KR20060037651A - Three-dimensional display device - Google Patents

Abstract

The present invention relates to a three-dimensional image display device that can be easily applied to small devices by reducing the viewing distance for viewing stereoscopic images, and to minimize the color dispersion phenomenon to increase the quality and viewing freedom of stereoscopic images.

An image display unit in which pixels corresponding to the left eye image and pixels corresponding to the right eye image are formed in an arbitrary pattern; A parallax barrier disposed on any one surface of the image display unit and having light blocking units and light transmitting units for separating the left eye image and the right eye image implemented in the image display unit into a left eye direction and a right eye direction, respectively; It is arranged on one side of the parallax barrier and controls the light paths of the red (R), green (G), and blue (B) subpixels in one pixel of the image display unit to collect the R, G, and B light paths. Provided is a stereoscopic image display device including a light path controller.

Stereoscopic Image, 3D Image, Parallax Barrier, Autostereoscopy, Image Display, Optical Path Control

Description

Stereoscopic Image Display {THREE-DIMENSIONAL DISPLAY DEVICE}

1 is a partially exploded perspective view of a stereoscopic image display device according to an embodiment of the present invention.

2 is a partial cross-sectional view of a stereoscopic image display device according to an exemplary embodiment.

Figure 3 is a schematic diagram showing an embodiment configuration of a parallax barrier.

4 is a schematic diagram showing the configuration of an optical path control unit made of a VPG.

5 is a schematic diagram of a stereoscopic image display device using a parallax barrier according to the prior art.

FIG. 6 is a partial cross-sectional view of the stereoscopic image display shown in FIG. 5.

7 is a schematic diagram of another stereoscopic image display device using a parallax barrier.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stereoscopic image display device, and more particularly, to an autostereoscopy type stereoscopic image display device using a parallax barrier.                         

In general, a stereoscopic image display device is a device that provides a different image to the user's left and right eyes to feel the sense of distance and three-dimensional feeling to the user's image, the user can watch the stereoscopic image without wearing equipment such as polarized glasses Autostereoscopy devices are known.

A typical autostereoscopy device includes a parallax barrier, a lenticular lens, or a microlens array on the front of the image display unit, so that the left eye image and the right eye image implemented in the image display unit are respectively displayed. It adopts the method of spatial division in the direction and right eye direction.

In particular, the parallax barrier may be manufactured as a liquid crystal shutter using a transmissive liquid crystal display device, and in this case, the two-dimensional mode and the three-dimensional mode may be converted, and thus may be easily applied to a notebook fish (PC) or a mobile phone. .

FIG. 5 is a schematic diagram of a stereoscopic image display device according to the prior art using a parallax barrier, and FIG. 6 is a partial cross-sectional view of the stereoscopic image display device shown in FIG.

Referring to the drawing, in the image display unit 1, a set of red (R), green (G), and blue (B) subpixels 3a and 3b forms a set, and the row direction of the subpixel array ( It is repeatedly arranged along the X-axis direction of the figure. One of the left eye video signal Le and the right eye video signal Ri is input to each of the subpixels 3a and 3b, and typically, the subpixels located along the row direction of the array of subpixels ( 3) The right eye image signal Ri and the left eye image signal Le are alternately inputted to each other.

The parallax barrier 5 is composed of slit-shaped light blocking portions 7 and light transmitting portions 9 arranged long along the column direction (Y-axis direction in the drawing) of the array of subpixels. One light transmitting part 9 is correspondingly arranged for at least two sub pixels 3 among the sub pixels 3 positioned along the row direction of the sub pixels array.

By the above-described configuration, the right eye image implemented in the right eye subpixels 3a of the image display unit 1 is separated in the right eye direction of the user via the light transmitting unit 9 of the parallax barrier 5, and the image display unit The left eye image implemented in the left eye sub-pixels 3b of (1) is separated in the left eye direction of the user via the light transmitting part 9 of the parallax barrier 5. Thus, the user recognizes the image of the image display unit 1 as a stereoscopic image.

The following equations are geometric optics derived from the above-described stereoscopic image display, and for convenience, the refractive indexes of all the media are assumed to be 1. For more accurate calculations, Snell's law must be applied at each interface.

