KR100622556B1 - Depth enhanced three-dimensional display apparatus using optical path control - Google Patents

Abstract

The present invention relates to a stereoscopic display system with improved depth through optical path control. In this stereoscopic display system, the image display unit provides a basic image, and the image display unit located on the same axis as the image providing unit displays an image provided by the image providing unit. The optical path controller gives two optical paths and two polarization states to the image displayed by the image display unit, and the polarization shutter is located on the same axis as the optical path controller, and the two optical states alternately repeat the optical path controllers. Alternately passes through the images imparted by the two polarization states. The lens array is positioned on the same axis as the polarization shutter, and aggregates the images passed by the polarization shutter to display corresponding stereoscopic images. According to the present invention, an image having an improved depth can be provided by controlling an optical path in an IP type 3D display system. In addition, since the device for controlling the optical path is used in the form of being inserted between the device for displaying an image and the lens array, it does not increase the size of the overall system and there is also no mechanical movement.

Stereoscopic Display, Light Path Controller, Light Splitter, Polarizer, Polarization Shutter, Lens Array, Center Image Plane

Description

Stereoscopic display system with enhanced depth through optical path control {DEPTH ENHANCED THREE-DIMENSIONAL DISPLAY APPARATUS USING OPTICAL PATH CONTROL}

1 is a basic conceptual diagram of an IP for a general stereoscopic display.

FIG. 2 is a diagram illustrating a reproduction principle of a general IP, and the principle of reproducing an image in the IP scheme is shown in more detail.

3 is a diagram illustrating a structure of an IP system for displaying a conventional video in three dimensions.

4 is a diagram illustrating a relationship of a general lens formula.

5 is a diagram illustrating a conceptual structure of a three-dimensional display system with improved depth through optical path control according to an embodiment of the present invention.

6A and 6B illustrate a principle of stereoscopic image reproduction in a stereoscopic display system having improved depth through optical path control according to an exemplary embodiment of the present invention.

7A and 7B illustrate a principle of stereoscopic image reproduction in a stereoscopic display system having improved depth through optical path control according to another exemplary embodiment of the present invention.

The present invention relates to a stereoscopic display system, and more particularly, to a stereoscopic display system with improved depth through optical path control.

In general, the IP (Integral Photography) method using a lens array among 3D image realization techniques has been gradually improved since it was first proposed by Lippmann in 1908. Due to the lack of attention, recent research has been actively conducted with the development of high resolution photographing devices and high resolution display devices.

1 is a basic conceptual diagram of an IP for a general stereoscopic display.

As shown in FIG. 1, in the IP system, the entire system is largely composed of two functional units, that is, a photographing unit and a display unit.

The photographing unit stores a basic image in various directions of the three-dimensional object 110 generated by the elementary lenses constituting the first lens array 120 in the photographing (imaging) device 130.

The display unit is a reverse process of the photographing unit, and displays the stored base images by the display device 140, and the base images are combined while passing through the second lens array 150, and then the 3D image is located at the position where the original 3D object was located. Play at 160.

FIG. 2 is a diagram illustrating a reproduction principle of a general IP, and the principle of reproducing an image in the IP scheme is shown in more detail.

As shown in FIG. 2, when the base images are displayed on the display device 240, the base images are condensed into the integrated image 220 through the respective base lenses 230. Will be observed.

Therefore, the depth of the integrated image 220 displayed according to the change of the interval of the base image is adjusted to be able to create a three-dimensional stereoscopic image.

However, in the conventional IP system, since motion picture film has been used as a photographing device and a display device, moving picture is not possible, but recently, a moving picture is also displayed three-dimensionally by using a charge coupled device (CCD) camera and a display device. I can do it.

On the other hand, Figure 3 is a diagram showing the structure of an IP system for displaying a conventional video in three dimensions.

