KR20040095816A - Focusing apparatus for viewfinder of camcorder - Google Patents

Abstract

PURPOSE: A device for controlling a view finder focus of a camcorder is provided to enable a lens holder having a lens to smoothly perform a straight line motion along guide shafts by a rotation of an operation dial, thereby precisely controlling a focus of an image created on an LCD plate. CONSTITUTION: A housing(50) is coupled with a view finder body(40) having an LCD plate. An eyecup assembly(60) is coupled with a ton end of the housing(50), and consists of an eyecup(61), one pair of guide shafts(62), and a support(63). A lens assembly(70) is composed of a lens(71) for expanding an image transmitted through a central opening portion(51a) of a shield film(51), and a lens holder(72) for supporting the lens(71). An operation dial(80) straightly moves the lens assembly(70) along the guide shafts(62), to control a focus of an image transmitted through a window(61a) of the eyecup(61).

Description

Viewfinder focusing device for camcorders {FOCUSING APPARATUS FOR VIEWFINDER OF CAMCORDER}

The present invention relates to a viewfinder of a camcorder, and more particularly, to a viewfinder focusing apparatus of a camcorder capable of freely adjusting focus by moving a lens.

In general, a camcorder is a device capable of recording an image of a subject to be shot on a recording tape and playing back the recorded image. A viewfinder used in the camcorder is played back from an image or tape captured by a camera. It serves as a monitor that allows the user to see the image directly with the naked eye. Such a viewfinder can be classified into an electric view finder (EVF) using a cathode ray tube (CRT) and a color view finder (CVF) using a liquid crystal panel (LCD). Is in the trend of becoming.

FIG. 1 is a schematic view showing a viewfinder of a conventional camcorder. As shown in FIG. 1, the viewfinder is connected to the viewfinder body 10 and the body 10 that are movably connected to the camcorder body. It is provided with a lens guide housing 20 to be moved in the housing 20, the lens holder 31 and the focus adjusting means for adjusting the focus by moving the lens holder 31 and the lens holder 31 for supporting the lens 30 do.

The body 10 includes a liquid crystal display panel 11 and is installed to be slidable or rotatable with respect to the camcorder body. The housing 20 is coupled to one side of the body 10, and the eye cup 21 of rubber material is coupled to the front end of the housing 20. The lens holder 31 supporting the lens 30 is installed to be able to move forward and backward along the guide rail 22 provided in the housing 20. The focus adjusting means for moving the lens holder 31 includes a cam guide part 31a provided to be inclined at a predetermined angle in a forward and backward direction to the bottom surface of the lens holder 31 and the lower surface of the housing 20. It includes an operating member 32 is inserted into the slit (20a) formed to be connected to the cam guide portion (31a).

The operating member 32 slides in a direction orthogonal to the forward and backward directions of the lens holder 31 along the slit 20a of the housing 20 while interlocking the cam guide portion 31a to guide the lens holder 31. To move forward and backward along the rail (22). When the user views an image displayed on the liquid crystal panel 11 through the eye cup 21, the user moves the lens holder 31 using the operation member 32 to adjust the focus so that the image can be clearly seen.

However, according to the above configuration, since each of the components are all made of a molded object, the operation feeling may vary depending on the injection conditions during mass production, and if foreign matters due to the friction during operation, it is difficult to precisely adjust the focus do.

In addition, since the slit 20a for sliding the operation member 32 is open to the outside, foreign matter may flow into the viewfinder through the slit 20a.

The present invention has been made in view of the above problems, the movement of the lens for the focus adjustment can be made smoothly and precisely, the camcorder is improved in structure to prevent the inflow of foreign matter such as dust therein Its purpose is to provide a viewfinder focusing device.

1 is a view schematically showing a viewfinder for a conventional camcorder,

2 is an exploded perspective view showing the configuration of a viewfinder focusing apparatus for a camcorder according to a preferred embodiment of the present invention;

3 is a perspective view showing the main part of the camcorder viewfinder focusing device shown in FIG. 2;

4 is a view for explaining the operation of the viewfinder focusing apparatus for a camcorder according to a preferred embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

50; housing 51; barrier

60; eye cup assembly 61; eye cup

62; guide shaft 63; support

70; lens assembly 71; lens

72; lens holder 80; operation dial

81; dial body 82; rotary shaft

83; camera

Viewfinder focusing apparatus of the camcorder according to the present invention for achieving the above object, the housing is connected to the viewfinder body; An eye cup assembly coupled to the front end of the housing and having a guide shaft; A lens assembly installed in the housing and installed to be movable by a predetermined distance along the guide shaft; And a working dial rotatably installed in the housing to move the lens assembly.

According to this, when adjusting the lens focus, the user can linearly move the lens by turning the operation dial projecting out of the housing, so that the movement of the lens and the focus adjustment of the lens can be made smoothly and precisely.

Here, the lens assembly has a long groove on one side thereof, the operation dial is provided with a cam protrusion inserted into the long groove, the cam assembly is moved along the long groove when the operation dial is rotated the lens assembly It is good to interlock.

