KR0173705B1 - Asymmetric Screen Correction Device of Projection Image Display System - Google Patents

Abstract

The present invention relates to an asymmetric screen correction apparatus of a projection type image display system, wherein a correction mode and a correction amount are set corresponding to an image projection angle of a projection lens with respect to the screen 20, so that an image signal in the image correction direction opposite to the projection angle is set. Correction control means (40, 50, 60, 70) for generating a sampling signal of the image; image correction means (80, 90, 100, 110) for sampling the projected image signal by a sampling signal generated under the control of the correction control means; Arithmetic and control means 120 for inserting and correcting black data with respect to the image signal in the image correction direction sampled by the image correction means, and around the image signal by the image data corrected by the image correction means. Image correction processing means (130,140,150) for further processing black data to apply an image signal presented in the image correction direction opposite to the projection angle to the pixel driving means; Is equipped configuration, it is a projection angle of the image up or if it is installed in the projection type image display system to maintain the downward inclination angle to enable the projection of a normal screen display station corrects the asymmetry by the upward or downward inclination angle.

Description

Asymmetric Screen Correction Device of Projection Image Table System

1 (a) and (b) are diagrams for explaining a process of projecting an asymmetric screen of a projection table system;

FIG. 2 is a diagram showing an asymmetric screen of the projection type table system described in FIG.

3 is a block diagram showing an asymmetric screen correction apparatus of a projection image display system according to the present invention;

4 (a) and 4 (b) illustrate changes in oscillation frequency (sampling frequency) applied to up- and down-correction by the asymmetric screen correction apparatus of the projection type image display system shown in FIG. drawing,

5 (a) to (h) are exemplary views showing a process for correcting an asymmetric screen of the projection type image display system according to the present invention.

* Explanation of symbols for the main parts of the drawings

10: Projection type image display system (projector)

20: Screen 40: Calibration mode setting section

40a: upward slope correction key 40b: downward slope correction key

50: control unit 60: integral circuit unit

70: oscillation unit 80: data conversion unit (ADC)

90: first frame memory 100: horizontal sync signal separator

110: counter 120: operation control unit

130: buffer 140: second frame memory

150: image signal processing unit

The present invention relates to an asymmetric screen correction apparatus of a projection type image display system. More specifically, the sampling frequency of an image signal is varied by asymmetrical phenomenon that the upper and lower sides of the screen are asymmetrical depending on the inclination angle at which the projection type image display system is installed. The present invention relates to an asymmetric screen correction apparatus of a projection type image display system which allows a normal screen to be projected.

In general, an image display system for displaying color images is roughly divided into a direct view image display system represented by a CRT apparatus and a projection image display system represented by an LCD apparatus.

The image display system constituted by such a CRT apparatus and an LCD apparatus is difficult to enlarge a color image because the CRT apparatus or LCD apparatus which reproduces a color image is manufactured to a limited dimension.

In view of such a point, the color image signal is currently separated into light of the R, G, and B signals, and the separated R, G, and B signals are optically adjusted based on the color signal components of the color image. The projection type image display system called "projector" which displays on a comparatively large screen in a state enlarged by and constitutes a large screen is put into practical use.

By the way, according to such a projection type image display system, as shown in FIG. 1A, the center of the image projected on the screen 20 in the projection lens 10a of the projection type image display system 10 (hereinafter referred to as a projector) When the axes 30 are generally matched in the horizontal direction and coincide with each other, the projection distances l1 and l2 between the upper and lower sides of the image are equalized from the center axis 30 of the screen, and the image shown in FIG. A normal image of the shape is projected onto the screen 20.

However, when the projection lens 10a of the projector 10 is installed at a constant inclination angle with respect to the screen 20, as shown in FIG. 1 (b), on the screen 20 of the projector 10 The projected image is asymmetrical from the upper side and the lower side from the central axis 30.

