JPH06201976A - Camera lens device and camera system - Google Patents

Abstract

PURPOSE:To provide a lens device for an autofocusing camera and a camera system which are perfectly interchangeable with any camera even in the case the camera (autofocusing technique) is progressed. CONSTITUTION:In this camera lens device 1 provided with a photographing optical system 5, a lens driving means 7 driving the photographing optical system to perform focusing, a storage means 6 storing the information of the photographing optical system, and a transfer means transferring the information stored in the means 6 to a camera body device 2; the radius of curvature, the spacing between faces and the refractive index of the photographing optical system are included in the information stored in the means 6. The camera body device 2 is provided with a range-finding means 9 detecting the focusing position of the photographing optical system and an arithmetic control means 11 calculating the driving amount of the photographing optical system to perform focusing, and the means 11 calculates the driving amount of the photographing optical system basing on an output detection signal detected by the range-finding means and the information concerning the radius of curvature, the spacing between faces and the refractive index of the photographing optical system previously stored in the means 6 in the camera lens device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera lens device and a camera system.

[0002]

2. Description of the Related Art In recent years, automatic focusing of single-lens reflex cameras is rapidly becoming widespread, and various techniques relating to this have been proposed. The so-called phase difference detection method is generally used as the autofocus method for this single-lens reflex camera, and various techniques have been developed to achieve faster and more accurate focusing by this method. .

That is, for example, a table for knowing the amount of movement of the image plane from the amount of movement of the focusing lens is stored in the storage means built in the lens barrel, and the focus shift amount measured by the focus detection device and the above By calculating the movement amount of the focusing lens in advance from the table stored in the storage means, a technique for achieving a faster and smoother focusing, and a light flux used in the focus detection device is The amount of deviation between the actual best image plane position of the taking lens and the focus position expected to be detected by the focus detection device due to the fact that only part of the light flux is used is stored in the lens barrel. Techniques and the like have been proposed in which a more accurate focus can be obtained by holding it by a means.

[0004]

However, the recent autofocus technology has made great strides, for example, a technology capable of performing distance measurement not only at the center of the screen but also at the periphery of the screen,
Techniques and the like have been provided that can provide an extremely wide range-finding area.

In order to enable accurate distance measurement even in the peripheral portion of the screen in this way, for example, the image plane position including the field curvature aberration at an arbitrary image height of the mounted photographing lens, and the axis. Information such as the position of the exit pupil of the external ray is also required, and therefore, this information must also be stored in the storage means in the lens barrel.

As described above, with the progress of the autofocus technology,
There is a problem that the amount of information to be stored in the storage means in the lens barrel becomes enormous.

Further, the mechanical service life of the lens barrel is considerably longer than that of the camera body. However, in the case of an autofocus camera lens, as described above, the progress of the camera (autofocus technology) is improved. As a result, the memory content that should be stored in the lens changes, so even though it operates mechanically completely within its useful life, the memory content in the lens becomes insufficient when it is attached to a new camera body. Alternatively, there is a problem that the autofocus mechanism may not operate normally due to the difference.

The present invention has been made to solve the above problems in the conventional autofocus single-lens reflex camera. Even if the camera (autofocus technology) advances, it is not affected by the advance and the progress is made. It is an object of the present invention to provide a lens device for an autofocus camera and a camera system that are completely compatible with the above-mentioned camera (autofocus technology).

[0009]

[Means for Solving the Problems] To achieve the above object,
According to a first aspect of the present invention, a photographing optical system that forms an image of a subject light on a film surface, a lens driving unit that drives the photographing optical system for focusing, and a storage unit that stores information of the photographing optical system. And a transfer means for transferring the information stored in the storage means to the camera body device, in the information stored in the storage means, the radius of curvature of the photographing optical system, the surface spacing, and The present invention relates to a camera lens device including a refractive index.

The second invention of the present application comprises distance measuring means for detecting the focus position of the photographing optical system, and arithmetic control means for calculating the drive amount of the photographing optical system for focusing. The control means controls the photographing optical system from the output detection signal detected by the distance measuring means and the information about the radius of curvature, the surface distance, and the refractive index of the photographing optical system stored in advance in the storage means in the camera lens device. The present invention relates to a camera body device, characterized in that it calculates a driving amount of

Further, a third invention of the present application is a camera system comprising a camera lens device according to the first invention of the present application and a camera body device according to the second invention of the present application. It is related.

