KR100826355B1 - Improvement apparatus of image quality in 3 panel type display system using diffraction modulation and method thereof - Google Patents

Abstract

The present invention is a display system using a motion diffraction type optical modulator, after receiving two or more consecutive image information input from an image codec, extracts the motion information on the screen from each image signal information and extracts the extracted motion information An apparatus and method for improving image quality in a display system using a three-panel diffraction type optical modulator to enable smooth image realization by generating and inserting intermediate images between frames by using a.

Optical modulator, diffractive optical modulator, quality improvement, intermediate image

Description

Improvement apparatus for image quality in display system using three-panel diffraction type optical modulator and method thereof

1 is a structural diagram of a reflective changeable grating light modulator according to the prior art;

Figure 2 is a cross-sectional view of the recessed thin film piezoelectric optical modulator according to the prior art.

Figure 3 is a block diagram of a display system using a three-panel diffraction type optical modulator equipped with an image quality improving apparatus according to an embodiment of the present invention.

4 is a block diagram illustrating the electromagnetic field of FIG. 3.

5 is an internal block diagram of an image quality improving apparatus according to an embodiment of the present invention.

6 is a flowchart of a method for improving image quality according to an embodiment of the present invention.

7 is a conceptual diagram illustrating a method for improving image quality according to an embodiment of the present invention.

FIG. 8 is a conceptual diagram for explaining synchronous control in the projection and scanning optics of FIG. 3 for explaining synchronous control when performing forward and backward scanning using a galvanometer mirror; FIG.

FIG. 9 is a conceptual diagram for explaining synchronous control in the projection and scanning optics of FIG. 3 for explaining synchronous control when scanning is performed using a polygon meter mirror. FIG.

<Description of the symbols for the main parts of the drawings>

501: Image buffer 502: Difference image calculation unit

503: Image motion determiner 504: Intermediate image generator

The present invention is a display system using a three-panel diffractive optical modulator, after receiving two or more consecutive image information input from an image codec, calculates motion information on the screen from each image signal information and calculates the calculated motion. The present invention relates to an apparatus and method for improving image quality in a display system using a three-panel diffraction type optical modulator for generating a smooth image by generating and inserting intermediate images between frames using information.

Recently, micromachining technology for manufacturing micro optical components such as micro mirrors, micro lenses, switches, micro inertial sensors, micro biochips, and micro wireless communication devices using semiconductor device manufacturing processes has been developed.

Here, the micro-mirror is applied in various ways depending on the up and down direction, the rotation direction, the sliding direction and the like and the dynamic and static motion. Up and down motion is applied to phase compensator or diffractometer, and tilting motion is scanner, switch, optical signal divider, optical signal attenuator, light source array, etc., and sliding direction is light shield or switch optical signal. It is applied as a dispenser.

An example of such a micro mirror is a reflective deformable grating light modulator 10 as shown in FIG. Such an optical modulator 10 is disclosed in US Pat. No. 5,311,360 to Bloom et al. The modulator 10 includes a plurality of regularly spaced deformable reflective ribbons 18 having reflective surface portions and suspended above the substrate 16. An insulating layer 11 is deposited on the silicon substrate 16. Next, deposition of the sacrificial silicon dioxide film 12 and the silicon nitride film 14 is followed.

The nitride film 14 is patterned from the ribbon 18 and a portion of the silicon dioxide layer 12 is etched so that the ribbon 18 is retained on the oxide spacer layer 12 by the nitride frame 20.

In order to modulate light having a single wavelength λ _0, the modulator is designed thick with a thickness of the oxide spacers 12 of the ribbon 18 so that the λ _0/4.

The lattice amplitude of this modulator 10, defined by the vertical distance d between the reflective surface 22 on the ribbon 18 and the reflective surface of the substrate 16, is the ribbon 18 (the ribbon 16 serving as the first electrode). Is controlled by applying a voltage between the reflective surface 22 of the substrate 16 and the substrate 16 (the conductive film 24 under the substrate 16 serving as the second electrode).

2 is a cross-sectional view of a recessed thin film piezoelectric optical modulator according to the related art.

