provided. The data may be transmitted from.

FIG. 4 is a diagram illustrating the number of imaging pixels of the solid-state imaging device 10 of the camera according to the first embodiment. In the camera as in the first embodiment, it is preferable that the number of pixels is about 640 × 480, which is the same as the VGA standard, which is a monitor display standard of a personal computer, and is about 300,000 pixels so that data can be captured and displayed on a personal computer or the like. However, recording in color requires three colors of R, G, and B. If these pixels are further divided into three as shown in FIG. 5, the number of pixels is tripled, and 900,000 pixels are required. Would.

Therefore, as shown in FIG. 6, a method of arranging G pixels contributing to the resolution in a checkered pattern and arranging R and B pixels therebetween is effective. In this case, since there is only one of the R, G, and B pixels in one pixel, the data of the other two non-existing colors may be obtained by complementing the surrounding pixels. For example, the pixel of (2,3) has only R, but the G of the pixel is (2,2), (1,3),
The average value of the G data of (3, 3) and (2, 4) is used.
The B data includes (1, 2), (3, 2), (1,
4) The average value of the B data of (3, 4) is used. Complementary data is obtained for other pixels in the same manner.

FIGS. 7 to 10 are diagrams for explaining that the image of the solid-state image sensor 10 as a secondary image is different from the image of the primary image. For simplicity of explanation, the pentaprism 6 is unfolded into a cylindrical shape and the quick return mirror 3
And the beam splitter 7 is omitted. Also, usually, the focusing screen 4 has a structure in which a diffusion plate and a Fresnel lens are combined, and the light flux of the lens is refracted by the action of both the focusing screen 4 and the condenser lens 5. The light beam was written as refracted between the reticle 4 and the condenser lens 5.

FIG. 7 is a diagram for explaining the center of the screen, that is, the point X1 on the optical axis. First, the exit pupil distance P
It is assumed that o is P1, and the lens L1 has a light beam having an F value having a spread of F1. Also, the F value is the same as L1,
Assume a lens L2 having an exit pupil distance of P2 longer than P1, and a lens L3 of P3 shorter than P1. The lenses L1, L2, and L3 form a light beam indicated by F1 on the reticle 4 at a point X1 on the optical axis.
The light beam of F1 that has passed through the reticle 4 spreads again as shown in the figure. After forming an image at the point X1 on the optical axis,
The light beam that reaches the re-imaging lens 9 has a spread of F2.

In this case, the lenses L1, L2, L3 are
Since both of them completely include the light beam F2, the light beam of the same light amount is re-imaged on the solid-state imaging device 10 regardless of which lens is mounted. At this time,
The illuminance of the point X1 on the reticle 4, which is the primary image plane, and the illuminance of the point X1 'on the solid-state imaging device 10, which is the secondary image plane, have a ratio corresponding to the square of the angle between F1 and F2. , And becomes constant irrespective of the attached lens.

Next, referring to FIG. 8, a description will be given of X2 which is a point around the screen, that is, a point which is distant to some extent from the optical axis. The lenses L1, L2, L3 are the same as those in FIG. The luminous flux focused on the point X2 by the lens L1 is represented by F
A light beam passing through 1 ′ and X2 and being imaged by the re-imaging lens 9 on the point X2 ′ on the solid-state imaging device 10 is defined as F2 ′. F
The light beam 2 'passes through the center of the lens L1 when the exit pupil distance Po is P1. This indicates that if the exit pupil distance Po is set to an appropriate value, the light flux around the screen may also pass through the center of the lens.

However, L having an F value equal to the lens L1
Even at 2, L3, if the exit pupil distance Po is different, the light beam does not pass through the center of the lens. Then, the lens L2
In the case of L3, the luminous flux reaching the solid-state imaging device 10 causes vignetting, and only the luminous flux of the hatched portions shown in FIGS. 9 and 10 respectively arrives. Therefore,
In the case of the lenses L2 and L3, the illuminance on the solid-state imaging device 10 decreases as going to the periphery compared to the lens L1. That is, in the case of the lens L1, the illuminance ratio between the reticle 4 and the solid-state imaging device 10 is constant regardless of the screen position, but in the case of the lenses L2 and L3, the illuminance of the solid-state imaging device 10 with respect to the reticle 4 Decreases as one goes to the periphery of the screen.

That is, the illuminance on the optical axis on the primary image plane is represented by S
1. The illuminance of one point at a certain peripheral is S2, and S1,
Assuming that the illuminances corresponding to S2 are S1 ′ and S2 ′, the ratio Z of the peripheral light amount reduction on the secondary image surface to the peripheral light amount reduction on the primary image surface is expressed by Expression 1.

Z = (S2 ′ / S1 ′) / (S2 / S1) (1)

This Z is related to the exit pupil distance Po of the lens, the aperture value F, and the distance h from the optical axis, as shown in FIG. That is, as shown in Equation 2, Z is P
It is a function of o, F and h.

