CN100444627C - Image display device and correction value preparation method thereof - Google Patents

Abstract

To provide a method of generating correction data for an image display device capable of correcting an image with high precision without requiring a large amount of correction value. The correction data generating method of the image display device includes: a distribution detection step (S21) for detecting the distribution of output characteristic values of the image displayed on the screen; The equipotential line interval setting step (S22) of the interval of the equipotential line of the pixel; According to the equipotential line interval of setting, set the equipotential line setting step (S23) of a plurality of equipotential lines; The node setting step (S25) of setting a plurality of nodes on each equipotential line; the segmentation element setting step (S26) of dividing the image displayed on the above-mentioned screen into a plurality of element regions according to the set nodes; Correction value setting steps (S27), (S28) of setting a correction value for each divided element area.

Description

Image display device and correction value preparation method thereof

technical field

The present invention relates to an image display device, a correction value creation method for the image display device, a correction value creation program for the image display device, and a recording medium recording the program.

Background technique

In a fixed-pixel image display device such as a projector, a liquid crystal display, or a plasma display, when an image is displayed by an image generating device that is paired with a screen for displaying an image, the luminance output of a part of the image displayed on the screen may be Distribution occurs in output characteristic values such as value and color output value, and such a deviation is seen as unevenness in brightness and unevenness in color of an image displayed on the screen. It is generally considered that such brightness unevenness, color unevenness, and the like are caused by manufacturing errors or the like of elements constituting pixels of an image generating device such as a liquid crystal light valve.

Such brightness unevenness, color unevenness, and the like can be eliminated by correcting an electrical signal that produces a distribution of output characteristic values on a pixel-by-pixel basis, and various correction methods have been proposed conventionally.

For example, a technique has been proposed in which, when determining the amount of correction of color unevenness of an image displayed on the screen, correction data for each gradation is stored in advance for the entire image displayed on the screen, and the screen is divided into checkerboards. In a grid pattern, color unevenness is corrected according to gradation by applying correction data to each divided image (for example, refer to Patent Document 1).

In addition, as another example, a technique has been proposed that divides an image displayed on the screen into triangle elements, generates correction data at each vertex of the triangle element, and interpolates the triangle element inside from the correction data at each vertex. The correction data of the image is used to correct the color unevenness of the image (for example, refer to Patent Document 2).

[Patent Document 1] JP-A-2000-284773 (Fig. 1, paragraphs [0024] to [0029])

[Patent Document 2] Japanese Unexamined Patent Publication No. 2000-316170 (Fig. 2, paragraph [0068])

However, the technology disclosed in the above-mentioned patent document divides and displays an image using uniform polygonal elements and performs correction within each divided element, and has the following problems.

That is, if the precision of correction is to be improved and a high-quality image is obtained, the number of divisions of the screen must be increased, and the amount of correction values stored in a lookup table of the image display device becomes huge, and there is a need for storing such a lookup table. The problem of large-capacity memory.

On the other hand, in order to reduce the amount of correction values as much as possible, it is conceivable to divide with large polygonal elements and store correction values corresponding to a small number of divided elements in a lookup table. However, in this case, since the correction based on the correction value tends to be rough and the image cannot be corrected with high accuracy, there is a problem that a large improvement in image quality cannot be expected. In particular, there is a high possibility that the image cannot be successfully corrected for an image with local uneven brightness, uneven color, or the like.

Contents of the invention

An object of the present invention is to provide a correction value generation method for an image display device capable of correcting an image with high precision without requiring a large amount of correction value, a program for causing a computer to execute the method, and an image display device.

The correction value preparation method for an image display device according to the present invention is to prepare the correction value for an image display device having an image display having a distribution in output characteristic values of an image generation device paired with a screen displaying an image. The unit and the correction unit that corrects the input image signal according to the correction value corresponding to the distribution of the above-mentioned output characteristic value and outputs it to the above-mentioned image display device are characterized in that they include:

a step of detecting the distribution of the output characteristic value of the image displayed on the above-mentioned screen;

A step of setting nodes within the output characteristic distribution according to the detected output characteristic distribution;

The step of connecting the set nodes to each other and dividing into multiple element areas;

Steps to set the correction value for each segmented feature area.

According to the present invention, since the nodes are set according to the distribution of the detected output characteristic values of the image, the set nodes are connected to each other and divided into a plurality of element regions, and correction values are set for each element region, it is possible to set By determining an appropriate correction value according to the distribution of the output characteristic value, the amount of the correction value will not be large, and correction can be performed with high accuracy.

Here, the correction value creation method of the image display device of the present invention can be achieved by the following two methods, not only the invention related to the correction value creation method, but also as an image having correction values created by each correction value creation method A display device, a program for causing a computer to execute the correction value creation method, and a recording medium on which the program is recorded are also provided.

■1. Method of making correction value using equipotential line of distribution of output characteristic value

The image display device of the present invention is provided with: an image display unit having a distribution in output characteristic values of an image generating device paired with a screen displaying an image, and correcting an input image based on a correction value corresponding to the distribution of the above-mentioned output characteristic values. After the signal is output to the correction unit of the above-mentioned image display unit, it is characterized in that,

The correction unit above has:

According to the distribution of output characteristic values, a plurality of equipotential lines connecting pixels in the image displayed on the above-mentioned screen with approximately equal output characteristic values are set, and the display on the above-mentioned The image on the screen is divided into a plurality of element areas, and the correction value storage unit stores the correction value for each divided element area;

A correction processing unit that corrects the input image signal for each of the element regions based on the correction value stored in the correction value storage unit.

According to the present invention, the image displayed on the screen is divided into a plurality of element regions according to the plurality of nodes set on the equipotential line, and by setting the correction value according to each divided element region, it can be compared with the image displayed on the screen. The distribution of the output characteristic value of the image is corrected accordingly, and the distribution of the output characteristic value can be corrected with high precision. Therefore, high-precision correction can be performed with fewer correction values than conventional methods, and it is possible to install an image display device that displays high-quality images without providing a large-capacity memory for storing correction values.

In the present invention, the element areas are preferably non-overlapping polygonal element areas formed by connecting nodes on the equipotential lines with straight lines, and the correction value storage unit is provided with node position information that stores the position of each element area on the screen. , and an element area storage table for correction parameters of element areas given by node position information, and a correction value table for storing correction values corresponding to the correction parameters.

According to the present invention, since the information on the elements and the correction value to be actually corrected are stored in separate tables, the amount of data on the correction value can be reduced.

In the present invention, it is preferable to store a plurality of correction values corresponding to different grayscale images in the correction value storage unit.

According to the present invention, by storing a plurality of correction values corresponding to the gamma characteristics of the image display unit, etc., appropriate correction can be performed according to the gradation of the image displayed on the image display unit, so it is possible to set up a system capable of displaying higher quality images. image display device.

In the present invention, it is preferable that the output characteristic value is a luminance output value or a color output value of the image generating device described above.

According to the present invention, since unevenness in brightness and unevenness in color that are likely to cause problems as an image display device can be corrected, it is possible to provide an image display that can provide high-quality images by appropriately correcting deviations in these image display units that are easily noticed. device.

The correction value creation method of the image display device according to the present invention is to store the correction value in the correction means of the above-mentioned image display device. Specifically, the method for creating a correction for an image display device according to the present invention creates the above-mentioned correction value for an image display device that has a distribution in output characteristic values of an image generating device that is paired with a screen that displays an image. An image display unit; according to the correction value corresponding to the distribution of the above-mentioned output characteristic value, the input image signal is corrected and then output to the correction unit of the above-mentioned image display unit, which is characterized in that it includes:

a distribution detecting step of detecting a distribution of output characteristic values of the image displayed on the above-mentioned screen;

An equipotential line interval setting step of setting intervals of equipotential lines connecting pixels with approximately equal output characteristic values according to the detected distribution of output characteristic values;

According to the set equipotential line interval, set the equipotential line setting steps of multiple equipotential lines;

A node setting step for setting a plurality of nodes on each set equipotential line;

A division element setting step of dividing and setting the image displayed on the above-mentioned screen into a plurality of element regions according to the set nodes;

Steps to set the correction value for each segmented feature area.

