KR101406794B1 - Backlight unit, 2D-3D switchable image display apparatus employing the same, and method of the 2D-3D switchable image display apparatus - Google Patents

Abstract

Backlight unit, a 2D / 3D combined image display apparatus and a 2D / 3D combined image display apparatus employing the same. The disclosed backlight unit includes a light guide plate having a plurality of striped light guide segments having light exit surfaces corresponding to a plurality of segment areas, the backlight unit having a light exit surface divided into a plurality of stripe- ; A first light source emitting at least six monochromatic light beams having different wavelength bands and having at least three monochromatic light sources capable of displaying a first color in combination with at least three monochromatic light sources capable of displaying a second color in combination And a light source unit having a second light source having a monochromatic light source, wherein monochromatic light having at least six different wavelength bands in each of the plurality of segment regions is sequentially emitted.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a backlight unit, a 2D / 3D combined image display apparatus and a 2D / 3D combined image display apparatus employing the backlight unit and a 2D-3D switchable image display apparatus employing the same. }

FIG. 1 schematically shows a backlight unit according to an embodiment of the present invention and a 2D / 3D combined image display apparatus employing the same.

FIG. 2 is an exploded perspective view of the backlight unit of the 2D / 3D dual display device of FIG. 1;

Fig. 3 schematically shows a schematic optical configuration of the backlight unit of Fig.

4 is a graph showing a wavelength band of each monochromatic light source in the backlight unit of Fig.

FIG. 5 schematically shows another example of a backlight unit that can be employed in the 2D / 3D dual-purpose image display apparatus of FIG.

Figs. 6 and 7 schematically show another example of a backlight unit that can be employed in the 2D / 3D combined image display apparatus of Fig.

FIGS. 8A and 8B show the order in which each monochrome field of a 3D image is scanned in the 2D / 3D dual display device of FIG.

9A and 9B show a driving method of a backlight unit synchronized with a 3D image to be scanned in the 2D / 3D combined image display apparatus of FIG.

10 shows a driving operation of a backlight unit when a 2D image is scanned on an image panel in the 2D / 3D combined image display apparatus of FIG.

Description of the Related Art

10 ... 2D / 3D combined image display device 11 ... image panel

12 ... light source units 13, 23, 33 ... light guide plate

14 ... light-guiding segment 15 ... light-

17 ... reflector 19,29,39 ... backlight unit

50 ... Glasses R1, R2, G1, G2, B1, B2 ... Monochromatic light source

S ₁ , S ₂ , S ₃ , S ₄ , S ₅ , S ₆ , ... , S _{N -1} , S _N, ...,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backlight unit and a 2D / 3D dual display image display apparatus and a driving method of the 2D / 3D dual display image display apparatus employing the same, and more particularly, And a driving method of a 2D / 3D combined image display apparatus and an image display apparatus employing the backlight unit.

As technology develops, a video display device that displays a more realistic image is being demanded. Accordingly, there has been developed a 3D image display device capable of displaying a stereoscopic image in addition to the development of a high-resolution image display device in which pixels for displaying an image are increased. Such a 3D image display device can be applied not only to a TV but also to various fields such as a medical image, a game, an advertisement, an education, a military, and the like.

Stereoscopic images are made by the principle of stereoscopic vision through the two eyes of a person. Binocular parallax, which occurs because the eyes are separated by about 65mm, is the most important factor of the stereoscopic effect. The stereoscopic effect can be easily expressed if the same image as the actual visual image can be input into the two eyes by focusing on this. To do this, two cameras with the same characteristics are spaced apart from each other by a gap, and the left image taken by the left camera is displayed on the left eye only, and the right image taken by the right camera is displayed on the right eye only.

The 3D image display device includes a video display device using glasses and a video display device having no glasses. The image display apparatus using glasses includes a polarized spectacle type system and a shutter spectacular type system. A non-spectacle type image display apparatus for obtaining a stereoscopic image by separating left and right images without using glasses is provided with a parallax barrier system, a lenticular lenticular method, an integral imaging method, and a holography method. In the polarizing spectacles-type image display apparatus using spectacles, a device for sequentially converting polarized light is required in order to allow the right and left images to be formed of different polarized lights, and the shutter spectacles- There is a problem that the structure is complicated and the cost is increased.