Here, r is the distance between the image display surface of the image display unit 1 and the image separation surface of the parallax barrier 5, B is the pitch of the light transmitting portion 9 of the parallax barrier 5, b is the parallax barrier The width of the light transmitting part 9 of (5), R is the viewing distance, L is the pitch of the subpixels 3a, 3b of the image display part 1, and M is located between the subpixels 3a, 3b. Width of the black layer 11, and e is an image separation distance or a binocular distance, which is usually set to 65 mm.

However, in the above-described stereoscopic image display apparatus, the image display unit 1 is composed of flat panel elements such as a liquid crystal display (LCD), a plasma display panel (PDP), and an organic light emitting display (OLED), and the parallax barrier 5 is In the case of the liquid crystal shutter, the viewing distance R at which the user can view the actual stereoscopic image is about 300 to 400 mm or more. This viewing distance is an unsuitable viewing distance when a stereoscopic image display device is applied to a small device such as a mobile phone or personal digital assistants (PDAs).

As a result, in order to secure a proper viewing distance within 300 to 400 mm in a small device, r must be reduced as much as possible. In this case, r may be defined as the distance between the image display surface of the flat panel element and the liquid crystal layer of the liquid crystal shutter. However, since the flat panel element and the liquid crystal shutter each have a glass substrate having a constant thickness, there is a certain limit to the reduction of the observation distance due to the reduction of r.

On the other hand, in order to solve the above-described problem, as shown in FIG. 7, the image display unit 13 receives a left eye image signal Le and a right eye image signal Ri in pixel units to display a left eye image and a right eye image. In addition, a method of separating the left eye image and the right eye image implemented in the image display unit 13 into the left eye direction and the right eye direction of the user through the light transmitting unit 17 of the parallax barrier 15 has been proposed. In this method, since L is a pixel pitch rather than a subpixel pitch, the observation distance is inversely proportional to this.

However, when the left eye image and the right eye image are separated in units of pixels, as shown in FIG. 7, light scattering from subpixels of R, G, and B does not collect at one location, but occurs.

As such, when the color dispersion occurs, an observer who views a stereoscopic image may feel confused because the color of the image appears to spread even if the eyes of the stereoscopic image are slightly moved from side to side. As a result, the degree of freedom of observation of the stereoscopic image may be reduced.

Therefore, the present invention is to solve the above problems, the object of the present invention is to be easily applied to small devices by reducing the viewing distance for viewing the actual stereoscopic image, and to minimize the color dispersion phenomenon, the quality and freedom of observation of the stereoscopic image It is to provide a three-dimensional image display device that can increase the.

In order to achieve the above object, the present invention,

Pixels corresponding to the left eye image and pixels corresponding to the right eye image are formed in an arbitrary pattern, and disposed on either side of the image display unit, and are provided in the image display unit by including light blocking units and light transmitting units. A parallax barrier that separates the left eye image and the right eye image into a user's left eye and right eye directions, and red (R) and green (G) disposed on one side of the parallax barrier and provided in one pixel of the image display unit. The present invention provides a stereoscopic image display device including an optical path controller for controlling an optical path of blue (B) subpixels to collect R, G, and B optical paths.

The image display unit is configured such that pixels corresponding to the left eye image and pixels corresponding to the right eye image are alternately arranged alternately along the row direction of the pixels array.

The light blocking parts and the light transmitting parts of the parallax barrier are alternately arranged alternately along the row direction of the pixels array, and one light transmitting part corresponds to at least two pixels among the pixels positioned along the row direction of the pixels array. Is placed.

The parallax barrier may include a first substrate and a second substrate, first and second electrodes formed on inner surfaces of the first and second substrates, a pair of alignment layers covering the first and second electrodes, and The liquid crystal shutter may include a liquid crystal layer injected and positioned between the pair of alignment layers, and a first polarizing plate and a second polarizing plate respectively formed on outer surfaces of the first substrate and the second substrate. At this time, any one of the first electrode and the second electrode is formed in the same pattern as the light blocking parts.

The optical element may be formed of a holographic optical element (HOE), a lenticular lens or a prism, and may be formed of a volume phase holographic diffraction grating (VTG), which is a kind of holographic optical element. .

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 and 2 are partial exploded perspective and partial cross-sectional views of a stereoscopic image display device according to an embodiment of the present invention, respectively.

