KR20090080709A - Projector and Method for compensating a distortion of an image in thereof - Google Patents

Abstract

A projector and a method for compensating the distortion of an image thereof are provided to compensate distorted image conveniently and rapidly by comparing the distorted image with a standard image. A projector comprises an optical source part(110), an image projection part(120), a camera part(130), and a controller(150). The optical source part emits the light. The image projection part irradiates light coming out from the optical source part and projects images to a screen. The camera part photographs the image projected in the image projection part. The controller compensates the distorted image projected in the image projection part by comparing the image photographed in the camera part with a standard image.

Description

Projector and method for compensating a distortion of an image in

The present invention relates to an image projection apparatus, and more particularly, to a projector and a method for correcting image distortion thereof.

Currently, due to the limitation of the screen size of the existing TV, the development of a projection display device is prominent while the development and release of a large screen, ultra-thin display is active.

Development of a projector using display elements such as cathode ray tube (CRT), liquid crystal display (LCD), liquid crystal on silicon (LCoS), digital light processing (DLP), micro scanner, etc. The prevalence is rapidly increasing, which is not only universally used for displaying the output screen of a personal computer on a screen during presentations in schools, corporations, and public offices, but also for home-theater at home. It is used for.

1 is a structural diagram showing a conventional projector.

2 is a diagram illustrating examples of image distortion generated in a conventional projector.

Referring to FIG. 1, a conventional projector includes red / green / blue (hereinafter, abbreviated as 'R / G / B') light emitting elements 1a, 1b, and 1c, and a plurality of dichroic mirrors 2a and 2b. ), A plurality of reflecting mirrors 3a and 3b, an integrator 4, a plurality of illumination lenses 5a and 5b, a prism 6, a panel 7 and a projection lens 8 It is composed.

The R / G / B light emitting elements 1a, 1b and 1c emit red, green and blue light, respectively, and the dichroic mirrors 2a and 2b are the R / G / B light emitting elements 1a, 1b, The light emitted from 1c) is separated by transmission or reflection.

The integrator 4 shapes the light reflected through the first reflector 3a into a shape having a uniform brightness, and the light shaped by the integrator 4 includes the first illumination lens 5a and the first illumination lens 5a. It is illuminated by the panel 7 via the 2 reflector 3b, the 2nd illumination lens 5b, and the prism 6. As shown in FIG.

When the light emitted from the integrator 4 arrives, the panel 7 outputs image information to be projected by a process such as appropriate switching or reflection, and outputs the output image information to the projection lens 8. Projected images are formed on the screen.

As described above, the projector has many problems in the process of projecting the converted optical signal on the screen as the screen is enlarged.

That is, as a very basic problem, even maintaining the screen constituting the screen flat for a long time has emerged as a very difficult problem due to the large size of the screen.

In addition, there is a problem that distortion occurs in the image displayed on the screen due to the optical optical path difference between the light source and the screen in the process of projecting the converted optical signal on the rectangular screen.

That is, referring to FIG. 2, (a) of FIG. 2 shows a shape of a normal image in which distortion is not generated on the screen, and (b) and (c) of FIG. 2 are abnormal images in which distortion is generated on the screen. The shape of is shown.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to provide a projector and a method for correcting image distortion, which can easily correct distortion of an image displayed on a screen by software.

A projector according to the present invention for achieving the above object, and a light source for emitting light; An image projector for projecting an image onto a screen by irradiating light emitted from the light source unit; A camera unit for capturing an image projected by the image projector; And a controller configured to correct the distorted image projected by the image projector by comparing the image photographed by the camera unit with a pre-stored standard image.

In this case, the camera unit may be installed adjacent to the image projection direction of the image projector.

The controller may determine the amount of distortion of the photographed image on the basis of the standard image, and apply distortion to the image to be projected by the image projector by applying an amount opposite to the detected amount of distortion. It is characterized by correcting.

The image projected by the image projector and the standard image may have a mesh-shaped pattern divided into a plurality of blocks on a screen.

In this case, the controller determines a distortion amount of each block of the photographed image based on each block of the standard image, and applies distortion to the image to be projected by the image projector by the amount that is opposite to the detected distortion amount. It is characterized by correcting.