Referring to the drawings, the recessed thin film piezoelectric optical modulator according to the related art includes a silicon substrate 201 and an element 210.

Here, the element 210 has a constant width and a plurality of constant alignment to form a recessed thin film piezoelectric optical modulator. In addition, the elements 210 have different widths and alternately arranged to form a recessed thin film piezoelectric optical modulator. In addition, the elements 210 may be spaced apart from each other at a predetermined distance (almost the same distance as the width of the elements 210), in which case the micromirror layer formed on the entire surface of the silicon substrate 201 is incident. Reflects and diffracts light.

The silicon substrate 201 has depressions to provide air space to the elements 210, an insulating layer 202 is deposited on the upper surface, and ends of the elements 210 are attached to both sides of the depressions. .

The element 210 has a rod shape, and the bottom surfaces of both ends are attached to both side regions outside the recessed portion of the silicon substrate 201 so that the center portion is spaced apart from the recessed portion of the silicon substrate 201. The portion located in the depression of the 201 includes a lower support 211 movable up and down.

In addition, the element 210 is stacked on the left end of the lower support 211, and is laminated on the lower electrode layer 112 and the lower electrode layer 212 to provide a piezoelectric voltage, and when voltage is applied to both sides, the contraction and A piezoelectric material layer 213 that expands to generate a vertical driving force, and an upper electrode layer 214 that is stacked on the piezoelectric material layer 213 and provides a piezoelectric voltage to the piezoelectric material layer 213 are included.

In addition, the element 210 is stacked on the right end of the lower support 211 and is laminated on the lower electrode layer 212 ′ and the lower electrode layer 212 ′ for providing a piezoelectric voltage. A piezoelectric material layer 213 'that contracts and expands to generate a vertical driving force, and an upper electrode layer 214' that is stacked on the piezoelectric material layer 213 'and provides a piezoelectric voltage to the piezoelectric material layer 213'. Doing.

On the other hand, the diffraction type optical modulator can have various applications, for example, it is used as a projector for a large screen, in particular as a projector of a digital image or as an image projection apparatus of a computer.

In this application, when one diffraction type optical modulator is used to implement a color image, it is called a display system using a one-panel type diffraction type optical modulator, and when a different diffraction type optical modulator is used for each color, It is called a display system using a panel diffraction type optical modulator.

It is necessary to consider in the application of the display system using the diffractive optical modulator, it is necessary to enable a smooth image.

The present invention was devised to satisfy the above needs. In a display system using a three-panel diffractive optical modulator, an image is refreshed at an interval faster than an input image period by using an intermediate image between the image and the image. An object of the present invention is to provide a device and a method for improving image quality by performing a process to enable a smooth image.

According to an aspect of the present invention, there is provided a display system using a three-panel diffraction optical modulator, comprising: an image buffer unit configured to receive and store at least two frames of images from an image input unit; And image generating means for generating and outputting an intermediate image when there is motion between frames stored in the image buffer unit.

In addition, the present invention is a display system using a three-panel diffraction type optical modulator, the image quality improving device comprising: a first step of storing at least two frames or more of the RGB image signal input from the image input unit; And a second step of generating and outputting an intermediate image when the movement occurs by determining whether the movement occurs between frames.

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

3 is a block diagram of a display system using a three-panel diffraction type optical modulator equipped with an image quality improving apparatus according to an embodiment of the present invention.

Referring to FIG. 3, a display system using a three-panel diffraction type optical modulator equipped with an image quality improving apparatus according to an embodiment of the present invention includes a display optical system 302 and a display electronic system 304.

The display optical system 302 receives light from the laser light sources 306R, 306G, and 306B of each color of red (R), green (G), and blue (B), and the light emitted from each of the laser light sources (306R, 306G, and 306B). A plurality of illumination optics 308R, 308G, and 308B, each of which illuminates the corresponding diffraction type optical modulators 310R, 310G, and 310B to produce linear light for irradiation with elliptical narrow and long line-shaped light. A plurality of diffractive light modulators 310R, 310G and 310B, which modulate the linear light irradiated from the sections 308R, 308G, and 308B to generate diffracted light, and are respectively modulated by the diffractive light modulators 310R, 310G and 310B. Sliren for separating the diffracted light of R, G, and B collected by the light collecting unit 312 and the light collecting unit 312 to collect the diffracted light and passing the diffracted light of the desired order among the separated diffraction light of different orders The diffraction light that has passed through the Schlieren optics 314 and the Schlieren optics 314 and collects the collected diffracted light in a forward and backward line scan A projection, and the scanning optical unit 316, and a display screen 318 to perform.

