JP2006292914A - Image display device - Google Patents

Image display device Download PDF

Info

Publication number
JP2006292914A
JP2006292914A JP2005111807A JP2005111807A JP2006292914A JP 2006292914 A JP2006292914 A JP 2006292914A JP 2005111807 A JP2005111807 A JP 2005111807A JP 2005111807 A JP2005111807 A JP 2005111807A JP 2006292914 A JP2006292914 A JP 2006292914A
Authority
JP
Japan
Prior art keywords
light
image data
types
plurality
light emission
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP2005111807A
Other languages
Japanese (ja)
Other versions
JP5345271B2 (en
Inventor
Shuichi Kagawa
Hiroaki Sugiura
博明 杉浦
周一 香川
Original Assignee
Mitsubishi Electric Corp
三菱電機株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Electric Corp, 三菱電機株式会社 filed Critical Mitsubishi Electric Corp
Priority to JP2005111807A priority Critical patent/JP5345271B2/en
Publication of JP2006292914A publication Critical patent/JP2006292914A/en
Application granted granted Critical
Publication of JP5345271B2 publication Critical patent/JP5345271B2/en
Application status is Expired - Fee Related legal-status Critical
Anticipated expiration legal-status Critical

Links

Images

Abstract

PROBLEM TO BE SOLVED: To provide a plurality of types of light sources (5, 6) each emitting light having different spectral characteristics, and a light receiving type light modulation means for modulating illumination light from a plurality of types of light sources (5, 6) for each of a plurality of pixels. 8), it is possible to achieve desired good color reproduction without depending on the ratio of the emission intensities of a plurality of types of light sources.
A light emission ratio control means (4) for controlling a ratio of light emission intensities of a plurality of types of light sources (5, 6) based on first image data (R1, G1, B1) input from the outside, Color conversion means for correcting the color characteristics of the first image data (R1, G1, B1) based on the light emission ratio of the light sources (5, 6) and outputting the second image data (R2, G2, B2) ( 1), and the light receiving type light modulating means (4) modulates the illumination light from the light source (5, 6) based on the second image data (R2, G2, B2).
[Selection] Figure 1

Description

  The present invention relates to an image display device, and more particularly, to an image display device that displays an image using a light source and a light-receiving light modulation element, such as a liquid crystal display device.

An example of a conventional image display device and image display method is described in Patent Document 1 below. This conventional image display device and image display method is a liquid crystal display device having a backlight on the back of a liquid crystal panel, and both a cold cathode fluorescent lamp and a white or R, G, B light emitting diode array as a light source of the backlight. Alternatively, only the light emitting diode array is used, and the luminance is controlled by the light emitting diode. With this configuration, it is possible to realize video expression with a wide dynamic range and high-speed responsiveness of luminance of a display video without increasing power consumption. In addition, a diode corresponding only to an area in the vicinity of an image having a brightness equal to or higher than a threshold in the display screen is selectively controlled to further increase the brightness in the vicinity of the image.
JP2003-140110A

  In the image display device described above, when the light source has a plurality of types of light sources that emit light having different spectral characteristics, and the light emission intensity is controlled, illumination for irradiating the light receiving type light modulation means such as a liquid crystal panel according to the ratio of the light emission intensity The spectral characteristics of light change. As a result, there is a problem that the color reproduction characteristics of the display image change and the display is performed with an unexpected color.

  The present invention has been made in view of the above problems, and includes a plurality of types of light sources that emit light having different spectral characteristics, and a light reception that modulates illumination light from the plurality of types of light sources for each of a plurality of pixels. An object of the present invention is to provide an image display device having a desired light reproduction without depending on the ratio of the light emission intensities of the plurality of types of light sources.

