JPH04234718A - Lens-barrel - Google Patents

Abstract

PURPOSE:To prevent image from jiggling at the time of automatic focusing, to make the stopping noise small, as well, and to prevent the deterioration of an image at the time of manual focusing by making the position of a stopper different at the time of automatic focusing and the manual focusing. CONSTITUTION:At the time of automatic focusing of search mode, the stopping of lens barrel 1 is begun at the dislance l before L of infinite position L by projection 20 provided on the stopper 20. The projection 20 is formed with an elastic member such as rubber. At the time of a manual operation, rotational force is obtained by a hand, and is greater than that of automatic focusing, so the projection 20 is deformed and stopped at the distance L.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention provides at least a fixed cylinder;
The present invention relates to a lens that includes a focusing lens barrel that moves in the axial direction with respect to the fixed barrel, and has a stopper that restricts the focusing lens barrel from moving toward infinity.

0002

2. Description of the Related Art A lens barrel consisting of a fixed barrel having a helicoid and a focusing lens barrel that is rotatably provided with respect to the fixed barrel is described in the following literature.
It is conventionally well known. Such a lens barrel is provided with a stopper in order to restrict the amount of movement of the focusing lens barrel in the axial direction or rotational direction. That is, as shown in FIG. 4, the fixed barrel 2 is provided with a stopper 7, and the infinity side is spaced from the focusing lens barrel 1 by an L dimension.
It is set to super infinity.

0003

A large L dimension as described above has an advantage during automatic focusing, but causes problems during manual focusing. That is, during automatic focusing, the focusing lens barrel 1 is driven by the motor, but at that time, the motor is stopped by the detection sensor at the infinite position. However, in a so-called search mode that shortens the time from large blur to focus in order to speed up automatic focusing, even if the sensor detects an infinite position and stops the motor, the focusing lens barrel 1 rotates due to inertia. However, if the L dimension is large, there is an advantage that the image will not hit the stopper 2 and cause image distortion, and the sound of the collision with the stopper will not be picked up by the microphone.

However, when focusing manually, there is a drawback that when the lens is driven to the stopper 7 position and an infinite object is viewed, the amount of blur increases because the L dimension is large. SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a lens barrel that does not cause image wobbling during automatic focusing, does not pick up stopper noise, and does not cause large blur during manual focusing.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the present invention includes at least a fixed barrel, a focusing lens barrel that moves in the axial direction with respect to the fixed barrel, and a focusing lens barrel that moves in the axial direction with respect to the fixed barrel. In a lens in which the lens barrel has a stopper that restricts movement toward infinity, the position of the stopper is configured to be different between manual operation and automatic operation. Further, the invention according to claim 2 includes at least a fixed barrel and a focusing lens barrel that moves in the axial direction with respect to the fixed barrel, and the focusing lens barrel has a stopper that restricts movement toward infinity. In this lens, a deformable convex portion is formed in a part of the stopper so that the position of the stopper is different between manual operation and automatic operation.

[0006]

As described above, according to the present invention, the position of the stopper that restricts the movement of the focusing lens barrel is different between manual operation and automatic operation, so there is no impact from the stopper during automatic focusing. Also, the amount of blur does not increase when manually focusing.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In carrying out the present invention, the stopper may be configured to be movable, for example, by a motor, and the superinfinite amount may be increased during automatic focusing and reduced during manual focusing. However, in the following embodiments, only embodiments in which the stopper is provided with a deformable convex portion are shown.

One embodiment of the present invention will be described below. Figure 1
3 shows an embodiment of the present invention, and in FIG. 1, 1 is a focusing lens barrel, 2 is a fixed barrel having a helicoid, 3 is a zoom ring, 4 is a relay barrel, 5 is a focusing lens, 9 is a drive motor, 6 in Fig. 2 is a stopper rubber, 7 is a brush,
8 indicates an encoder flexible plate. During automatic focusing, the focusing lens 5 is rotated by a drive motor 9 and moved back and forth by a helicoid in a fixed barrel. At that time, the infinite position is detected by the brush 7 and the encoder flexible plate 8, and the motor is stopped. At that time, the motor speed is extremely slow near the focus, so there is no inertia and the motor stops almost at the encoder position.

However, in the so-called search mode, which shortens the time from large blur to focus in order to increase the automatic focusing speed, even if the infinite position is detected by the encoder and the motor is stopped, the lens will rotate due to inertia. Further, in recent years, focusing lenses have become smaller and their sensitivity has increased, and there is a tendency to reduce the superinfinite dimension L. The so-called manual stopper position L dimension position is set so that the infinite subject will not be blurred.

Therefore, in this embodiment, as shown in FIG. 3, a partially protruding convex portion 20 is added to change the stop position in so-called search mode during automatic focusing from infinity to the L dimension. In addition, during manual operation, since the rotational force is large by hand, the convex portion is crushed and stops at the L dimension. The so-called convex portion 20 is formed of an elastic member such as rubber.

[0011]

[Effects of the Invention] As described above, according to the present invention, since the position of the stopper is different between automatic focusing and manual focusing,
There is no image wobbling during automatic focusing, and the stopper noise is small. Furthermore, there are many effects such as improved image performance during manual focusing.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the present invention.

FIG. 2 is an enlarged sectional view of the main part shown in FIG. 1.

FIG. 3 is an enlarged view of the stopper part.

FIG. 4 is an enlarged sectional view of a conventional stopper section.

[Explanation of symbols]

1...Focusing lens barrel 2...Fixed cylinder 6...Stopper 20...Protrusion

Claims (2)

[Claims] 1. A lens comprising at least a fixed barrel and a focusing lens barrel that moves in the axial direction with respect to the fixed barrel, the focusing lens barrel having a stopper that restricts movement toward infinity, A lens barrel characterized in that the position of the stopper differs between when the stopper is operated manually and when it is automatically operated. 2. A lens comprising at least a fixed barrel and a focusing lens barrel that moves in the axial direction with respect to the fixed barrel, the focusing lens barrel having a stopper that restricts movement toward infinity, A lens barrel characterized in that a deformable convex portion is formed in a part of the stopper so that the position of the stopper is different between manual operation and automatic operation.