According to the present invention, since the correction value stored in the correction means of the image display device can be created with the minimum necessary amount of data, it is not necessary to use a storage means such as a large-capacity memory in the image display device. In addition, since the correction is performed based on a plurality of nodes set on the equipotential line, the output characteristic value of the image displayed on the screen can be corrected according to the distribution, and a correction value that can be corrected with high accuracy can be obtained.

In the present invention, the following method can be considered as the above-mentioned equipotential line interval setting step.

(1) According to the distribution of the detected output characteristic value, the step of detecting the part of the output characteristic value that is farthest from the output characteristic value that should be displayed, and setting the equipotential line interval near the obtained detection part It is a method to set the equipotential line interval in steps that are narrower than other parts. According to such a method of setting equipotential line intervals, since it is possible to very carefully correct parts that are particularly conspicuous, such as brightness unevenness and color unevenness, in a small element area, when correcting the distribution of output characteristic values with peaks, efficient.

(2) Through the step of generating a histogram corresponding to the output characteristic value from the distribution of the detected output characteristic value, and setting the interval of the equipotential line near the peak value of the generated histogram to be narrow, the equipotential is set method of line spacing. According to such an equipotential line interval setting method, since it is possible to carefully correct brightness unevenness, color unevenness, etc. in a small element area in a wide range, it is effective in correcting vibrating brightness unevenness, color unevenness, etc. Valid in the distribution of the output characteristic values of .

In the present invention, it is preferable that the output characteristic value is a luminance output value or a color output value of the image generating device described above.

According to the present invention, since unevenness in brightness and unevenness in color that tend to be a problem in an image display device can be corrected, it is possible to create a correction value that can appropriately correct variations in these easily visible image display units.

The correction value creation program for an image display device of the present invention is characterized in that it causes a computer to execute the correction value creation method for an image display device described above, and the recording medium of the present invention records the correction value creation program.

According to these inventions, it is possible to create an appropriate correction value only by implementing the correction value creation method described above by installing it in a general-purpose computer.

2. A method of making a correction value using the extreme value of the distribution of the output characteristic value

The image display device of the present invention is provided with: an image display unit having a distribution on the output characteristic value of the image generating device paired with the screen displaying the image; The correction unit that outputs to the above-mentioned image display unit is characterized in that,

The correction unit above has:

The distribution of the output characteristic value in the image displayed on the screen is set as the maximum or minimum extreme value of the output characteristic value as a node, and the image displayed on the above-mentioned screen is divided into a plurality of element areas, and a correction value storage unit storing a correction value for each divided element area;

A correction processing unit that corrects the input image signal for each of the element regions based on the correction value stored in the correction value storage unit.

According to the present invention, by setting the extremum of the distribution of output characteristic values as a node and dividing it into a plurality of element regions, correction can be performed according to the distribution of output characteristics of the image displayed on the screen, and correction can be performed with high accuracy. Outputs the distribution of feature values. Therefore, high-precision correction can be performed with fewer correction values than conventional methods, and it is possible to provide an image display device capable of displaying high-quality images without providing a large-capacity memory for storing correction values.

In the present invention, it is preferable that the correction value storage unit has an element area storage table storing node position information indicating the position in the screen of each element area, and an element area storage table which stores correction parameters of the element area specified by the node position information, and stores an element corresponding to the correction parameter. The correction value storage table of the correction value.

According to the present invention, since the information on the elements and the correction value to be actually corrected are stored in separate tables, the amount of data on the correction value can be reduced.

In the present invention, it is preferable to store a plurality of correction values corresponding to different grayscale images in the correction value storage unit.

According to the present invention, by storing a plurality of correction values corresponding to the gamma characteristics of the image display unit, appropriate correction can be performed corresponding to the gradation of the image displayed by the image display unit, so it can be set to display higher quality images. An image display device for an image.

In the present invention, it is preferable that the output characteristic value is a luminance output value or a color output value of the image generating device described above.

According to the present invention, since unevenness in brightness and unevenness in color, which tend to be a problem in an image display device, can be corrected, it is possible to provide an image display device capable of providing high-quality images by appropriately correcting variations in these image display units that are easy to see. .

The method for creating a correction value of an image display device according to the present invention creates a correction value stored in a correction unit of the above-mentioned image display device. Specifically, the correction value preparation method of an image display device according to the present invention produces the above-mentioned correction value of an image display device having: The distributed image display unit, and the correction unit that corrects the input image signal according to the correction value corresponding to the distribution of the above-mentioned output characteristic value and outputs it to the above-mentioned image display unit, is characterized in that it includes:

a distribution detecting step of detecting a distribution of output characteristics of the image displayed on the above-mentioned screen;

An extremum setting step of setting a maximum or minimum extremum of the distribution of output characteristic values according to the detected distribution of output characteristics;

A division element setting step of dividing the image displayed on the above-mentioned screen into a plurality of element regions by using the set extremum as a node;

A correction value setting procedure for setting a correction value for each divided element area.

Here, the correction value made according to the present invention can be suitably used for image correction of a fixed-pixel image display device, for example, in addition to an organic EL display, a liquid crystal display, and a plasma display, it can be applied to modulation of a secondary light source according to image information. A projector that magnifies and projects an optical image using the emitted light beams.

In addition, in the extreme value setting step, for example, when an image signal for displaying all pixels with the same luminance value is input, the pixel position with the highest luminance compared with the surrounding area and the pixel position with the lowest luminance compared with the surrounding area are used as the extreme value. value to set.

Furthermore, as a method of element division by the division element setting step, for example, Delaunay's triangulation method used in spatial data modeling can be used.

According to the present invention, since the correction value stored in the correction means of the image display device can be created with the minimum amount of data required, it is not necessary to use storage means such as a large-capacity memory in the image display device. In addition, since the correction is performed based on the node set as the extremum of the output characteristic value, the image displayed on the screen can be corrected according to the distribution of the output characteristic value, thereby performing high-precision correction.

In the present invention, after the step of setting the correction value, it is preferable to include a corrected distribution obtaining step of obtaining the distribution of the output characteristics of the image corrected by the prepared correction value, and a step of correcting the image based on the distribution of the corrected output characteristic. For the judgment of good or bad, if it is judged to be bad, the correction image evaluation steps from the extreme value setting step to the correction value setting step are carried out again.

According to the present invention, although the amount of data increases compared with the creation of the correction value only once, since the image quality can be greatly improved by setting a finer correction value, it is possible to obtain a corresponding increase in the amount of data. It is possible to display correction values of images of much higher quality than conventional correction methods.

In the present invention, it is preferable that in the second extreme value setting step, a new extreme value is added to the extreme value set in the previous extreme value setting step.

According to the present invention, since the division elements are set by adding new extremums as nodes in addition to the extremums set when the first correction value was generated, the precision of the newly generated correction data is comparable to that of the previous correction data. Ratio is indeed improved.

In the present invention, it is preferable that the output characteristic value is a luminance output value or a color output value of the image generating device described above.

According to the present invention, since unevenness in brightness and unevenness in color that tend to be a problem in an image display device can be corrected, it is possible to create a correction value that can appropriately correct variations in these image display devices that are easy to see.