Referring to the drawings, the stereoscopic image display apparatus includes an image display unit 4 and an image display unit 4 in which pixels 2a corresponding to a left eye image and pixels 2b corresponding to a right eye image are formed in an arbitrary pattern. In one embodiment, the parallax barrier 6 disposed in front of the image display unit 4 and spatially dividing the left eye image and the right eye image implemented in the image display unit 4, and either side of the parallax barrier 6 For example, an optical path disposed in front of the parallax barrier 6 and controlling an optical path of the red (R), green (G), and blue (B) subpixels 8R, 8G, and 8B constituting one pixel. And a control unit 10.

In the image display unit 4, the R, G, and B subpixels 8R, 8G, and 8B constitute one pixel and are repeatedly arranged along the row direction (the X-axis direction of the drawing) of the array of pixels. Subpixels of the same color are positioned along the column direction of the array (the Y-axis direction of the drawing). The right eye image signal and the left eye image signal are alternately inputted to each of the pixels 2a and 2b positioned along the row direction of the pixel array so that the image display unit displays the left eye image and the right eye image in units of pixels 2a and 2b. do.

As the image display unit 4, any display device developed so far may be used. For example, the image display unit 4 may be formed of any one of a cathode ray tube (CRT), a liquid crystal display (LCD), a plasma display panel (PDP), a field emission display (FED), and an organic light emitting diode (OLED). .                     

The parallax barrier 6 is formed of light blocking portions 12 and light transmitting portions 14 having a long slit shape along a column direction of the pixels array. The light transmitting parts 14 correspond to one of at least two pixels among the pixels 2a and 2b positioned along the row direction of the pixels array, and the left eye image and the right eye image implemented in the image display unit 4 are arranged. Separate the left and right eyes respectively. 1 and 2 illustrate, for example, a configuration in which one light transmitting unit 14 is correspondingly disposed for every two pixels.

As shown in FIG. 3, the parallax barrier 6 may be formed of a liquid crystal shutter 16 using a transmissive liquid crystal display device of a normally white mode.

The liquid crystal shutter 16 has a first electrode 18a and a second substrate 18b disposed to face each other, and a first electrode formed on an inner surface of the first substrate 18a and the second substrate 18b facing each other. The liquid crystal layer injected and positioned between the pair of alignment films 22 covering the 20a and the second electrodes 20b, the first electrodes 20a and the second electrodes 20b, and the pair of alignment films 22. And a first polarizing plate 26a and a second polarizing plate 26b attached to the outer surfaces of the first substrate 18a and the second substrate 18b, respectively. Any one of the first electrode 20a and the second electrode 20b, for example, the first electrode 20a may have the same pattern as the light blocking units 12 described above.

As a result, when a predetermined driving voltage is applied to the first electrode 20a and the second electrode 20b, the arrangement state of the liquid crystal molecules included in the liquid crystal layer 24 is changed at the portion where the first electrode 20a is positioned. Light is blocked, and light is transmitted at a portion where the first electrode 20a is not located. Thereby, the 1st electrode 20a functions as the light shielding part 12, and the other part functions as the light transmitting part 14. As shown in FIG.                     

When the parallax barrier 6 is constituted by the liquid crystal shutter 16, a two-dimensional image signal is input to the pixels 2a and 2b of the image display unit 4 as necessary, and the entire liquid crystal shutter 16 is It can be turned off to implement a two-dimensional mode.

Next, the optical path control unit 10 controls the optical paths of the R, G, and B subpixels 8R, 8G, and 8B constituting one pixel 2a, 2b of the image display unit 4 so that R, It collects G and B optical paths. This is to suppress the color dispersion phenomenon in which the optical path of each subpixel spreads through the parallax barrier 6 due to the positional difference between the R, G, and B subpixels 8R, 8G, and 8B. Improve quality and freedom of observation.

More specifically, the optical path controller 10 includes a holographic optical element (HOE), a lenticular lens, or a prism, and receives light having different incidence angles and wavelengths to control a path thereof so as to control an emission angle difference. Minimize.

In particular, the holographic optical device (HOE) is preferable as the optical path controller 10 because it can control the light path for each of the R, G, B wavelength bands, and can be manufactured in a thin film form. In the present exemplary embodiment, the optical path controller 10 may be formed of a volume phase holographic grating (VPG), which is one type of a holographic optical element (HOE).

