JPH0268529A - Camera device and interchangeable lens - Google Patents

Abstract

PURPOSE:To easily replace a lens by providing a memory for storing identification data for identifying characteristics in a lens part, and altering and adjusting stop control according to the identification data when the lens is mounted on the camera. CONSTITUTION:When the mount 16 of the lens part 10 is mounted on the mount 32 of a camera main body 30, electric contacts 18 and 34 are connected and a microcomputer 48 reads stored data out of the memory 22 where the data for identifying the kinds of a stop and a stop driving mechanism 20 are written. Consequently, the gain of an amplifier 44 and the time constant of a variable time constant circuit 46 are adjusted by the microcomputer 48 to values corresponding to the characteristics of the lens part 10. Thus, the stop control over the interchangeable lens is altered and adjusted according to the stop characteristics, so interchangeable lenses having various characteristics are used for one camera main body and easily changed without any manual adjustment.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a camera device with interchangeable lenses and its interchangeable lenses.

[Conventional technology]

Camera devices in which a lens portion and a camera body portion are removable so that a plurality of interchangeable lenses can be used are well known in the field of video cameras as well as silver halide film single-lens reflex cameras.

In the lens exchange system, the interchangeable lens is the photographic lens,
The interchangeable lens is composed of a zoom drive section, an aperture, an aperture drive mechanism, and a mount section, and the mount section is mechanically coupled to a similar mount section on the camera body, thereby attaching the interchangeable lens to the same mount section on the camera body.

In addition, aperture information is exchanged between the interchangeable lens and the camera body.
A system for transmitting and receiving signals such as control information for automatic focusing is known, and in such a system, the electrical connection of the signal line is made by connecting the electrical contacts of both mounts, or by using an external cable or connector. It has been realized.

Note that, as the interchangeable lens, for example, a plurality of types of lenses with different focal lengths, zoom ratios, F numbers, etc. are prepared.

[Problem to be solved by the invention]

However, in the conventional example, although there is no problem with the mechanical, electrical, and optical coupling itself between the lens and the camera body, there are the following problems with the aperture and its driving mechanism.

That is, various driving methods (for example, servo motor method, pulse motor method, IG meter method, etc.) are used for the aperture drive mechanism depending on the lens method, F number, zoom ratio, image size, etc. Furthermore, even in the same system, the number of aperture blades, their mass, motor torque, rotation speed, etc. vary. Therefore, the control characteristics of each type are significantly different.

Although it is possible to standardize the DC operating characteristics, it is particularly difficult to standardize parts with different dynamic characteristics, which not only greatly increases costs, but also kills the features of each method. It could become a problem.

Therefore, in the field of video cameras, when replacing a lens, the aperture control characteristics, especially its dynamic characteristics, are manually adjusted on the camera body each time the lens is replaced. It was not easy to change lenses.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a camera device and an interchangeable lens that allow easy lens exchange.

[Means to solve the problem]

A camera device according to the present invention is a camera device with interchangeable lenses, has a memory in the lens that stores identification data for identifying the characteristics of the aperture, and uses the identification data to identify the aperture in the camera body. It is characterized by adjusting control characteristics. The interchangeable lens according to the present invention is characterized by comprising a memory means for storing identification data of aperture characteristics and/or control data corresponding to the aperture characteristics.

[Effect]

On the camera body side, by referring to the memory in the interchangeable lens, the aperture characteristic of each interchangeable lens is known, and the aperture control of the interchangeable lens is changed or adjusted according to the aperture characteristic. Therefore, interchangeable lenses with various characteristics can be used interchangeably with one camera body, and manual adjustment is not required when replacing lenses.

〔Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a block diagram of an embodiment of the present invention. 1
0 is a lens section, and 30 is a camera body.

In the lens unit 10, 12 is a photographing optical system, 14 is an aperture, 16 is a mount, 18 is an electric contact provided on the mount 16, 20 is an aperture drive mechanism, and 22 is data identifying the aperture 14 and the type of the aperture drive mechanism. This is written memory. In the camera body 30, 32 is a mount that is compatible with the mount 16 of the lens unit 10 and is detachable; 34 is a mount that faces the electrical contact 18 of the lens unit 10; 18 is an electrical contact that is electrically connected to the image sensor 36, 38 is a sample and hold (S/H) circuit that samples and holds the output of the image sensor 36, and 40 is a signal processor that processes the output of the S/H circuit 38. 42 is a video output terminal, 44 is a variable gain amplifier, 46 is a variable time constant circuit, and 48 is a microcomputer.

When the mount 16 of the lens 10 is mechanically coupled to the mount 32 of the camera body 30, the electrical contacts 18 are electrically connected to the electrical contacts 34. During this electrical connection, the microcomputer 48 reads the data stored in the memory 22 and controls the gain of the amplifier 44 and the time constant of the variable time constant circuit 46.