The display electromagnetic field 304 is connected to the laser light sources 306R, 306G, 306B, the diffractive light modulators 310R, 310G, 310B, and the projection and scanning optics 316.

A power supply unit (not shown) of the display electromagnetic field 304 provides power to the laser light sources 306R, 306G, and 306B. The laser light sources 306R, 306G, and 306B emit laser light, the cross-sectional view of the emitted laser light being circular, and the intensity profile of the light has a Gaussian distribution.

Each of the illumination optics 308R, 308G, and 308B converts the laser light emitted by each of the laser light sources 306R, 306G, and 306B into an elliptical narrow, long linear light beam, and each corresponding diffractive light modulator. It focuses on (310R, 310G, 310B).

The optical modulator driving circuit (not shown) of the display electron system 304 is applied to the diffractive optical modulators 310R, 310G, and 310B when an elliptical narrow and long linear light is incident from the illumination optical units 308R, 308G, and 308B. According to the control of the modulated linear light incident to generate the diffracted light and emits, the light collecting unit 312 condenses each light source having a plurality of orders of diffraction light and is emitted to the display screen 318 side as a single light source do.

Then, when the diffraction light having various diffraction orders is incident, the schlieren optical unit 312 selectively passes diffracted light having a desired diffraction order. The plan view of the Schlielen optical unit 312 is composed of a Fourier lens (not shown) and a spatial filter or a dichroic filter (not shown), for example. One is selected to pass the selected diffracted light.

The projection and scanning optical unit 316 is composed of a condenser lens (not shown), a scanner (not shown), and a projection lens (not shown), and the scanner is incident diffraction light under the control of the display electron system 304. Performs line scanning on the screen 318 to generate a color image. That is, the projection and scanning optics 316 are displayed on the screen 318 while scanning a line image composed of a plurality of pixels, for example, 1080 pixels, passing through a spatial filter or a dichroic filter (not shown). To generate a color image, and also in the reverse direction, unlike the prior art, a line image is displayed on the screen 318 to generate a color image.

Meanwhile, as shown in FIG. 4, the display electromagnetic field 304 may include an image input unit 400, an image quality improving apparatus 401, an image pivot unit 402, a gamma reference voltage storage unit 404, an image correction unit, and a control unit 406. And a correction data storage unit 408 for each pixel, an image data output unit 410, an image synchronization signal output unit 412, a reference voltage output unit 414, a light source switching unit 416, and a scanning control unit 418. Doing.

Here, the image input unit 400 receives image image data from the outside, and simultaneously receives a vertical synchronization signal Vsync and a horizontal synchronization signal Hsync.

The image quality improving apparatus 401 receives image information of two or more frames consecutively from the image input unit 400 and then calculates motion information on the screen from each image information, and calculates intermediate information between frames from the calculated motion information. Create an intermediate image.

In addition, the image quality improving apparatus 401 outputs an intermediate image generated between the input images received from the image input unit 400 to perform an image refresh process at a faster interval than the input image cycle, thereby enabling a smooth image.

Next, the image pivot unit 402 performs a data transpose for converting the horizontally aligned image image data in the longitudinal direction, and converts the image image data input in the lateral direction into the image image data in the vertical direction. do. The reason why the data pivot is required in the image pivot unit 402 is that in the case of the diffractive optical modulators 310R, 310G, and 310B, a plurality of pixels are arranged vertically so that they are scanned and displayed in a horizontal direction. Because.