The present invention has been conceived to solve the problems of the conventional 3D image display apparatus described above, and it is a backlight unit capable of displaying a 3D image without significantly changing the configuration of a color sequential driving type image display apparatus and And to provide a driving method of a 2D / 3D combined image display apparatus and a 2D / 3D combined image display apparatus.

In order to achieve the above object, a backlight unit according to the present invention is a backlight unit in which a light output surface is divided into a plurality of stripe-shaped segment regions and is driven in a time division manner, the backlight unit having a light output surface corresponding to the plurality of segment regions A light guide plate having a plurality of stripe-shaped light guide segments; A first light source emitting at least six monochromatic light beams having different wavelength bands and having at least three monochromatic light sources capable of displaying a first color in combination with at least three monochromatic light sources capable of displaying a second color in combination And a light source unit having a second light source having a monochromatic light source, wherein monochromatic lights having at least six different wavelength bands are successively emitted from each of the plurality of segment regions.

According to an aspect of the present invention, there is provided a 2D / 3D combined image display apparatus including: an image panel on which an image is formed; And the above backlight unit by supplying light to the image panel.

According to another aspect of the present invention, there is provided a method of driving a 2D / 3D combined image display apparatus, the method comprising: decomposing one frame of an image into a monochromatic field corresponding to monochromatic light having at least six different wavelength bands; And sequentially driving the corresponding monochromatic light source for each of the plurality of segment areas in accordance with the synchronous signal of the scanned monochromatic field.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the embodiments illustrated below are not intended to limit the scope of the invention, but rather to provide a thorough understanding of the invention to those skilled in the art. In the following drawings, like reference numerals refer to like elements, and the size of each element in the drawings may be exaggerated for clarity and convenience of explanation.

1 to 4 illustrate a backlight unit according to an embodiment of the present invention and a 2D / 3D combined image display apparatus employing the same. FIG. 1 schematically shows an optical configuration of a 2D / 3D combined image display device according to the present embodiment, and FIGS. 2 and 3 show an example of a backlight unit employed in a 2D / 3D combined image display device of this embodiment . 4 is a graph showing a wavelength band of each monochromatic light source.

1, the 2D / 3D combined image display apparatus according to the present embodiment includes an image panel 11 in which an image is formed, and a backlight unit 19 for supplying light to the image panel 11 An image display device 10 and glasses 20 worn by a user to view a 3D image displayed on the image display device 10. [

The image panel 11 is an image device in which a 2D image or a 3D image is displayed according to an input image signal. The image panel 11 of the present embodiment is a light-receiving type image element which separately requires a backlight unit 11 that does not emit light and supplies light. In addition, the image panel 11 does not have a color filter per se, but implements color by supplying monochromatic light sequentially from the backlight unit 11. The image panel 11 can employ a normal image element for realizing a 2D image as it is. As such an image panel 11, for example, a conventional liquid crystal panel can be employed.

The backlight unit 19 is placed on the back surface of the image panel 11 and illuminates the surface thereof. The backlight unit 19 is time-divisionally driven in the scanning direction in synchronism with the image to be scanned on the image panel 11. 2 and 3, the backlight unit 19 of the present embodiment is of a side-emitting type and includes a light guide plate 13, a light source unit 12 disposed on both sides of the light guide plate 13, .

The light source unit 12 emits monochromatic light having at least six different wavelength bands and is composed of a first light source having three monochromatic light sources (R1, G1, B1) capable of displaying a first color (RGB1) And a second light source 12R having three monochromatic light sources R2, G2 and B2 capable of displaying a second color RGB2 in combination. As the monochromatic light sources R1, G1, B1, R2, G2 and B2, for example, a light emitting element such as an LED or a small lamp can be employed. The first light source 12L is a light source for left image as described later, and the second light source 12R is a light source for commercial use.