Further, a fourth invention of the present application is the camera system according to the third invention of the present application, further comprising detection means for detecting that the camera lens device is attached to the camera body device, and the detection means is provided. Based on the detection signal of the means, the information stored in the storage means in the camera lens device is transferred to the storage means provided in the camera body device through the transfer means, and from the transferred information, The present invention relates to a camera system, wherein an arithmetic control unit calculates information necessary for focusing of the mounted camera lens device.

[0013]

According to the present invention having such a configuration, in the storage means provided in the camera lens device, the radius of curvature of the photographic optical system, the surface spacing, and the refractive index (hereinafter Are collectively referred to as “lens data”). This lens data is transferred to the camera body device by the transfer means.

Further, in the camera body device according to the second to fourth inventions of the present application, the focus position of the photographing optical system is detected by the distance measuring means, and this output detection signal is taken into the arithmetic control means. . Then, the calculation control means determines the focus from the output detection signal from the distance measuring means and the lens data (curvature radius, surface distance, and refractive index) of the photographing optical system taken from the storage means of the camera lens device. Is calculated, and the focusing control of the photographing optical system is performed based on the calculated value.

As described above, in the present invention, the data necessary for ray tracing of the photographic optical system (radius of curvature of each surface of the photographic optical system, surface spacing, and refractive index) is completely stored in the storage means as the lens data. Therefore, by taking this lens data into the arithmetic and control means of the camera body, it is possible to calculate the focusing data required by the camera for any camera body device.

Therefore, unlike the conventional system in which various specifications of the lens are stored in advance in the storage means in the lens barrel, the lens is used even when the focusing technology advances and new specifications are required. And can maintain compatibility with the new camera body.

In the present invention, the lens data includes the radius of curvature of the photographic optical system, the surface spacing, and the refractive index. However, in addition to these, the effective diameter of the photographic optical system may be included. .

Further, in the camera system according to the fourth aspect of the present application, the detection means detects that the camera lens device is attached to the camera body device, and the camera lens is detected based on the detection signal. The lens data stored in the storage means in the apparatus is transferred to the storage means provided in the camera body apparatus through the transfer means, and the arithmetic control means is mounted from the transferred lens data. The information of the camera lens device is calculated.

As described above, according to this system, since the lens data is transferred and the information necessary for focusing the camera lens device is calculated at the same time when the lens is mounted, the so-called time lag in the operation of the camera is minimized. This enables quick focusing and shooting.

[0020]

Embodiments of the present invention will be described with reference to the drawings. Figure 1
2 is an explanatory diagram showing a configuration of a camera system according to an embodiment of the present invention, and FIG. 2 is a flowchart showing an operation of the camera system.

As shown in FIG. 1, the camera lens system according to this embodiment comprises a lens barrel 1 and a camera body 2, and the lens barrel 1 is detachably attached to the camera body 2 by a mount 3. . The lens barrel 1 is optically coupled to the camera body 2 through the opening 3 a of the mount 3 and electrically coupled to the camera body 2 through the electrical contacts 4.

The lens barrel 1 is provided with a photographing optical system 5, a storage element 6 having lens data of the photographing optical system 5 as a main memory content, and a drive system 7 for driving and controlling the photographing optical system 5. Has been. The storage element 6 is composed of a ROM and has a drive system 7
Is composed of a motor for converting electric signals into mechanical power and its control circuit. Although the drive system 7 is provided in the lens barrel 1 in this embodiment, the drive system is provided in the camera body 2 so that the drive system 7 is linked with the optical system in the lens barrel by a shaft, a gear and the like. Of course, it is okay.

The camera body 2 has a photometric element 8 for measuring the brightness of a subject, a distance measuring element 9 for focus detection,
An arithmetic processing unit (CPU) 11 that controls the photographing optical system 5 based on the information from these elements, and a storage element 10 for storing information necessary for the arithmetic processing are provided.

The photometric element 8 comprises a condenser lens and a gallium photodiode (GPD) or silicon photodiode (SPD) for converting the condensed light into an electric signal. The distance measuring element 9 is a film. It is composed of a lens for forming a subject image at a position conjugate with the surface 13 and an element such as a CCD for judging the image forming position.

The storage element 10 in the camera body is an RO in which information for controlling the entire camera is stored in advance.
M and a RAM for storing the lens data transferred from the mounted lens 1 and the calculation result calculated by the calculation control unit 11.

In the camera system according to the present embodiment having the above-described structure, the sequence shown in FIG. 2 is performed. That is, when the lens 1 is mounted in step 201 while the power of the camera is on, step 2
At 02, information such as lens data is transferred from the lens storage element 6 to the camera body storage element 10.

When the transfer of the data is completed, step 2
In 03, the arithmetic control unit 11 takes in the transferred lens data in the storage element 10 of the camera body, and from the data, various lens specifications, for example, the driving amount and the focus position of the mounted lens 1 are calculated. The relationship (ratio) and the information necessary for correcting the focus due to the aberration are calculated.

