KR20190111174A - Light modulator and holographic display device including the same - Google Patents

Abstract

The present invention relates to an optical modulator and a holographic display device including the same. According to an embodiment of the present invention, the holographic display device comprises: a backlight unit for emitting light; and an optical modulator including a plurality of pixels each including any one of first to third color filters, and modulating at least one of an amplitude and a phase of the light. The pixels are arranged in a zigzag shape. The optical modulator further includes a color filter layer on which the first to third color filters are arranged. The color filter layer includes a plurality of color filter groups. Each of the color filter groups can include a first sub-group in which the first color filters are arranged, a second sub-group in which the second color filters are arranged, and a third sub-group in which the third color filters are arranged.

Description

LIGHT MODULATOR AND HOLOGRAPHIC DISPLAY DEVICE INCLUDING THE SAME}

The present invention relates to an optical modulator and a holographic display device including the same.

Recently, as the users' demand for a display device capable of realizing a 3D image with a three-dimensional image is increased, a display device capable of expressing a 3D image has been developed in response to this.

Techniques for displaying 3D stereoscopic images in a device having a 2D image display screen, such as a liquid crystal display device, include a stereoscopic image display by a special glasses, an autostereoscopic stereoscopic display, and a holographic display method.

Of these various 3D image implementation methods, the holographic display method has recently attracted attention. There is a need for a technique capable of providing a satisfactory viewing angle in reproducing a holographic image, and a technique for developing aberration-free lenses in order to reproduce a color holographic image.

An object of the present invention is to provide a holographic display device for implementing color hologram with a simplified configuration.

A holographic display device according to the present invention comprises a backlight unit for emitting light; And a light modulator comprising a plurality of pixels each including at least one of a first color color filter, a second color color filter, and a third color color filter and modulating at least one of an amplitude and a phase of the light; The plurality of pixels are arranged in a zigzag form, and the light modulator further includes a color filter layer in which a plurality of the first color color filters, a plurality of the second color filters, and a plurality of the third color filters are arranged. The color filter layer includes a plurality of color filter groups, each of the plurality of color filter groups includes: a first subgroup in which the first color color filters are arranged; a second in which the second color color filters are arranged; And a third subgroup in which the third color color filters are arranged.

In addition, the plurality of color filter groups may be arranged along a first direction and the second direction crossing the first direction.

Further, the first color color filters are arranged to form a plurality of rows in the first subgroup, and the second color color filters are arranged to form a plurality of rows in the second subgroup, Three color color filters may be arranged to form a plurality of rows within the third subgroup.

Also, the first color color filters included in the first subgroup, the second color color filters included in the second subgroup, and the third color color filters included in the third subgroup. The numbers can be the same.

Further, a plurality of columns formed by color filters arranged in odd-numbered rows may be disposed between the plurality of columns formed by color filters arranged in even-numbered rows.

The plurality of pixels may be divided into a plurality of unit pixels, each of which includes first, second, and third sub-pixels, and the first sub-pixel includes at least one pixel including the first color color filter. The second sub-pixel may include at least one pixel including the second color filter, and the third sub-pixel may include at least one pixel including the third color filter. have.

The holographic display device may be driven in a first mode for displaying a 3D image or in a second mode for displaying a 2D image.

In addition, in the second mode, the light modulator may receive a data signal corresponding to the plurality of unit pixels from the outside.

The light of the first color may be red light, the light of the second color may be green light, and the light of the third color may be blue light.

In addition, it may further include a field lens provided on the light modulator.

An optical modulator for a holographic display device according to an embodiment of the present invention includes: a plurality of pixels for modulating at least one of an amplitude and a phase of light; A color filter layer in which a plurality of color filters included in the plurality of pixels are arranged; A plurality of data lines connected to the plurality of pixels and supplying a data signal to the plurality of pixels; And a plurality of gate lines connected to the plurality of pixels and supplying a gate signal to the plurality of pixels, wherein the color filter layer includes a plurality of color filter groups, each of the plurality of color filter groups , A first subgroup in which the first color color filters are arranged, a second subgroup in which the second color color filters are arranged, and a third subgroup in which the third color color filters are arranged.

In addition, the plurality of color filter groups may be arranged along a first direction and the second direction crossing the first direction.

Further, the first color color filters are arranged to form a plurality of rows in the first subgroup, and the second color color filters are arranged to form a plurality of rows in the second subgroup, Three color color filters may be arranged to form a plurality of rows within the third subgroup.