The first light source 12L includes a first red light source R1 that emits a first red light, a first green light source G1 that emits a first green light, a first blue light source B1 that emits a first blue light, The second light source 12R includes a second red light source R2 for emitting a second red light, a second green light source G2 for emitting a second green light, a second red light source G2 for emitting a second blue light, 2 blue light sources B2. Each of the first red light source R1, the first green light source G1, the first blue light source B1, the second red light source R2, the second green light source G2 and the second blue light source B2, They have different wavelength bands as shown in Fig. That is, the first and second red light sources R1 and R2 emit red light of different wavelengths, the first and second green light sources G1 and G2 emit green light of different wavelengths, Two blue light sources (B1, B2) emit green light of different wavelengths. This is for the purpose of separating the left and right images according to the wavelength band as described later. The wavelength band of each of the first and second red light R 1 and R 2 may be, for example, 600 to 650 nm and 650 to 700 nm, and the wavelength of each of the first and second red light R 1 and R 2, The wavelength band of each of the first and second blue light beams B1 and B2 may be, for example, 400 to 450 nm, 450 to 500 nm, and 500 to 550 nm, for example, nm. Since the first light source 12L and the second light source 12R each include a tricolor light source of red, green, and blue, a color can be expressed by a combination of the respective monochromatic light sources.

The first light source 12L of the present embodiment has a first red light source R1, a first green light source G1 and a first blue light source B1, but may further include a monochromatic light source of another color, However, the wavelength band of the added monochromatic light source may be different from the wavelength band of the monochromatic light sources belonging to the second light source 12R. Similarly, the second light source 12R may further include a monochromatic light source other than the second red light source R2, the second green light source G2, and the second blue light source B2, The band may be different from the wavelength band of the monochromatic light sources belonging to the first light source 12L. Furthermore, if the color can be expressed, the monochromatic light sources of the light source unit 12 are not necessarily limited to the three-color light sources of red, green, and blue.

The light guide plate 13 turns the light illuminated by the light source unit 12 into a surface light source and illuminates the image panel 11. The light guide plate 13 is disposed so that its light output surface faces the back surface of the image panel 11. [ The light exit surface of the light guide panel 13 is divided in the stripe-shaped N-segment region _{(S 1, S 2, S} 3, S 4, S 5, S 6, ..., S N -1, S N), And are sequentially illuminated. To this end, the light guide plate 13, the N segment area having the light exit surface corresponding to (S _1, S _2, S _3, S _4, S _5, S _6, ..., S _{N -1,} S _N) N light guide segments 14 are arranged side by side. At this time, the division of the light exit surface of the light guide plate 13, a segment region having a stripe structure _{(S 1, S 2, S} 3, S 4, S 5, S 6, ..., S N -1, S N) So that the longitudinal direction is perpendicular to the direction in which the image is scanned in the image panel 11. [ The direction sequentially illuminated in the backlight unit 19 is made to coincide with the direction in which the image is scanned in the image panel 11 (see Figs. 9A and 9B). On the other hand, N is the number of division of the light exit surface for time-division driving of the backlight unit 19, and a person skilled in the art will be able to select an appropriate division number.

It is preferable that a light shielding film 15 is formed on an interface between the N light guide segments 14. This is to prevent light from leaking between the adjacent light guide segments 14 to deteriorate the image quality. The light shielding film 15 is preferably a reflective coating film which can easily reflect light, but it is also possible to use a black coating film for absorbing light.