In addition, the image distortion correction method of the projector according to the present invention comprises the steps of projecting the image to the screen by irradiating light; Photographing the image projected on the screen; And a controller configured to correct the distorted image projected on the screen by comparing the photographed image with a pre-stored standard image.

According to the present invention, a projector and its image alignment adjusting method acquire a distorted image currently displayed on a screen by using a camera, and correct the distortion by comparing the distorted image with a standard image, thereby quickly and conveniently distorting the image. There is an effect that can correct the image.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals have the same reference numerals as much as possible even if displayed on different drawings.

In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

Hereinafter, a projector and a method of correcting image distortion thereof according to the present invention will be described in detail with reference to the accompanying drawings.

3 is a block diagram of an embodiment of a projector according to the present invention.

Referring to FIG. 3, the projector 100 according to the present invention includes a light source unit 110, an image projector 120, a camera unit 130, a storage unit 140, and a controller 150. It is composed.

Of course, the projector 100 according to the present invention may be configured to include other than the above-described components (power unit, key button, condenser lens, diffraction lens, color wheel, etc.) if necessary, the above-described configuration Since elements other than elements are not directly related to the present invention, a detailed description thereof will be omitted below for simplicity.

On the other hand, it should be noted that the components may be configured by combining two or more components into one component, or one component may be subdivided into two or more components as necessary when implemented in actual applications.

Hereinafter, the components of the projector 100 according to the present invention will be described.

The light source unit 110 includes a first light emitting device 110a that emits red (R) light, a second light emitting device 110b that emits green (G) light, and a third light emission that emits blue (B) light. The element 110c is comprised.

The light emitting devices 110a, 110b, and 110c may be formed of a light emitting diode (LED) and a laser diode.

The image projector 120 projects the image onto the screen by irradiating light emitted from the light source 110.

The image projector 120 according to the present invention may be provided in the form of a panel or a scanner, and the configuration of the image projector 120 according to the present invention will be described in detail with reference to FIGS. 4 and 5.

4 is a structural diagram of an embodiment of an image projector having a scanner according to the present invention.

Figure 5 is a structural diagram of another embodiment showing an image projection unit having a panel according to the present invention.

First, referring to FIG. 4, the image projector 120 according to the present invention includes a plurality of dichroic mirrors 121a, reflectors 122a, and a scanner 123a.

Of course, the image projection unit 120 according to the present invention may be configured to include other components (condensing lens, diffraction lens, etc.) other than the above-described components, if necessary, but other than the above-described components of the present invention Since it is not directly related to, for the sake of simplicity, a detailed description thereof will be omitted below.

On the other hand, it should be noted that the components may be configured by combining two or more components into one component, or one component may be subdivided into two or more components as necessary when implemented in actual applications.

Hereinafter, the components of the image projector 120 including the scanner according to an embodiment of the present invention will be described.

The dichroic mirrors 121a are mirrors capable of selectively reflecting or transmitting only light having a specific wavelength to obtain light of a desired wavelength band, and generally use interference of light.

The dichroic mirrors 121a separate the laser light emitted from the light source unit 110 and the reflector 122a reflects the laser light emitted from the dichroic mirror 121a to the scanner 123a. .

The scanner 123a reflects the laser light reflected from the reflector 122a and reflects it on the x-axis (horizontal) or y-axis (vertical) to project an image on the screen.

Next, referring to FIG. 5, the image projector 120 including the panel according to the present invention includes a plurality of dichroic mirrors 121b 'and 121b "and a plurality of reflecting mirrors 122b' and 122b". And an integrator 123b, a plurality of illumination lenses 124b 'and 124b ", a prism 125b, a panel 126b, and a projection lens 127b.

Of course, the image projector 120 according to the present invention may be configured to include other components (condensing lens, diffraction lens, color wheel, etc.) other than the above-described components, if necessary, but other components than the above-described components It is not directly related to the present invention, for the sake of simplicity, a detailed description thereof will be omitted below.

On the other hand, it should be noted that the components may be configured by combining two or more components into one component, or one component may be subdivided into two or more components as necessary when implemented in actual applications.

Hereinafter, components of the image projector 120 having a panel according to another embodiment of the present invention will be described.