Z = f (Po, F, h) (2)

However, in practice, it is very difficult to obtain Equation 2 by simulation because there are problems such as the diffusion of the light beam by the focusing screen 4 and the efficiency of the Fresnel lens provided on the focusing screen 4. is there. Therefore, in order to obtain Z corresponding to each photographing lens and aperture value, an illuminance ratio measurement experiment is performed using an actual optical system, Z is obtained based on the experiment result, and a data table is created or the experimental result is obtained. For example, a method of obtaining an approximate expression that corresponds to the above may be used.

Ideally, the value of Z is required by the number of imaging pixels, but it is difficult to store the same number of Z values in a solid-state imaging device having 300,000 pixels as shown in FIG. Therefore, pixels that are close to some extent are grouped, and the Z value of the group may be represented by only one, or the Z value may be thinned out and stored, and the Z value of an area of a pixel that is not stored may be stored. It may be obtained by complementing a plurality of Z values obtained.

Further, as can be seen from Equation 2, since the Z values of the pixels at the same distance from the optical axis may be the same, the number of Z values is only １ ／ of the number of pixels when simply considered.

Further, from the results of the measurement experiment, P
By learning a neural network that outputs a Z value as an input parameter such as o, F, and h and inputting these input values to the neural network to calculate the Z value, it is possible to reduce the number of pixels of all pixels with a small memory. The Z value can be determined. Neural networks are well known from a number of documents and will not be described here.

FIG. 12 is a flowchart showing the operation of the first embodiment. When a shutter release button (not shown) provided on the camera is pressed, this flowchart is executed, and the silver halide film 53 and the solid-state imaging device 1 are executed.
Exposure to zero is performed. Hereinafter, each step will be described.

In step S101, lens information (focal length, open F value, exit pupil distance, etc.) necessary for controlling the camera is read from a microprocessor incorporated in the taking lens. The number of steps of the aperture required for exposure control is read from the position of an aperture ring interlock lever (not shown) provided on the camera side.

In step S102, the aperture 2 of the photographing lens is narrowed down to the set value in accordance with the number of aperture steps read in from step S101. In S103, the imaging operation of the solid-state imaging device 10 is performed, and the imaging data is read. In S104,
The image data is stored in the first memory 14.

In S105, the quick return mirror 3
Up to a predetermined position. In step S106, the shutter 11 is set at the shutter speed set manually or automatically.
Is performed, and the silver halide film 12 is exposed. S1
At 07, when the exposure is completed, the quick return mirror 3 is returned to the original position. In S108, the diaphragm 2 is returned to the open position. In S109, the correction value Z of each pixel of the imaging data is calculated by the method described above.

In step S110, based on the obtained Z value,
Each pixel data in the first memory 14 is corrected and stored in the second memory 19. In S111, the data in the second memory 19 is stored in the recording unit 20. In S112, the data in the second memory 19 is displayed on the display unit 21.

According to the first embodiment as described in detail above, the following effects can be obtained. (1) In a camera having two exposure units, by compensating for a difference between the two images, a recorded or displayed image of one of the photographed results is confirmed, and an image of the other photographed result is displayed. The user can evaluate the photographing result without looking at it. (2) Since the silver halide film 12 is arranged in the first exposure unit and the solid-state imaging device 10 is arranged in the second exposure unit, it is possible to eliminate the difference between the images of both the solid-state imaging device 10 and the silver halide film 12. .

(3) Since the data correction unit 15 corrects the difference between the primary image and the secondary image caused by the light loss of the re-imaging lens 9, the difference due to the effect of the re-imaging lens 9 is eliminated. be able to. (4) The data correction unit 15 reduces the light amount of the secondary image with respect to the primary image due to the light loss of the re-imaging lens 9;
In particular, since the decrease in the peripheral light amount is corrected, it is possible to eliminate the difference in the image due to the decrease in the peripheral light amount of the secondary image.

(5) The recording unit 20 includes the data correction unit 15
The corrected secondary image is recorded, so that the corrected video can be recorded. (6) The display unit 21 displays the secondary image corrected by the data correction unit 15, so that the corrected video can be checked.

(Second Embodiment) FIG. 13 is a view showing a second embodiment of the camera according to the present invention. Note that the same reference numerals are given to portions that perform the same functions as those in the above-described first embodiment, and overlapping descriptions will be omitted as appropriate. In the first embodiment, after the pentaprism 6, the beam splitters 7,
Although the example in which the re-imaging lens 9 and the solid-state imaging device 10 are provided has been described, the second embodiment replaces the back cover of the single-lens reflex camera to provide a data bag, and
-1, the re-imaging lens 9-1 and the solid-state imaging device 10
-1 is arranged.

In this case, the exposure unit is the solid-state image pickup device 1
However, the solid-state imaging device 10-1 further converts the primary image formed by the imaging lens 1 into a re-imaging lens 9-1.
The data correction unit 15 corrects the difference between the primary image and the secondary image in the same manner as in the first embodiment.