  An image display apparatus according to the present invention includes a plurality of types of light sources that emit light having different spectral characteristics, and a light-receiving light modulation unit that modulates illumination light from the plurality of types of light sources for each of a plurality of pixels. In the image display device, a light emission ratio control means for controlling a ratio of light emission intensities of the plurality of types of light sources based on first image data inputted from the outside, and Color conversion means for correcting the color characteristics of the first image data and outputting second image data corresponding to the first image data, wherein the light receiving light modulation means is based on the second image data. The illumination light from the plurality of types of light sources is modulated.

  According to the present invention, it is possible to realize a desired good color reproduction without depending on the ratio of the emission intensity of the plurality of types of light sources.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing an embodiment of an image display apparatus according to the present invention. The image display apparatus shown in FIG. 1 includes a color conversion unit 1, a coefficient generation unit 2, and an image display unit 3. The image display unit 3 includes a light emission ratio control unit 4, a first light source 5, and a second light source. 6, illumination light diffusing means 7, and light receiving type light modulating means 8.

  The first image data R1, G1, and B1 are input to the color conversion unit 1 and the light emission ratio control unit 4. Here, R1, G1, and B1 are data representing red, green, and blue, respectively, for each pixel. The color conversion unit 1 performs color conversion processing on the first image data R1, G1, and B1 based on the color conversion coefficient from the coefficient generation unit 2 to generate second image data R2, G2, and B2. The color conversion unit 1 includes a matrix calculation circuit, a lookup table using a memory, and the like. When the color conversion means 1 is constituted by a matrix calculation circuit, the color conversion coefficient is given as a calculation coefficient (matrix coefficient) for matrix calculation. When the color conversion unit 1 is configured by a lookup table or the like, the color conversion coefficient is given as a table value.

  The light emission ratio control means 4 transmits the contents (for example, lightness distribution) of the first image data R1, G1, B1 over each screen, or a predetermined number preceding each screen and several past screens, for example, each screen. Based on the result of the analysis over the screen, the ratio of light emission of the first light source 5 and the second light source 6 when the screen is displayed is controlled. The ratio of light emission of the first light source 5 and the second light source 6 is controlled by the light emission intensity control data V1 and V2. The emission intensity control data V1 is data for controlling the emission intensity of the first light source 5, and the emission intensity control data V2 is data for controlling the emission intensity of the second light source 6. Light from the first light source 5 and the second light source 6 is diffused by the illumination light diffusion means 7 so as to uniformly illuminate the light receiving type light modulation means 8.

  The second image data R2, G2, and B2 are input to the light receiving type light modulation means 8. The light receiving type light modulating means 8 is constituted by a transmissive liquid crystal panel, for example, and changes the transmittance for each pixel based on the second image data R2, G2, B2. Thereby, the intensity of the illumination light diffused by the illumination light diffusing means 7 is modulated for each pixel to display an image.

  The first light source 5 and the second light source 6 emit light having different spectral characteristics. Here, the first light source 5 is a light source capable of displaying an image in a wide color reproduction range, and the second light source 6 is inferior in the color reproduction range, but has excellent luminous efficiency (that is, emits bright light). Possible light source. For example, the first light source 5 may have a configuration in which a plurality of light sources of different colors such as red, green, and blue light emitting diodes (LEDs) are arranged. On the other hand, the second light source 6 is constituted by a cold cathode fluorescent lamp or the like. In general, a light source using red, green, and blue LEDs has a spectrum concentrated near the dominant wavelength of each color and emits light with less unnecessary spectral components, so that it is possible to display an image in a wide color reproduction range. On the other hand, at present, the luminous efficiency of the LED is lower than that of the cold cathode fluorescent lamp, and the cold cathode fluorescent lamp is more advantageous for emitting bright light with the same power.

