JP2004093786A - Camera system and interchangeable lens - Google Patents

Abstract

An object of the present invention is to provide a camera system which can be equipped with an interchangeable lens having a mechanical light amount adjusting mechanism and a light amount adjusting mechanism using a physical element, to perform appropriate light amount adjusting control after sufficiently exhibiting the performance of the entire system. Provide a camera system and interchangeable lens that can be used.
In a camera system having a camera body and an interchangeable lens that can be attached to and detached from the camera body, a first light source capable of controlling the amount of transmitted light by mechanically changing an opening area on the interchangeable lens side. Light amount adjusting means, second light amount adjusting means capable of controlling the amount of transmitted light using a physical element capable of adjusting the light transmission state, and information on the light amount adjusting capabilities of the first and second light amount adjusting means. Transmitting means for transmitting the light to the camera body; light measuring means for detecting the brightness of the subject; and the light amount adjusting ability of the first and second light amount adjusting means transmitted from the interchangeable lens and the output of the light measuring means; Command means for transmitting a light quantity adjustment command to the interchangeable lens based on the information about
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a camera system and an interchangeable lens in a silver halide camera, a video camera, a digital camera and the like of an interchangeable lens system, and particularly to a control method of a light amount adjusting mechanism provided in an optical path.
[0002]
[Prior art]
Conventionally, as described in, for example, Japanese Patent Application Laid-Open No. 2000-227618, a light amount adjusting mechanism using a physical element capable of adjusting light transmission characteristics represented by an electrochromic element (hereinafter referred to as an EC element) has been proposed. There has been proposed an example of a video camera which is used in combination with a light amount adjusting mechanism capable of mechanically changing an opening area. The above publication discloses a mechanical light amount adjusting mechanism when an incident light amount to a photographing optical system is equal to or less than a predetermined light amount. However, there is described an example in which when the light amount is equal to or more than a predetermined light amount, a mechanical light amount adjustment mechanism and a light amount adjustment mechanism using a physical element are used in combination to control the amount of light incident on the image sensor to be appropriate.
[0003]
[Problems to be solved by the invention]
However, in the above-described conventional example, since the mechanical light amount adjusting mechanism and the light amount adjusting mechanism using the physical element are controlled only based on preset information, the exchange is assumed to be used in various combinations. When applied to a lens-type camera system, there are the following problems. For example, in the case of a system in which two interchangeable lenses having different light amount adjustment capabilities can be used by attaching them to two camera bodies having different specifications, a photometry unit in which each camera body detects the brightness of a subject. The light amount adjustment command determined based on the output of the first lens needs to be a command that can be controlled by either of the two interchangeable lenses.
[0004]
For that purpose, the information preset in the two camera bodies must be adapted to the interchangeable lens with low light intensity adjustment capability, and as a result, the interchangeable lens with high light intensity adjustment capability It was a system that could not perform the appropriate light amount adjustment by taking advantage of the performance of.
[0005]
A third camera body in which information suitable for an interchangeable lens having a high light amount adjusting capability is set in advance in such a system (the performance of the interchangeable lens having a high light amount adjusting capability can be utilized). Is added, the combination of the third camera body and the interchangeable lens having a low light amount adjusting ability causes the camera body to command light amount adjustment exceeding the ability of the interchangeable lens, thereby performing appropriate light amount adjustment control. Because of this, it was impossible to maintain the compatibility of the entire system.
[0006]
The present invention has been made in view of such a problem, and in a camera system that can be mounted with an interchangeable lens having a mechanical light amount adjusting mechanism and a light amount adjusting mechanism using a physical element, the performance is fully exhibited throughout the entire system. It is another object of the present invention to provide a camera system and an interchangeable lens that can perform appropriate light amount adjustment control.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a camera system according to the present invention is a camera system having a camera body and an interchangeable lens that is detachable from the camera body, wherein the interchangeable lens mechanically changes an opening area. A first light amount adjusting means capable of controlling the amount of transmitted light by using a light emitting element; a second light amount adjusting means controlling the amount of transmitted light by using a physical element capable of adjusting the light transmission state; Transmitting means for transmitting information relating to the light amount adjusting capability of the light amount adjusting means to the camera body, wherein the camera body transmits light from the interchangeable lens to a photometric means for detecting the luminance of the subject; Command means for transmitting a light quantity adjustment command to the interchangeable lens based on the information on the light quantity adjustment capabilities of the first and second light quantity adjustment means.
[0008]
Further, it is preferable that the information on the light quantity adjusting ability is data on at least a maximum and a minimum opening area controllable by the first light quantity adjusting means and a variable range of the transmitted light quantity by the second light quantity adjusting means.
[0009]
The information on the light amount adjusting ability may include data on a variable region of the transmitted light amount in the second light amount adjusting means.