The dichroic mirrors 121b 'and 121b "are mirrors that can selectively reflect or transmit only light having a specific wavelength to obtain light of a desired wavelength band, and usually use interference of light.

For example, the dichroic mirrors 121b ′ and 121b ″ include the first dichroic mirror 121b ′ at a position where blue light 110c and red light 110a cross each other. In addition, the second dichroic mirror 121b ″ may be positioned at a position where the green 110b light and the red 110a light intersect each other.

In this case, as illustrated in FIG. 5, the first dichroic mirror 121b ′ may transmit the blue 110c light and reflect the green 110b light and the red 110a light.

Meanwhile, the second dichroic mirror 121b ″ may reflect green 110b light and transmit green 110b light.

As such, the red (110a) light, the green (110b) light, and the blue (110c) light pass through the two dichroic mirrors (121b ', 121b ") to be synthesized and formed into light of various colors depending on the image to be formed. Are synthesized.

The light synthesized by the two dichroic mirrors 121b 'and 121b "is reflected to the integrator 123b through the first reflector 122b'.

The integrator 123b shapes the light reflected through the first reflector 122b 'into a shape having a uniform brightness.

The integrator 123b may be a light tunnel formed of a rod-shaped rod lens or a box-shaped mirror, a funnel, a trapezoidal optical funnel, or the like.

In addition, although not shown in FIG. 5, instead of the integrator 123b, a fly eye lens may be used.

The light shaped by the integrator 123b passes through the first illumination lens 124b ', the second reflector 122b ", the second illumination lens 124b", and the prism 126b to the panel 126b. Is illuminated.

When the light emitted from the integrator 123b arrives, the panel 126b outputs image information to be projected by an appropriate switching or reflection process, and the output image information is converted into the projection lens 127b. Projected images are formed on the screen.

The panel 126b may be any one of a digital micromirror device (DMD), liquid crystal on silicon (LCoS), and liquid crystal device (LCD). The panel 126b may be referred to as a micro switching device.

4 and 5, when the current operation state of the projector 100 is an “image distortion correction” operating state under the control of the controller 150, as shown in FIG. 6, a plurality of blocks are provided. The image having a mesh-shaped pattern divided into two is projected on the screen.

Of course, in the present invention has been described that the image projected by the image projector 120 has a rectangular mesh pattern, but the present invention is not limited thereto. That is, the image may include a mesh pattern in a polygonal shape such as a circle or a triangle as well as a mesh pattern of silk.

The camera unit 130 is installed adjacent to the image projection direction of the image projector, and captures an image having a mesh shape pattern projected by the image projector under the control of the controller 150.

The storage 140 may store a program for processing and controlling the controller 150, or may perform a function for temporarily storing input / output data.

The storage unit 140 may include a flash memory type, a hard disk type, a multimedia card micro type, a card type memory (for example, an SD or XD memory). Etc.), RAM, and ROM may include at least one type of storage medium.

In addition, the storage 140 according to the present invention includes a standard image for correcting a distorted image. In this case, the standard image has a mesh-shaped pattern divided into a plurality of blocks as shown in FIG. 6.

The controller 150 controls the overall operation of the projector 100 according to the present invention, and compares the image photographed from the camera unit 130 with a standard image previously stored in the storage unit 140 in the image projector 120. Corrects the distorted image being projected.

Hereinafter, an image distortion correction process of the controller 150 according to the present invention will be described in detail with reference to the accompanying drawings.

7 is a flowchart illustrating an image distortion correction method of a projector according to the present invention.

Referring to FIG. 7, if the operation state of the current projector 100 is an “image distortion correction” operating state according to the present invention according to a user's operation [S71], the image projector 120 is displayed on the screen. Control to project an image having a mesh pattern divided into a plurality of blocks on the screen [S72].

Next, the controller 150 drives the camera unit 130 to capture an image of the mesh pattern projected by the image projector 120 through the camera unit 130 [S73].

The controller 150 determines the amount of distortion of the image photographed through the camera unit 130 based on the standard image stored in the storage 140 [S74], and an amount opposite to the detected amount of distortion. (I) is applied to the image to be projected by the image projector 120 [S75] to correct distortion of the image projected by the image projector 120 [S76].

That is, the controller 150 determines the distortion amount of each block of the photographed image based on each block of the standard image, and the image projector 120 may project an amount that is opposite to the detected distortion amount. It is applied to an image to correct distortion of the projected image.