As shown in FIG. 3, a structure of an IP system for displaying a conventional moving image in three dimensions is illustrated. The CCD camera 340 is used as a photographing apparatus, and as a display apparatus, for example, an LCD (liquid crystal). device) It is possible to display a 3D video by the method using the panel 350. Here, reference numeral 330 denotes a convex lens.

While the stereoscopic display system using the IP method has an advantage of viewing the 3D image 310 at various points of view without special glasses, the area where the stereoscopic image 370 is well displayed is the second lens array 360. Since it is a relatively narrow area before and after the center image plane determined by the distance between the image display device 350 and the image display device 350, there is a disadvantage that the depth of the stereoscopic image that is substantially displayed may be limited.

 Accordingly, the technical problem of the present invention is to solve the above problems, to provide a three-dimensional display system with improved depth through the optical path control capable of displaying a relatively large depth while enabling a three-dimensional display by IP method It is for.

A stereoscopic display system according to one feature of the present invention for achieving the above object,

As an IP (Integral Photography) stereoscopic display system,

An image providing unit providing a basic image; An image display unit which displays the base image; An optical path controller positioned on the same axis as the image display unit and providing two optical paths and two polarization states to the image displayed by the image display unit; A polarization shutter positioned on the same axis as the optical path controller and alternately repeating the two polarization states to alternately pass an image imparted by the optical path controller to the two polarization states; And a lens array positioned on the same axis as the polarization shutter and displaying a corresponding stereoscopic image by aggregating an image passed by the polarization shutter.

Here, the lens array is characterized by displaying the image having two optical paths on two different central image planes by the optical path controller.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention. Like parts are designated by like reference numerals throughout the specification.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to the three-dimensional display system with improved depth through the optical path control according to an embodiment of the present invention.

In general, in the case of an IP-based stereoscopic display system, a limitation in expressing the sense of depth is that individual lenses of the lens array used to aggregate stereoscopic images have a constant focal plane parallel to the lens array plane. For example, diffraction occurs in an image that is out of the center image plane formed of a set of focal planes.

Therefore, when displaying a stereoscopic image having a large depth of sense before and after the center image plane using the IP-type stereoscopic display system, the more the deviation from the center image plane, the displayed image is distorted, thereby creating a limitation in depth that can be expressed. In the conventional IP-based stereoscopic display system, it is difficult to express a stereoscopic image having a large depth.

Meanwhile, the position of the central image plane is determined by the distance between the lens array and the image display means and the focal lengths of the individual lenses of the lens array. Lens formulas that determine their relationship are shown in FIG. 4.

4 is a diagram showing a relationship between a general lens formula, in which a represents a distance between the image display means 410 which is a light source and the lens array 420, and b is between the lens array 420 and the central image plane 430 Indicates the distance of. In this case, the center image plane 430 corresponds to the focal plane of the lens array 420.

Here, the focal length f of the lens array 420 has a relationship of f = ab / (a + b), and when the focal length f is a fixed value, a relationship is inversely proportional to b. .

As can be seen in FIG. 4, if the focal length f of the lens array 420 is fixed, the central image plane becomes larger as the distance a between the lens array 420 and the image display means 410 increases. 430 becomes closer to the lens array 420, and as the distance a between the lens array 420 and the image display means 410 gets closer, the center image plane 430 is farther from the lens array 420. You lose.

In other words, by changing the distance a between the lens array 420 and the image display means 410, the distance b between the center image plane 430 and the lens array 420 may also be changed.

In this embodiment of the present invention, the optical path controller is used to optically control the distance between the lens array 420 and the image display means 410. Thus, an IP method having an existing fixed single center image plane is used. Can be implemented as an IP type display system having two central image planes.

As described above, the IP system having two central image planes has a wider area for displaying images with less distortion in the lens axis direction, so that stereoscopic images having a greater depth can be easily displayed.

5 is a diagram illustrating a conceptual structure of a three-dimensional display system with improved depth through optical path control according to an embodiment of the present invention.

