KR100466104B1 - LCD Projector and Keystone Correction System Used in It - Google Patents

Abstract

The present invention relates to an LCD projector and a keystone correction system used therefor that can adjust the direction of a projection lens and at the same time correct keystones generated when the projection direction is adjusted, the image display means being formed by the image display means. An LCD and a projection lens for sequentially passing light, a first housing for fixing and supporting the image display means and the LCD, and a second housing rotatably holding the projection lens and connected to the first housing. An LCD projector comprising:

The second housing is formed in a "-shape" shape to fix and support the projection lens at its end, and therein the first reflection mirror for changing the path of the light passing through the LCD to the projection lens, and the second housing A second reflecting mirror which changes the path of the light passing through the LCD to the first reflecting mirror when it is rotated to have an angle of 90 ° with respect to the first housing, and passes through the LCD when the second housing is turned; A cover which is opened so as not to block a path of light and which closes the space between the first housing and the second housing when the second housing is not rotated, and the keystone correction system comprises A change amount detecting means for detecting an angular change, a control portion for determining a keystone correction amount, and an image display correction portion for controlling the image display means to output a video signal corrected with keystones; Include.

Description

LCD Projectors and their Keystone Correction Systems

The present invention relates to an LCD projector and a keystone correction system used therefor. More particularly, the present invention relates to an LCD projector and a keystone correction system used to adjust the orientation of the projection lens and to correct keystones generated when the orientation is adjusted. will be.

Recently, as a home image display device, a need for a display device capable of high definition and large screens has been on the rise to improve user's viewing feeling. In particular, research on a projection display device for a large screen is continuing. There are two types of projection display devices using LCDs, a front projection type and a rear projection type.

In the case of the front projection type, the screen size can be varied, so it is mainly used for a large screen of 100 inches or more. However, there is a problem in that contrast is very sensitive to ambient brightness. In addition, the set is fixed to the table, so that the projection lens always watches the screen with a constant projection angle, and in order to change the projection angle, it is inconvenient to use because the direction of the projection lens must be changed by opening the set. .

In addition, the LCD projector of the prior art as described above has a problem that the set is fixed in one direction and occupies a lot of space, so that it cannot be applied to various installation environments such as wall-mounting.

The present invention has been made to solve the problems of the prior art as described above, the object is to be configured to rotate a part of the housing to adjust the direction of the projection lens according to the installation environment can be easily changed the projection direction To provide an LCD projector.

In addition, another object of the present invention is to provide a keystone correction system for an LCD projector that can automatically correct the keystone generated when the projection direction is adjusted by detecting the projection angle of the LCD projector.

The present invention for achieving the above object is an image display means, an LCD and a projection lens for sequentially passing the light formed in the image display means, a first housing for fixing and holding the image display means and the LCD, An LCD projector comprising a second housing fixed to support the projection lens but rotatable based on a connection with the first housing.

The second housing is formed in a "-shape" shape to fix and support the projection lens at its end, and therein the first reflection mirror for changing the path of the light passing through the LCD to the projection lens, and the second housing A second reflecting mirror which changes the path of the light passing through the LCD to the first reflecting mirror when it is rotated to have an angle of 90 ° with respect to the first housing, and passes through the LCD when the second housing is turned; It is open so as not to block a path of light, and when the second housing is not rotated, it characterized in that it comprises a cover for closing the space between the first housing and the second housing.

According to an embodiment of the present invention, when the second housing is rotated to have an angle of 90 ° with respect to the first housing includes a second reflecting mirror for changing the path of the light passing through the LCD to the first reflecting mirror can do. In addition, the second housing is opened so as not to block the path of the light passing through the LCD when the second housing is rotated, and between the first housing and the second housing when the second housing is not rotated. It is preferable to include a cover to close the space.

On the other hand, the present invention for achieving the other object, the image display means, the LCD and the projection lens for sequentially passing the light formed in the image display means, and the first housing for holding and holding the image display means and the LCD and And a second housing fixed to support the projection lens but rotatable based on a connection portion with the first housing, wherein the second housing is formed in a L shape to fix and support the projection lens at an end thereof. And a first reflecting mirror for changing the path of the light passing through the LCD to the projection lens, and the path of the light passing through the LCD when the second housing is rotated to have an angle of 90 ° with respect to the first housing. An LCD projector comprising a second reflecting mirror for changing a light into the first reflecting mirror,

Change amount detecting means for detecting the change in the angle of the second reflection mirror to determine the amount, a control unit for determining and controlling the keystone correction amount in accordance with the output value of the change amount detecting means, and the keystone in accordance with the control signal of the control unit A keystone correction system for an LCD projector including an image display correction unit for controlling the image display means to output a corrected image signal.