In addition, a shaft groove is formed in the housing, and the operation dial may have a rotation center shaft inserted into the shaft groove.

In addition, one side of the housing is formed with a slit for communicating the inside and the outside of the housing, the operating dial is preferably installed so that a portion of the protruding out through the slit.

In addition, the position of the line connecting the cam projection and the rotation center axis is perpendicular to the guide shaft as a reference position, it is preferable that the angle of rotation of the operation dial in the forward and reverse directions about the reference position.

In addition, when the moving distance of the lens assembly is set to D, the length L of the long groove is preferably at least 1/2 of the length A of the entire movement trajectory drawn by the cam projection by the rotation of the operating dial.

In addition, the outer periphery of the operation dial may be provided with an uneven portion for smooth user operation.

Hereinafter, a viewfinder focusing apparatus of a camcorder according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

Figure 2 is an exploded perspective view showing the configuration of the viewfinder focusing apparatus of the camcorder according to a preferred embodiment of the present invention, Figure 3 is a perspective view showing the main part of the viewfinder focusing apparatus of the camcorder shown in Figure 2, Figure 4 Is a view for explaining the operation of the viewfinder focusing apparatus of the camcorder according to the preferred embodiment of the present invention.

2 and 3, the viewfinder focusing apparatus of the camcorder according to the present invention includes a housing 50, an eye cup assembly 60, a lens assembly 70, and an operation dial 80. ).

The housing 50 is coupled to the viewfinder body 40 in which the liquid crystal panel 11 (see FIG. 1) is installed, and has a rectangular duct shape. The housing 50 is provided with a blocking film 51 having both ends open and a central part thereof opened therein. The image generated from the liquid crystal panel 11 of the viewfinder body 40 is transferred to the lens assembly 70 through the center opening 51a of the shielding film 51. The shielding film 51 is formed with a coupling hole 51b to which the guide shaft 62 to be described later is coupled. In addition, the inner bottom surface of the housing 50 is formed with a shaft groove (50a) for rotatably supporting the operation dial 80, one side of the housing 50 protrudes the operation dial 80 to the outside of the housing 50 The slit 50b is formed.

The eye cup assembly 60 is coupled to the front end of the housing 50, and a pair of guide shafts 62 integrally formed by insert molding molded into the eye cup 61 and the eye cup 61. ) And support beam (63). The central portion of the eye cup 61 is formed with a window 61a for checking an image transmitted through the central opening 51a of the chakmak 51 and the lens assembly 70. The guide shaft 62 is for guiding the linear movement of the lens assembly 70. Since the surface of the guide shaft 62 is made of a smooth metal material, the guide shaft 62 has a low friction with the eye cup assembly 60 so that the eye cup assembly 60 can be smoothly moved. Induce to help. One end of the guide shaft 62 is inserted into the coupling hole 51b. The support beam 63 is in contact with one side of the housing 50 when the eye cup assembly 60 and the housing 50 are coupled to prevent the eye cup assembly 60 from being separated from the housing 50.

The lens assembly 70 includes a lens 71 for enlarging an image transmitted through the central opening 51a of the shielding film 51 and a lens holder 72 for supporting the lens 71. do. A coupling portion 72a for accommodating the lens 71 is formed in a central portion of the lens holder 72 to approximately the size of the lens 71, and the guide shaft 62 is inserted into both lower sides of the coupling portion 72a. Guide holes 72b are formed. The lens holder 72 is installed inside the housing 50 such that the guide shaft 62 is inserted into the guide hole 72b so as to linearly move along the guide shaft 62 in the housing 50 by a predetermined distance. 3, a long groove 72c having a predetermined size into which the cam protrusion 83 of the operation dial 80 to be described later is inserted is formed below the lens holder 72. The length of the long groove 72c is an element that determines the moving distance of the lens assembly 70, and its value is determined according to the moving distance of the lens assembly 70. As shown in FIG. 4, when the moving distance of the lens assembly 70 is D, the length L of the long groove 72c is the length of the entire rotational trajectory drawn by the cam protrusion 83 by the rotation of the operation dial 80. It should be at least 1/2 of A.