  FIG. 2 is a block diagram showing an example of the light emission ratio control means 4. The light emission ratio control means 4 shown in FIG. 2 includes a lightness calculation means 9, a histogram generation means 10, and a light emission ratio calculation means 11. The first image data R 1, G 1, B 1 are input to the brightness calculation means 9. The brightness calculation means 9 calculates and outputs the brightness L indicated by the first image data R1, G1, B1. The lightness L is calculated, for example, by weighted addition of the first image data R1, G1, and B1. At this time, the weight is determined by the magnitude of the contribution to the brightness of each color. The lightness L is input to the histogram generation means 10. The histogram generation means 10 generates, for example, a histogram D (L) representing the lightness L distribution of each pixel in one screen. The histogram D (L) represents the frequency of occurrence of the pixels having the lightness value in one screen for each value of the lightness L.

  The histogram D (L) is input to the light emission ratio calculation means 11. The light emission ratio calculation means 11 determines the light emission intensity control data V1 of the first light source 5 and the light emission intensity control data V2 of the second light source 6 according to the contents of the histogram D (L). For example, the center of gravity of the histogram D (L) is obtained, and the light emission intensity of the light source 6 increases when the center of gravity is in a region with a high brightness value, and the light emission intensity of the light source 5 is high when the center of gravity is in a region with a low brightness value. The emission intensity control data V1 and V2 are determined so that That is, when it is determined that the screen is a bright screen, the display is focused on brightness by increasing the light emission ratio of the cold cathode fluorescent lamp having higher luminous efficiency, and the screen is a relatively dark screen. If it is determined that the light emission ratio of the LED having a more excellent color reproduction range is increased, the color reproduction range is emphasized. This makes it possible to achieve both display brightness and color reproduction range. Here, instead of using the center of gravity of the histogram, the light emission ratio calculating means 11 may estimate the brightness of the screen using an average value, a cumulative frequency, or the like.

  FIG. 3 is a block diagram showing another example of the light emission ratio control means 4. The configuration of the light emission ratio control unit 4 shown in FIG. 3 is obtained by replacing the lightness calculation unit 9 with the saturation calculation unit 12 in the configuration shown in FIG. The saturation calculation unit 12 calculates and outputs the saturation S indicated by the first image data R1, G1, and B1. The saturation S is calculated using the maximum value and the minimum value of the first image data R1, G1, B1, for example. The saturation S is input to the histogram generation means 10 and a histogram D (S) is generated for each screen. The light emission ratio calculation means 11 determines the light emission intensity control data V1 and V2 according to the contents of the histogram D (S). Is done. The above operation is the same as that in FIG. In the configuration of the light emission ratio control means 4 shown in FIG. 3, when it is determined that the screen is a vivid screen with high saturation, the light emission ratio of the LED having a more excellent color reproduction range is increased. If the display is focused on the color reproduction range and the screen is determined to be a relatively low-saturation screen, the power consumption can be reduced by increasing the emission ratio of the cold cathode fluorescent lamp with better luminous efficiency. Display with emphasis on. Thereby, both low power consumption and a color reproduction range can be achieved.

  Next, the operation in the coefficient generating means 2 will be described. The coefficient generation means 2 receives light emission intensity control data V1 and V2. The coefficient generating means 2 obtains a light emission ratio from the light emission intensity control data V1 and V2, and generates a color conversion coefficient based on the obtained light emission ratio. Here, if the color conversion processing in the color conversion means 1 is expressed by the following equation (1), the color conversion coefficient is expressed by a matrix coefficient (Aij). The matrix coefficient (Aij) is a 3 × 3 matrix with i = 1 to 3 and j = 1 to 3.

  FIG. 4 is a block diagram showing an example of the coefficient generation means 2. The coefficient generation means 2 shown in FIG. 4 includes a light emission ratio calculation means 13, coefficient storage means 14a to 14e, a coefficient selection means 15, and a coefficient interpolation means 16. The light emission intensity control data V 1 and V 2 are input to the light emission ratio calculation means 13. The light emission ratio calculation means 13 calculates a normalized light emission ratio a that is a normalized light emission ratio of the first light source 5. The normalized emission ratio is normalized to be 1 when the emission ratios of the first light source 5 and the second light source 6 are added. Therefore, the normalized emission ratio of the second light source 6 is (1− a). The normalized light emission ratio a is input to the coefficient selection unit 15 and the coefficient interpolation unit 16.

