KR100219649B1 - Projection lens system optical axis adjusting device - Google Patents

Abstract

A barrel provided with a projection lens for enlarging and projecting an image generated by an image generator embedded in the case to a screen outside the case; A plate member having a housing installed in front of the image generating unit, a lead screw installed in the housing in both side end directions of the screen, and a connecting member supported on the barrel and screwed to the lead screw; Disclosed is a projection lens system optical axis adjusting apparatus of a projector having a rotary knob coupled to an end of a lead screw, and the plate member being reciprocated between both sides of the screen according to the forward and reverse rotation of the rotary knob.

Description

Projection lens system optical axis adjusting device

The present invention relates to a projector for projecting and displaying an image on a screen, and more particularly, to a projection lens system optical axis adjusting apparatus of a projector that can be adjusted so that the optical axis of the projection lens is variable for common use in the rear projection type and the front projection type. will be.

Today, as an apparatus for meeting the demand of reproducing images on a large screen with the development of the information industry, an image projection apparatus using a liquid crystal display device is in the spotlight.

Such an image projecting device is generally composed of a screen and a projector that generates an image on the screen and enlarges the image, and is classified into two types, a rear projection type and a front projection type according to a method of projecting an image on the screen.

The rear-projection image projector is a projector mounted on a cabinet together with a screen so that the image projected from the projector is reflected by a reflector arranged obliquely in the cabinet and projected to the back of the screen. It is installed so that the image projected from the projector is directly projected on the screen to reproduce the image.

On the other hand, recently, a projector that is applicable to both types of front projection type and rear projection type image projection apparatus has been tried and widely used. That is, when the projector of the front projection type is mounted at a predetermined position inside the cabinet provided with the screen and the reflecting mirror, it functions as the rear projection type.

An example of the front projection type as the image projection apparatus is shown in FIG. 1, and as shown, in the front projection type image projection apparatus 1, the projector 10 is a wall 15 such as a theater or a home room, for example. It is provided at a position facing the front of the screen 14 installed in the), so that the image projected from the projector 10 is to appear on the front of the screen (14). The projector 10 has a barrel provided with an image generator 11 built in the case 13 and generating an image, and a plurality of projection lenses 121 for enlarging and projecting the generated image onto the screen 14. It is provided with a (12), and is mounted on a support (not shown) having a predetermined height to project an image on the screen (14).

Here, the image generating unit 11 refers to a plurality of optical members 11b to 11f arranged to generate an image through the light source 11a and the light emitted from the light source 11a, and the optical members 11a to. 11f) includes all of a support (not shown) for supporting the case 13 of the projector. The projection lenses 121 are supported by the barrel 12 at predetermined intervals to receive the image generated by the image generator 11 and to enlarge the projection to the screen 14.

By the way, in the front projection type image projection apparatus 1 as described above, in order to obtain a clear image quality in which the focus is precisely adjusted, the conventional projector 10 uses the center point of the screen 14 ( A ₁ Since the light is projected symmetrically in the horizontal and vertical directions, respectively, to reproduce the image, the projector 10 may be configured in consideration of the fact that the width in the horizontal direction (X direction) of the screen 14 is greater than It can only be located in the center of the viewing space of the user. This is inconvenient in that viewing spaces of users who want to view the image projected on the screen 14 are limited in view of various equipment or wiring relationships for installing the projector 10.

On the other hand, in order to secure the viewing space of the user to install the projector 10 to any side of the screen 14 and then the center point ( A ₁ If it is disposed obliquely toward), the projected image is obliquely incident on the screen 14, the focus is not properly adjusted.

Similarly, when the projector 10 is applied to the rear projection type image projection apparatus, as shown in FIG. 2, light passing through the optical axis of the projection lens 121 is centered on the screen through a reflector (not shown). point( A ₂ Since the projector 10 is generally biased toward one side (right side in FIG. 2) of the cabinet 31 of the rear projection type image projector 3. This is a space in which the other side (the left side in FIG. 2) of the cabinet 31 is left unnecessarily, so that the material for manufacturing the cabinet 31 is not only wasted but also the body of the cabinet 31 is dull and dull. There is a problem that is not desirable.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to provide a projection lens system optical axis adjusting device of a projector capable of adjusting an optical axis of a projection lens to save an installation space of a projector.

1 is a schematic diagram showing a front projection type image projection to which a conventional projector is applied;

2 is a schematic diagram showing a rear projection type image projection device to which a conventional projector is applied;

3 is a schematic perspective view showing an example of a projection lens system optical axis adjusting device of a projector according to the present invention;

4 is a schematic plan view showing the operation of the projection lens system optical axis adjustment device of FIG.