The controller 150 switches the operation state of the “image distortion correction” to the “image projection” operation state, and projects an image to which an amount opposite to the amount of distortion of the photographed image is applied to the screen.

As described above, according to the present invention, the image projecting unit 120 reversely distorts the image to be projected, as opposed to the distortion form of the image generated according to the positional relationship between the image projecting unit 120 and the screen and the external environment. The distortion of the image is corrected by causing the distortion amount of the image displayed on the screen and the image projector 120 to cancel each other.

Hereinafter, an operation process of the image distortion correction of the controller 150 will be described in more detail with reference to FIG. 8 as an example.

8 is an exemplary diagram illustrating an image distortion correction method according to the present invention.

First, referring to FIGS. 8A and 8B, the controller 150 may be configured by the camera unit 130 and the blocks a1 to a9 of the standard image 80 stored in the storage 140. After comparing the sizes of the blocks b1 to b9 of the photographed distorted image 90, the sizes of the captured images 90 are determined based on the blocks a1 to a9 of the standard image 80. The distortion amounts of the blocks b1 to b9 are determined.

Subsequently, referring to FIGS. 8C to 8E, the controller 150 applies an amount 92 that is opposite to the amount of distortion 91 of the detected image 90 to the standard image 80. In addition, the distortion of the image is corrected by projecting an image to be displayed in the form of the standard image 80 to which the opposing amounts 92 are applied.

It will be apparent to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit and essential features of the present invention. For example, it will be very easy for those skilled in the art to use the above-described embodiments in combination with each other.

Accordingly, the above detailed description should not be construed as limiting in all aspects and should be considered as illustrative.

The scope of the invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

1 is a structural diagram showing a conventional projector.

2 is a diagram illustrating examples of image distortion generated in a conventional projector.

3 is a block diagram of an embodiment of a projector according to the present invention.

4 is a structural diagram of an embodiment of an image projector having a scanner according to the present invention.

Figure 5 is a structural diagram of another embodiment showing an image projection unit having a panel according to the present invention.

6 is a view showing an image having a mesh-shaped pattern divided into a plurality of blocks according to the present invention.

7 is a flowchart illustrating an image distortion correction method of a projector according to the present invention.

8 is an exemplary diagram illustrating an image distortion correction method according to the present invention.

<Description of Major Symbols in Drawing>

100: projector 110: light source unit

120: image projection unit 130: camera

140: storage unit 150: control unit

Claims (9)

A light source unit emitting light; An image projector for projecting an image onto a screen by irradiating light emitted from the light source unit; A camera unit for capturing an image projected by the image projector; And And a controller configured to correct the distorted image projected by the image projector by comparing the image photographed by the camera unit with a pre-stored standard image. The method of claim 1, wherein the camera unit, And a projector adjacent to the image projection direction of the image projector. The method of claim 1, wherein the control unit, Determine the amount of distortion of the photographed image based on the standard image, and correct the distortion by applying an amount opposite to the detected amount of distortion to the image to be projected by the image projector; Projector. According to claim 1, And an image projected by the image projector and the standard image have a mesh-shaped pattern divided into a plurality of blocks on a screen. The method of claim 4, wherein the control unit, Determine the distortion amount of each block of the photographed image based on each block of the standard image, and correct the distortion by applying an amount opposite to the detected distortion amount to the image to be projected by the image projector; Projector. Projecting an image onto a screen by irradiating light; Photographing an image projected on the screen; And And a controller configured to correct the distorted image projected onto the screen by comparing the photographed image with a pre-stored standard image. The method of claim 6, wherein the correcting step, Determining an amount of distortion of the photographed image based on the standard image; And Correcting the distortion by applying an amount opposite to the determined amount of distortion to the image to be projected onto the screen. The method of claim 6, The image projected on the screen and the standard image, the image distortion correction method of the projector, characterized in that it has a mesh-shaped pattern divided into a plurality of blocks on the screen. The method of claim 8, wherein the correcting step, Determining a distortion amount of each block of the captured image based on each block of the standard image; And And correcting the distortion by applying an amount opposite to the determined amount of distortion to the image to be projected onto the screen.

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