The first light source 12L and the second light source 12R of the light source unit 12 are respectively disposed at both ends of the N light guide segments 14 as shown in the figure and are independent of each light guide segment 14 As shown in FIG. Each of the light guide segments 14 includes a first red light source R1, a first green light source G1 and a first blue light source B1 and a second red light source B1 belonging to the first light source 12L, The red light source R2, the second green light source G2, and the second blue light source B2 are all disposed. In the present embodiment, the first light source 12L and the second light source 12R are staggered with respect to the adjacent light guide segments 14. As described later, when the illumination for the left image is performed as described later, the first light sources 12L are illuminated while being offset from each other on both sides of the light guide plate 13. When illuminating the illumination for the right image The second light sources 12R are illuminated by being staggered from each other on both sides of the light guide plate 13, thereby enabling more uniform surface illumination. For example, the first light source 12L may be disposed on one side of the light guide plate 13 and the second light source 12R may be disposed on the other side of the light source 13 .

The backlight unit 19 of this embodiment has a configuration in which the light source unit 12 is disposed at both ends of the light guide plate 13, but the present invention is not limited thereto.

5 schematically shows another example of a backlight unit that can be employed in the 2D / 3D combined image display apparatus of the present invention. As shown in Fig. 5, the backlight unit 29 may have a configuration in which the light source unit 12 is disposed only on one side of the light guide plate 23. In this case, the each light guide segment 24. The first and second light sources are all disposed, each segment region (S _1, S _2, S _3, S _4, S _5, S _6, ..., S _{N -1} , And S _N , it is necessary to be able to emit all the monochromatic light that can express the first and second colors RGB 1, 2.

As another example, a backlight unit 39 of a direct type as shown in Figs. 6 and 7 is also possible. In this case, the backlight unit 39 includes a light guide plate 33 having a plurality of light guide segments 34, a light source unit 32 disposed on the back surface of each light guide segment 34, And a reflection plate 37 for allowing the light to be efficiently incident on each light guiding segment 34. As the light source unit 32, for example, a linear light source such as a cold cathode fluorescent lamp (CCFL) external electrode fluorescent lamp (EEFL) may be employed. Furthermore, the backlight unit of the present invention may employ a stripe-shaped surface light source itself which does not require a separate light guide plate.

The glasses 50 are configured such that the left glasses 51 and the right glasses 52 have different optical characteristics. For example, the left eyeglass 51 is coated with a filter for passing the monochromatic light emitted from the first light source 12L and blocking the monochromatic light emitted from the second light source 12R. The right eyeglass 52 is coated with a first light source 12L may be coated with a filter that cuts off the monochromatic light emitted from the first light source 12R and transmits the monochromatic light emitted from the second light source 12R. The monochromatic lights having passed through the left eyeglasses 51 are combined to form an image of the first color RGB1 and the monochromatic lights having passed through the right eyeglasses 52 are combined to form the image of the second color RGB2. In order for the user to view the 3D image, the left and right image signals are alternately input to the image panel 11, and the left and right images are displayed on the image panel 11 in a time-division manner, 50 to separate the left and right images.

Next, a driving method of the 2D / 3D dual display device of the present invention will be described with reference to FIGS. 8A to 10.

First, a driving method for displaying a 3D image will be described.

The 2D / 3D combined image display apparatus of the present invention divides a 3D image into red, green, and blue fields for each of the left and right images in a signal processing unit, and displays the 3D image sequentially on the image panel. That is, the image of one frame is divided into the R1, G1, and B1 fields, which are the left images, and the R2, G2, and B2 fields, which are the right images. The left and right images are images that are taken in different directions and generate binocular parallax. The R1, G1, and B1 fields of the left image correspond to the first red light, the first green light, and the first blue light, respectively, and the R2, G2, and B2 fields of the right image correspond to the second red light, the second green light, Respectively. For the image having a frame rate of 60 Hz, the R1, R2, G1, G2, B1, and B2 fields are sequentially displayed on the image panel in 1/360 second increments.

8A shows an example of the order in which each monochrome field of a 3D image is scanned. Referring to the drawings, the left image and the right image are alternately displayed for respective monochromatic colors. That is, an image is displayed on the image panel in the order of the R1 field of the left image, the R2 field of the right image, the G1 field of the left image, the G2 field of the right image, the B1 field of the left image, and the B2 field of the right image. However, the display order of the monochromatic field of the present invention is not limited to this. For example, as shown in FIG. 8B, the R1, G1, and B1 fields of the left image are sequentially displayed, and then the R2, G2, and B2 fields of the right image may be sequentially displayed. When the display order of the monochromatic field is changed in this way, the driving sequence of the corresponding monochromatic light source of the backlight unit described later is changed.