The image correction and control unit 406 reads the gamma reference voltage stored in the gamma reference voltage storage unit 404 and outputs the gamma reference voltage to the reference voltage output unit 414 for each light source. Also, when the image image data is input from the image pivot unit 402, the image correction and control unit 406 performs correction according to the pixel-specific correction data table stored in the pixel-specific correction data storage unit 408, and corrects the image image data. Is output to the image data output unit 410.

On the other hand, the pixel-by-pixel correction data stored in the pixel-by-pixel correction data calculating unit 408 to generate the corrected output image image data by the image correction and control unit 406 corrects the image image data input from the image pivot unit 402 The above is a table for reference.

The image correction and control unit 406 outputs the vertical synchronizing signal and the horizontal synchronizing signal received from the image pivot unit 402 to the image synchronizing signal output unit 425.

In addition, the image correction and control unit 406 outputs a light source switching control signal to the light source switching unit 416, and outputs a scanning control signal to the scanning control unit 418.

Then, when the image data (gradation) is input from the image data output unit 410, and the reference voltage is input from the reference voltage output unit 414, the driving IC refers to the input reference voltage to drive the image image data. The voltage is output to the diffraction optical modulators 310R, 310G, 310B.

5 is an internal block diagram of a device for improving image quality according to an embodiment of the present invention, and FIG. 6 is a flowchart of a method for improving image quality according to an embodiment of the present invention.

Referring to the drawings, the image quality improving apparatus according to an embodiment of the present invention, the image buffer 501, the difference image calculation unit 502, the region-specific image motion determination unit 503, the intermediate image generation unit 504 Equipped.

Here, the image buffer 501 stores the RGB image signal input from the image input unit 400 for image information (for at least 2 frames) for the Nth and N + 1th frames for each RGB.

The difference image calculating unit 502 calculates a motion vector between two images by applying a temporal filter to two image frames, and calculates each of the RGB images.

Next, the image motion determination unit 503 determines whether image motion between the two images has occurred and removes the difference image due to noise by applying a threshold value to the difference image. In this case, it is determined whether the motion is generated for each region for the occurrence of the movement of the threshold value or more.

The intermediate image generator 504 generates an intermediate image between the two images based on the motion occurrence region of the threshold value or more. At this time, if necessary, the N (or N + 1) th image value is applied as it is to the region where no image motion occurs.

On the other hand, the image pivot unit 402 receives and outputs an N-th input image frame when motion does not occur in the input image, and outputs an image generated by the intermediate image generator 504 when motion occurs in the input image. Take input and output.

Now, with reference to Figures 5 and 6 will be described in detail with respect to the image quality improving apparatus and method according to an embodiment of the present invention.

First, the image buffer 501 stores the RGB image signal input from the image input unit 400 for image information (for at least 2 frames) for each of the Nth and N + 1th frames for each RGB (step S110).

Then, the image buffer 501 determines whether a movement has occurred from the RGB image signal received from the image input unit 400 (step S112).

The image buffer 501 outputs an input image to the image pivot unit 402 if no movement occurs as a result of the determination (step S114), and transmits an input image signal to the difference image calculation unit 502 if the movement occurs.

Then, the difference image calculation unit 502 calculates a motion vector between the two images by applying a temporal filter to the two image frames (step S116).

Next, the image motion determination unit 503 determines whether image motion between the two images has occurred and removes the difference image due to noise by applying a threshold value to the difference image. At this time, it is determined whether or not the motion is generated for each region with respect to the occurrence of the movement of the threshold value or more (step S118).

The intermediate image generator 504 generates an intermediate image between the two images based on the motion occurrence region of the threshold value or more (step S120). At this time, if necessary, the N (or N + 1) th image value is applied as it is to the region where no image motion occurs.

7 conceptually illustrates the above-described intermediate image generation process. Referring to FIG. 7, the image quality improving apparatus 401 compares N frames with N + 1 frames when an xHz image stream is input. When no motion is generated and the N frame video is output twice, the 2 * xHZ video stream is output, and when the motion is generated, the video stream of 2 * xHz is output by generating the intermediate video. Output

FIG. 8 is a conceptual view illustrating synchronous control in the projection and scanning optical unit of FIG. 3. FIG. 8 is a diagram for explaining synchronous control when performing forward and reverse scanning using a galvanometer mirror.