According to an embodiment of the present invention, the change amount detecting means converts a rack gear mounted on one end of the second reflection mirror, a pinion gear meshing with the rack gear, and a rotation amount of the pinion gear into an electrical signal. It consists of a signal conversion unit. The control unit may include: a signal input unit for receiving and converting an NTSC video signal or an R, G, B, H, and V signal of a PC from outside, and a memory for receiving an output signal of the signal input unit and storing signal values for each pixel; And a keystone correction unit for determining a keystone correction value according to the output signal of the change amount detecting unit, a memory controller for controlling the output of the memory according to the output signal of the keystone correction unit, and the memory and image display correction unit. A panel interface coupled between the timing controller for synchronizing the memory controller and the panel interface, and a microcomputer for controlling the signal input unit, the memory controller and the timing controller.

Hereinafter, exemplary embodiments of an LCD projector and a keystone correction system used therein will be described in detail with reference to the accompanying drawings.

Brief Description of Drawings Fig. 1 is a diagram showing a configuration in the case of using the present invention for wall mounting, and Fig. 2 is a diagram showing a configuration in the case of using the invention for a table.

1 and 2, when the present invention is used for wall-mounting, the LCD 120 and the projection lens sequentially passing the image display means 110 and the light formed by the image display means 110. 130, the first housing 140 fixedly supporting the image display means 110 and the LCD 120, and the projection lens 130 is fixed to an end thereof, and a connection portion between the first housing 140 is fixed. And a second housing 150 which is rotatable as a reference and is formed in an L-shape. The first reflective mirror 160 is fixed to the inside of the second housing 150 to change the path of the light passing through the LCD 120 to the projection lens 130.

Referring to FIG. 2, when the second housing 150 is rotated to have an angle of 90 ° with respect to the first housing 140 in order to use the present invention for a table, the LCD 120 passes through the LCD 120. And a second reflecting mirror 170 for changing the path of the light to the first reflecting mirror 160.

In addition, when the second housing 150 is rotated, the second housing 150 is opened so as not to block a path of the light passing through the LCD 120, and the second housing 150 is not rotated. In this case, the cover 180 may be configured to close the space between the first housing 140 and the second housing 150.

The LCD projector of the present invention having the configuration as described above can be selected and used for the table and the wall-mounted, but when used for the wall-mounted to remove the second reflecting mirror 170 is used. At this time, the cover 180 is closed to prevent dust or foreign matter from entering the system.

In addition, the image passing through the LCD 120 proceeds to the projection lens 130 via the first reflecting mirror 160 and the second reflecting mirror 170, as shown in FIG. By adjusting the angle between the first reflection mirror 160 and the second reflection mirror 170 with the horizontal plane, the projection direction is adjusted by changing the direction of the output beam.

If the direction of the beam is changed, there is a problem that a keystone occurs as shown in FIG. 4. Therefore, the present invention includes a circuit for correcting the above keystone.

Meanwhile, the keystone correction system for the LCD projector for correcting the keystone generated as described above will be described in detail with reference to the accompanying drawings.

5 is a block diagram showing the configuration of a keystone correction system according to the present invention.

Referring to FIG. 5, the keystone correction system for an LCD projector according to the present invention includes a change amount detecting unit 210 for detecting an angle change of the second reflection mirror 170 of FIG. 2 and determining the amount thereof, and the change. A control unit 220 for controlling the system by determining a keystone correction amount according to the output value of the amount detecting means 210, and the image display means for outputting an image signal whose keystone is corrected according to the control signal of the control unit 220 (Fig. And an image display correction unit 230 for controlling 110 of 1.

As shown in FIG. 2, the change amount detecting unit 210 fits into an arc-type rack gear 211 mounted at one end of the second reflection mirror 170 and the rack gear 211. Physics consists of a pinion gear 212 and a signal converter 213 for converting the amount of rotation of the pinion gear 212 into an electrical signal.

In addition, the controller 220 receives an NTSC video signal or an R, G, B, H, V signal from a PC and converts the signal input unit 221 and the output signal from the signal input unit 221. A memory 222 for storing a signal value for each pixel, a keystone correction unit 223 for determining a keystone correction value according to the output signal of the change amount detecting unit 210, and an output of the keystone correction unit 223 A memory controller 224 controlling an output of the memory 222 according to a signal, a panel interface 225 connected between the memory 222 and an image display correcting unit 223, and the memory controller 224. And a timing controller 226 for synchronizing the synchronization of the panel interface 225, and a microcomputer 227 for controlling the signal input unit 221, the memory controller 224, and the timing controller 226.

Referring to the operation of the keystone correction system in the present invention described above is as follows.

First, when the user changes the angle of the second reflecting mirror (170 in FIG. 2) to change the projection direction, the rack gear 211 of the change amount detecting means 210 moves and accordingly the pinion gear ( 212 rotates. The signal conversion unit 213 converts the rotation amount of the pinion gear 212 into an electrical signal and inputs it to the control unit 220.