The first subgroup, the second subgroup, and the third subgroup may be arranged along the second direction.

Further, a plurality of columns formed by color filters arranged in odd-numbered rows may be disposed between the plurality of columns formed by color filters arranged in even-numbered rows.

According to the present invention, it is possible to provide a holographic display device implementing color hologram with a simplified configuration.

According to the present invention, the viewing angle of the holographic display device can be improved.

1 is a diagram schematically illustrating a configuration of a holographic display device according to an exemplary embodiment of the present invention.
FIG. 2 exemplarily illustrates a configuration of the display panel illustrated in FIG. 1.
FIG. 3 is a block diagram illustrating a configuration of the light modulator shown in FIG. 2.
4 is a diagram for explaining a correlation between pixel pitch and viewing field.
5 is a plan view illustrating a color filter layer according to an exemplary embodiment of the present invention.
FIG. 6 is a plan view exemplarily illustrating color filters arranged in the color filter group shown in FIG. 5.
7A is a plan view exemplarily illustrating a pixel structure of a holographic display device according to a comparative embodiment.
7B is a plan view illustrating a pixel structure of a holographic display device according to an exemplary embodiment of the present invention.
8 is a view for explaining a viewing area in a holographic display device according to a comparative example and an embodiment of the present invention.
9 is a diagram for describing a unit pixel according to an exemplary embodiment of the present invention.

Specific details of other embodiments are included in the detailed description and the drawings.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various forms. In the following description, when a part is connected to another part, it is only directly connected. It also includes a case in which another device is electrically connected in the middle. In the drawings, parts irrelevant to the present invention are omitted for clarity, and like reference numerals designate like parts throughout the specification.

Hereinafter, an optical modulator and a holographic display device including the same according to an embodiment of the present invention will be described with reference to the drawings related to the embodiments of the present invention.

1 is a diagram schematically illustrating a configuration of a holographic display device according to an exemplary embodiment of the present invention.

Referring to FIG. 1, a holographic display device according to an exemplary embodiment of the present invention may include a display panel DP and a field lens FL.

The display panel DP may include a light source for displaying an image, a plurality of pixels, and a display driver for driving the plurality of pixels. Specific functions, structures, and the like of the display panel DP will be described below with reference to FIGS. 2 and 3.

The field lens FL may adjust the optical path by diffraction of the light emitted from the display panel DP. The light passing through the field lens FL may be displayed as a hologram image IM at the front end of the field lens FL.

Meanwhile, the holographic display device according to an exemplary embodiment of the present invention may display not only a hologram image IM but also a planar image. That is, the holographic display device according to an exemplary embodiment of the present invention may be driven in a first mode displaying a 3D holographic image or in a second mode displaying a 2D flat image.

The driving mode of the holographic display device may operate in the first mode or the second mode according to a user's setting, or operate in the first mode by a predetermined control signal or data signal input from the outside. You can also operate in mode.

FIG. 2 exemplarily illustrates a configuration of the display panel illustrated in FIG. 1.

Referring to FIG. 2, the display panel DP may include a backlight unit 10 and an optical modulator 20.

The backlight unit 10 may generate light and emit light. The backlight unit 10 may include a laser light source and emit laser light. Alternatively, the backlight unit 10 may include a light emitting diode (LED) light source.

The SLM 20 may include a plurality of pixels (not shown) for modulating at least one of an amplitude and a phase of light passing therethrough.

For example, each of the plurality of pixels may include a pixel electrode, a counter electrode, and a liquid crystal layer interposed between the pixel electrode and the counter electrode. The arrangement of the liquid crystals included in the liquid crystal layer may be changed by an electric field formed by the pixel electrode and the counter electrode, and at least one of an amplitude and a phase of the light passing through the liquid crystal layer may be modulated corresponding to the arrangement of the liquid crystals.

Each of the plurality of pixels may be provided with a color filter that determines a color of light passing through the liquid crystal layer. To this end, the light modulator 20 may include a color filter layer provided with a plurality of color filters.

FIG. 3 is a block diagram illustrating a configuration of the light modulator shown in FIG. 2.

Referring to FIG. 3, the optical modulator 20 may include a plurality of data lines DL1 to DLm, a plurality of gate lines GL1 to GLn, and a plurality of pixels PX.

Each of the plurality of data lines DL1 to DLm extends in the second direction DR2, and each of the plurality of gate lines GL1 to GLn crosses the second direction DR2 in the first direction DR1. Can be extended.