  The coefficient storage units 14a to 14e each store in advance a color conversion coefficient for a representative value of the normalized light emission ratio a. The coefficient storage means 14a is a color conversion coefficient for the normalized emission ratio a = a0 = 0, the coefficient storage means 14b is a color conversion coefficient for the normalized emission ratio a = a1 = 0.25, and the coefficient storage means 14c is normalized. The color conversion coefficient for the light emission ratio a = a2 = 0.5, the coefficient storage means 14d is the color conversion coefficient for the normalized light emission ratio a = a3 = 0.75, and the coefficient storage means 14e is the normalized light emission ratio a = a4 = The color conversion coefficient for 1 is stored. Each color conversion coefficient has a different value.

  As the light emission ratio changes, the spectral characteristics of the illumination light from the light source that illuminates the light-receiving light modulation means 8 change. Therefore, if the modulation in the light receiving type light modulating means 8 is the same (that is, the value of the second image data is the same), the spectral characteristic (that is, the displayed color) of the light after the modulation changes. Therefore, in order for the displayed colors to be the same, the value of the second image data needs to change according to the light emission ratio of the light source. That is, in order for the same color to be displayed for the same first image data value, the corresponding second image data value needs to change according to the light emission ratio of the light source. In other words, the color conversion coefficient for generating the second image data from the first image data needs to change according to the light emission ratio of the light source. Here, the same displayed colors are not necessarily limited to those having the same spectral characteristics, but include that the colorimetric or visual difference is within an allowable range.

The coefficient selection unit 15 selects two appropriate sets of color conversion coefficients stored in the coefficient storage units 14a to 14e based on the value of the normalized light emission ratio a output from the light emission ratio calculation unit 13. Output as (Dij) and (Eij). Here, as the appropriate two sets of color conversion coefficients (Dij) and (Eij), the color conversion coefficients for the two values (two of a0 to a4) closest to the input normalized light emission ratio a are used. Is selected.
For example, when the normalized emission ratio a = 0.6, the coefficient stored in the coefficient storage unit 14c, which is a color conversion coefficient for the normalized emission ratio a = a2 = 0.5, is (Dij) A coefficient stored in the coefficient storage unit 14d, which is a color conversion coefficient for the normalized emission ratio a = a3 = 0.75, is selected as (Eij).

The coefficient interpolation means 16 calculates a color conversion coefficient (Aij) corresponding to the value of the input normalized light emission ratio a from the two selected color conversion coefficients (Dij) and (Eij). For example, the value of each element of the color conversion coefficient (Aij) is obtained by weighted addition of the values of each element of (Dij) and (Eij). The weighting at this time is determined according to the distance between the input normalized emission ratio a and the normalized emission ratio corresponding to the selected coefficient.
If the normalized light emission ratio a output from the light emission ratio calculating means 13 is equal to ai (i = 0, 1, 2, 3, 4), a color conversion coefficient for ai and a (i + 1) or Select a color conversion coefficient for a (i-1). In this case, in weighted addition, 1 is applied to the color conversion coefficient for ai, and 0 is applied to the color conversion coefficient for a (i + 1) or a (i-1).

  The image display apparatus in the present embodiment operates as described above. Therefore, by changing the light emission ratio of multiple types of light sources that emit light having different spectral characteristics depending on the content of the image, for example, it is possible to achieve both display brightness or low power consumption and a wide color reproduction range. It becomes. In addition, since the characteristics of color conversion are determined based on the light emission ratios of a plurality of types of light sources, it is possible to realize desired good color reproduction without depending on the light emission ratios of the plurality of types of light sources.