Here, the galvanometer mirror refers to a device that performs left and right scanning, and it is a forward and backward scanning means projecting an image image when scanning in the reverse direction as well as scanning in the forward direction.

Referring to the drawings, Rn, Gn, Bn signals are projected in the first forward scanning, and Rn, Gn, Bn signals are projected when there is no motion in the input image in reverse scanning, and intermediate images Rint, Gint, Bint when there is motion. Project the.

Here, Rn, Gn, and Bn are N frame video signals, and Rint, Gint, and Bint are intermediate video signals.

That is, depending on the presence or absence of motion, an N frame image is output when there is no motion, and an intermediate image is output when there is motion.

FIG. 9 is a conceptual view illustrating synchronous control in the projection and scanning optical unit of FIG. 3. FIG. 9 is a diagram for explaining synchronous control when scanning is performed using a polygon meter mirror. Here, the polygon meter mirror is difficult to perform reverse scanning unlike the galvanometer mirror.

In general, the rotation speed of the polygon meter mirror is x / m rps (m is the number of polygons) when outputting the xHz image input signal, and the rotation speed should be 2 * x / m rps or more to project the intermediate image to improve image quality. do.

In the drawing, if the rotation plane is K, K + 1, K + 2, ... K + m-1, the K plane is Rn, Gn, Bn output, and the K + 1 plane is Rn, Gn, If there is movement of Bn, the middle image Rint, Gint, and Bint should be output.

As described above, according to the present invention, in a display system using a three-panel diffraction type optical modulator, a smooth image is realized by performing an image refresh process at an interval faster than an input image period by using an intermediate image between the image and the image. Make this possible.

Claims (6)

An image input unit for receiving image image data and a synchronization signal from an external source, an image pivot unit for transposing and outputting an image image received from the image input unit from a horizontal arrangement to a longitudinal arrangement, and a data transformer from the image pivot unit A display system using a three-panel diffraction type optical modulator comprising a driving integrated circuit which receives a paused image image data and generates and outputs a driving signal. An image buffer unit for receiving and storing at least two frames of images from the image input unit; And And image generating means for generating an intermediate image and outputting the intermediate image to the image pivot unit if there is a movement between frames stored in the image buffer unit. The method of claim 1, And an image received by the image buffer unit from the image input unit is 10 to 15 frames per second. The method according to claim 1 or 2, The image generating means, A difference image calculator for calculating a motion vector between two images by applying a temporal filter to at least two image frames; An image motion determination unit for detecting a motion by determining whether image motion has occurred in at least two image frames; And And an intermediate image generating unit generating and outputting an intermediate image between two frames according to the result determined by the image motion determining unit. An image input unit for receiving image image data and a synchronization signal from an external source, an image buffer unit for receiving and storing at least two frames of images from the image input unit, and generating an intermediate image if there is motion between frames stored in the image buffer unit An image generating unit for outputting, an image pivot unit for transposing and outputting the image image input from the image input unit and the image generating unit from a horizontal arrangement to a longitudinal arrangement, and an image transposed data from the image pivot unit In a display system using a three-panel diffraction type optical modulator comprising a driving integrated circuit for receiving the image data to generate and output a drive signal,  A first step of storing, by the image buffer unit, at least two frames of an RGB image signal input from the image input unit; And And a second step of generating an intermediate image and outputting the intermediate image to the image pivot unit when the movement occurs by determining whether a motion occurs between frames stored in the image buffer unit. The method of claim 4, wherein The second step, The image generating means may include: 2-1 determining whether motion between frames is generated; A second step of calculating a motion vector between the two images by applying a temporal filter to the two image frames when the motion occurs as a result of the determination of the step 2-1; And And the image generating means includes generating a middle image between the images and outputting the intermediate image. The method of claim 5, wherein The second step is, Determining, by the image generating means, whether image movement between two images has occurred; Judging whether or not the motion is generated for each area with respect to the occurrence of the motion equal to or greater than a threshold as a result of the determination; And And the image generating means generates and outputs an intermediate image between the two images based on the motion generation region.

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