The optical modulator 20 may include a timing controller TC, a data driver DD, and a gate driver GD for driving the plurality of pixels PX.

The timing controller TC may receive a plurality of control signals CS and a data signal DATA from the outside of the holographic display device. The data signal DATA may include a data signal corresponding to a 2D plane image or a data signal corresponding to a 3D hologram image.

The timing controller TC may convert the data signal DATA to meet the data driver DD specification and output the converted converted data signal DATA ′ to the data driver DD.

The timing controller TC may generate the gate control signal GCS and the data control signal DCS in response to the control signal CS provided from the outside.

The gate control signal GCS may be a control signal for controlling the operation timing of the gate driver GD. The timing controller TC may output the gate control signal GCS to the gate driver GD.

The data control signal DCS may be a control signal for controlling the operation timing of the data driver DD. The timing controller TC may output the data control signal DCS to the data driver DD.

The gate driver GD may output gate signals in response to the gate control signal GCS. The gate lines GL1 to GLn may receive gate signals from the gate driver GD. The gate signals may be provided to the pixels PX through the gate lines GL1 to GLn.

The data driver DD may generate a data voltage. In detail, the data driver DD may convert the converted data signal DATA` into data voltages and output the converted data voltages to the pixels PX in response to the data control signal DCS.

4 is a diagram for explaining a correlation between pixel pitch and viewing field.

A pixel pitch may mean a distance between a pixel and a pixel. Here, the pixel pitch may mean a distance between color filters representing the same color.

As shown in FIG. 4, the width of the viewing zone (VZ) was measured at a distance of 500 mm from the optical modulator SLM, and the width of the viewing zone VZ corresponding to the pixel pitch PP was measured. Table 1].

On the other hand, in the present specification, the viewing area may mean an area in which the observer can observe a stereoscopic image, and the viewing area is comfortable when the width of the viewing area is equal to and / or similar to or larger than the distance between the both eyes of the observer (ER, EL). You can watch stereoscopic images.

PP in um Viewing Width (VZ; Unit: mm) 50 5 40 7 30 9 20 13 15 18 11.3 24 3.76 71

Referring to [Table 1], the smaller the pixel pitch PP, the larger the width of the viewing area VZ. That is, when the pixel pitch PP is small, the user can watch a high quality holographic image even if the distance between the holographic display device and the user is small.

In general, the average distance between pupils is about 65 (mm). Therefore, in order to view the hologram image at a distance of about 500 (mm) from the holographic display device, the size of the viewing area VZ must be about 65 (mm) or more, for example, the pixel pitch PP is 11.3 ( There is a need to manufacture a holographic display device smaller than um).

Hereinafter, a method of arranging color filters that can reduce the size of the pixel pitch PP will be described.

FIG. 5 is a plan view illustrating a color filter layer according to an exemplary embodiment of the present invention, and FIG. 6 is a plan view illustrating color filters arranged in the color filter group illustrated in FIG. 5.

Referring to FIG. 5, the color filter layer CFL may include a plurality of color filter groups CFG.

The plurality of color filter groups CFG may be arranged along the first direction DR1 and the second direction DR2.

In FIG. 5, a plurality of color filter groups CFG is illustrated as being arranged along the first direction DR1, but the present invention is not limited thereto. The color filter groups CFG may be arranged along the first direction DR1. The number of can be changed in various ways.

Referring to FIG. 6, each of the plurality of color filter groups CFG may include a first subgroup CFA1, a second subgroup CFA2, and a third subgroup CFA3. The first subgroup CFA1, the second subgroup CFA2, and the third subgroup CFA3 may be arranged along the second direction DR2.

The first subgroup CFA1 may include first color color filters R. FIG. The first color color filters R may be arranged along the first direction DR1. A plurality of rows including the first color color filters R arranged along the first direction DR1 may be provided. In this case, the plurality of rows may be arranged along the second direction DR2.

The second subgroup CFA2 may include second color color filters G. The second color color filters G may be arranged along the first direction DR1, and a plurality of rows including the second color color filters G arranged along the first direction DR1 may be provided. have. In this case, the plurality of rows may be arranged along the second direction DR2.

The third subgroup CFA3 may include third color color filters B. FIG. The third color color filters B may be arranged along the first direction DR1, and a plurality of rows including the third color color filters B arranged along the first direction DR1 may be provided. have. In this case, the plurality of rows may be arranged along the second direction DR2.