The correction value creation program for an image display device of the present invention is characterized in that it causes a computer to execute the correction value creation method for an image display device described above, and the recording medium of the present invention is characterized in that the correction value creation program is recorded therein.

According to these inventions, an appropriate correction value can be created by installing it in a general-purpose computer and implementing the above-mentioned correction value creation method.

Description of drawings

FIG. 1 is a schematic diagram showing the configuration of a correction data creating device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram illustrating detection of unevenness in brightness by the unevenness in brightness detection unit of the above embodiment.

FIG. 3 is a flowchart showing the operation of the brightness unevenness detection unit of the above-mentioned embodiment.

FIG. 4 is a schematic diagram for explaining setting of equipotential line intervals in the above embodiment.

FIG. 5 is a flowchart showing a method of setting equipotential line intervals in the above embodiment.

FIG. 6 is a schematic diagram for explaining the setting of equipotential line intervals in the above-mentioned embodiment.

FIG. 7 is a schematic diagram for explaining setting of equipotential line intervals in the above-mentioned embodiment.

FIG. 8 is a schematic diagram showing a data structure of an equipotential line interval storage unit for storing set equipotential line intervals according to the above-mentioned embodiment.

FIG. 9 is a flowchart showing the procedure of equipotential line setting in the above embodiment.

FIG. 10 is a schematic diagram showing a data structure of an equipotential line storage unit storing set equipotential lines in the above-mentioned embodiment.

FIG. 11 is a flowchart illustrating a method of setting a representative value for the equipotential line set according to the above-mentioned embodiment.

FIG. 12 is a schematic diagram for explaining a method of setting a representative value in the above-mentioned embodiment.

FIG. 13 is a flowchart showing the procedure of polygon element region division and correction value setting by the polygon division means in the above-mentioned embodiment.

FIG. 14 is a schematic diagram for explaining a method of dividing a polygon element region and setting a correction value by a polygon dividing unit according to the above-mentioned embodiment.

FIG. 15 is a flowchart showing the procedure of polygon element region division by the polygon division unit in the above-mentioned embodiment.

FIG. 16 is a schematic diagram for explaining a method of dividing a polygon element region by a polygon dividing unit according to the above-mentioned embodiment.

FIG. 17 is a schematic diagram for explaining correction values created in the above-mentioned embodiment.

FIG. 18 is a schematic diagram showing a data structure of correction values created in the above embodiment.

FIG. 19 is a schematic diagram showing a data structure of correction values created in the above embodiment.

FIG. 20 is a flowchart illustrating the operation of the correction data creating device of the above-mentioned embodiment.

21 is a schematic diagram of an image processing circuit of a projector including a correction data storage unit that stores correction values created by the correction data creation device of the above-mentioned embodiment.

FIG. 22 is a schematic diagram showing the configuration of a correction number creation device according to an embodiment of the present invention.

FIG. 23 is a schematic diagram showing detection of unevenness in brightness by means for detecting unevenness in brightness in the above embodiment.

FIG. 24 is a flowchart showing the operation of the brightness unevenness detection unit of the above-mentioned embodiment.

FIG. 25 is a schematic diagram showing brightness unevenness extreme value setting by the brightness unevenness extreme value setting unit according to the above embodiment.

FIG. 26 is a flowchart showing the operation of the luminance unevenness extreme value setting unit in the above-mentioned embodiment.

FIG. 27 is a schematic diagram for explaining a method of setting extreme values of brightness unevenness in the above-mentioned embodiment.

Fig. 28 is a flowchart showing the procedure for setting extreme values of brightness unevenness.

FIG. 29 is a flowchart showing the procedure of polygon element region division by the polygon division unit in the above-mentioned embodiment.

FIG. 30 is a schematic diagram for explaining a method of dividing a polygon element region by a polygon dividing unit according to the above-mentioned embodiment.

FIG. 31 is a schematic diagram for explaining correction values created in the above embodiment.

Fig. 32 is a schematic diagram showing a data structure of correction values created in the above embodiment.

FIG. 33 is a schematic diagram showing a data structure of correction values created in the above embodiment.

FIG. 34 is a flowchart showing the flow of good or bad judgment and evaluation of a corrected image by the correction data judging means according to the above-mentioned embodiment.

FIG. 35 is a schematic diagram for explaining extremum setting and polygonal element region division performed again after the quality judgment by the correction data judging means according to the above-mentioned embodiment.

36 is a graph for explaining extremum setting and polygonal element region division performed again after the quality judgment by the correction data judging means according to the above-mentioned embodiment.

FIG. 37 is a schematic diagram for explaining extremum setting and polygonal element region division performed again after the quality judgment by the correction data judging means according to the above-mentioned embodiment.

FIG. 38 is a graph for explaining extremum setting and polygonal element region division performed again after the quality judgment by the correction data judging means according to the above-mentioned embodiment.

Fig. 39 is a flowchart illustrating the operation of the correction data creating device of the above-mentioned embodiment.

40 is a schematic diagram of an image processing circuit of a projector including a correction data storage unit storing correction values created by the correction data creation device according to the above embodiment.

Symbol Description

1...Correction data creation device, 100...Projector, 101...Correction data storage unit, 103...Conversion processing unit, 411...Brightness unevenness detection unit, 412...Etc. Line setting means, 413... Representative value setting means, 414... Correction data generating means, 415... Polygon division means, 416... Node value setting means, 417... Element value setting means Unit setting, S3, S21... distribution detection steps, S7, S22... equipotential line interval setting steps, S8, S23... equipotential line setting steps, S14, S26... division element setting Setting step, S15, S20, S27, S28...Correction value setting step, S18, S25...Node setting step, B1...Correction data preparation device, B411...Brightness unevenness detection unit, B412...Brightness unevenness extreme value setting unit, B413...Polygon division unit, B414...Node value setting unit, B415...Element value setting unit, B416...Correction data judging unit , BS3, BS15...Distribution detection unit, BS6, BS16...Extreme value setting procedure, BS8, BS17...Segment element setting procedure, BS12, BS20...Corrected distribution acquisition procedure, BS13, BS14 , BS21... Corrected image evaluation procedure, BS9, BS18, BS19... Corrected value setting procedure

Detailed ways

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

[Embodiment 1]

1. Configuration of correction data creating device 1

(1) Overall configuration of the device

1 shows a schematic diagram of a correction data creation device 1 for a projector according to Embodiment 1 of the present invention. This correction data creation device 1 is equipped with a screen 2, a CCD camera 3, and a computer 4, and is used to create corrections as correction data. A device that creates correction data for brightness unevenness in distribution of output characteristic values of a projection image of a target projector 100 .

The screen 2 is a portion for projecting a projected image of the projector 100 to be the object of correction data, and the CCD camera 3 has a function as an imaging device for capturing a projected image projected on the screen 2, and the image captured by the CCD camera 3 is converted into The electrical signal is output to the computer 4 .

The computer 4 reads the image captured by the CCD camera 3 and performs image processing to generate correction data for the projector 100 .

The correction data generated by the computer 4 is stored in a correction data storage unit 101 provided in a memory or the like in the projector 100, and when an image is projected by the projector 100, the correction data stored in the correction data storage unit 101 is used to After correcting the image signal, the image is projected, and the details will be described later.

The computer 4 includes a CPU 41 and a storage device 42 , and the electrical signals related to the images captured by the CCD camera 3 are converted into digital image data and processed by the CPU 41 .

The CPU 41 includes a brightness unevenness detection unit 411, an equipotential line setting unit 412, a representative value setting unit 413, and a correction data generation unit 414 as a program developed on the calculation area, and stores these detected values in the storage device 42. , setting values, etc., a luminance uneven distribution storage unit 421 , an equipotential line storage unit 422 , an equipotential line interval storage unit 423 , and a representative value storage unit 424 are secured in a part of the storage area.