5 is a schematic view showing another example of the projection lens system optical axis adjusting device of the projector according to the present invention;

6 is a schematic diagram of a front projection type image projection apparatus to which the projector of FIG. 3 is applied;

7 is a schematic view of a rear projection type image projection apparatus to which the projector of FIG. 3 is applied.

Explanation of symbols for the main parts of the drawings

21. Housing 22. Body barrel

221. Plate member 221a.Connection member

221b..guide part 222..projection lens

24.42.Screen 25.Lead screw

26. Guide rail 27. Rotating knob

271. Protrusion 28. Compression coil spring

29. Case 291. Knob seat 231a. Insert groove 41. Cabinet

Projection lens system optical axis adjustment apparatus of a projector according to the present invention for achieving the above object, and the barrel provided with a projection lens for projecting the image generated by the image generation unit built in the case to the screen outside the case; And a conveying means for conveying the barrel between both sides of the screen, wherein the conveying means includes a housing installed at the front surface of the image generating unit, a lead screw installed at the housing at both ends of the screen, and the barrel being supported. A plate member having a connection member screwed to the lead screw; Rotating knob coupled to the end of the lead screw; characterized in that the plate member is reciprocally transferred between both sides of the screen according to the forward and reverse rotation of the rotary knob.

Preferably, the plate member is elastically biased in any one direction on both sides of the screen.

The rotary knob is preferably formed to protrude out of the case.

The conveying means is a guide means for guiding the conveyance of the plate member, it is preferable to have a guide rail provided in the housing to be parallel to the lead screw and a guide portion provided in the plate member to be coupled to the guide rail.

Preferably, the plate member has a conveyance distance determined by a positioning means provided in a knob seating portion formed in the case to accommodate the rotary knob and the rotary knob, and an insertion groove formed on an outer circumferential surface of the rotary knob as the positioning means. And, preferably comprises a projection formed on the knob seating portion to be complementary to the insertion groove.

Preferably, the case has an opening formed to allow the barrel to be transferred.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 3, the projection lens system optical axis adjusting device of the projector according to the present invention includes a barrel 22 on which the projection lens 222 is installed, being transported a predetermined distance in the horizontal direction (the X-axis direction) of the screen 24. The optical axis is adapted to be adjusted.

The barrel 22 receives an image generated by an image generator (not shown) built into the case 29 and enlarges and projects the image to the screen 24 through the projection lens 222, and is installed on the front of the image generator. It is supported by the plate member 221 slidably rolled on the housing 21.

A lead screw 25 is installed on one side of the housing 21 to be parallel to the horizontal direction (X-axis direction) of the screen 24, and formed on one side of the plate member 221 on the lead screw 25. The connecting member 221a is screwed in. The rotary knob 27 is coupled to an end of the lead screw 25. The rotary knob 27 is provided to protrude to the outside of the case 29, for example, can be rotated forward and backward by the user's operation. Accordingly, the lead screw 25 is also rotated forward and backward according to the rotation direction of the rotary knob 27 so that the plate member 221 is moved forward and backward between both ends of the screen 24.

In addition, one side of the housing 21 is provided with a guide rail 26 to be parallel to the conveying direction of the plate member 221. It supports the other side opposite to the lead screw 25 has a function of guiding the sliding of the plate member 221. In FIG. 3, reference numeral 221b is provided on both sides of the plate member 211 to show guide parts respectively coupled to the lead screw 25 and the guide rail 26. Reference numeral 292 denotes an opening provided in the case 29 so that the conveyance of the barrel 22 supported by the plate member 211 is guided as the plate member 221 slides.

FIG. 4 is a schematic plan view illustrating the operation of the projection lens system optical axis adjusting apparatus of FIG. 3, and the operation of adjusting the optical axis of the projection lens system will be described with reference to FIGS. 3 and 4.

When the barrel 22 is positioned on one side of the screen 24, that is, the position shown in the solid line in FIG. 4 is to move the optical axis in the other direction (X direction) of the screen 24, the user When the rotary knob 27 is rotated in the counterclockwise direction as seen in FIG. 3, the lead screw 25 also rotates along the rotary knob 27. Since the plate member 221 is screwed to the lead screw 25 through the connecting member 221a, the plate member 221 is guided to the guide rail 26, and the barrel 22 is shown as an imaginary line in FIG. It will be located there. When the user wants to restore the barrel 22 whose optical axis is adjusted as described above to the original position, when the user rotates the rotary knob 27 clockwise when viewed in FIG. 3, the barrel 22 is shown in solid line in FIG. 4. The optical axis of the projection lens 222 is adjusted by feeding in the direction (-X direction).