That is, for example, when the projector 10 is installed to maintain an upward inclination angle with respect to the screen 20, the image projected from the projector 10 onto the screen 20 is upper and lower with respect to the central axis 30 thereof. Projection distances l1 and l2 are different from each other, and as a result, the image projected on the screen 20 becomes an asymmetric screen on an inverted rhombus shape as shown in FIG. 2 (b), and the projector 10 When installed so as to maintain a downward inclination angle with respect to the screen 20, the image becomes asymmetrical form in which the lower side is extended rather than the upper side in a rhombus shape.

Therefore, when the projector 10 is installed at an upward or downward inclination angle with respect to the screen 20, it is necessary to correct the asymmetric screen projected on the screen 20 in order to improve the viewing efficiency.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and when an image projected on a projection lens is installed to maintain an upward or downward inclination angle with respect to a screen, an inverse correction signal of an asymmetric screen projected corresponding to the upward or downward inclination angle thereof It is an object of the present invention to provide an asymmetric screen correction apparatus of a projection type image display system in which a normal screen is projected on a screen by creating and presenting a.

In order to achieve the above object, according to a preferred embodiment of the present invention, a color driving means for displaying a color image signal for an image signal, and a color image mediating the projection lens for a pixel driven by the pixel driving means. In a projection type image display system having a pixel driving panel for projecting onto a screen, a correction mode and a correction amount are set corresponding to the image projection angle of the projection lens with respect to the screen, so that the image signal in the image correction direction opposite to the projection angle is set. Correction control means for generating a sampling signal of the signal, chemical conversion correction means for sampling the projected image signal by a sampling signal generated under the control of the correction control means, and an image in the image correction direction sampled by the image correction means. Arithmetic control means for inserting and correcting black (or blacking) data for the signal, and the image correction number The asymmetric screen correction device of the projection type image display system configured to line the corrected image signal to the image correction in the reverse direction and equipped with means for applying image correction to the pixel driving unit is provided by the image data corrected by the.

Preferably, according to the present invention, the correction control means includes a correction mode setting unit for setting the image correction mode for the image perspective angle and setting the correction amount corresponding to the projection angle under the image correction mode, and setting the correction mode thereof. A control unit for generating a control signal corresponding to the correction amount set by the unit, an integrating circuit unit for generating a voltage signal by integrating the control signal provided from the control unit, and an oscillating unit for generating a sampling frequency determined by the voltage signal generated by the integrating circuit unit. The correction mode setting unit includes an upward slope correction key for adjusting the amount of correction during upward projection and a downward slope correction key for adjusting the amount of correction during downward projection.

An analog-digital conversion unit for sampling the image correction means in horizontal line units based on the sampling frequency in an image correction direction opposite to the projection angle with respect to the projected image signal, and a sampled image signal stored therein. And a counter for resetting by the image signal and counting the sampling frequency to determine the amount of blistering (or blacking) data to be added to the sampled line unit and to the periphery of the image signal.

The image correction processing means includes: a second frame memory in which the black data is added to the sampled image data applied through the buffer and the buffer in which the sampled image data and the black data are buffered, and the corrected image data is stored. And an image processor for analog-processing the image data and the black data stored in the second frame memory to generate a pixel driving signal for projecting on the screen.

The control means may generate a control signal for gradually extending a sampling area of an image signal from a first horizontal scan line to an Nth horizontal scan line when the upward tilt correction mode is set, and correct the downward tilt. When the mode is set, a control signal is generated to gradually reduce the sampling area of the image signal from the first horizontal scan line to the Nth horizontal scan line.

The black data generated by the arithmetic control means reduces the amount of data added from the first horizontal scan line gradually expanded when the upward tilt correction mode is set to the Nth horizontal scan line, The amount of data added from the first horizontal scan line which is gradually reduced in setting to the Nth horizontal scan line is increased.

Therefore, according to the asymmetric screen correction apparatus of the projection type image display system according to the present invention, when the upward or downward tilt correction mode is set by the correction mode setting means, the image correction means is generated by the sampling frequency signal generated by the correction control means. By controlling the sampling period of the image signal in the reverse direction to the projection angle of the image signal, the image signal projected by the operation control means is reversely corrected, and the black (or blacking) data generated by the operation control means is corrected by the image correction processing means. The pixel drive signal is generated in addition to the periphery of the image signal, so that the normal image signal is projected on the screen when the actual image signal is projected.