As shown in FIG. 5, the stereoscopic display system having improved depth through the optical path control according to an embodiment of the present invention includes an image providing unit 510 for providing a basic image and a basic provided by the image providing unit 510. An image display unit 520 for displaying an image, an optical path controller 530 sequentially positioned on the same axis as the image display unit 520, and a polarization shutter sequentially positioned on the same axis with the optical path controller 530. 540, and a lens array 550 sequentially positioned on the same axis as the polarization shutter 540.

The image providing unit 510 may be, for example, a lens for forming an image of a subject in a general photographing system; A photographing element for outputting an electrical signal for an image of a subject formed by a lens; And a signal processing unit which processes an electrical signal output from the photographing device (noise removal, signal amplification, etc.) to form a basic image, and also calculates and generates a basic image based on the input information. It may be.

The image display unit 520 displays a basic image generated by the image provider 510 and displays an image using a display device such as an LCD or a cathode-ray tube (CRT). The image display unit 520 Since a technique for displaying an image is already known, a detailed description thereof will be omitted.

The optical path controller 530 is composed of a plurality of light splitters 532 formed of a 1 × N matrix and 2N polarizers 534 and 536.

Each light splitter 532 has a rectangular shape, and forms an angle of 45 ° with the lens array 550 as shown in FIG. 5, and provides two optical paths to the base image displayed on the image display unit 520. Will be Specifically, a path through which the basic image displayed by the image display unit 520 is directly passed to the polarization shutter 540 through the polarizer 534, and the foundation reflected by the neighboring optical splitter 532 and returned through the polarizer 536. The image is reflected to have two optical paths that pass through the polarizer 534 to the polarization shutter 540.

Here, the sizes of the individual light splitters 532 are appropriately determined according to the optical path difference to be provided, and the individual polarizers 534 and 536 also have a rectangular shape, the size of which depends on the size of the light splitter 532. Is determined.

N polarizers 536 of the polarizers 534, 536 are positioned between the respective light splitters 532 and placed at an angle of 90 ° with the lens array 550. In this case, each polarizer 536 alternately has polarization states orthogonal to each other that are the same as the two polarization states of the polarization shutter 540. In FIG. 5, an example of a polarization state that s-polarizes and p-polarizations are orthogonal As presented.

The remaining N polarizers 534 are placed between each of the light splitters 532 in parallel with the lens array 550, which are also two polarization states of the polarization shutter 540, namely s-polarized state, p-polarized light. Alternately have polarization states orthogonal to each other that are the same as states. At this time, an example of the order of the polarization states of the polarizers 534 is as shown in FIG. Here, the polarizer 534 gives different polarization states to the base image having the two optical paths by the light splitter 532. In this case, two polarizers 534 and 536 are positioned to correspond to each of the light splitters 532, and the two polarizers 534 and 536 have the same polarization state.

Meanwhile, the polarization shutter 540 alternately passes the light of the polarization state orthogonal to each other by the polarizers 534 and 536 after being displayed by the image display unit 520, and the image display unit 520 and the light path controller 530. Or between the optical path controller 530 and the lens array 550 or between the lens array 550 and the observer 560. In the exemplary embodiment of the present invention, the light path controller 530 is disposed between the lens array 550 as an example. The operation speed of the polarization shutter 540 is fast enough to cause an afterimage effect on the human eye, and operates in synchronization with the image providing unit 510.

The lens array 550 may be formed of a plurality of convex lenses, Fresnel lenses, or lenses of various shapes, depending on the application, in a matrix of M × N (where N = M or N ≠ M).

The operation of the stereoscopic display system with improved depth through the optical path control according to the embodiment of the present invention having such a structure will be described in more detail.

First, the image provider 510 alternately generates a base image of two center image planes by photographing or calculation and provides the image to the image display unit 520, and the image display unit 520 displays the base image.

Next, the optical path controller 530 passes the basic image displayed by the image display unit 520 through the two optical paths, and gives polarization states.

Next, the polarization shutter 540 selectively passes only one polarization state among the base images passed through the optical path controller 530, and the base image passed through the polarization shutter 540 is moved by the lens array 550. In turn, the stereoscopic image is displayed on two central image planes alternately.