The operation dial 80 is for adjusting the focus of the image transmitted through the window 61a of the eye cup 61 by moving the lens assembly 70 along the guide shaft 62 in a straight line. 81, a central rotation shaft 82 provided at the lower center of the dial body 81, and a cam protrusion 83 provided to be eccentric to the upper one side of the dial body 81. The operation dial 80 is formed inside the housing 50 such that the rotation angles of the center rotation shaft 82 and the cam protrusion 83 in the forward and reverse directions with respect to the position perpendicular to the guide shaft 62 are the same. Is installed. That is, as shown in FIG. 4, the operation dial 80 rotates the lens assembly 70 by a predetermined angle in a forward direction (clockwise) at a position C that is half of the moving distance D of the lens assembly 70. The lens assembly 70 is moved by D / 2 by moving by D / 2 and rotating the same angle in the reverse direction (counterclockwise) at the position of C. The distance r from the central rotation shaft 82 to the cam protrusion 83 is an element that affects the operation sensitivity for rotating the operation dial 80. If the distance r is large, the lens assembly by the rotation of the operation dial 80 is large. The movement distance of the 70 is increased, but the force for the operation is increased. On the contrary, when the distance r is small, the force for operation is low, but the moving distance of the lens assembly 70 due to the rotation of the operation dial 80 is reduced. Therefore, the size of the distance r is set to an appropriate size when the moving distance of the lens assembly 70 is determined. In addition, an uneven portion 81a is formed around the outer circumference of the dial body 81 for a user operation. This uneven portion 81a helps the user to smoothly turn the dial body 81 without slipping. When the operation dial 80 is installed inside the housing 50 such that its center rotation shaft 82 is inserted into the shaft groove 50a of the housing 50, the cam protrusion 83 of the operation dial 80 is a lens holder ( It is inserted into the long groove 72c of 72 and a part of the operation dial 80 protrudes out through the slit 50b of the housing 50.

Hereinafter, the operation of the viewfinder focusing apparatus of the camcorder according to the present invention will be described with reference to FIG. 4.

The user checks the image transmitted from the liquid crystal panel 11 (see FIG. 1) provided in the viewfinder body 40 (see FIG. 2) through the window 61a of the eye cup 61. At this time, if the image transmitted through the window 61a is not in focus, the user rotates the operation dial 80 protruding out of the housing 50 in the forward or reverse direction. Then, the operation dial 80 is rotated about the center rotation axis 82 and the cam projection 83 is moved along the long groove 72c of the lens holder 72 to interlock the lens holder 72. In this case, the lens holder 72 changes the focus of the image transmitted through the window 61a while linearly moving in the forward / reverse direction along the guide shaft 62. Here, the movement distance D of the lens holder 72 is limited by the cam projection 83 of the operation dial 80 contacting the end of the long groove 72c of the lens holder 72.

As such, by rotating the operation dial 80, the lens holder 72 is smoothly linearly moved along the guide shaft 62, thereby accurately adjusting the focus of the image generated from the liquid crystal display panel 11.

On the other hand, in the above description, the lens holder 72 in which the lens 71 is installed is linearly moved by the operation dial 80. However, the lens 71 does not include the lens holder 72, and the lens 71 directly guides the shaft. 62 may be movably installed. In this case, the lens 71 has a long groove into which the cam protrusion 83 is inserted and a guide groove into which the guide shaft 62 is inserted, and has a shape similar to that of the lens holder 72.

According to the viewfinder focusing apparatus of the camcorder of the present invention as described above, the lens holder provided with the lens is smoothly linearly moved along the guide shaft by the rotation of the operation dial. Therefore, it is possible to precisely adjust the focus on the image generated from the liquid crystal panel.

Further, according to the present invention, since the operating dial is installed to block the slit communicating the inside and the outside of the viewfinder, foreign matter such as dust is introduced into the viewfinder through the opening such as the slit as in the prior art. You can prevent it.

While the invention has been shown and described with respect to preferred embodiments for illustrating the principles of the invention, the invention is not limited to the construction and operation as shown and described. Rather, those skilled in the art will appreciate that many modifications and variations of the present invention are possible without departing from the spirit and scope of the appended claims. Accordingly, all such suitable changes and modifications and equivalents should be considered to be within the scope of the present invention.

Claims (7)

A housing connected to the viewfinder body; An eye cup assembly coupled to the front end of the housing and having a guide shaft; A lens assembly installed in the housing and installed to be movable by a predetermined distance along the guide shaft; And a working dial rotatably installed in the housing to move the lens assembly. The method of claim 1, The lens assembly has a long groove on one side thereof, the operation dial is provided with a cam protrusion inserted into the long groove, the cam projection is moved along the long groove when the operation dial is rotated to interlock the lens assembly. The viewfinder focusing apparatus of the camcorder. The method of claim 2, A shaft groove is formed in the housing, and the operation dial has a viewfinder focusing apparatus of the camcorder, characterized in that it has a rotational central shaft inserted into the shaft groove. The method according to claim 1 or 3, One side of the housing is formed with a slit communicating the inside and the outside of the housing, the operation dial is a viewfinder focusing apparatus of the camcorder, characterized in that a part of which protrudes out through the slit. The method of claim 3, wherein The operation dial is rotated in the forward and reverse directions about the reference position with the same position that the line connecting the cam projection and the rotation center axis is perpendicular to the guide shaft. Viewfinder focusing device. The method of claim 5, wherein When the moving distance of the lens assembly is set to D, the length L of the long groove is 1/2 or more of the length A of the entire movement trajectory drawn by the cam protrusion by the rotation of the operating dial. Focusing device. The method of claim 1, Viewfinder focusing apparatus of the camcorder, characterized in that the irregularities for smooth user operation is provided around the outer circumference of the operation dial.