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

3 is a block diagram of the asymmetric image correcting apparatus of the projection image display system according to the present invention, and reference numeral 40 denotes a projection image display system (hereinafter referred to as a projector) while constructing correction control means in the present invention. As a correction mode setting unit for setting a correction mode for an asymmetric screen projected when the projector is installed on the control panel of FIG. 10 and the projector is installed to maintain an upward or downward inclination angle with respect to the screen (20 in FIG. 1). And an upward slope correction key 40a for setting an upward slope correction mode when the projector is inclined upward and a downward slope correction key 40b for setting down slope correction modes when the projector is inclined downward. do.

Here, the upward slope correction key 40a and the downward slope correction key 40b are configured to generate a signal for determining the amount of correction of the image signal in accordance with the number of operations.

50, 60, and 70, in the present invention constitute a correction control means for generating a sampling frequency of the image signal based on the upward slope or downward slope correction amount set by the correction mode setting unit 40, the control unit indicated by 50 is A control signal for controlling the sampling frequency is generated by the number of operation of the upward slope correction key 40a and the downward slope correction key 40b of the correction mode setting means 40. The control signal provided by the controller 50 is integrated to obtain a voltage signal, and the oscillator indicated by 70 is controlled by the voltage signal provided by the integrating circuit unit 60 to generate a sampling frequency signal.

Further, 80, 90, 100, and 110 are analog-digital conversion units and first frames constituting image correction means for performing sampling in the image correction direction opposite to the projection angle with respect to the image signal by the sampling frequency signal in the present invention. A memory, a horizontal synchronous signal separator, and a counter, among which an analog-digital converter 80 samples an image signal based on the sampling frequency signal and digitally converts the first frame memory 90. The sampled image data is stored. The horizontal synchronous signal separator 100 extracts a horizontal synchronous signal from the image signal, and the counter 110 is reset by the horizontal synchronous signal separated from the horizontal synchronous signal separator 100. The sampling frequency signal CK is counted to detect the number of data sampled in each horizontal scan line.

120 denotes an arithmetic control unit as means for inserting and correcting black (or blacking data) with respect to the sampled image correction direction image signal, and the arithmetic control unit 120 is provided to the counter 110 of the image correction means. The black (or blanking) data of the corresponding horizontal scan line is generated on the basis of the number of sampled data in each horizontal scan line detected. In addition, the operation control unit 120 generates a control signal RD for reading image data stored in the first frame memory 90, and also generates the black data BD and the control signal CT. Done.

130, 140, and 150 denote a buffer, a second frame memory, and an image signal processing unit constituting the image correction processing unit in the present invention, and the buffer 130 includes the first frame memory (under the control of the operation control unit 120). Image data read in step 90 and black data BD applied along with the control signal CT from the operation control unit 120 are applied to the operation control unit 120 for each horizontal scan line of the corrected image signal. Buffered in a form in which black data is added, and image data including black data buffered in the buffer 130 is stored in the second frame memory 140, and 150 is stored in the second frame memory 140. And an image signal processing unit for generating the signal as a signal for pixel driving so that the corrected image data stored in 140 is projected on the screen 20 by analog conversion processing.

Next, the operation of the asymmetric screen correction apparatus of the projection type image display system according to the present invention configured as described above will be described in detail with reference to FIG. 4 and FIG.

First, when the projector is arranged to maintain an upward inclination angle with respect to the screen 20, when the upward tilt correction key 40a of the correction mode setting unit 40 is operated, the controller 50 tilts the upward slope. A control signal corresponding to the number of operations of the correction key 40a is generated and applied to the integrating circuit unit 60. That is, when the upward tilt correction mode is set, the control unit 50 adjusts the image correction direction from the first horizontal scan line to the Nth horizontal scan line as shown in FIG. 4 (a). A control signal is generated to control the sampling frequency signal to be generated at a high frequency (or a form in which the sampling period is gradually reduced) gradually along the signal and the actual projection direction. In addition, the control signal generated by the controller 50 includes a control to adjust the correction amount (see 'A' in FIG. 4 (a)) in response to the number of operations of the upward projection correction key 40a. .