6A and 6B illustrate a principle of stereoscopic image reproduction in a stereoscopic display system having improved depth through optical path control according to an exemplary embodiment of the present invention.

6A and 6B, the basic image displayed by the image display unit 520 may include a path directly passing through the individual light splitter 532 of the optical path controller 530 and a neighboring individual light splitter 532. After being reflected, the light beam passes through the polarizer 536 and is reflected by its light splitter 532 and then passes through the polarizer 534. In the case of the latter path, since the basic image may be covered by the thickness of the individual light splitter 532, there may be a loss of image information. Therefore, the thickness of the individual light splitter 532 is preferably as thin as possible.

Meanwhile, the individual polarizers 534 and 536 impart a polarization state to the base image, such that the base image having the polarization states that are alternately orthogonal to each other in each of the individual light splitters 532 passes. This is controlled by the polarization shutter 540.

Next, the base image immediately passing through the optical path controller 530 is collected by the lens array 550 to display a stereoscopic image with a sense of depth in the vicinity of the center image plane A, which is a constant distance from the lens array 550. On the contrary, the base image reflected and passed between the individual light splitters 532 of the light path controller 530 has the effect of increasing the light path by a distance reflected by the base image which has passed directly through the light path controller 530. According to the relationship described with reference to FIG. 4, the stereoscopic image is displayed with a sense of depth in the vicinity of the center image plane B closer to the lens array 550 than the center image plane A. FIG.

6A and 6B illustrate in detail the principle of reproducing portions of a stereoscopic image according to different polarization states of the polarization shutter 540, respectively.

The polarization shutter 540 selectively passes only one polarization state among the images having polarization states orthogonal to each other passing through the light path controller 530, and thus, individual light of the light path controller 530 in one polarization state. Only the images passed between one by one of the dividers 532 are passed. At this time, the images passed by one polarization state of the polarization shutter 540 are collected by the lens array 550 to display corresponding portions of the two central image planes.

As described above, the polarization shutter 540 alternately changes the two polarization states of FIGS. 6A and 6B to simultaneously display complete image information on the two central image planes A and B using the afterimage effect.

In addition, since the base image should be provided differently for different polarization states of the polarization shutter 540, the image provider 510 should provide a base image suitable for the polarization state in synchronization with the polarization shutter 540. The portion of the basic image that passes immediately through the optical path controller 530 should display information corresponding to the center image plane A, and the portion that passes after being reflected between the individual light splitters 532 of the optical path controller 530. Should display information corresponding to the center image plane B.

에 해당하도록 제시되어 있으나, 이 길이는 중심 영상 평면 A와 B의 상대적인 거리 차이에 영향을 미치는 요소로서, 필요에 따라 적절한 길이로 조정될 수 있다. On the other hand, the length of the individual light splitters 532, i.e., the length of the individual light splitters 532 in the direction of 45 ° with the lens array surface, is determined by the diameter x of the individual lenses of the lens array 5.

Although it is proposed to correspond to this length, this length is an factor that affects the relative distance difference between the center image planes A and B, and can be adjusted to an appropriate length as necessary.

In addition, since the amount of light decreases by 1/2 every time the basic image passes through the light splitter 532 and the polarizers 534 and 536, the light splitter 532 and the polarizer 534 may be used to compensate for this. , 536 may be replaced with a polarization beam splitter. Here, the polarized light splitter is a device that gives a different polarization state according to each path while changing the path of the input light.

7A and 7B illustrate a principle of stereoscopic image reproduction in a stereoscopic display system having improved depth through optical path control according to another exemplary embodiment of the present invention. Here, components having the same functions as in FIGS. 6A and 6B will be described using the same reference numerals.