9A and 9B show a driving method of a backlight unit synchronized with each monochrome field scanned on the image panel. Referring to FIG. 3, the first light source is driven while the left image of the 3D image is displayed on the image panel, and the second light source is driven while the right image of the 3D image is displayed on the image panel. Further, the image of each monochromatic field is formed by scanning each pixel information line by line in the image panel and scanning in a direction perpendicular to the line. The backlight unit is formed by dividing each segment area S ₁ , S ₂ , S ₃ , S ₄ , S ₅ , S ₆ , ..., S _{N -1} , S _N ) are sequentially driven to emit monochromatic light corresponding to the monochromatic field. For example, while the R1 field of the left image being scanned on the image panel, the first light source (12L) is, each segment region corresponding to where the R1 field of the left image being scanned on the image panel (S _1, S _2, S ₁ , S ₃ , S ₄ , S ₅ , S ₆ , ..., S _{N -1} , and S _N sequentially emit the first red light. Next, while the R2 field of the right image is being scanned on the image panel, the second light source 12R outputs the segment field S ₁ , S ₂ , S (corresponding to the position where the R2 field of the left image is scanned on the image panel ₃ , S ₄ , S ₅ , S ₆ , ..., S _{N -1} , and S _N sequentially emit the second red light, the second red light source R2 is driven in accordance with the scanning direction. Likewise, the G1 field of the left image, the G2 field of the right image, the B1 field of the left image, and the B2 field of the right image are sequentially scanned on the image panel, and the respective monochromatic light sources of the corresponding backlight unit are sequentially driven. On the other hand, since the backlight unit of this embodiment is designed so that the monochromatic light emitted from each light guiding segment does not touch the neighboring light guiding segment, when the image of one monochromatic field is scanned to a certain portion, Can be scanned. In this case, different monochromatic light sources corresponding to the different light-guiding segments may be simultaneously lighted.

Since the first and second light sources 12L and 12R are arranged so as to be offset from each other at both ends of each light guide segment 13, the monochromatic light is incident on both sides of the light guide plate 13 while being staggered from each other, Can be more uniformly illuminated when viewed from the light exit surface of the light guide plate 13.

Next, a process of displaying a 2D image will be described.

In the 2D / 3D combined image display apparatus of the present invention, a 2D image in which the left and right images are not separated is separated into a red field, a green field, and a blue field by a signal processing unit not shown and sequentially displayed on the image panel. For an image having a frame rate of typically 60 Hz, each monochrome field is sequentially displayed on the image panel in 1/180 second increments.

10 shows a driving operation of a backlight unit when a 2D image is scanned on an image panel in the 2D / 3D combined image display apparatus of FIG. Referring to the drawings, the first and second light sources are simultaneously driven while the 2D image is displayed on the image panel. For example, while the red field is being scanned on the image panel, each segment region (S ₁ , S ₂ , S ₃ , S ₄ , S ₅ , S ₆ , S _{N -1} , and S _N ) simultaneously drive the first and second red light sources R 1 and R 2 in the scanning direction so as to simultaneously emit the first and second red lights. Next, a green field and a blue field are sequentially displayed, so that a 2D image of one frame can be displayed. In the 2D / 3D combined image display apparatus of the present invention, the user does not need to wear glasses to watch a 2D image. The method of displaying the 2D image is substantially the same as the method of displaying the image in the conventional image display device.