In the above operation description, the user directly rotates the rotary knob 27, but the rotary knob 27 may be connected to a driving source (not shown) to rotate the rotary knob 27. For example, the rotary knob 27 may be provided as a gear so that the rotary knob 27 may be geared to the output shaft of the driving source, and the user may operate the driving source by externally connecting a switch.

On the other hand, in the projection lens system optical axis adjustment device of the present invention, it is preferable that the plate member 221 is elastically biased in any one direction so that the operation of adjusting the optical axis can be made stable.

The elastic bias means is provided along the lead screw 25 so as to be located between the plate member 221 and the housing 21 as, for example, a compression coil spring 28, the plate member 221 to the screen 24 Elastic bias in one direction of (X direction). Therefore, when the optical axis is adjusted, the barrel 22 supported by the plate member 221 is buffered so that an unstable operation such as shaking is performed. Although not shown in the figure, the compression coil spring 28 is also provided on the guide rail 26.

In addition, it is preferable that the projection lens system optical axis adjusting device of the present invention further includes a positioning means for determining the position of the barrel 22 in the state where the barrel 22 is optically adjusted in either direction at both ends of the screen 24.

As shown in FIG. 5, the positioning means includes a protrusion 271 protruding from an outer circumferential surface of the rotary knob 27 and a knob seat provided on the case 29 of the projector to accommodate the rotary knob 27. An insertion groove 291a is formed in the portion 291 so that the protrusion 271 is inserted into and caught. The insertion groove 291a is provided such that the protrusion 271 is inserted at a position where the optical axis is adjusted so that the transfer of the plate member 221 is completed. Accordingly, as shown in FIG. 5, the transfer distance of the plate member 221 may be determined by one insertion groove 291a, and another insertion groove (not shown) may be further provided. This is sufficient if the screw formed on the lead screw 25 is designed to have a predetermined pitch, which is well known in the art. When the projection 271 is inserted into the insertion groove 291a in the state where the adjustment of the optical axis is completed as described above, reverse rotation of the rotary knob 27 due to external impact is prevented, thereby fixing the position of the barrel 22. This prevents the image projection range from changing while the projector is projecting the image on the screen 24.

Meanwhile, as shown in FIG. 6, an example in which a projector capable of adjusting an optical axis between both ends of the screen 24 is applied to the front projection type image projector as described above. Referring to FIG. 6, unlike the conventional projector 10 illustrated by a solid line located at the center of a viewing space of a user, the projector 20 according to the present invention has an asymmetric image passing through the projection lens 222. While projecting a certain point on either side of the screen 24 ( B ₁ Since the barrel 22 is conveyed so as to be in focus, the projector 20 can be installed at the position shown by the virtual line of FIG. 6. Therefore, the viewing space of the user can be secured more widely.

In addition, when the projector 20 is applied to the rear projection image projecting device 40 as shown in FIG. 7, the image passing through the projection lens 222 is one side of the screen 42, for example, FIG. In the center of the screen (42) A ₂ Left point () B ₂ ) So that the projector 20 can be positioned at the center of the cabinet 41 of the image projection apparatus. Therefore, unnecessary space of the cabinet 41 can be suppressed to a minimum, and the appearance becomes more slender.

As described above, according to the projection lens system optical axis adjusting device of the projector of the present invention, since the optical axis can be adjusted between both ends of the screen, the installation space of the projector can be saved.

Claims (7)

A barrel having a projection lens installed to enlarge and project an image generated by an image generator embedded in a case to a screen outside the case; A conveying means for conveying the barrel between both sides of the screen; The transfer means, A housing installed in front of the image generating unit; A lead screw installed in the housing in both side ends of the screen; A plate member supporting the barrel and having a connection member screwed to the lead screw; A rotary knob coupled to an end of the lead screw; And the plate member is reciprocated between both sides of the screen according to the forward and reverse rotation of the rotary knob. The method of claim 1, And the plate member is elastically biased in one direction on both sides of the screen. The method of claim 1, And the rotary knob is formed to protrude out of the case. The method of claim 1, The transfer means, A guide means for guiding the transfer of the plate member, the projection lens system optical axis of the projector, characterized in that it has a guide rail provided in the housing parallel to the lead screw and the guide portion provided in the plate member to be coupled to the guide rail Adjuster. The method of claim 1, The plate member is a projection lens system optical axis adjusting device of the projector, characterized in that the conveying distance is determined by the positioning means provided in the knob seating portion formed in the case to accommodate the rotary knob and the rotary knob. The method of claim 5, The positioning means, And a projection formed on the knob seating portion to be complementarily coupled to the insertion groove, and an insertion groove formed on an outer circumferential surface of the rotary knob. The method of claim 1, And an opening is formed in the case to allow the barrel to be transferred.

Images