As shown in FIGS. 7A and 7B, when a plurality of polarized light splitters 600 formed of a matrix of 1 × N are placed between the image display unit 520 and the polarization shutter 540, the present invention is illustrated in FIG. 5. An optical path controller 600 can be made that can serve similar to the optical path controller 530 described with reference to FIG. 6B. In this case, since the amount of light is reduced to 1/2 only when the base image first meets the polarized light splitter 600, the gain in terms of light efficiency can be obtained.

In addition, unlike in FIGS. 6A and 6B, the polarization states of the basic images passing through the individual polarized light splitters 600 are not different from one another with respect to the individual polarized light splitter 600, but instead of the individual polarized light splitters 600. It is different for each basic image reflected and passed between the basic image passing through the individual polarized light splitter 600 and the polarization shutter 540 has polarization states orthogonal to each other passing through the polarized light splitter 600. Selectively pass only one polarization state, and thus, in one polarization state, for example, in the polarization state as shown in FIG. 7A, only the basic images that are reflected and passed between the individual polarization light splitters 600 pass through the lens array. Collected by 550, the corresponding image may be completely represented in the center image plane B. FIG. In addition, in the polarization state as shown in FIG. 7A, only the basic images passing through the individual polarized light splitters 600 directly may be collected and then collected by the lens array 550 to completely express the corresponding image on the center image plane A. FIG. Therefore, the manner in which the base image is made and provided by the image providing unit 510 should also be different from those in FIGS. 6A and 6B.

Although the preferred embodiment of the present invention has been described in detail above, the present invention is not limited thereto, and various other changes and modifications are possible.

According to the present invention, an image having an improved depth can be provided by controlling an optical path in an IP type 3D display system.

In addition, since the device for controlling the optical path is used in the form of being inserted between the device for displaying an image and the lens array, it does not increase the size of the overall system and there is also no mechanical movement.

Claims (11)

In the IP (Integral Photography) stereoscopic display system, An image providing unit providing a basic image; An image display unit which displays the base image; Located on the same axis as the image display unit, to impart a first polarization state to the image displayed by the image display unit and output through the first optical path, to impart a second polarization state to the displayed image and to a second view An optical path controller for outputting through the furnace; Located on the same axis as the optical path controller, alternately repeating the first and second polarization states to alternately pass each image provided by the optical path controller through the first optical path and the second optical path. A polarizing shutter; And A lens array positioned on the same axis as the polarization shutter and configured to collect images on the first and second optical paths passed by the polarization shutter and display them on different central image planes, respectively. Stereoscopic display system comprising a. delete The method of claim 1, And wherein the two different central image planes have different distances from the lens array. The method of claim 1, And the image providing unit provides a basic image suitable for the polarization state of the polarization shutter in synchronization with the polarization shutter. The method of claim 1, The optical path controller, At least one light splitter configured to pass or reflect the base image displayed on the image display unit to impart two light paths; At least one first polarizer which imparts a polarization state to the base image reflected by the light splitter; And At least one second polarizer which imparts the same polarization state as the first polarizer with respect to the base image passing through the light splitter and the base image reflected by the light splitter Stereoscopic display system comprising a. The method of claim 5, The first polarizer, the second polarizer, and the light splitter are positioned to correspond to each lens of the lens array, and the first polarizer and the second polarizer have polarization states orthogonal to each other that are the same as two polarization states of the polarization shutter. 3D display system, characterized in that the light splitter having an alternate. The method of claim 5, The first polarizer and the second polarizer is a rectangular shape, The first polarizer is positioned between the light splitters to form an angle of 90 ° with the lens array, And the second polarizer is positioned between the light splitters so as to be parallel to the lens array. The method of claim 6, Wherein the two polarization states are s-polarized light and p-polarized light. The method of claim 5, The size of the light splitter is adjustable according to the distance between the two different central image planes. The method of claim 5, And the light splitter has a rectangular shape and is positioned at an angle of 45 ° with the lens array. The method of claim 1, The optical path controller, And a polarization light splitter configured to provide two optical paths to the base image displayed by the image display unit, and to impart different polarization states to the base image having different optical paths.

Images