The result of this calculation is step 204.
Then, it is stored in the storage element 10 of the camera, and the photographing standby state of step 205 is entered.

When the photographer half-presses the so-called shutter for taking a picture (step 206), the operations of the photometric element 8 and the distance measuring element 9 are started in step 207, and the distance measuring element 9 is operated in step 208. In step 203, the driving amount of the lens is calculated from the calculation result calculated by the calculation control unit 11, and in step 209, the lens is driven based on the calculation result and focusing is performed.

Then, in step 210, when the focus is proper, the release standby state (step 211) is set,
On the other hand, if it is inappropriate, the process returns to step 208, the lens driving amount is calculated again, and the lens driving is performed based on the calculation result.

In the camera system of this embodiment, as described above, the lens data in the camera storage element 6 is transferred to the storage element 10 in the camera body, and the arithmetic control unit 11 in the camera body performs various kinds of focusing. Since the element is calculated, the parameters according to the grade of the camera and the required accuracy are obtained, and therefore, the compatibility of the lenses is completely maintained even in different camera bodies.

However, since the transfer of the lens data and the calculation of various specifications are started at the same time as the lens is mounted, the load on the calculation control unit is reduced and the so-called time lag in camera operation can be minimized. It enables quick focusing and shooting.

In other words, as soon as the lens is exchanged, the shutter release is not considered, and normally the work of holding the camera and determining the composition is performed before performing the shutter release. Since the lens data can be transferred and various specifications can be calculated, and therefore the processing capacity of the arithmetic control unit 11 can be used only for calculating the various specifications, the arithmetic processing can be performed in a shorter time. It becomes possible.

The camera data may be transferred by parallel transfer or serial transfer, but the parallel transfer method enables data transfer at a higher speed, while the serial transfer method may be used. If so, the number of electrical contacts between the camera body and the lens can be reduced, and the reliability can be improved.

Further, in order to further improve the processing capability of the arithmetic control unit, two CPUs, a CPU for calculating lens specifications and a CPU for controlling the camera, may be provided.

Further, since the camera lens device is provided with the lens data in the memory element 6, for example, in the product inspection process, when the inspection device is attached to various inspection devices and the inspection is performed, the inspection device is used as the lens data. By making it possible to read and perform ray tracing calculation, the difference between the performance of the manufactured product and the design performance can be immediately determined, and automation of product inspection and labor saving can be realized.

Further, the present invention can be applied not only to the camera system described above, but also to an optical system incorporated in various devices, a microscope lens, and the like.

[0038]

As described above, according to the present invention,
Even if a camera (autofocus technology) advances, it is possible to realize a lens device for an autofocus camera and a camera system that are completely unaffected by the advance and are completely compatible with the advanced camera (autofocus technology). .

[Brief description of drawings]

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

FIG. 2 is a flowchart showing an operation of the camera system according to the embodiment of the present invention.

[Explanation of symbols]

 1 lens barrel (camera lens device) 2 camera body 3 mount 3a mount opening 4 electrical contact 5 photographing optical system 6 storage element 7 lens drive system 8 photometric element 9 distance measuring element 10 storage element 11 arithmetic control unit (CPU) 12 Finder optical system 13 film

Claims (4)

[Claims] 1. A photographing optical system for forming an image of a subject light on a film surface, a lens driving unit for driving the photographing optical system for focusing, a storage unit for storing information of the photographing optical system, In a camera lens device including a transfer unit that transfers information stored in a storage unit to a camera body device, information stored in the storage unit includes a curvature radius, a surface distance, and a refractive index of the photographing optical system. A camera lens device characterized in that it is included. 2. A distance measuring means for detecting a focus position of the photographing optical system, and an arithmetic control means for calculating a driving amount of the photographing optical system for focusing, wherein the arithmetic control means is the distance measuring means. The drive amount of the photographing optical system is calculated from the output detection signal detected by the camera and the information about the radius of curvature, the surface distance, and the refractive index of the photographing optical system stored in advance in the storage unit in the camera lens device. A camera body device characterized in that 3. A camera system comprising the camera lens device according to claim 1 and the camera body device according to claim 2. 4. A detection means for detecting that the camera lens device is attached to the camera body device, and stored in the storage means in the camera lens device based on a detection signal of the detection means. The information is transferred to the storage means provided in the camera body device through the transfer means, and the calculation control means calculates information necessary for focusing of the mounted camera lens device from the transferred information. The camera system according to claim 3, wherein: