KR20170054691A

KR20170054691A - Stereoscopic Image Display Device And Method For Driving the Same

Info

Publication number: KR20170054691A
Application number: KR1020150157150A
Authority: KR
Inventors: 허태영
Original assignee: 엘지디스플레이 주식회사
Priority date: 2015-11-10
Filing date: 2015-11-10
Publication date: 2017-05-18

Abstract

A stereoscopic image display apparatus capable of minimizing the luminance reduction in the case of driving in 2D while achieving slimness of the stereoscopic image display apparatus and simultaneously ensuring a uniform viewing distance of the stereoscopic image without a 3D crosstalk, The three-dimensional image display apparatus according to the present invention is characterized in that the sub pixels located on the first horizontal line are provided with a barrier provided with a light shielding pattern including an opening for exposing a part of the sub pixels, The light blocking pattern is not formed in the subpixels located on the line, the image is displayed using all of the subpixels during the 2D driving, and the subpixels positioned on the first horizontal line are used during the 3D driving The subpixels located on the second horizontal line then represent a plurality of views to display a black or gray image Wherein the plurality of views are alternately displayed in subpixels corresponding to the openings arranged in the first horizontal line and in the openings arranged in the first horizontal line in another adjacent horizontal line group, At this time, when the period of the opening and the pitch of the subpixels are different, and thus the aperture is located between two subpixels, one of the two subpixels displays a black or gray image.

Description

Technical Field [0001] The present invention relates to a stereoscopic image display device and a driving method thereof,

The present invention relates to a stereoscopic image display device, which aims at slimming a stereoscopic image display device, enhancing a luminance during 2D driving while securing an optical viewing distance of a certain level or more, and preventing a black band phenomenon and a crosstalk phenomenon To a stereoscopic image display device capable of 2D display and a driving method thereof.

The stereoscopic image display apparatus can be divided into an eyeglass system and a non-eyeglass system depending on the presence or absence of glasses.

Among them, the non-eyeglass system implements a 3D image by installing an optical element in front of the display screen, which can cause a parallax between the left eye image and the right eye image. Examples of the optical element having such a function include a lenticular lens and a parallax barrier.

The parallax barrier includes vertical slits for transmitting or blocking light, and the left and right images are separated through the slits to realize a stereoscopic image. The lenticular lens has a bendable lenticular array type lens attached to the display panel The left and right images are separated by allowing the left and right eyes to see pixels different from each other, thereby realizing a stereoscopic image.

However, in the conventional stereoscopic image display apparatus, the optical viewing distance is generally determined by the pitch of the unit lens of the parallax portion or the unit slit of the specific period. However, Do.

Therefore, in order to increase the optical viewing distance, a separate gap glass is provided before or after the parallax portion. However, in this case, there is a problem that the thickness of the stereoscopic image display device is increased, .

Meanwhile, in the conventional stereoscopic image display apparatus, when dividing the screen into a plurality of views (hereinafter, referred to as 'views'), the view images are superimposed on each other to eliminate the luminance deviation. The stereoscopic image display device has a problem that the cross-talk phenomenon is increased by overlapping the view images.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the above-mentioned problems, and it is an object of the present invention to provide a stereoscopic image display device which is slim, at the same time can secure an optical viewing distance over a certain level without a 3D crosstalk, Dimensional image display apparatus capable of minimizing a reduction in the number of pixels of a three-dimensional image.

According to an aspect of the present invention, there is provided a stereoscopic image display apparatus including a barrier provided with a light-shielding pattern including an opening for exposing a part of the subpixel in subpixels positioned on a first horizontal line, The shielding pattern is not formed in the subpixels located on the second horizontal line, the image is displayed using all of the subpixels while the 2D driving is performed, and the subpixels positioned on the first horizontal line are displayed So that the subpixels located on the second horizontal line then display a black or gray image.

Meanwhile, in the stereoscopic image display apparatus of the present invention, the period of the opening portion and the pitch of the subpixels are different, and accordingly, one subpixel is opened through two openings. At this time, the subpixels opened through the two subpixels display a black or gray image.

The plurality of views are alternately displayed on the subpixels corresponding to the openings arranged in the first horizontal line located in another horizontal line group adjacent to the subpixels corresponding to the openings located in the first horizontal line.

The stereoscopic image display apparatus according to the present invention not only achieves slimming of the stereoscopic image display apparatus but also has an advantage that it can ensure a uniform viewing angle with a certain degree of optical viewing distance or more without a 3D crosstalk.

Further, in the stereoscopic image display device according to the present invention, about 50% of all the subpixels are not shielded by the light-shielding pattern in the 2D driving, so that the brightness at the time of 2D driving greatly increases.

Since the three-dimensional image display device according to the present invention displays different views in the horizontal direction, it is possible to prevent a black line phenomenon that may occur when the same view is displayed in the horizontal direction. At this time, The black band phenomenon can be prevented. At the same time, in the stereoscopic image display apparatus according to the present invention, when one opening is correspondingly positioned in two adjacent subpixels, one of the two subpixels displays a black or gray image, thereby preventing 3D crosstalk.

1 is a schematic view showing a stereoscopic image display apparatus according to the present invention.
FIGS. 2 to 3 are diagrams for illustrating shielding patterns of a bottom barrier provided in the stereoscopic image display apparatus according to the present invention.
4 is an exemplary view for explaining the shape of a lens provided in the parallax portion.

Prior to the present invention, a three-dimensional image display apparatus of a bottom barrier type in which a lower surface barrier is positioned on a lower surface of a display panel and a parallax is positioned on an upper surface of the display panel has been filed.

The stereoscopic image display device having such a new structure not only achieves slimming of the stereoscopic image display device but also has an advantage that the optical viewing distance over a certain level can be ensured with uniform luminance without 3D crosstalk.

The bottom barrier of the stereoscopic image display device may be formed by opening only a part of the subpixel of the display panel to reduce the optical pitch of the image panel in a predetermined view so that optical viewing is inversely proportional to the optical pitch It is possible to increase the optical viewing distance of the stereoscopic display panel by using the characteristics of the distance.

As a result, the stereoscopic image display device of the new structure has a problem that the light in a part of the subpixel of the display panel is cut off, and as a result, the luminance of the stereoscopic image display device is reduced.

Particularly, the stereoscopic image display device can be designed to be capable of both 2D / 3D driving. In this case, since the user is often driven in the 2D mode, there is a need to minimize the luminance reduction in the 2D mode of the stereoscopic image display device Was raised.

In addition, the stereoscopic image display device of the new structure displays images of the same view in the horizontal direction and images of different views in the vertical direction. As a result, as the number of display views of the image increases, And the present invention has the object of solving the black line phenomenon as described above.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. Like reference numerals throughout the specification denote substantially identical components. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description, a detailed description of known technologies or configurations related to the present invention will be omitted when it is determined that the gist of the present invention may be unnecessarily obscured. The component names used in the following description are selected in consideration of easiness of specification, and may be different from the parts names of actual products.

1 is a schematic view showing a stereoscopic image display apparatus according to the present invention.

A stereoscopic image display apparatus according to the present invention includes a display panel 200 having a plurality of subpixels in a matrix form and displaying an image, a display panel 200 located on the display panel 200, And includes a parallax part 500 and a bottom barrier 300 which is located on the lower surface of the display panel 200 and has an opening 401 for opening only a part of the subpixel.

On the other hand, the light source unit 100 shown in the drawing transmits light upward from a light source arranged on a side or a lower side, and includes a light source and a plurality of optical sheets. The light source unit 100 may be omitted depending on the type of the display panel 200. For example, when the display panel 200 is a display panel using a self-luminous display device such as an organic light emitting display panel or an electrophoretic display panel, the light source unit 100 may be omitted, In the case of a light-receiving type device such as a display panel, a light source unit 100 is provided.

A light source used in the light source unit 100 may be a fluorescent lamp array, a light emitting diode (LED), a laser light source array, or the like. In order to induce surface emission from the lower side to the display panel 200, And may include a plurality of the same optical sheets.

The barrier 300 has regularly arranged openings 401. The openings 401 open only a part of the subpixels of the display panel 200 and allow the display panel 200 ), It is possible to increase the optical viewing distance of the stereoscopic image display device due to the characteristic of the optical viewing distance (OVD) that is inversely proportional to the optical pitch under the optically same gap condition. Here, the bottom barrier 300 allows the light corresponding to a part of the images of different views transmitted to the display panel 200 to be emitted to the parallax portion on the upper side of the display panel.

The stereoscopic image display apparatus according to the present invention differs from the stereoscopic image display apparatus according to the present invention in that a gap glass having a thickness of about 5 mm or more is included in a conventional three- So that the thickness of the patterned light-shielding pattern does not substantially affect the summed thickness of the display panel 200 and the parallax portion 500 at a level of 0.05 mu m to 0.3 mu m. Accordingly, a stereoscopic image display device having a parallax and bottom barrier on the top and bottom surfaces of the display panel, respectively, and maintaining a slimmed state, thereby increasing the optical viewing distance can be realized.

In addition, the parallax part 500 is, for example, a lenticular lens array in which lenses having a long and constant pitch in the longitudinal direction are regularly arranged. The lenticular lens array may be a lens having a constant curvature, or may be a switchable lens array in which a change in refractive index is controlled by on / off by a voltage. In the case of a switchable lens array, the stereoscopic image display apparatus can selectively display 3D / 2D by turning on / off the switchable lens array. In this case, the most basic form of the switchable lens array includes first and second substrates opposed to each other, a liquid crystal layer between the first and second substrates, a common electrode on the second substrate, And a plurality of first electrodes corresponding to a lens region corresponding to a pitch.

In the case of 3D display, the switchable lens array applies the highest voltage to the first electrode located at the center of the lens region and applies a gradually lowering voltage toward the center of the lens region, And is driven by applying the lowest voltage among the voltages applied to the electrodes. At this time, the refractive index becomes the smallest at the center of the lens region and the refractive index gradually increases as the distance from the center increases, so that the optical refractive index difference such as the lenticular lens is obtained, and the image from the display panel 200 is separated according to the viewpoint.

Also, in the case of a 2D display, the switchable lens array functions as a transparent film by eliminating the refractive index difference between the first electrodes and the common electrode, so that the image of the lower display panel is output as it is.

In the present invention, it is preferable that the parallax unit 500 is formed of the switchable lens array so as to be able to be driven in both 2D and 3D.

The display panel 200 may be classified into a transmissive type display panel and a light receiving type display panel. 1 shows a stereoscopic image display device provided with a light source unit 100. In this case, the stereoscopic image display device is assumed to be a light-receiving display panel. However, if the light source unit 100 is omitted, the stereoscopic image display apparatus can be implemented only in the order of the barrier 300, the display panel 200, and the parallax unit 500.

When the display panel 200 is a liquid crystal panel, the display panel 200 includes a lower plate 210 and an upper plate 220 opposed to each other, a liquid crystal layer filled therebetween, a thin film transistor array on the lower plate side, And a color filter array.

The liquid crystal cells are driven by an electric field between a pixel electrode to which a data voltage is supplied through a TFT and a common electrode to which a common voltage is supplied. The gate electrode of the TFT is connected to the gate line, the source electrode of the TFT is connected to the data line, and the drain electrode of the TFT is connected to the pixel electrode of the liquid crystal cell. The TFT is turned on according to the gate pulse supplied through the gate line to supply the data voltage from the data line to the pixel electrode of the liquid crystal cell.

When the display panel is an organic light emitting panel, the display panel 200 includes a driving transistor array (not shown) provided on the lower plate 210 and an organic light emitting diode array (not shown) (Not shown). Meanwhile, the upper plate 220 may not be provided at this time.

Each sub-pixel is provided with an organic light emitting element composed of an organic light emitting layer between the anode and the cathode, and a pixel circuit for independently driving the organic light emitting element.

The pixel circuit includes at least one switching transistor, at least one capacitor, and a driving transistor. The plurality of switching transistors charges a data signal in a capacitor in response to a scan signal generated every horizontal period. The driving transistor supplies a constant voltage to the organic light emitting element in accordance with the data voltage charged in the capacitor to drive the organic light emitting element.

In order to drive the display panel 200, the three-dimensional image display apparatus according to the present invention further includes a gate driver for driving the gate lines, a data driver for driving the data lines, and image data from outside, And a timing controller for generating a gate and a data control signal to control the gate and the data driver.

The display panel 200 may further include a first polarizer 110 and a second polarizer 120 on the top and bottom of the display panel 200. The first and second polarizing plates 110 and 120 may be omitted from one side or both sides depending on the type of the display panel 200. [

On the other hand, the light shielding pattern of the bottom barrier 300 of the present invention is formed only on the lower surface of the subpixels located on the odd horizontal line, or only on the lower surface of the subpixels located on the even horizontal line . Accordingly, the entire area of the sub-pixels on the horizontal line where the light-shielding pattern is not formed is opened.

In the present invention, a horizontal line in which sub-pixels in which a light-shielding pattern is formed is defined as a first horizontal line, a sub-pixel in which no light-shielding pattern is formed is defined as a horizontal line, And the second horizontal line may be defined as one horizontal line group. The display panel 200 includes the plurality of horizontal line groups.

The subpixels located on the second horizontal line H2, which is opened as a whole, are used for 2D image display during 2D driving of the stereoscopic image display apparatus, and the subpixels display a black or gray image And is not used for 3D image display.

In the stereoscopic image display device according to the present invention having the bottom barrier 300 as described above, about 50% of all the subpixels are not shielded by the light shielding pattern during the 2D driving, so that the luminance during the 2D driving increases greatly.

In the stereoscopic image display apparatus according to the present invention, a plurality of views are not superimposed and displayed, and only one view is displayed in each subpixel.

Hereinafter, an embodiment of the barrier 300 will be described in more detail with reference to the drawings.

FIGS. 2 and 3 are diagrams for explaining the light shielding pattern 400 of the bottom barrier 300 provided in the stereoscopic image display device according to the present invention. Here, the parallax part 500 is shown for explaining the pitch of the lens provided in the parallax part 500 and the period of the opening part 401. Here, the light shielding pattern 400 is formed on the lower surface of the sub pixel SP 2 to 3 show the surface to be displayed.

2 to 3, the light shielding pattern 400 is formed to expose a part of each subpixel SP only on the subpixel SP provided on the first horizontal line H1.

The entire area of the subpixels SP provided on the second horizontal line H2 on which the shading pattern 400 is not formed is opened.

Here, the period of the opening 401 refers to a horizontal gap between a time point of one opening 401 and a time point of the next opening 401 with respect to a subpixel of a horizontal line.

The width of the opening 401 is formed to correspond to the size of the period of the opening 401 divided by the number of views.

For example, FIG. 2 shows a 3-view image, the width of the opening 401 corresponds to 1/3 of the cycle of the opening 401, and FIG. 3 shows a 4-view image. Corresponds to a quarter of the period of the opening 401. [

The opening provided in the pixel corresponding to the first horizontal line H1 may include a pixel corresponding to the first horizontal line H1 belonging to another horizontal line group located at an upper position in the vertical direction in the first horizontal line H1 As compared to the openings arranged in the openings.

On the other hand, when the pitch of the subpixels SP is formed to be equal to the period of the opening 401, the area overlapping the black matrix layer is concentrated in the opening 401 displaying a specific view, A degraded black band phenomenon may occur. In order to prevent the above-described problems, the pitch of the sub-pixels SP in the present invention is formed to be different from the period of the openings 401.

2 and 3 show an embodiment in which the period of the opening 401 is formed to be larger than the pitch of the subpixels SP. However, in the stereoscopic image display apparatus according to the present invention, SP).

The lens of the parallax part 500 has the same pitch as the value obtained by multiplying the width of the opening by the number of views to be displayed. For example, the pitch of the lens provided in the stereoscopic image display device for displaying three views shown in FIG. 2 is about three times the width of the opening 401, and the three- The pitch of the lens provided in the apparatus corresponds to about four times the width of the opening 401. [

At this time, an opening 401 corresponding to a subpixel displaying an m-th view (m is a natural number equal to or smaller than k) among k views (k is a natural number of 2 or more) includes a lens provided in the parallax portion 500 k, which is formed by dividing the light-shielding film. Accordingly, the k view images are respectively separated by the lens and transmitted to the viewer.

4, the lens of the parallax part 500 may be formed in a shape in which the cylinder is cut so that the end face of the side square covers the opening 401. [

In this case, as described above, the opening provided in the pixel corresponding to the first horizontal line H1 of the opening corresponds to the first horizontal line H1 belonging to the other horizontal line group located vertically above the first horizontal line H1 Is formed to be shifted by the width of the opening portion as compared with the opening portion arranged in the pixel corresponding to the horizontal line H1. Therefore, the lens is also preferably formed to be inclined.

Referring to FIGS. 2 and 3, the plurality of views are alternately arranged on the first horizontal line H1 of the first horizontal line group G1 and the first horizontal line H2 of the second horizontal line group G2. .

For example, in the case of the three-view image display apparatus shown in FIG. 2, the sub-pixels corresponding to the first opening disposed on the first horizontal line H1 of the first horizontal line group G1 SP), two views are displayed in a subpixel SP corresponding to the first opening arranged on the first horizontal line H1 of the second horizontal line group G2, Three views are displayed in the subpixels SP corresponding to the second opening arranged on the first horizontal line H1 of the horizontal line group G1 and the three views are displayed on the first horizontal line H1 of the second horizontal line group G2, And one view is displayed in the subpixel SP corresponding to the second opening portion disposed on the first pixel H1. Thus, from the first horizontal line group G1 to the subpixels corresponding to the last opening disposed on the first horizontal line H1 of the second horizontal line group G2, The arrangement of the subpixels SP is repeated.

On the other hand, in the case of the three-view image display apparatus shown in FIG. 3, the sub-pixels SP corresponding to the first opening disposed on the first horizontal line H1 of the first horizontal line group G1 Two views are displayed in a subpixel SP corresponding to the first opening disposed on the first horizontal line H1 of the second horizontal line group G2, The three views are displayed in the subpixels SP corresponding to the second opening disposed on the first horizontal line H1 of the first horizontal line G1 and the first horizontal line H1 of the second horizontal line group G2, Four views are displayed in the subpixel SP corresponding to the second opening portion disposed on the subpixel SP. Thus, the display of the above-described view is repeated until reaching the last openings arranged on the first horizontal line H1 of the first horizontal line group G1 and the second horizontal line group G2. do.

In FIGS. 2 and 3, the plurality of views are sequentially displayed alternately in the subpixels corresponding to the openings positioned on the two horizontal lines, but the views may not be sequentially displayed alternately. For example, the view corresponds to the subpixel corresponding to the opening located in the first horizontal line of the first horizontal line group G1 and the opening located in the first horizontal line of the second horizontal line group G2 2 view-1 view, or 2 view-3 view-1 view, or 2 view-4 view-1 view-3 view, in that order.

In the present invention, since the pitch of the sub-pixel SP is different from the period of the opening 401, one opening 401 may be formed to correspond to the two sub-pixels SP. In other words, according to Figs. 2 to 3, one subpixel SP can be opened by two openings 401.

In this case, since images displaying different views are superimposed and displayed through one opening, a horizontal crosstalk phenomenon may occur.

In the present invention, in order to prevent the crosstalk phenomenon as described above, when one subpixel SP is formed to be opened through the two openings 401 as described above, the subpixels SP opened through the two openings 401 The pixel displays a black or gray image.

2 and 3 are diagrams for explaining a three-view image and a four-view image when the period of the opening 401 is larger than the pitch of the sub-pixels SP, .

2 to 3, in the stereoscopic image display apparatus of the present invention, the subpixel SP is periodically opened through two openings 401, and in this case, the subpixels SP are opened through the two openings 401, (SP) displays a black or gray image.

Accordingly, only one sub-pixel SP displays the view image in one opening 401, so that the horizontal crosstalk phenomenon is reduced.

At this time, the aperture width of the aperture 401 on the first horizontal line H1 may be periodically narrowed or some subpixels may not be displayed, but as shown in Figs. 2 to 3, The distribution of the underexposed regions of the subpixels is uniformly positioned in the openings for displaying the respective views, so that the luminance of the specific view image does not increase or decrease noticeably.

In addition, the stereoscopic image display device according to the present invention can prevent a black line phenomenon that may occur when displaying the same view in the horizontal direction. The reason for this is as follows.

As described above, in the stereoscopic image display apparatus according to the present invention, the sub pixels located in the second horizontal line H2 in the 3D driving mode display a black or gray image. Accordingly, if the same view is displayed in the horizontal direction, the period in which the same view is displayed in the vertical direction is 6 pixels for 3 view images and 8 pixels for 4 view images. Accordingly, in the case of displaying the same view in the horizontal direction as described above, black line phenomenon occurs strongly, resulting in a problem that the resolution is reduced and the viewer can recognize the black line.