Referring to FIG. 6, the first color color filters R included in the first subgroup CFA1, the second color color filters G included in the second subgroup CFA2, and the third subband. The number of the third color color filters B included in the group CFA3 may be the same.

In addition, a plurality of columns formed by color filters arranged in even-numbered rows may be positioned between the plurality of columns formed by color filters arranged in odd-numbered rows.

For example, by the first color color filter (R) arranged in the first row, the second color color filter (G) arranged in the third row and the third color color filter (B) arranged in the fifth row The columns to be formed, the first color color filter R arranged in the second row, the second color filter G arranged in the fourth row, and the third color color filter B arranged in the sixth row. The rows formed by these may be alternately located.

Meanwhile, in FIG. 6, in each color filter group CFG, the first subgroup CFA1 is located on one side of the second subgroup CFA2, and the third subgroup CFA3 is the second subgroup CFA2. Although shown as located on the other side of the) is not limited to the present invention. That is, the arrangement order of the first subgroup CFA1, the second subgroup CFA2, and the third subgroup CFA3 may be changed in various ways.

7A is a plan view exemplarily illustrating a pixel structure of a holographic display device according to a comparative embodiment, and FIG. 7B is a plan view exemplarily illustrating a pixel structure of a holographic display device according to an embodiment of the present invention, and FIG. 8. Is a view for explaining a viewing area in a holographic display device according to a comparative example and an embodiment of the present invention.

7A and 7B, except that the arrangement of the color filters is different, the components of the other holographic display devices are assumed to be the same and described.

As illustrated in FIG. 7A, in the case of a general display device, the sub pixel PR emitting light in a first color (for example, red) and the sub pixel PG emitting light in a second color (for example, green). ) And sub-pixels PB emitting light in a third color (for example, blue) form one pixel, and in this case, the sub-pixels PR, PG, and PB emitting light in the first to third colors are It is arranged side by side along the first direction DR1.

When the color hologram image is implemented, the horizontal length between the subpixels emitting the same color may determine the horizontal viewing angle.

In the holographic display device having the pixel array structure as illustrated in FIG. 7A, the horizontal length between the first color sub-pixels PR positioned closest to each other in the horizontal direction may be about 11.28 (um). In this case, as shown in Fig. 8A, the viewing area is about 24 mm away from the light modulator SLM and about 750 mm away from the light modulator SLM. The viewing area can be about 35 mm in width and the viewing area can be about 47 mm away from the light modulator SLM. That is, when the distance between both observers is about 65 mm, it may be difficult to observe the stereoscopic image even at an observation distance 1 m away from the light modulator SLM.

On the other hand, in the holographic display device having the pixel arrangement structure as shown in FIG. 7B, compared to the holographic display device shown in FIG. 7A, the same color sub-pixels PG are located closest to each other in the horizontal direction. The horizontal length between them can be reduced to about 3.76 (um). In this case, as shown in FIG. 8B, the viewing area is about 71 mm away from the optical modulator SLM and about 750 mm away from the light modulator SLM. The viewing area may be about 106 mm in width, and the viewing area may be about 142 mm in distance from the light modulator SLM 1000 mm. That is, when the distance between both eyes of the observer is about 65 (mm), the stereoscopic image can be sufficiently observed even at an observation distance 500 (mm) away from the light modulator SLM. It is a figure for demonstrating a unit pixel.

As described above, the holographic display device according to an exemplary embodiment of the present invention may be driven in a first mode displaying a 3D holographic image or in a second mode displaying a 2D flat image.

When the holographic display device is driven in the second mode, the timing controller TC of the optical modulator 20 may provide a data signal corresponding to the 2D image to the data driver DD.

The data signal corresponding to the 2D image may include a data signal (eg, an RGB stripe type data signal) corresponding to the plurality of unit pixels.

Referring to FIG. 9, the plurality of pixels PX may be divided into a plurality of unit pixels UPX so that the plurality of pixels PX may receive a data signal corresponding to a 2D image and emit light.

Each unit pixel UPX is a first sub-pixel SPX1 that emits a first color, a second sub-pixel SPX2 that emits a second color, and a third sub-pixel SPX3 that emits a third color. Can be done.

The first sub-pixel SPX1 includes a plurality of pixels PX including the first color color filter R, and the second sub-pixel SPX2 includes a plurality of pixels including the second color color filter G. The pixels PX, and the third sub-pixel SPX3 may include a plurality of pixels PX including a third color color filter B. FIG. That is, the plurality of pixels PX may be gathered to form the sub pixels SPX1, SPX2, and SPX3.