The control signal is integrated in the integrating circuit section 60 to obtain a voltage signal (preferably a PWM voltage signal), and the voltage signal is applied to the oscillation section 70 and applied to a sampling frequency signal for sampling of the image signal. do.

On the other hand, an image signal (see FIG. 5 (a)) of the projection target is applied to the analog-digital conversion unit 80 to perform sampling based on the sampling frequency signal. The sampling amount gradually extends from the first horizontal scan line 1H to the Nth horizontal scan line nH in the image correction direction by the sampling frequency signal oscillated in the form shown in FIG. It is stored in the first frame memory 90 to be performed (see FIG. 5 (b)).

In such a state, the counter 110 counts the sampling frequency signal CK applied to the sampling of the image signal in the analog-digital conversion unit 80 to detect the amount of sampled data in each horizontal scan line. And a counter 110 to the horizontal sync signal Hsync of the image signal separated by the horizontal sync signal separator 100 to detect the amount of data in each horizontal scan line. By resetting, the sampling data amount for the entire horizontal scan line is detected.

The operation control unit 120 generates black data BD for each horizontal scan line based on the count result of the amount of data in each horizontal scan line provided from the counter 110 to control signal CT. The control signal RD is applied to the first frame memory 90 while being applied to the buffer 130 so that the image data stored in the first frame memory 90 is read in the buffer 130. do.

That is, the operation control unit 120 [Hp-Cr / 2 · (integer)] (where Hp is one horizontal scanning line) from the first horizontal scanning line 1H to the Nth horizontal scanning line nH. The number of pixels included in Cr, the amount of data counted by the counter 110, is calculated so that black data is recorded before and after the image data of each horizontal scan line by the number corresponding to the calculation result.

Therefore, in the buffer 130, black data is additionally processed to the image data for each horizontal scan line and stored in the second frame memory 140 (see FIG. 5C), and the stored image data and the black data. The analog signal is converted by the image signal processor 150 and output as a pixel driving signal of an image signal projected on the screen 20.

Therefore, in the upward projection correction mode, when the original image (see FIG. 5 (a)) is projected on the screen, an inverted rhombus screen is formed, but in the present invention, from the upper side to the lower side of the screen relative to the original image. Sampling of the image signal in the form of gradually increasing the amount of sampling data along the direction of the image correction to (see FIG. 5 (b)), and then adding black data to the image signal (see FIG. 5 (c)). When projecting onto the screen, a normal screen is formed on the screen (see FIG. 5 (d)).

On the other hand, when the downward projection correction mode is set by the board mode setting unit 40 and the downward slope correction key 40b is operated, the control unit 50 performs sampling in the form shown in FIG. 4 (b). A control signal for generating a frequency is applied to the integrating circuit section 60, and a voltage signal obtained from the integrating circuit section 60 is applied to the oscillating section 70 to generate a sampling frequency signal.

Therefore, the original image signal to be sampled by the analog-to-digital conversion unit 80 (see FIG. 5 (e)) is different from the upward tilt correction mode described above, and the amount of sampling data in the lower portion of the screen in the image correction direction. Sampling is performed in a smaller form than the amount of sampling data in this upper portion, and the sampled image data is stored in the first frame memory 90 (see FIG. 5 (f)).

In this state, the counter 110 counts the amount of data sampled in each of the horizontal scan lines 1H-nH and provides it to the calculation controller 120 similarly to the upward slope correction mode. ) Generates black data based on the count result to be buffered in the buffer 130 based on the control signal CT and also applies the control signal RD to the first frame memory 90. The stored image data is read into the buffer 130.

Therefore, the image data and the black data that have been processed in the buffer 130 are applied to the second frame memory 140 and stored (see FIG. 5G), and the stored image data and the black data are stored in the image signal processing unit. It is applied to 150 to generate a pixel drive signal.