On the other hand, as shown in FIG. 2 and FIG. 3, the three-dimensional image display apparatus according to the present invention is configured such that when three views are displayed in 3D driving or when four views are displayed, And even if a larger number of views are displayed, an image of the same view is displayed at a period of four pixels in the vertical direction.

Therefore, the stereoscopic image display apparatus according to the present invention greatly reduces the black line phenomenon in 3D driving as compared with the stereoscopic image display apparatus which displays the same view in the horizontal direction.

Further, according to the present embodiment, the width of the opening 401 is formed wider than in the case of displaying the same view in the horizontal direction.

In other words, when displaying the same view in the horizontal direction, the width of the opening 401 should be divided by the number of views to be displayed. However, in the present invention, the width of the opening 401 is And is fixed at 1/2 of the cycle. Accordingly, in the stereoscopic image display apparatus according to the present invention, since the shielding pattern 400 is not formed in half of the subpixels and the width of the opening 401 is increased even in the subpixel in which the shielding pattern 400 is formed, The brightness at the time is greatly improved.

The foregoing description is merely illustrative of the present invention, and various modifications may be made by those skilled in the art without departing from the spirit of the present invention. Accordingly, the embodiments disclosed in the specification of the present invention are not intended to limit the present invention. The scope of the present invention should be construed according to the following claims, and all the techniques within the scope of equivalents should be construed as being included in the scope of the present invention.

100: Light source unit 110, 120: Polarizing plate
200: display panel 210: first substrate
220: second substrate 300: lower barrier
400: Shading pattern 401:
500: Parallaxfish

Claims

A display panel including a plurality of horizontal line groups each including a first horizontal line and a second horizontal line each having a plurality of subpixels,
Wherein the display panel includes openings that are located on a bottom surface of the display panel and open only a part of each subpixel positioned in the first horizontal line so as to have a constant period, When you include a pattern barrier,
And a parallax portion having a lens region located on the upper side of the display panel and having a lens pitch corresponding to a value obtained by multiplying the number of views displayed by the display panel by the width of the opening portion,
The period of the opening of the barrier is different from the pitch of each subpixel,
In the 3D driving, when the subpixels are opened through two adjacent openings, the subpixels opened through the two openings and the subpixels located in the region where the lightpath pattern is not formed display a black or gray image / RTI >

The method according to claim 1,
And an opening provided in a pixel corresponding to one of the plurality of horizontal lines,
Wherein the width of the opening is shifted by a width of the opening arranged in pixels corresponding to a first horizontal line belonging to another horizontal line group located at an upper portion in a vertical direction in the first horizontal line.

3. The method of claim 2,
In the 3D driving, 2D / 3D (k is a natural number) in which k views (k is a natural number of 2 or more) are alternately displayed on the subpixels corresponding to the openings located in the two first horizontal lines, Video display device.

The method of claim 3,
The pitch of the lens provided in the lens region corresponds to the width of the opening multiplied by k,
The opening for exposing the subpixels representing the m-th view (m is a natural number of k or less) is a 2D / 3D Video display device.

5. The method of claim 4,
Wherein the lens region is cut in a columnar shape so as to have a sloped cross section in the same direction as the shifted direction of the opening.

And a display panel including a plurality of horizontal line groups each including a first horizontal line and a second horizontal line each having a plurality of subpixels and each of the subpixels arranged in the first horizontal line, 1. A 2D / 3D image display apparatus having a bottom barrier including an opening for only partially opening,
In the 3D driving, the sub pixels corresponding one-to-one with the opening provided in the first horizontal line represent a plurality of views,
When the subpixel is opened through two adjacent openings, the subpixel opened through the two adjacent openings displays a black or gray image,
The subpixels provided on the second horizontal line display a black or gray image,
A method of driving a 2D / 3D image display device in which all subpixels display an image at the time of 2D driving.

The method according to claim 6,
In the 3D driving, 2D / 3D (k is a natural number) in which k views (k is a natural number of 2 or more) are alternately displayed on the subpixels corresponding to the openings located in the two first horizontal lines, A method of driving a video display device.