Thereafter, the controller 220 receives an external NTSC video signal or an R, G, B, H, V signal of a PC from the signal input unit 221 and stores a signal value for each pixel in the memory 222. At this time, the keystone correction unit 223 determines the keystone correction value according to the output signal of the change amount detecting unit 210 and controls the output of the memory 222. The keystone correcting unit 223 calculates a keystone amount according to the projection direction in advance, and compares the keystone correction value with the signal input from the signal converting unit 213. When the keystone is generated, a change amount of dy / dx is generated as shown in FIG. 4, and a change amount of x1 and x2 is shown on the left and right sides in the line X. The change amount is calculated for each line using the amount of keystone as described above. The keystone correction value is stored in the government unit 223 and becomes a reference value when the keystone correction value is determined.

Thereafter, when the memory controller 224 of the control unit 220 operates, the memory 222 outputs a signal extended by x1, x2 to the left and right in the case of the line X to have the same length as the upper line, thereby displaying the image. The correction unit 230 may control the image display means (110 of FIG. 1) to output a video signal of which keystone is corrected, thereby viewing a desired image.

As described above, the LCD projector of the present invention and the keystone correction system used therein can freely change the projection direction by adjusting the angle of the reflecting mirror and can conveniently select the mounting position of the set such as floor, ceiling, wall, etc. Has the effect of providing.

BRIEF DESCRIPTION OF THE DRAWINGS The figure which shows the structure at the time of using this invention for wall hangings,

2 is a view showing a configuration when the present invention is used for a table;

3 is a view showing a state of the exit beam when the angle of the reflection mirror is changed,

4 is a view showing keystones generated when the projection direction is changed;

Fig. 5 is a block diagram showing the configuration of a keystone correction system according to the present invention.

<Explanation of symbols on main parts of the drawings>

110: image display means 120: LCD

130: projection lens 140: the first housing

150: second housing 160: first reflection mirror

170: second reflecting mirror 180: cover

210: change amount detection means 211: rack gear

212: pinion gear 213: signal conversion unit

220: control unit 221: signal input unit

222: memory 223: keystone correction unit

224: memory controller 225: panel interface

226: timing controller 227: microcomputer

230: image display correction unit

Claims (4)

An image display means, an LCD and a projection lens for sequentially passing the light formed by the image display means, a first housing for holding and holding the image display means and the LCD, and a first housing for holding and fixing the projection lens. An LCD projector comprising a second housing rotatable based on a connection portion of The second housing is formed in a "-shape" shape to fix and support the projection lens at its end, and therein the first reflection mirror for changing the path of the light passing through the LCD to the projection lens, and the second housing A second reflecting mirror which changes the path of the light passing through the LCD to the first reflecting mirror when it is rotated to have an angle of 90 ° with respect to the first housing, and passes through the LCD when the second housing is turned; And a cover which is opened so as not to block a path of light and closes a space between the first housing and the second housing when the second housing is not rotated. An image display means, an LCD and a projection lens for sequentially passing the light formed by the image display means, a first housing for fixing and holding the image display means and the LCD, and a fixing support for the projection lens, A second housing rotatable based on a connecting portion of the second housing, the second housing being formed in a L-shape to fix the projection lens at an end thereof, and a path of light passing through the LCD to the projection lens therein; A second reflecting mirror having a first reflecting mirror for changing, and a second reflecting mirror for changing the path of light passing through the LCD to the first reflecting mirror when the second housing is rotated to have an angle of 90 ° with respect to the first housing. In the LCD projector comprising: Change amount detecting means for detecting the change in the angle of the second reflection mirror to determine the amount, a control unit for determining and controlling the keystone correction amount in accordance with the output value of the change amount detecting means, and the keystone in accordance with the control signal of the control unit A keystone correction system for an LCD projector comprising an image display correction unit for controlling the image display means to output a corrected image signal. The method of claim 2, The change amount detecting means comprises a rack gear mounted to one end of the second reflecting mirror, a pinion gear meshing with the rack gear, and a signal converting portion converting the rotation amount of the pinion gear into an electrical signal. Keystone correction system for LCD projectors. The method of claim 2, The control unit may include a signal input unit for receiving an NTSC video signal or an R, G, B, H, V signal from a PC and converting the signal, a memory for receiving an output signal of the signal input unit and storing signal values for each pixel; A keystone correction unit for determining a keystone correction value according to the output signal of the change amount detecting unit, a memory controller for controlling the output of the memory according to the output signal of the keystone correction unit, and between the memory and the image display correction unit And a microcontroller for controlling the signal input unit, the memory controller, and the timing controller, and a timing controller for synchronizing synchronization between the memory controller and the panel interface.