(2) The composition of the functional units in the CPU41

(2-1) Configuration of brightness unevenness detection unit 411

The brightness unevenness detection unit 411 detects brightness unevenness based on the output from the CCD camera 3 that captures the projection image projected from the projector 100 , and specifically executes the processing in FIGS. 2 and 3 .

First, the brightness unevenness detection unit 411 inputs the projection image data TP for brightness unevenness detection to the projector 100 to be corrected data, and projects a projection image corresponding to the image data from the projector 100 on the screen 2. on the projection plane (processing S1). In addition, the projected image data TP for detecting brightness unevenness at this time is displayed as a monochromatic image of a constant gradation.

Next, brightness unevenness detection section 411 captures a projection image projected on the projection surface with CCD camera 3 as an imaging device, and takes in projection data A1 as digital data (process S2 ).

Finally, image processing is performed so that the brightness unevenness is accurately reflected in the projection data A1, the brightness uneven distribution A2 serving as the distribution of the output characteristic value is obtained, and the data is stored in the brightness uneven distribution storage unit 421 (processing S3: distribution detection step) .

(2-2) Configuration of equipotential line setting unit 412

The equipotential line setting unit 412 sets the interval of equipotential lines with equal luminance unevenness based on the obtained uneven luminance distribution A2, and sets, etc. The part of the bit line, specifically, executes the processing shown in FIG. 4 and FIG. 5 .

First, the equipotential line setting section 412 acquires the uneven brightness distribution A2 stored in the uneven brightness distribution storage unit 421 (processing S4).

Next, equipotential line setting section 412 acquires the maximum value and the minimum value of brightness unevenness from acquired brightness unevenness distribution A2 (processing S5).

Furthermore, equipotential line setting section 412 obtains histogram A3 of uneven brightness from distribution of uneven brightness A2 (processing S6 ).

The equipotential line setting section 412 sets the equipotential line intervals based on the obtained histogram A3 (processing S7: equipotential line interval setting step).

For example, when the brightness uneven distribution image A4 shown in FIG. 6 is obtained, and the brightness uneven distribution is in the state shown in the histogram A5, when E≥160, 140≤E<160, 120≤E< 140, E<120, when equipotential line intervals are taken at equal intervals, the non-uniform brightness distribution image A4 is classified like the image A6. On the other hand, when the intervals of equipotential lines are taken at different intervals in the manner of E≥160, 150≤E<160, 130≤E<150, E<130, the brightness uneven distribution image A4 is like image A7 Sort it that way. That is, the setting of the equipotential line interval by the equipotential line setting section 412 can be arbitrarily set depending on what kind of correction is to be performed.

In more detail, for example, as shown in FIG. 7 , when obtaining a brightness uneven distribution image A9 having a brightness uneven distribution like the histogram A8, the equipotential line setting unit 412 may Equipotential lines A at equal intervals as in image A10 , equipotential lines B at unequal intervals as in image A11 , and equipotential lines C at unequal intervals as in image A12 are freely set.

Equipotential line A is the simplest equipotential line interval setting method for equal interval setting, and has the advantage of not requiring special processing during interval setting.

The equipotential line B is a method of setting an equipotential line interval narrowing the interval around the maximum value of the luminance uneven distribution, and the equipotential line interval is narrowed in the approximate center of the luminance uneven distribution image A9. According to such a setting method, correction data capable of finely correcting particularly conspicuous unevenness can be set, which is effective in correcting unevenness having peaks.

The equipotential line C is a method of setting the equipotential line interval that narrows the interval near the peak value of the histogram A8 of the brightness uneven distribution image A9, and the equipotential line interval narrows in the peripheral portion of the brightness uneven distribution image A9. . According to such a setting method, correction data capable of finely correcting brightness unevenness spreading over a wide area can be set, which is effective in correcting chattering unevenness.

The respective equipotential line intervals set in this way are stored in the equipotential line interval storage unit 423 as a table T1 in which the equipotential line interval number, the minimum value of brightness unevenness, and the maximum value of brightness unevenness are recorded as one record, as shown in FIG. middle.

Returning to FIG. 5 , if the setting of the equipotential line interval ends, the equipotential line setting unit 412 sets the equipotential line according to the brightness uneven distribution A2 and the set equipotential line interval (processing S8: equipotential line line setting procedure).

The setting of the equipotential lines is specifically performed according to the procedure shown in the flowchart of FIG. 9 .

First, the equipotential line setting section 412 reads the luminance non-uniform distribution A2 (process S81), and then reads the equipotential line interval T1 (process S82).

Next, equipotential line setting section 412 calculates the uneven distribution of brightness in which the uneven distribution of brightness is replaced by the equipotential line interval number (processing S83). That is, the uneven brightness distribution image A4 shown in FIG. 6 is replaced with images such as the image A6 and the image A7.

Finally, the equipotential line setting unit 412 calculates the equipotential line using the boundary line tracing method (processing S84). As the boundary line tracing method, one of the 4-connection boundary line tracing method and the 8-connection boundary line tracing method can be used.

As shown in FIG. 10, all the calculated equipotential lines are stored in the equipotential line storage unit 422 as a table T2 in which the equipotential line numbers, luminance unevenness values, boundary point numbers, and boundary point position information are recorded as one record. .

(2-3) Configuration of representative value setting unit 413

The representative value setting unit 413 is a part that sets the representative value of the luminance correction parameter for correcting luminance unevenness based on the equipotential line data set in the equipotential line setting unit 412. Figure 12 processing.

First, the representative value setting unit 413 reads the data of the equipotential line from the equipotential line storage unit 422 (processing S9). point location information, etc.

Next, the representative value setting section 413 reads a previously prepared brightness unevenness-luminance uneven correction parameter relationship table in which the brightness unevenness and the brightness unevenness correction parameters are associated (process S10). The luminance unevenness-luminance unevenness correction parameter relationship table is a table associating the luminance unevenness E with the correction parameter V as shown in the graph A13 of FIG. The larger the relationship.

Finally, the representative value setting unit 413 sets the luminance correction parameters of each equipotential line corresponding to the value of luminance nonuniformity of each equipotential line or Parameters for calculating brightness correction parameters are set as representative values (processing S11). The representative value includes, for example, a luminance correction parameter number, a corresponding contour line number, and a luminance correction parameter value, and the set representative value is stored in the representative value storage unit 424 .

(2-4) Configuration of correction data generation unit 414

The correction data generation unit 414 is a part that generates correction data to be a correction value based on the equipotential lines set by the equipotential line setting unit 412, and as shown in FIG. The unit 416 and the element value setting unit 417 specifically execute the processing shown in FIGS. 13 and 14 .

First, polygon dividing section 415 acquires equipotential lines in area A14 from equipotential line storage unit 422 as shown in FIG. 14 (process S12 ).

When the acquisition of equipotential lines is completed, polygon dividing section 415 sets a closed region based on equipotential lines shown in region A15 (process S13 ).

When the setting of these closed areas is completed, each closed area is divided into a plurality of polygonal element areas (processing S14: dividing element setting step).

Finally, the node value setting unit 416 and the element value setting unit 417 set the element value used as the brightness correction parameter or the node value used as the parameter for calculating the brightness correction parameter according to each polygonal element area (processing S15: correction value setting steps).

When these settings by polygon dividing section 415 , node value setting section 416 , and element value setting section 417 are described in more detail, they are set in the order shown in FIGS. 15 and 16 .

First, as shown in FIG. 16 , polygon dividing section 415 sets the number of divisions of the closed region boundary based on the closed region boundary L1 based on the equipotential line (processing S16 : node setting step). Furthermore, in FIG. 16, for example, if the number N of divisions of the closed area boundary is set to 6, six nodes P1 to P6 can be set on the boundary line.