INDUSTRIAL APPLICABILITY As described above, the backlight unit according to the present invention and the driving method of the 2D / 3D dual-purpose image display apparatus and the 2D / 3D dual- The 3D image can be easily implemented by changing the image signal processing unit which adopts the backlight unit of the present invention instead of the conventional backlight unit and performs the image processing with the left image and the right image. Further, the image signal is processed so as not to separate the left and right images, and a 2D image can be seen when the glasses are not worn. The 2D / 3D combined image display apparatus of the present invention can be applied to various industrial applications such as a three-dimensional stereoscopic game image device, a broadcast 3D TV, a stereoscopic display, a military 3D display, a 3D display for simulation training, It can be applied to the field. ,

The backlight unit of the present invention and the driving method of the 2D / 3D dual-purpose image display apparatus and the 2D / 3D dual-purpose image display apparatus employing the backlight unit have been described with reference to the embodiments shown in the drawings for illustrative purposes only, It will be understood by those skilled in the art that various changes and modifications may be made without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the appended claims.

Claims (12)

A backlight unit in which a light output surface is divided into a plurality of stripe-shaped segment regions for time-division driving, A light guide plate having a plurality of light guide segments in a stripe shape having light exit surfaces corresponding to the plurality of segment areas; And a light source unit for emitting monochromatic light having at least six different wavelength bands, Wherein the light source unit includes a first light source having at least three monochromatic light sources of different wavelength bands capable of displaying a first color in combination with at least three monochromatic light sources of different wavelength bands capable of displaying a second color, Wherein at least three monochromatic light sources of the first light source and at least three monochromatic light sources of the second light source are light sources of different wavelength bands, Wherein monochromatic light having at least six different wavelength bands is successively emitted from each of the plurality of segment regions. The method of claim 1, Wherein the first light source comprises a first red light source, a first green light source, and a first blue light source, Wherein the second light source comprises a second red light source, a second green light source, and a second blue light source. The method of claim 1, Wherein the first light source and the second light source are respectively disposed at both ends of each of the plurality of light guide segments. 4. The method of claim 3, Wherein the first light source and the second light source are staggered with respect to adjacent light guide segments. The method of claim 1, Wherein the first light source and the second light source are disposed together at one end of each of the plurality of light guide segments. The method of claim 1, Wherein the first light source and the second light source are disposed on the back side of each of the plurality of light guide segments facing the light exit surface of each of the plurality of light guide segments. The method of claim 1, And a light blocking film is formed on an interface between the plurality of light guide segments. An image panel on which an image is formed; And a backlight unit according to any one of the first to seventh aspects by supplying light to the image panel. 9. The method of claim 8, A first light source for transmitting monochromatic light emitted from the first light source and blocking monochromatic light emitted from the second light source and a monochromatic light emitted from the first light source, And a display unit for displaying the 2D / 3D image. A method for driving a 2D / 3D combined image display apparatus according to claim 8, Each frame of the image is decomposed into a monochromatic field corresponding to monochromatic light having at least six different wavelength bands, the decomposed monochromatic field is scanned on the image panel, And sequentially driving the corresponding monochromatic light source for each of the plurality of segment regions in accordance with the synchronous signal of the scanned monochromatic field. 11. The method of claim 10, When the image panel displays a 3D image, Each frame of the left image is decomposed into at least three left image monochrome fields corresponding to monochromatic light sources of the first light source, Decomposing each frame of the right image into at least three right image monochrome fields corresponding to monochromatic light sources of the second light source, Scanning the at least three left-eye video monochrome fields and the at least three right video monochrome fields sequentially or crossing the video panel, The method comprising: driving a monochromatic light source of a corresponding first light source in accordance with each sync signal of at least three left-eye image monochromatic fields to be scanned, matching the respective sync signals of at least three right-eye monochromatic fields to be scanned, And the driving of the monochromatic light source of the 2D / 3D combined image display device is performed. 11. The method of claim 10, When the image panel displays a 2D image, And simultaneously drives the monochromatic light sources of the first light source and the monochromatic light sources of the second light source corresponding to the respective monochromatic fields of the 2D image according to the synchronous signal of each monochromatic field of the 2D image scanned on the image panel A driving method of a 2D / 3D combined image display apparatus.

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