JPH04281434A - converter - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a converter for connecting different types of lens barrels and camera bodies.

0002

2. Description of the Related Art In recent years, due to the development of actuators, sensors, electronic circuits, etc., autofocus and automatic exposure control have become mainstream for both video cameras and still cameras.

For single-lens reflex still cameras, there are known interchangeable lenses that mechanically control the aperture and drive the focusing lens from the camera body, as shown in Japanese Patent Publications No. 63-67171 and No. 63-67172. .

On the other hand, as an aperture and lens drive system for an interchangeable lens single-lens reflex camera, a proposal has been made that eliminates the mechanical interlocking between the camera body and lens barrel, and adopts a system in which the lens and aperture are driven only by electrical connection. The present applicant has already filed an application (for example, Japanese Patent Publication No. 1-17139). This system uses a dedicated actuator for each lens, so it has many advantages such as focusing speed, accuracy, and silence.

[0005] Furthermore, as compact video cameras become more popular, there is a growing need for video cameras with interchangeable lenses. Even in a video camera with interchangeable lenses, a system having only the latter electrical connection and having a dedicated actuator for each lens is desirable.

[0006]

[Problem to be solved by the invention] There is a strong need to use many manual interchangeable lenses on the market for the above-mentioned camera body, but the mount shape of the mounting part is different, or the lens to which the camera body is attached. The problem was that it did not work because it could not be checked electrically.

[0007]

[Means for Solving the Problems] The present invention provides a converter with communication means for communicating with a camera body, and a specific type of lens barrel (for example, a lens barrel dedicated to manual focus).
Since the communication means is used to transmit a signal to the camera body to recognize that the camera is attached, it is now possible to take pictures even when using different types of lens barrels.

[0008]

[Embodiment] Fig. 1 is a sectional view of a converter as an embodiment, Fig. 2 is a perspective view thereof, Fig. 3 is a configuration diagram of a camera system with the converter of Fig. 1 installed, and Fig. 4 is a signal flow. FIG.

Reference numeral 1 designates a first bayonet mount having a claw portion 1a that can be attached to a mount of a video camera 13, which will be described later. Reference numeral 2 denotes a main body, which has a second bayonet mount that can be attached to a lens barrel 11, which will be described later. Reference numeral 3 denotes an internal fixing part in which a plurality of contacts 4 are insert-molded. 5a
, 5b is a circuit board, and 6 and 6' are c having memory means.
This is a circuit element including pu20. Note that the CPU 20 stores information indicating a manual type lens.

FIG. 3 shows the video camera 13 and lens barrel 11 mounted with the converter 12 shown in FIG. It is a manual type that can only be done. 31 is a focus operation ring; 32 is a holding lens barrel holding a focusing lens I;
It has a gear 32a that meshes with the gear 31a. When the focus operation ring 31 is rotated, the holding lens barrel section 32 is moved in the optical axis direction by gear coupling, and the focusing lens I can perform focusing. 33 is an aperture operation ring, 34 is a transmission member that transmits the rotation of the operation ring, and 35 is an aperture device. When the aperture operation ring 33 is rotated, the transmission member 34 is linked to drive the aperture device 35, and the aperture opening can be varied.

In the video camera 13, reference numeral 15 is a contact point that comes into contact with the contact point of the converter 12, and when a lens barrel (not shown) of a type suitable for this video camera 13 is directly attached, the contact point of the lens barrel come into contact with. Reference numeral 16 denotes a CCD, which receives subject light and forms a video signal, and also serves to detect a focus state and perform photometry. Reference numeral 17 denotes a CPU within the camera, which receives the output (focus, photometry) of the CCD 16, performs calculations, and outputs aperture control information and focus control information via a contact point 15. In addition, c
When the power is turned on, the PU 17 outputs a signal 22 (described later) through the contact 15 to confirm the type of lens attached. It is designed to determine the type of

FIG. 4 is an explanatory diagram showing communication between the CPU 20 and the CPU 17. When a signal 22 for confirming the lens type is supplied from the CPU 17, the CPU 20 transmits a signal 23 indicating a manual type lens barrel to the CPU 17.
supply for. Thereby, the video camera 13 performs the operation when a manual type lens barrel is attached. If no signal is returned in response to the signal 22 supplied from the CPU 17, the video camera 13 determines that the lens barrel is not attached or that an inappropriate lens barrel is attached. This will cause it to stop working.

Although the lens barrel 11 used in the embodiment is not suitable, by attaching the converter 12, it is recognized as a proper manual type lens barrel, and the video camera 13 does not take a picture. It will be.

FIG. 5 shows a second embodiment, in which the lens type of the video camera is determined not by communication between CPUs but by a logic circuit. The converter 12 is provided with a signal generation circuit 36, and the video camera 13 is provided with a signal reception circuit 37. The signal generation circuit 36 sends binary signals 31a to 31c to the signal reception circuit 37 by turning ON and OFF an electric encoder (brush, etc.) or an electric contact, and creates a preset signal so that the video camera 13 make it work.

FIG. 6 shows a third embodiment in which a signal 4 is output from a circuit 47 of a video camera 13 in synchronization with a clock signal 41.
2 is sent to circuit 46 of converter 12, and signal 42 is sent through short circuit 44 as signal 43 to circuit 47. In this case, when the signals 42 and 43 are equal, the same effect as in the first embodiment can be obtained by storing in the circuit 47 that it is the manual type lens barrel 11 used in this case.

Although the signal transmission means described above is electrical, it is easily possible to use a method of converting optical communication or mechanical movement into an electrical signal.

Although the camera body in the above embodiment has been explained by taking a video camera as an example, it goes without saying that the same implementation can be carried out with a still video camera or a still camera for silver halide.

[0018]

[Effects of the Invention] Since the converter of the present invention recognizes that a specific type of lens barrel is attached to the camera body, it is possible to take pictures using a lens barrel of a different type that cannot be used originally. can.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a converter as an example.

[Figure 2] Perspective view of the converter in Figure 1

[Figure 3] Configuration diagram of a camera system using the converter in Figure 1

FIG. 4 is an explanatory diagram showing the flow of signals in the first embodiment.

[Figure 5
]Explanatory diagram of the second embodiment

[Fig. 6] Explanatory diagram of the third embodiment

[Explanation of symbols]

1 First bayonet mount 2a 2nd bayonet mount 4, 15 Contact 17, 20 cpu 11 Lens barrel 12 Converter 13 Video lens

Claims (1)

[Claims] 1. A converter installed between a camera body and a lens barrel, comprising: communication means for communicating with the camera body; A converter comprising: a signal output means for outputting a signal for recognizing that a lens barrel is attached.