Next, the polygon dividing section 415 calculates the length of the boundary dividing line elements from the number of boundary points constituting the closed area boundary L1 and the number of divisions of the closed area boundary (processing S17).

Next, nodes are placed on the closed area boundary based on the closed area boundary L1 and the length of the boundary dividing line element (process S18).

Then, the polygon dividing section 415 performs a process of associating the nodes P1 to P6 on the boundary of the closed area with the triangle element nodes A to F by the Delaunay triangle division method (process S19).

Finally, the node value setting unit 416 sets parameters for calculating brightness correction parameters as node values of each triangle element region from the equipotential line and the node positions of the triangle element region, and the element value setting unit 417 sets the brightness correction parameter As element values corresponding to equipotential lines and triangular element areas (processing S20: correction value setting step).

The final correction data generating section 414 stores the triangle element areas, node values, and element values set by these means as table-structured data set for each triangle element area.

Specifically, for example, as shown in FIG. 17, triangle element nodes A to F are set on the closed area boundary L1 and closed area boundary L2, and triangle element areas 1 to 1 are set between the closed area boundary L1 and the closed area boundary L2. 4. If V1 is set as the element value, the correction data generation unit 414 generates a table T3 as shown in FIG. 18 and a table T4 as shown in FIG. 19 .

Table T3 has node position information (x _A , y _A ), (x _B , y _B ), (x _F , y _F ) ..., A structure in which element value V1 and element node values L1 and L2 are stored in one record. For example, in triangular element area 1 assigned element number 1, node position information is (x _A , y _A ), (x _B , y _B ), (x _F , y _F ), element value V1, The element node value of nodes A and B on the area boundary L1 is L1, and the element node value of node F on the closed area boundary L2 is L2.

Here, in the table T3, the element value V1 and the element node values L1 and L2 are all set as correction parameters, and specific correction data are stored in the correction value table T4 shown in FIG. 19 .

The correction value table T4 stores specific correction data corresponding to the above-mentioned element value V1, element node values L1, L2, etc., and performs correction based on the correction data for each triangle element area based on the two tables T3, T4.

In addition, the element value V1 is the correction parameter in the correction triangle element area, and the element node values L1 and L2 are set as the correction parameters for the nodes. In the case of not using the element value V1 for correction, the element node is calculated by interpolation The values L1 and L2 can be used as correction data.

2. Correction of the function of the data creation device 1

Next, the operation of the correction data creating device 1 including the above-mentioned functional units will be described based on the flow chart shown in FIG. 20 .

The brightness unevenness detection unit 411 inputs the projection image data TP for brightness unevenness detection to the projector 100 to be corrected, and obtains the brightness unevenness distribution from the projection data after being photographed by the CCD camera 3 (processing S21: distribution detection step).

Equipotential line setting section 412 obtains the maximum value and minimum value of brightness unevenness from the acquired brightness uneven distribution, obtains a histogram, and sets the interval of equipotential lines based on the histogram (processing S22: equipotential line interval setting set steps).

Next, equipotential line setting section 412 sets equipotential lines on the uneven distribution of luminance based on the set equipotential line intervals (processing S23: equipotential line setting step).

After the equipotential line is set, the representative value setting unit 413, according to the data of the equipotential line set by the equipotential line setting unit 412 and the brightness unevenness-brightness unevenness correction parameter relation A brightness correction parameter corresponding to the value of the brightness unevenness of the line is set as a representative value (processing S24).

After the setting of the representative value by the representative value setting unit 413 is completed, the polygon dividing unit 415 of the correction data generating unit 414 sets a plurality of nodes on the equipotential line (processing S25: node setting step), The closed area boundaries of the bit lines are divided into a plurality of triangular element areas (processing S26: division element setting step).

Next, for each divided triangle element area, node value setting section 416 sets the element node value on the boundary of the closed area (processing S27: correction value setting step), and element value setting section 417 sets the value of each triangle element Setting of the element value of the area (processing S28: correction value setting step).

The correction data generation unit 414 associates the set element node value and element value with the node position information and the element number of the triangle element area, and writes the correction data of the predetermined grayscale value into the correction data of the projector 100 to be corrected. The storage unit 101 (processing S29).

The correction data generation unit 414 judges whether the correction data of all the grayscale images has been written (processing S30), and if it is determined that the writing is not completed, the grayscale of the projection image data for brightness unevenness detection is changed (processing S31), and from processing S21 The repetition starts, and when the writing of the correction data for all gradations is confirmed, the process ends.

3. Configuration of Projector 100

As shown in FIG. 21, the image processing circuit of the projector 100 that creates the correction data by the above-mentioned correction data creation device 1 is configured to include an A/D converter 102, a conversion processing unit 103, a D/A converter 104, and a liquid crystal. The display drive circuit 105 forms an optical image on the liquid crystal display device after the image signal input from the RGB terminal 106 is processed by the image processing circuit.

The A/D converter 102 is a portion that digitally converts an image signal input as an analog signal, and outputs the digitized image signal to the conversion processing unit 103 .

The conversion processing unit 103 as a correction processing unit includes a correction data storage unit 101 produced by the correction data production device 1 described above. The conversion processing unit 103 corrects the image signal so that the input image signal is converted into a luminance value corresponding to the image signal based on the correction data storage unit 101 .

In the correction data storage unit 101, there are stored a plurality of correction data tables 101A, 101B, 101C, ... which store node position information, node values, and element values corresponding to different gradations. According to the gray level of the image signal, select the appropriate correction data table 101A, 101B, 101C... to correct the image signal. Furthermore, the gradation determination of the input image signal is performed in units of frames, and may be performed by averaging the luminance values of the entire image or based on the luminance value of the image with the largest area.

Then, the image signal corrected by the conversion processing unit 103 is output to the subsequent D/A converter 104 .

The D/A converter 104 is a part that outputs the image signal corrected by the conversion processing unit 13 for analog conversion to the liquid crystal display drive circuit 105 .

The liquid crystal display drive circuit 105 drives the liquid crystal display device based on the corrected image signal input through the D/A converter 104, and projects a projected image on the screen with the uneven brightness eliminated.

According to the projector 100 provided with such a correction data storage unit 101, since the correction data tables 101A, 101B, 101C, ... are stored for each gradation by taking the extremum value of brightness unevenness as a node, the image displayed on the screen The brightness unevenness correction value can be set according to the brightness unevenness, so that the brightness unevenness can be corrected with high precision, and the projector can provide a high-quality image with the minimum amount of data required.

[Embodiment 2]

1. Configuration of correction data creating device B1

(1) The overall structure of the device

22 is a schematic diagram of a correction data creation device B1 for a projector according to Embodiment 2. This correction data creation device B1 is equipped with a screen B2, a CCD camera B3, and a computer B4, and is designed to create correction data for objects to be corrected. A device for correcting correction data for outputting brightness unevenness in characteristic value distribution of a projection image of the projector B100.

The screen B2 is a portion for projecting the projection screen of the projector B100 to be the object of correction data, and the CCD camera B3 has a function as an imaging device for capturing a projected image projected on the screen B2, and the image captured by the CCD camera B3 is converted into a digital image. The signal is output to computer B4.

The computer B4 is a part that takes in an image captured by the CCD camera B3, performs image processing, and generates correction data for the projector B100.

The correction data generated by the computer B4 is stored in the correction data storage unit B101 such as a memory provided in the projector B100, and the correction data stored in the correction data storage unit B101 is used when the projector B100 projects a projected image. The data modifies the image signal and projects an image. Details will be described later.