4 is a schematic diagram illustrating an operation principle of an optical path controller configured of a VPG. Referring to the drawings, the VPG 28 is a configuration in which the interference pattern corresponding to the diffraction grating 32 is recorded on the photopolymer film using a laser, and the light incident on the VPG 28 is incident angle, wavelength band, and diffraction grating. Depending on the characteristics of (32), i.e., the refractive index of the diffraction grating 32, the grating period and the thickness, the amount and direction of diffraction change little by little through the VPG 28.

In consideration of the optical characteristics of the VPG 28, the VPG 28 may be used according to the subpixel width and pitch of the image display unit 4 and the distance between the image display surface of the image display unit 4 and the image separation surface of the parallax barrier 6. The optical path control unit 10 is constituted by appropriately setting optical characteristics of the "

As a result, when the optical path controller 10 is disposed in front of the parallax barrier 6, the light emitted from the R, G, and B subpixels 8R, 8G, and 8B, which constitute one pixel, is divided into positions of the subpixels. As a result, a slight difference occurs in the angle of incidence to the parallax barrier 6, but the light paths of the R subpixel 8R and the B subpixel 8B pass through the optical path control unit 10, and thus the G subpixel 8G. The light path is refracted toward to make the light path coincide.

In fact, even if the light paths of the R subpixel 8R and the B subpixel 8B are refracted by only about 1 to 3 ° with respect to the light path of the G subpixel 8G, the R, G, and B subpixels 8R, 8G, The effect of coinciding the optical path of 8B) can be seen.

1 and 2 illustrate a case where the optical path controller 10 is disposed in front of the parallax barrier 6, the optical path controller 10 is disposed between the image display unit 4 and the parallax barrier 6. It can be located at In addition, the light path controller 10 may be formed of another optical device in addition to the above-described HOE, lenticular lens and prism.

As described above, the stereoscopic image display device according to the present embodiment separates the left eye image and the right eye image implemented in pixels, thereby realizing an observation distance within 300 mm for a user to observe the actual stereoscopic image, so that the mobile phone or PDA can be realized. It can be easily applied to small devices such as In addition, the stereoscopic image display device of the present exemplary embodiment has an advantage of minimizing color dispersion and improving quality and viewing freedom of stereoscopic images.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to

As described above, the stereoscopic image display device according to the present invention can be easily applied to a small device by reducing the viewing distance for viewing the actual stereoscopic image, and minimizes the color dispersion phenomenon in which the R, G, and B optical paths are dispersed. It has the effect of improving quality and freedom of observation.

Claims (6)

An image display unit in which pixels corresponding to the left eye image and pixels corresponding to the right eye image are formed in an arbitrary pattern; A parallax barrier disposed on one surface of the image display unit and having light blocking units and light transmitting units to separate left and right eye images implemented in the image display unit in a left eye direction and a right eye direction, respectively; And The optical paths of the red, green, and blue subpixels disposed on one side of the parallax barrier and disposed in one pixel of the image display unit may be used to control the R, G, and B optical paths. Gathering optical path control Stereoscopic display device comprising a. The method of claim 1, And a pixel corresponding to the left eye image and a pixel corresponding to the right eye image are alternately arranged in the image display unit in a row direction of the array of pixels. The method of claim 1, The light blocking portions and the light transmitting portions of the parallax barrier are alternately arranged alternately along the row direction of the pixels array. And a light transmitting unit corresponding to at least two pixels among pixels positioned along a row direction of the array of pixels. The method of claim 3, The parallax barrier includes a first substrate and a second substrate, first and second electrodes formed on inner surfaces of the first and second substrates, a pair of alignment layers covering the first and second electrodes, A liquid crystal layer injected and positioned between the pair of alignment layers, and a first polarizing plate and a second polarizing plate respectively formed on outer surfaces of the first substrate and the second substrate, Any one of the first electrode and the second electrode is formed in the same pattern as the light blocking unit. The method of claim 1, And an optical element comprising one of a holographic optical element (HOE), a lenticular lens, and a prism. The method of claim 1, 3. The stereoscopic image display device of which the optical element is formed of volume phase holographic gratings (VPGs).

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