At this time, the image picked up by the solid-state image pickup device 10-1 can be recorded by the recording unit 20 and can be displayed by the display unit 21. Therefore, according to the second embodiment, it is possible to record or display an image without a decrease in the amount of peripheral light.

(Modifications) Various modifications and changes are possible without being limited to the above-described embodiments, and they are also within the equivalent scope of the present invention. For example, in Expression 2, Z is a function of the exit pupil distance Po of the lens, the aperture value F, and the distance h from the optical axis. However, the reflectance of the half mirror 7 may be added to the parameter. Specifically, when the light amount ratio between transmission and reflection is 5: 5, a coefficient that becomes “2 times” may be applied. Therefore, it is possible to eliminate a difference in image due to a decrease in the amount of light of the entire secondary image.

[0049]

As described above in detail, according to the present invention, a secondary image can be accurately recorded or displayed even when there is a re-imaging optical system.

In a camera having two exposure units for exposing a first image and a second image which is a secondary image of the first image, a difference between the two images is corrected. Therefore, by evaluating the second video, which is a secondary image of the first video, the first video can be accurately evaluated without looking at the first video.

[Brief description of the drawings]

FIG. 1 is a diagram showing an optical system of a first embodiment of a camera according to the present invention.

FIG. 2 is a block diagram illustrating a data flow of the camera according to the first embodiment.

FIG. 3 is a diagram illustrating a display unit of the camera according to the first embodiment.

FIG. 4 is an explanatory diagram of a solid-state imaging device of the camera according to the first embodiment.

FIG. 5 is an explanatory diagram of a solid-state imaging device of the camera according to the first embodiment.

FIG. 6 is an explanatory diagram of a solid-state imaging device of the camera according to the first embodiment.

FIG. 7 is a diagram illustrating a difference between a primary image and a secondary image of the camera according to the first embodiment.

FIG. 8 is a diagram illustrating a difference between a primary image and a secondary image of the camera according to the first embodiment.

FIG. 9 is a diagram illustrating a difference between a primary image and a secondary image of the camera according to the first embodiment.

FIG. 10 is a diagram illustrating a difference between a primary image and a secondary image of the camera according to the first embodiment.

FIG. 11 is an explanatory diagram of Z value parameters of the camera according to the first embodiment.

FIG. 12 is a flowchart illustrating an algorithm of the camera according to the first embodiment.

FIG. 13 is a diagram showing an optical system of a camera according to a second embodiment of the present invention.

FIG. 14 is a diagram showing a conventional technique.

FIG. 15 is a diagram showing a conventional technique.

FIG. 16 is a diagram showing a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shooting lens 2 Aperture 3 Quick return mirror 4 Focusing plate 5 Condenser lens 6 Pentaprism 7 Beam splitter 8 Eyepiece 9 Reimaging lens 11 Shutter 12 Silver halide film 13 Drive circuit 14 First memory 15 Data correction unit 16 Lens data 17 Aperture value 18 Correction value calculation unit 19 Second memory 20 Recording unit 21 Display unit

Claims (9)

[Claims] An exposure unit for exposing a primary image formed by a photographing optical system and a secondary image formed by a re-imaging optical system; and recording an image exposed on the exposure unit. A camera comprising: a recording unit; and a correction unit that corrects a difference in video between the primary image and the secondary image. 2. An exposure unit for exposing a primary image formed by a photographing optical system and a secondary image formed by a re-imaging optical system, and an image exposed on the exposure unit. A camera comprising: a display unit; and a correction unit that corrects a difference in video between the primary image and the secondary image. 3. A first exposure unit to which a primary image formed by a photographing optical system is exposed, and a secondary image formed by further forming the primary image formed by the photographing optical system by a re-imaging optical system. A second exposure unit that exposes an image, a recording unit that records an image exposed to the second exposure unit, and a correction unit that corrects a difference in image between the primary image and the secondary image. camera. 4. A first exposure section to which a primary image formed by a photographing optical system is exposed, and a secondary image formed by further forming the primary image formed by the photographing optical system by a re-imaging optical system. A second exposure unit that exposes an image, a display unit that displays an image exposed to the second exposure unit, and a correction unit that corrects a difference in image between the primary image and the secondary image. camera. 5. The camera according to claim 3, wherein a silver halide film is disposed in the first exposure unit, and a solid-state imaging device is disposed in the second exposure unit. And the camera. 6. Any one of claims 1 to 5
The camera according to claim 1, wherein the correction unit corrects a difference in video between the primary image and the secondary image due to light loss of the re-imaging optical system. 7. One of claims 1 to 6
The camera according to claim 1, wherein the correction unit corrects a total or partial decrease in light amount of the secondary image with respect to the primary image due to light loss of the re-imaging optical system. . 8. The camera according to claim 1, wherein the recording unit records the secondary image corrected by the correction unit. Camera. 9. The camera according to claim 2, wherein the display unit displays the secondary image corrected by the correction unit. Camera.