[0010]
Further, it is preferable that the information on the light quantity adjusting ability includes data on a minimum variable width of the transmitted light quantity in at least one of the first and second light quantity adjusting means.
[0011]
The interchangeable lens according to the present invention is an interchangeable lens that can be attached to and detached from the camera body, the first light amount adjusting means capable of controlling the amount of transmitted light by mechanically changing the opening area, A second light amount adjusting unit that controls the amount of transmitted light using a physical element whose state can be adjusted; and a transmitting unit that transmits information on the light amount adjusting capabilities of the first and second light amount adjusting units to the camera body. And controlling the first and second light quantity adjusting means based on a light quantity adjustment command from the camera body.
[0012]
Further, it is preferable that the information on the light quantity adjusting ability is data on at least a maximum and a minimum opening area controllable by the first light quantity adjusting means and a variable range of the transmitted light quantity by the second light quantity adjusting means.
[0013]
It is preferable that the information on the light quantity adjusting ability includes data on a variable area of the transmitted light quantity in the second light quantity adjusting means.
[0014]
In addition, the information on the light amount adjusting ability may include data on a minimum variable width of the transmitted light amount in at least one of the first and second light amount adjusting means.
[0015]
With the above configuration, the camera body can determine the light intensity adjustment command according to the light intensity adjustment capability of each interchangeable lens. Can be performed.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a camera system and an interchangeable lens which are embodiments of the present invention will be described in detail.
[0017]
FIG. 1 is a functional block diagram of the camera system according to the embodiment. In FIG. 1, reference numeral 1 denotes a camera body, and 2 denotes a lens body.
[0018]
First, the configuration of the lens body 2 will be described. Reference numeral 3 denotes a photographing lens as a photographing optical system; 16, a mechanical diaphragm capable of mechanically changing an aperture area for a photographing light beam; 17, a third driver circuit for supplying driving power from the lens microcomputer 7 to the mechanical diaphragm 16; It is. Reference numeral 4 denotes an EC element as a physical element capable of adjusting light transmittance. The EC element 4 includes a first EC area 5 in an inner area of a light beam passing through a minimum aperture diameter controllable by a mechanical aperture 16. The second EC area 6 is provided in the outer area of the light beam passing through the maximum aperture diameter that can be controlled by the mechanical aperture 16, and in the present camera system, the opening area of the mechanical aperture 16 is changed and the aperture area of the mechanical aperture 16 is changed. By changing the light transmittance of the second EC area 6 while minimizing the value, it is possible to appropriately adjust the amount of transmitted light from the subject through the imaging lens 3 and reaching the image sensor 14 described later.
[0019]
Reference numeral 7 denotes a lens microcomputer which controls all the controls on the lens body 2, 8 denotes an electrically erasable storage element EEPROM for storing various histories and data relating to the lens through communication with the lens microcomputer 7, and 9 denotes a first EC from the lens microcomputer 7. A first driver circuit 10 for applying drive power to the area 5 is a second driver circuit for applying drive power from the lens microcomputer 7 to the second EC area 6, and 11 is a power supply from the first driver circuit 10. A photo-interrupter 12 for detecting the light transmittance of the second EC area 6 driven by the lens microcomputer 12 is a lens contact unit having a contact for the lens microcomputer 7 to communicate with the camera body 1. Next, the configuration of the camera body 1 will be described.
[0020]
Reference numeral 13 denotes a camera microcomputer that controls all the controls related to the camera body 1, and 14 denotes a photographing lens 3, a mechanical aperture 16, and a first EC for photographing and recording, for detecting an in-focus state, and for detecting a subject luminance in accordance with instructions from the camera microcomputer 13. An image sensor for detecting the state of a photographic light beam that has passed through the area 5, a camera contact unit 15 having a contact for the camera microcomputer 13 to communicate with the lens body 2, and the lens body 2 attached to the camera body 1 In this case, the lens contact unit 12 and the camera contact unit 15 are electrically connected.
[0021]
FIG. 2 is a flowchart of the camera system according to the embodiment of the present invention. Control of the embodiment will be described with reference to FIG. In step 101, when the camera body 1 is instructed from the outside to appropriately adjust the amount of incident light from a subject that reaches the image sensor 14, in step 102, the camera microcomputer 13 sends the mechanical aperture 16 and the In step 103, the lens microcomputer 7 requests the controllable maximum and minimum opening areas of the mechanical diaphragm 16 stored in the EEPROM 8, and controls the EC element 4. The data of the range of the light transmittance, the minimum variable width of the transmitted light amount in the mechanical diaphragm 16 and the first EC area 5 is transmitted to the camera microcomputer 13.