The plurality of pixels PX are arranged at the same interval as that shown in FIG. 7B with a resolution of 2250 ppi (pixel per inch), and the first to third sub pixels SPX1, SPX2, and SPX3 each have nine pixels. When configured to include, the unit pixel UPX has a size of about 33.84 (um) and may have a resolution of about 750 ppi. That is, even in the second mode of displaying the 2D image, a high resolution image may be represented.

Meanwhile, in FIG. 9, a plurality of pixels including a first color color filter included in the first sub pixel SPX1 and a plurality of pixels including a second color color filter included in the second sub pixel SPX2. , And the plurality of pixels including the third color filter included in the third sub-pixel SPX3 are the same, but the present invention is not limited thereto.

Those skilled in the art will appreciate that the present invention can be embodied in other specific forms without changing the technical spirit or essential features of the present invention. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. The scope of the present invention is indicated by the scope of the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and the equivalent concept are included in the scope of the present invention. Should be interpreted.

DP: display panel
FL: field lens
10: backlight unit
20: light modulator
CFL: color filter layer

Claims (15)

A backlight unit emitting light; And
An optical modulator comprising a plurality of pixels each including any one of a first color filter, a second color filter, and a third color filter and modulating at least one of an amplitude and a phase of the light,
The plurality of pixels are arranged in a zigzag form,
The optical modulator further includes a color filter layer in which a plurality of the first color color filters, a plurality of the second color color filters, and a plurality of the third color color filters are arranged.
The color filter layer includes a plurality of color filter groups,
Each of the plurality of color filter groups may include a first subgroup in which the first color color filters are arranged, a second subgroup in which the second color color filters are arranged, and a third in which the third color color filters are arranged. Holographic display device comprising a sub group. The method of claim 1,
And the plurality of color filter groups are arranged along a first direction and the second direction crossing the first direction. The method of claim 1,
The first color color filters are arranged to form a plurality of rows in the first subgroup,
The second color color filters are arranged to form a plurality of rows in the second subgroup,
And the third color color filters are arranged to form a plurality of rows in the third subgroup. The method of claim 3,
The number of the first color color filters included in the first subgroup, the second color color filters included in the second subgroup, and the third color color filters included in the third subgroup are equal. Holographic display. The method of claim 3,
A holographic display device comprising a plurality of columns formed by color filters arranged in odd rows arranged between the plurality of columns formed by color filters arranged in even rows. The method of claim 1,
The plurality of pixels are divided into a plurality of unit pixels, each consisting of first, second, and third sub-pixels.
The first sub-pixel includes at least one pixel including the first color color filter.
The second sub-pixel includes at least one pixel including the second color filter,
The third sub pixel includes at least one pixel including the third color filter. The method of claim 6,
The holographic display device is driven in a first mode for displaying a three-dimensional image or a second mode for displaying a two-dimensional image. The method of claim 7, wherein
In the second mode, the optical modulator receives a data signal corresponding to the plurality of unit pixels from the outside. The method of claim 1,
The light of the first color is red light,
The light of the second color is green light,
And the third color light is blue light. The method of claim 1,
And a field lens provided on the light modulator. A plurality of pixels for modulating at least one of amplitude and phase of light;
A color filter layer in which a plurality of color filters included in the plurality of pixels are arranged;
A plurality of data lines connected to the plurality of pixels and supplying a data signal to the plurality of pixels; And
A plurality of gate lines connected to the plurality of pixels and supplying a gate signal to the plurality of pixels,
The color filter layer includes a plurality of color filter groups,
Each of the plurality of color filter groups may include a first subgroup in which first color color filters are arranged, a second subgroup in which second color color filters are arranged, and a third subgroup in which third color color filters are arranged. An optical modulator for a holographic display device comprising. The method of claim 11,
And the plurality of color filter groups are arranged along a first direction and the second direction crossing the first direction. The method of claim 11,
The first color color filters are arranged to form a plurality of rows in the first subgroup,
The second color color filters are arranged to form a plurality of rows in the second subgroup,
And the third color color filters are arranged to form a plurality of rows in the third subgroup. The method of claim 11,
And the first subgroup, the second subgroup, and the third subgroup are arranged along the second direction. The method of claim 13,
An optical modulator for a holographic display device, wherein a plurality of columns formed by color filters arranged in odd-numbered rows are disposed between the plurality of columns formed by color filters arranged in even-numbered rows.

Images