The subject image passes through the photographing optical system 12, the amount of light is limited by the diaphragm 14, and then passes through the aperture of the mount 16.32.
The light is incident on the image sensor 36. The image sensor 36 outputs a photoelectric conversion signal, and the S/H circuit 38 extracts a signal component and applies it to the signal processing circuit 40. Signal processing circuit 40 provides a video signal to output terminal 42 . On the other hand, the output of the S/H circuit 38 is first amplified with a predetermined gain by an amplifier 44,
It is applied to the aperture drive mechanism 20 via a variable time constant circuit 46 and electrical contacts 34.18. The aperture drive mechanism 20 controls the aperture of the aperture 14 in accordance with this signal. As described above, the gain of the amplifier 44 and the time constant of the variable time constant circuit 46 are adjusted by the microcomputer 48 to values according to the characteristics of the lens section 10.

FIG. 2 shows a flow chart of the operation of the microcomputer 48. When started (Sl), check whether the power is on or not, and if it is off, wait for it to turn on (S2)
. When the power is on, the data stored in the memory 22 of the lens unit 10 is read out (S3), and it is checked whether the data is appropriate (S4). If appropriate, select data suitable for the attached lens from data previously written in the memory in the microcomputer 48 (S5), and adjust the gain of the amplifier 44 and the variable time constant circuit 4 according to the selected data.
6 is adjusted (S6). After this, move on to other routines. In addition, if the successive data is not appropriate in S4, it is determined that the lens portion 10 is not coupled or the coupling is defective, a warning display of lens abnormality is displayed, and S3
Return to (S8).

Even during other routines, if detachment and/or attachment of the lens unit 10 is detected, the process advances to S3 and the memory 22 of the lens unit 10 is read out preferentially.

FIG. 3 is a block diagram showing an example of the configuration of the amplifier 44 and variable time constant circuit 46. 50°52 is an operational amplifier, 54.56 is a reference voltage, 58°60 is a switch circuit, 62.64, 66.68°70.71 is a resistor, ? 2.
74.76 is a capacitor. Switch circuit 58.6
0 is switched and controlled by the microcomputer 48, and the switch circuit 58 selects one or more of the resistors 64, 66, 68, thereby changing the gain of the amplifier 44, and the switch circuit 60 selects one or more of the resistors 64, 66, 68, and 68. By selecting one or more of 2.74.76, the time constant of the time constant circuit 46 changes.

In the configuration shown in Fig. 3, the gain and time constant are changed discretely by selecting from three elements, but of course it is possible to use other than three elements, and the gain and/or time constant can be changed continuously. It's okay.

In the embodiment shown in FIG. 1, the data stored in the memory 22 of the lens unit 10 is read out by the microcomputer 48 on the camera body side, but the data stored in the memory 22 in the lens unit 10 is read out and transmitted to the camera body 30 side. A circuit element such as a memory control circuit or a microcomputer may be provided to transmit necessary data to the camera body in response to commands from within the camera body.

In transmitting the signal for aperture control from the camera body 30 side to the lens unit 10 side, in the embodiment of FIG. 1, the gain and time constant are adjusted, but other control values, such as error detection gain and phase shift One or more of the characteristics, delay time, maximum control width, unsteady zone width, etc. may be adjusted.

In addition to the method illustrated in FIG. 1, the diaphragm control may also be performed by partial photometry, peak detection, or a soft servo method controlled by a microcomputer.

The data stored in the memory 22 may be a code for identifying the aperture control method, an absolute value or a relative value of a control constant of the aperture control loop, or both, or a plurality of control constants may be stored.

〔Effect of the invention〕

As can be easily understood from the above description, according to the present invention, the camera body side can know the aperture characteristics of each interchangeable lens and change the aperture control of the interchangeable lenses according to the aperture characteristics. Therefore, interchangeable lenses with various characteristics can be used with one camera body and can be replaced quickly.

[Brief explanation of the drawing]

FIG. 1 is a configuration block diagram of an embodiment of the present invention, FIG. 2 is an operation flowchart of the microcomputer 48 in FIG. 1, and FIG. 3 is an amplifier 44 and variable time constant circuit 4 in FIG.
FIG. 6 is a detailed configuration block diagram of FIG. 10- Lens section 30--Camera body 12--Photographing optical system 14--Aperture 16--Mount 18--Electric contact 20--Aperture drive mechanism 22--Memory 32
-Mount 34-・Electrical contact 36- Image element 3
8--Sample and hold circuit 42-Video output terminal 44--Variable gain amplifier 46--Variable time constant circuit 48--Microcomputer diagram diagram diagram diagram diagram

Claims (2)

[Claims] (1) A camera device with interchangeable lenses, which has a memory in the lens that stores identification data for identifying aperture characteristics, and adjusts aperture control characteristics within the camera body based on the identification data. A camera device characterized by: (2) An interchangeable lens characterized by comprising a memory means for storing identification data of aperture characteristics and/or control data corresponding to the aperture characteristics.