The computer B4 is equipped with a computing processing device B41 and a storage device B42, and the electrical signal related to the image captured by the CCD camera B3 is converted into digital image data and processed in the computing processing device B41.

The calculation processing device B41 includes a brightness unevenness detection unit B411, a brightness unevenness extremum setting unit B412, a polygon division unit B413, a node value setting unit B414, and an element value setting unit B415 as a program developed on the calculation area. , and the correction data determination unit B416, in order to store these detection values, setting values, etc. in the storage device B42, a luminance uneven distribution storage part B421 and a luminance nonuniform extreme value storage part B422 are secured in a part of the storage area.

(2) The structure of the functional units in the calculation processing unit B41

(2-1) Configuration of brightness unevenness detection unit B411

The brightness unevenness detecting unit B411 is a part that detects brightness unevenness based on the output from the CCD camera B3 that captures the projection image projected by the projector B100, and specifically executes the processing in FIG. 23 and FIG. 24 .

First, the luminance unevenness detection unit B411 inputs the projection image data BTP for luminance unevenness detection to the projector B100 to be corrected data, and the projector B100 projects a projection image corresponding to the image data on the projection screen B2. face (processing BS1). In addition, the projection image data BTP for detecting brightness unevenness at this time is displayed as a monochromatic image of a constant gradation.

Next, brightness unevenness detecting means B411 captures a projected image projected on the projection surface with the CCD camera 3 as the imaging device, and takes in the captured data BA1 as digital data (process BS2).

Finally, image processing is performed so that the brightness unevenness is accurately reflected on the captured data BA1, the brightness uneven distribution BA2 serving as the distribution of the output characteristic value is obtained, and the data is stored in the brightness uneven distribution storage unit B421 (processing BS3: distribution detection step) .

(2-2) Configuration of brightness unevenness extreme value setting unit B412

The brightness unevenness extreme value setting unit B412 is a part that sets the brightness unevenness extreme value based on the obtained brightness unevenness distribution, and specifically, executes the processing in FIG. 25 and FIG. 26 .

First, the luminance uneven extreme value setting unit B412 acquires the luminance uneven distribution BA2 stored in the luminance uneven distribution storage unit B421 (process BS4).

When unevenness in brightness distribution BA2 is obtained, unevenness in brightness extreme value setting unit B412 calculates a part of unevenness in brightness distribution BA2 whose luminance value is higher or lower than those in the vicinity (processing BS5). Specifically, as shown in BA3 of FIG. 25 , when it is determined that the brightness unevenness extremum is as in image BA31 , the extremum number, extremum position, and extremum of each point are calculated as in table BA32 .

Here, determination of extreme brightness unevenness can be realized by executing the processing in FIG. 27 and FIG. 28 .

First, as shown in FIG. 27 , brightness unevenness extreme value setting unit B412 divides and sets a plurality of extreme value search ranges BA51 , BA52 . . . within acquired brightness unevenness distribution BA5 (processing BS51 ).

Next, brightness unevenness extremum setting unit B412 interpolates the distribution of brightness unevenness within the search range using a biquadratic function in each search range BA51, BA52, . . . (processing BS52).

As shown in FIG. 27 , the luminance unevenness extremum setting unit B412 calculates the extremum of the approximation function (the position where the slope of the approximation function = 0) from the biquadratic function BA61 that approximates the luminance unevenness distribution in a certain search range BA5N. ) (processing BS53).

Finally, luminance unevenness extreme value setting unit B412 judges whether there is an extreme value within the search range BA5N, and if so, sets it as an extreme value (processing BS54).

Returning to FIG. 25 and FIG. 26, among the obtained extreme values, the brightness unevenness extreme value setting unit B412 sets the extreme values to be used as nodes, and stores the data of the set extreme value point group in the brightness unevenness point group. In the uniform extremum storage unit B422 (processing BS6: extremum setting step).

The setting of the extremum to be used as a node is performed by deleting as necessary, for example, when there is little variation in the brightness unevenness in the vicinity and the brightness unevenness in the extremum portion as shown in BA4 of FIG. 25 . In addition, in order to perform deletion, it is only necessary to set a threshold value in advance and determine whether or not the threshold value is exceeded. For example, in FIG. 25, if it is determined that there is little variation in brightness unevenness at the extremum portion of point 3 in the image BA41, the calculated extremum number, extremum position, and extremum table BA42 Delete the record of extremum sequence number 3 in , and you can delete the extremum to be used as a node.

(2-3) Configuration of the polygon division unit B413

The polygon division unit B413 divides the image displayed on the screen into polygonal element regions with extreme values as nodes, based on the data of the extreme point group set in the brightness unevenness extreme value setting unit B412, Specifically, the processing shown in FIGS. 29 and 30 is executed.

First, the polygon dividing unit B413 acquires the extremum values of the unevenness in brightness stored in the extremum value storage unit B422 for unevenness in brightness (process BS7).

The polygon dividing unit B413 divides the image displayed on the screen into a plurality of element areas using the point group of the extreme value of brightness unevenness as a node according to the acquired extreme value of brightness unevenness (processing BS8: division element setting procedure).

For the division of the element area, for example, the Delaunay triangulation method in which the polygon element area is made into triangles can be used. That is, as shown in FIG. 30, from the unevenness in brightness distribution BA2 detected by the unevenness in brightness detection means B411, the unevenness in brightness extreme value setting means B412 obtains a point cloud of unevenness in brightness such as image BA41, The polygon division unit B413 performs element division using the extremum as a node, and the image BA41 performs element division using a plurality of triangle elements such as the image BA7.

(2-4) Configuration of node value setting means B414 and element value setting means B415

The node value setting unit B414 and the element value setting unit B415 are parts that generate correction values corresponding to the triangle elements divided by the polygon division unit B413. For example, as shown in FIG. ~4, then the node value setting unit B414 sets the node values of the element nodes A, B, and F of the element 1, for example, when setting the node value of the element 1, and the element value setting unit B415 sets the node value of the element 1 to The element value of the correction value.

Specifically, as shown in FIG. 32 , these units create an element area storage table BT1 that stores the node position of the triangle element, the node value at that time, and the element value based on the triangle element number.

For example, when the XY coordinates of the node position of element number 1 are set on the display image to be corrected, the element node 1 is (x _A , y _A ), the element node 2 is (x _B , y _B ), and the element Node 3 is stored in the form of (x _F , y _F ), and the element value is stored as element V ₁ , and the element node values of element nodes 1 to 3 are stored as L _A , L _B , and L _F in the element number 1. recording.

Here, the element value V ₁ and the element node values L _A , L _B , and _LF are all brightness unevenness correction data (correction values) of the triangle element with element number 1, and in this example, these values are used as correction parameters The setting is performed, and numerical data serving as actual correction values are stored in the correction value table BT2 shown in FIG. 33 . In this correction value table BT2, numerical data serving as actual correction values are stored corresponding to the correction parameters V ₁ , _LA , L _B , and _LF .

Furthermore, the element value _V1 means brightness unevenness correction data (correction value) of the triangular element area assigned element number 1. On the other hand, when the element value V ₁ is not used, the element nodes L _A , L _B , and L _F are used, and the correction values in the triangular element area of the internal element number 1 are calculated by interpolation for the element nodes L A , L B , and L _F . L _B , L _F , the actual brightness unevenness correction data (correction value) in the triangular element area can be calculated.

(2-5) Configuration of Correction Data Determination Unit B416

The correction data determination unit B416 detects unevenness in brightness over the course of projection by the projector B100 based on the brightness unevenness correction data set by the above-mentioned polygon division unit B413, node value setting unit B414, and element value setting unit B415. In the corrected projected image, the brightness unevenness distribution of the corrected image is corrected, and the good or bad of the corrected image is judged, specifically, the processing shown in FIG. 34 is executed.