[0022]
In step 104, the camera microcomputer 13 reads out the current luminance information of the photographing light beam from the image sensor 14, and sets the exposure time and the aperture diameter of the mechanical diaphragm 16 (the maximum value transmitted in step 103) as the control targets in the photographing operation. (Smaller than the aperture diameter and satisfying the minimum variable width). In step 105, the camera microcomputer 13 compares the aperture diameter of the mechanical diaphragm 16 determined in step 104 as the control target with the minimum controllable aperture diameter transmitted in step 103, and proceeds to step 107 if smaller, and proceeds to step 107 if larger. Go to 115.
[0023]
In step 107, the camera microcomputer 13 changes the control target of the aperture of the mechanical diaphragm 16 to the minimum controllable aperture transmitted in step 103. In step 108, the camera microcomputer 13 changes the control target of the mechanical diaphragm 16. The target light transmittance of the first EC area 5 (satisfying the minimum variable width transmitted in step 103) required to correct the deviation from the proper exposure caused by changing the value and to obtain the proper exposure again is set. decide.
[0024]
In step 109, the camera microcomputer 13 compares the transmittance of the first EC area 5 determined as the control target with the minimum controllable light transmittance. If the transmittance is larger, the process proceeds to step 110; A combination of the exposure time and the aperture diameter of the mechanical diaphragm 16 different from the previous time is determined. In step 110, the camera microcomputer 13 transmits the control target aperture diameter of the mechanical diaphragm 16 determined in step 107 to the lens microcomputer 7, and the lens microcomputer 7 receives it. In step 111, the camera microcomputer 13 transmits the target light transmittance of the first EC area 5 determined in step 108 to the lens microcomputer 7, and the lens microcomputer 7 receives it.
[0025]
In step 112, the lens microcomputer 7 reads the drive characteristics (eg, drive voltage-light transmittance characteristics, drive voltage application time-light transmittance characteristics) of the first EC area 5 and the second EC area 6 stored in the EEPROM 8, According to these characteristics, the driving power is supplied to the first EC area 5 and the second EC area 6 via the first driver circuit 9 and the second driver circuit 10, and the output of the photo interrupter 11 for detecting the light transmittance of the second EC area 6 The light transmittance of the first EC area 5 that can be estimated from the above is driven to the target light transmittance transmitted in step 111.
[0026]
In step 113, the lens microcomputer 7 supplies driving power to the mechanical aperture 16 via the third driver circuit 17, and drives the aperture of the mechanical aperture 16 to the target aperture transmitted in step 110. In step 115, the camera microcomputer 13 transmits the control target aperture of the mechanical diaphragm 16 determined in step 106 to the lens microcomputer 7, and the lens microcomputer 7 receives it. In step 114, the lens microcomputer 7 transmits the setting end of the aperture diameter of the mechanical diaphragm 16 and the light transmittance of the first EC area 5 to the camera microcomputer 13 and ends the operation.
[0027]
According to the camera system of the embodiment of the present invention, by transmitting information about the light amount adjustment capabilities of the mechanical diaphragm 16 and the first EC area 5 from the interchangeable lens side detachable to the camera body to the camera body side, The light intensity adjustment command determined by the camera body can be adapted to the light intensity adjustment capability of each interchangeable lens. It becomes possible.
[0028]
In addition, the information on the light amount adjusting ability is determined on the camera body side by using at least the maximum and minimum controllable opening areas in the mechanical diaphragm 16 and the controllable light transmittance range in the first EC area 5. The range in which the amount of transmitted light is controlled by changing the opening area of the mechanical diaphragm 16 and the range in which the amount of transmitted light is controlled by changing the light transmittance of the first EC area 5 can be determined as the optimum range for each interchangeable lens. Thus, it is possible to perform appropriate light amount adjustment control while sufficiently exhibiting performance over the entire system.
[0029]
Further, the information on the light amount adjustment ability is information including data on the minimum variable width of the transmitted light amount in the mechanical diaphragm 16 and the first EC area 5, so that the opening area of the mechanical diaphragm 16 and the first EC determined by the camera body side are determined. The control target of the light transmittance in the region 5 can be determined with the optimum accuracy for each interchangeable lens, so that it is possible to perform appropriate light amount adjustment control while sufficiently exhibiting performance over the entire system. .