Therefore, even in the downward slope correction mode, when the original image (see FIG. 5 (e)) is projected on the screen in the upward projection correction mode, a rhombus screen is formed. Sampling the image signal in a form in which the amount of sampling data gradually increases along the image correction direction from the lower side to the upper side of the screen (see FIG. 5 (f)), and then adds black data to the image signal (FIG. 5). (g)), when projected on the screen, a normal screen is formed on the screen (see FIG. 5 (h)).

As described above, according to the asymmetric screen correcting apparatus of the projection type image display system according to the present invention, when the projection type image display system is installed such that the projection angle of the image is maintained at the upward or downward inclination angle with respect to the screen, The screen display efficiency can be remarkably improved by allowing a normal screen to be projected by inversely correcting the asymmetric screen.

Claims (6)

Pixel driving means for displaying a color image signal for an image signal and a pixel driving panel for causing a color image to be projected onto the screen 20 via a projection lens for a pixel driven by the pixel driving means. In the projection type image display system, a correction control for generating a sampling signal of an image signal in an image correction direction opposite to the projection angle by setting a correction mode and a correction amount corresponding to the image projection angle of the projection lens with respect to the screen 20. Image correction means for sampling the projected image signal by means of a sampling signal generated under the control of the correction control means, and black data insertion correction for the image signal in the image correction direction sampled by the image correction means. The black on the periphery of the image signal by the arithmetic control means for performing the Adding process by the asymmetric correction screen of the projection type image display system of the projection angle to help line the corrected image signal from the image correction in the reverse direction characterized in that configured and equipped with image correction processing means for applying to the image device, the data driving unit. 2. The correction mode setting unit (40) according to claim 1, wherein the correction control means includes a correction mode setting unit (40) for setting an image correction mode for the image projection angle and setting a correction amount corresponding to the projection angle under the image correction mode, and the correction thereof. A control unit 50 for generating a control signal corresponding to the correction amount set by the mode setting unit, an integrating circuit unit 60 for integrating the control signal provided from the control unit to generate a voltage signal, and a voltage signal generated by the integrating circuit unit And an oscillation unit 70 for generating a determined sampling frequency, wherein the correction mode setting unit includes an upward slope correcting key 40a for adjusting the amount of correction during upward projection and a downward slope for adjusting the amount of correction during downward projection. Asymmetric screen correction apparatus for a projection image display system, characterized in that a correction key (40b) is provided. The control unit 50 according to claim 2, wherein the control unit 50 generates a control signal for gradually extending the image signal and the sampling area from the first horizontal scan line to the Nth horizontal scan line when the upward tilt correction mode is set. And when the downward slope correction mode is set, generate a control signal to gradually decay the sampling area of the image signal from the first horizontal scan line to the Nth horizontal scan line. Asymmetrical screen compensator The digital image processing apparatus as claimed in claim 1, wherein the image correction means includes: an analog-digital conversion unit (80) for sampling in units of horizontal lines based on the sampling frequency in an image correction direction opposite to the projection angle with respect to the projected image signal; A first frame memory (90) storing the sampled image signal, a horizontal synchronous signal separator (100) for separating the horizontal synchronous signal of the image signal, and reset the horizontal synchronous signal to count the sampling frequency And determining a quantity of black data to be added to the periphery of the sampled line-level image signal, wherein the counter comprises a counter (110). The image correction processing unit of claim 1, wherein the black data is corrected by adding the black data to the buffer 130 in which the sampled image data and the black data are buffered, and the sampled image data applied through the buffer. The second frame memory 140 in which the image data is stored, and the image signal processor 150 for generating a pixel driving signal for projecting the image data and the black data stored in the second frame memory onto the screen 20. Non-symmetrical screen correction apparatus of the projection type image display system, characterized in that comprising a. According to claim 1, The black data generated by the operation control means 120 is the amount of data that is stored from the first horizontal scan line to the N-th horizontal scanning line gradually expanded when the upward tilt correction mode is set On the other hand, the asymmetric screen of the projection type image display system is generated such that the amount of data added from the first horizontal scanning line gradually reduced in setting the downward tilt correction mode is increased from the horizontal scanning line to the Nth horizontal scanning line. Compensator.