First, as shown in FIG. 34, the correction data determination unit B416 outputs a control command to the brightness unevenness detection unit B411, and then outputs the projection image data BTP for brightness unevenness detection to the projector B100, and the projector B100 corresponds to the image data. The projected image is projected on the screen after the brightness unevenness is corrected, and the brightness unevenness distribution is obtained by the brightness unevenness detecting unit B411 (processing BS10).

Next, the correction data judging unit B416 acquires the brightness unevenness correction data (correction value) obtained by the above-mentioned units (processing BS11), and calculates the brightness unevenness distribution based on the brightness unevenness distribution newly obtained in the processing BS10 and the brightness unevenness correction data. Brightness uneven distribution after unevenness correction (Process BS12: Corrected distribution acquisition step).

Then, the correction data judging unit B416 sets the extreme value in the brightness unevenness extreme value setting unit B412 for the brightness unevenness distribution after the brightness unevenness correction, and judges whether the set extreme value is good or bad ( Process BS13: Correction image evaluation step). Here, the judgment and evaluation of good or bad can be performed by judging whether the magnitudes of the extremums of the brightness unevenness distribution after the brightness unevenness correction are all within a preset threshold range.

As a result of the good/bad judgment, if it is judged to be within the range of the set threshold, the process ends, and if it is judged to be not within the range of the set threshold, the correction data judging unit B416 sets In the extremum setting when the luminance unevenness correction data is obtained, the threshold value obtained this time is additionally set, and a control command is output to the polygon division unit B413, and element division by the polygon division unit B413 is performed. In the area, let the node value setting unit B414 and the element value setting unit B415 calculate element values and element node values again (processing BS14: corrected image evaluation step).

The evaluation of the corrected image by such a corrected data determination unit B416 will be described in more detail with reference to FIGS. 35 to 38 as follows.

First, as shown in FIG. 35 , the brightness unevenness correction data is generated by the first series of processing, and a distribution such as the brightness unevenness distribution BA8 is acquired by the brightness unevenness detection unit B411. Based on this distribution, brightness unevenness extreme value setting means B412 sets extreme values P11, P12, P13 of brightness unevenness as shown in BA9, and polygon dividing means B413 divides it into a plurality of triangular element regions such as BA10.

If this processing is described using a one-dimensional graph, as shown in FIG. 36, the uneven distribution of brightness can be understood and expressed as a curve like curve BG1, and the extremes of points P11, P12, and P13 that become extreme values are performed from the curve expressed in an understanding. Value setting (curve BG2). Then, the extreme values P11, P12, and P13 are set as triangular divisional element areas L1, L2, and L3 (curve BG3).

Next, as shown in FIG. 37 , unevenness in brightness detection means B411 obtains a distribution such as unevenness in brightness distribution BA11 in the generation of unevenness in brightness correction data based on the second series of processing. Based on this distribution, the extremum values P21 , P22 , P23 . When the polygon division is performed again based on the newly set extremum values P21, P22, P23, .

When this processing is described with a one-dimensional graph as above, the corrected uneven brightness distribution can be understood to be expressed as a graph BG4 as shown in FIG. 38 . Moreover, the parts intersecting the X-axis of the uneven brightness distribution of the curve BG4 are the extremums P11, P12, and P13 set during the previous correction. In these points P11, P12, and P13, because Correction Correction is performed so that brightness unevenness does not occur. The second extreme value setting is performed based on this curve BG4, and new points P21, P22, and P23 are additionally set as extreme values (curve BG5).

Then, if the polygon is divided based on this, as shown in the curve BG6, it is divided into smaller polygonal element regions, and the brightness unevenness is also reduced. Therefore, by repeating this process many times, the uneven brightness distribution can be converged to the direction of infinite disappearance.

2. Correction of the role of the data creation device B1

Next, the overall operation of the correction data creating device B1 equipped with the above-mentioned functional units will be described based on the flow chart shown in FIG. 39 .

The brightness unevenness detection unit B411 inputs the projection image data BTP for brightness unevenness detection to the projector B100 to be corrected, and obtains the brightness unevenness distribution BA2 based on the photographed data BA1 after being photographed by the CCD camera B3 (processing BS15: distribution detection step).

Next, the brightness unevenness extreme value setting unit B412 sets the brightness unevenness extreme value based on the acquired brightness unevenness distribution (processing BS16: extreme value setting step).

When the setting of the extremum of brightness unevenness is completed, the polygon dividing unit B413 divides the image displayed on the screen with extremum point groups as nodes into a plurality of element regions (processing BS17: dividing element setting step).

The node value setting unit B414 sets the node value of each polygonal element area (processing BS18: correction value setting step), and the element value setting unit B415 sets the element value of each polygonal element area (processing BS19 : Correction value setting step) to generate the element area storage table BT1 and the correction value table BT2 shown in FIG. 32 and FIG. 33 .

When the creation of the correction value is completed, the correction data judging unit B416 displays the corrected image corrected based on the element area storage table BT1 and the correction value table BT2 through the brightness unevenness detecting unit B411, and calculates the brightness uneven distribution of the corrected image (processing BS20 ).

The corrected data determination unit B416 makes the brightness unevenness extreme value setting unit B412 set the extreme value according to the brightness unevenness distribution after the brightness unevenness is corrected, and performs the judgment and evaluation of whether the set extreme value is within the threshold range ( process BS21).

When it is determined that it is outside the threshold range, the correction data determination unit B416 adds this extremum value to the extremum value set last time, divides the element area again, and performs each newly divided polygon element The node value setting and element value setting of the area are repeated until the corrected image reaches the threshold value.

On the other hand, when it is determined that it is within the range of the threshold value, correction data determination unit B416 writes the generated element region storage table BT1 and correction value table BT2 into correction data storage unit B101 of projector B100 to be corrected ( process BS22).

When writing to the correction data storage unit B101 is completed, the correction data determination unit B416 determines whether to create a correction value for a different grayscale image (process BS23). In the case of making a correction value for a different grayscale image, change the grayscale of the projection image data for detection (processing BS24), start making the correction value based on the new grayscale image, and repeat the process for the necessary number of grayscale images. The corrected value is made.

■3. Composition of Projector B100

The image processing circuit of the projector B100 that creates the correction data by the above-mentioned correction data creation device B1, as shown in FIG. The liquid crystal display device driving circuit B105 forms an optical image on the liquid crystal display device after the image signal input from the RGB terminal 106 is processed by the image processing circuit.

The A/D converter B102 is a part that digitally converts the image signal input as an analog signal, and outputs the digitized image signal to the conversion processing unit B103.

The conversion processing unit B103 as a correction processing unit includes a correction data storage unit B101 created by the above-mentioned correction data creation device B1. The conversion processing unit B103 converts the input image signal based on the correction data storage unit B101, and corrects the image signal so as to obtain a luminance value corresponding to the image signal.

In the correction data storage unit B101, a plurality of correction data tables B101A, B101B, B101C, ... that store node position information, node values, and element values corresponding to different gradations are stored. The conversion processing unit B103 and the input The gray scale of the image signal correspondingly selects the appropriate correction data table B101A, B101B, B101C... to correct the image signal. In addition, the gradation determination of the input image signal is performed in units of frames, and the luminance values of the entire screen can be averaged, and can be performed based on the luminance value of the image with the largest area.

Then, the image signal corrected by the conversion processing unit B103 is output to the subsequent D/A converter B104.

The D/A converter B104 is a part that converts the image signal corrected by the conversion processing unit B103 into analog and outputs it to the liquid crystal display drive circuit B105.

The liquid crystal display drive circuit B105 drives the liquid crystal display device based on the corrected image signal input via the D/A converter B104, and projects a projected image on the screen with the uneven brightness eliminated.