[0030]
In the above embodiment, the first EC area 5 is provided in the inner area of the light beam passing through the smallest aperture diameter that can be controlled by the mechanical aperture 16, and the opening area of the mechanical aperture 16 is changed and the aperture of the mechanical aperture 16 is changed. An example is described in which the light transmittance of the first EC area 5 is changed while minimizing the area to appropriately adjust the amount of transmitted light that reaches the image sensor 14 from the subject through the imaging lens 3. The present invention is not limited to this. The first EC region 5 is provided in a region larger than the light beam passing through the smallest opening area controllable by the mechanical diaphragm 16, and the amount of transmitted light is changed by changing the opening area of the mechanical diaphragm 16. Utilizing the overlapping of the controllable range and the range in which the amount of transmitted light can be controlled by changing the light transmittance of the first EC area 5, for example, a shooting mode (field prioritized in the field of view) described in JP-A-10-042190. It is also possible to perform the control in accordance with the over-de blurred taste priority mode).
[0031]
In this case, the information on the light amount adjustment capability is information including data on the variable region of the transmitted light amount in the first EC region 5 so that the aperture area of the mechanical diaphragm 16 determined on the camera body side and the light in the first EC region 5 are changed. The combination of the transmittances can be determined within the optimum range for each interchangeable lens, and it is possible to perform appropriate light amount adjustment control while sufficiently exhibiting performance over the entire system.
[0032]
【The invention's effect】
As described above, according to the inventions of the present application, in a camera system including a camera body and an interchangeable lens that is detachable from the camera body, the amount of transmitted light can be reduced by mechanically changing the aperture area toward the interchangeable lens. A first light amount adjusting means capable of controlling, a second light amount adjusting means capable of controlling a transmitted light amount using a physical element capable of adjusting a light transmission state, and first and second light amounts A transmitting unit for transmitting information on the light amount adjusting capability of the adjusting unit to the camera body; a photometric unit for detecting the brightness of the subject; and a first and a second unit transmitted from the output of the photometric unit and the interchangeable lens. And a command means for transmitting a light quantity control command to the interchangeable lens based on the information on the light quantity control capability of the second light quantity control means. Can determine the light amount adjustment command corresponding to the force, after sufficiently exhibit performance over systems in general, it is possible to perform appropriate light amount adjustment control.
[Brief description of the drawings]
FIG. 1 is a functional block diagram of a camera system according to an embodiment of the present invention.
FIG. 2 is a flowchart of the camera system.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Camera main body 2 Lens main body 3 Shooting lens 4 EC element 5 First EC area 6 Second EC area 7 Lens microcomputer 8 EEPROM
9 First Driver Circuit 10 Second Driver Circuit 11 Photo Interrupter 12 Lens Contact Unit 13 Camera Microcomputer 14 Image Sensor 15 Camera Contact Unit 16 Mechanical Aperture 17 Third Driver Circuit

Claims (8)

A camera system having a camera body and an interchangeable lens detachable from the camera body,
A first light amount adjusting unit capable of controlling a transmitted light amount by mechanically changing an opening area;
Second light amount adjusting means for controlling the amount of transmitted light using a physical element capable of adjusting the light transmission state,
Transmitting means for transmitting information relating to the light amount adjusting capabilities of the first and second light amount adjusting means to the camera body;
The camera body is a photometric unit that detects the brightness of the subject,
Command means for transmitting a light amount adjustment command to the interchangeable lens based on an output value from the photometric means and information on the light amount adjustment capabilities of the first and second light amount adjustment means transmitted from the interchangeable lens. Characterized camera system. 2. The information on the light quantity adjusting ability is data on at least the maximum and minimum opening areas controllable by the first light quantity adjusting means and the variable range of the transmitted light quantity by the second light quantity adjusting means. The camera system according to 1. 3. The camera system according to claim 2, wherein the information on the light amount adjusting ability includes data on a variable region of a transmitted light amount in the second light amount adjusting unit. 4. 4. The camera system according to claim 2, wherein the information on the light amount adjusting ability includes data on a minimum variable width of a transmitted light amount in at least one of the first and second light amount adjusting units. 5. An interchangeable lens that can be attached to and detached from the camera body,
First light amount adjusting means capable of controlling the amount of transmitted light by mechanically changing the opening area;
Second light amount adjusting means for controlling the amount of transmitted light using a physical element capable of adjusting the light transmission state,
Transmitting means for transmitting information relating to the light amount adjusting capabilities of the first and second light amount adjusting means to the camera body;
An interchangeable lens, wherein the first and second light amount adjusting means are controlled based on a light amount adjustment command from the camera body. 6. The information relating to the light amount adjusting ability is data relating to at least a maximum and minimum opening area controllable by the first light amount adjusting unit and a variable range of the transmitted light amount in the second light amount adjusting unit. The interchangeable lens described in. 7. The interchangeable lens according to claim 6, wherein the information on the light amount adjusting ability includes data on a variable region of the transmitted light amount in the second light amount adjusting unit. 8. The interchangeable lens according to claim 6, wherein the information on the light amount adjusting ability includes data on a minimum variable width of a transmitted light amount in at least one of the first and second light amount adjusting units. 9.

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