According to the projector B100 equipped with such a correction data storage unit B101, since the correction data tables B101A, B101B, B101C, . The brightness unevenness correction value is set according to the brightness unevenness of the image, and the brightness unevenness is corrected with high accuracy. Therefore, it is possible to provide a projector that provides a high-quality image with the necessary minimum amount of data.

[Modification of Embodiment]

Furthermore, the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the range in which the object of the present invention can be achieved are naturally included in the present invention.

In Embodiment 1 described above, the present invention is applied to the correction data tables 101A, 101B, 101C, . That is, in the case of color unevenness correction, the present invention can also be applied to create correction data, which can be stored in the correction data storage unit of the projector, and further, the brightness unevenness data and color unevenness correction data can also be stored. Both are pre-stored in the projector, and it is set to be a projector capable of correcting both brightness unevenness and color unevenness at the same time.

In addition, in the first embodiment described above, correction data tables 101A, 101B, 101C, . That is, the present invention can also be applied to self-luminous image display devices such as thin liquid crystal display devices, PDPs, and organic EL displays.

Furthermore, in the above-mentioned second embodiment, the present invention is applied to the correction data creation tables B101A, B101B, B101C . That is, in the case of color unevenness correction, the present invention can also be applied to create correction data, which is stored in the correction data storage unit of the projector in advance, and further, the brightness unevenness correction data and color unevenness can also be Both correction data are stored in the projector in advance, and the projector is set up to be able to correct brightness unevenness and color unevenness at the same time.

In addition, in the second embodiment described above, correction data tables B101A, B101B, B101C, . That is, it can also be applied to self-luminous image display devices such as thin liquid crystal display devices, PDPs, and organic EL displays.

In addition, the specific structure, shape, etc. at the time of implementation of the present invention can be set as other structures within the scope of achieving the purpose of the present invention.

The present invention can be suitably used in image display devices such as PDPs and organic EL displays, in addition to projectors.

Claims (17)

1. A method for preparing a correction value of an image display device comprising an image display unit having a distribution in the output characteristic value of an image generating device paired with a screen displaying an image, and an image display unit for the above-mentioned output characteristic value The above-mentioned correction value of the image display device of the correction unit of the above-mentioned image display unit after the input image signal is corrected by distributing the corresponding correction value is characterized in that it includes: a step of detecting the distribution of the output characteristic value of the image displayed on the above-mentioned screen; A step of setting nodes within the output characteristic distribution according to the detected output characteristic distribution; a step of linking the set nodes with each other to divide the above image into a plurality of element regions; and Steps to set the correction value for each segmented feature area. 2. The correction value preparation method of the image display device according to claim 1, characterized in that: The steps for setting the above nodes include: An equipotential line interval setting step of setting intervals of equipotential lines connecting pixels with equal output characteristic values according to the distribution of detected output characteristic values; An isopotential line setting step for setting a plurality of isopotential lines according to the set isopotential line interval; and A node setting step for setting a plurality of nodes on each set equipotential line; The steps of segmenting the above image into multiple feature regions include: A division element setting step of dividing the image displayed on the above-mentioned screen into a plurality of element regions based on the set nodes. 3. The correction value creation method for an image display device according to claim 2, wherein: The steps for setting the equipotential interval above include: According to the distribution of the detected output characteristic values, the step of obtaining the part where the detected output characteristic value is farthest from the output characteristic value that should be displayed; and A step of setting the interval of equipotential lines in the vicinity of the detected portion to be narrower than that of other portions. 4. The correction value creation method for an image display device according to claim 3, wherein: The steps for setting the equipotential interval above include: a step of generating a histogram corresponding to the output characteristic value based on the detected distribution of the output characteristic value; and A step to narrow the interval of isopotential lines around the peak of the generated histogram. 5. The correction value preparation method of an image display device according to any one of claims 2 to 4, characterized in that: The above-mentioned output characteristic value is a luminance output value or a color output value of the above-mentioned image generating device. 6. The correction value creation method for an image display device according to claim 1, wherein: The steps for setting the above nodes include: An extremum setting step of setting a maximum or minimum extremum of the distribution of output characteristic values according to the distribution of the detected output characteristics; The steps of segmenting the above image into multiple feature regions include: A division element setting step that divides the image displayed on the above-mentioned screen into a plurality of element regions using the set extremum as a node. 7. The correction value preparation method of the image display device according to claim 6, characterized in that it comprises: After the step of setting the above-mentioned correction value, a post-correction distribution obtaining step of obtaining the distribution of the output characteristics of the image corrected with the prepared correction value; and The corrected image evaluation step is to judge whether the corrected image is good or bad based on the distribution of the corrected output characteristics, and if it is judged to be bad, the above-mentioned extreme value setting step to the above-mentioned correction value setting step are performed again. 8. The correction value preparation method for an image display device according to claim 7, characterized in that: In the extremum setting step performed again, a new extremum is added to the extremum set in the previous extremum setting step. 9. The correction value preparation method for an image display device according to any one of claims 6 to 8, characterized in that: The above-mentioned output characteristic value is a luminance output value or a color output value of the above-mentioned image generating device. 10. An image display device comprising an image display unit having a distribution in the output characteristic value of an image generating device paired with a screen displaying an image, and correcting an input image with a correction value corresponding to the distribution of the above-mentioned output characteristic value A correction unit for outputting the signal to the above-mentioned image display unit after being corrected, characterized in that, The correction unit above has: According to the distribution of the output characteristic value, a plurality of equipotential lines connecting pixels in the image displayed on the above-mentioned screen with the same output characteristic value are set, and the display at the The above-mentioned image on the screen is divided into a plurality of element areas, and a correction value storage unit stores a correction value for each divided element area; and A correction processing unit that corrects the input image signal for each of the element regions using the correction value stored in the correction value storage unit. 11. The image display device according to claim 10, characterized in that: The above-mentioned element area is a non-overlapping polygonal element area created by connecting nodes on the equipotential line with straight lines; The correction value storage unit includes: an element area storage table storing node position information indicating the position within the screen of each element area, and correction parameters for the element area specified by the node position information; and A correction value table stores correction values corresponding to the above-mentioned correction parameters. 12. The image display device according to claim 10 or 11, characterized in that: A plurality of correction values corresponding to different tone images are stored in the correction value storage unit. 13. The image display device according to claim 10 or 11, wherein the output characteristic value is a luminance output value or a color output value of the image generating device. 14. An image display device comprising an image display unit having a distribution in the output characteristic value of an image generating device paired with a screen displaying an image, and correcting an input image with a correction value corresponding to the distribution of the above-mentioned output characteristic value A correction unit for outputting the signal to the above-mentioned image display unit after being corrected, characterized in that, The correction unit above has: The distribution of the output characteristic value in the image displayed on the above-mentioned screen is set as the maximum or minimum extreme value of the output characteristic value as a node, and the image displayed on the above-mentioned screen is divided according to the set node dividing into a plurality of element areas, and storing a correction value storage unit for each divided element area; and A correction processing unit that corrects the input image signal for each of the element regions based on the correction value stored in the correction value storage unit. 15. The image display device according to claim 14, wherein: The correction value storage unit includes: an element area storage table storing node position information indicating the position within the screen of each element area, and correction parameters for the element area specified by the node position information; and A correction value table stores correction values corresponding to the above-mentioned correction parameters. 16. The image display device according to claim 14 or 15, characterized in that: A plurality of correction values corresponding to different tone images are stored in the correction value storage unit. 17. The image display device according to claim 14 or 15, characterized in that: The above-mentioned output characteristic value is a luminance output value or a color output value of the above-mentioned image generating device.

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