Embodiment 2. FIG.
FIG. 5 is a block diagram showing another embodiment of the image display device according to the present invention. The image display apparatus shown in FIG. 5 includes a color conversion unit 1, a coefficient generation unit 2b, and an image display unit 3b. The image display unit 3b includes a light emission ratio control unit 4b, an R light source 17, a G light source 18, and a B light source. 19, illumination light diffusing means 7, and light receiving type light modulating means 8. The configuration other than the coefficient generation means 2b, the light emission ratio control means 4b, the R light source 17, the G light source 18, and the B light source 19 is the same as that shown in FIG.

  The first image data R1, G1, and B1 are input to the color conversion unit 1 and the light emission ratio control unit 4b. The color conversion unit 1 performs color conversion processing on the first image data R1, G1, and B1 based on the color conversion coefficient from the coefficient generation unit 2b to generate second image data R2, G2, and B2. When the color conversion means 1 is composed of a matrix calculation circuit, the color conversion coefficient is given as a calculation coefficient for matrix calculation. When the color conversion unit 1 is configured by a lookup table or the like, the color conversion coefficient is given as a table value.

The light emission ratio control means 4b provides the contents of the first image data R1, G1, B1 (for example, distribution of color components) over each screen or each screen and several past screens, for example, a predetermined preceding each screen. Based on the results of the analysis, the ratio of the light emission of the R light source 17, the G light source 18 and the B light source 19 when the screen is displayed is controlled. The light emission ratios of the R light source 17, the G light source 18, and the B light source 19 are controlled by the light emission intensity control data VR, VG, and VB. The emission intensity control data VR is data for controlling the emission intensity of the R light source 17, the emission intensity control data VG is data for controlling the emission intensity of the G light source 18, and the emission intensity control data VB is B. This is data for controlling the light emission intensity of the light source 19.
The R light source 17, the G light source 18, and the B light source 19 emit red, green, and blue light, respectively (that is, emit light having different spectral characteristics). The R light source 17, the G light source 18, and the B light source 19 can be configured by, for example, red, green, and blue light emitting diodes (LEDs).

Light from the R light source 17, the G light source 18, and the B light source 19 is diffused by the illumination light diffusing unit 7 so as to uniformly illuminate the light receiving type light modulating unit 8.
The second image data R2, G2, and B2 are input to the light receiving type light modulation means 8. The light receiving type light modulating means 8 is constituted by a transmissive liquid crystal panel, for example, and changes the transmittance for each pixel based on the second image data R2, G2, B2. Thereby, the intensity of the illumination light diffused by the illumination light diffusing means 7 is modulated for each pixel to display an image.

  FIG. 6 is a block diagram showing an example of the light emission ratio control means 4b. The light emission ratio control unit 4b illustrated in FIG. 6 includes a chromatic color component calculation unit 20, a histogram generation unit 10b, and a light emission ratio calculation unit 11b. The first image data R 1, G 1, B 1 is input to the chromatic color component calculation means 20. The chromatic color component calculation means 20 calculates and outputs chromatic color component data r, g, b representing the chromatic color component in the first image data R1, G1, B1. The chromatic color component data r, g, and b are obtained by the following equation (2), for example.

  In Expression (2), α is the minimum value of the first image data R1, G1, and B1, and represents an achromatic component in the first image data R1, G1, and B1. The chromatic color component data r, g, b is input to the histogram generation means 10b. The histogram generation unit 10b generates, for example, histograms D (r), D (g), and D (b) representing the distribution of chromatic color component data r, g, and b in one screen for each screen. Histograms D (r), D (g), and D (b) represent the occurrence frequency within one screen of pixels having the values for each value of chromatic color component data r, g, and b.

  The histograms D (r), D (g), and D (b) are input to the light emission ratio calculation unit 11b. The light emission ratio calculating means 11b is configured to emit light intensity control data VR of the R light source 17, light emission intensity control data VG of the G light source 18, and B light source according to the contents of the histograms D (r), D (g), D (b). 19 emission intensity control data VB are determined. For example, the respective centroids of the histograms D (r), D (g), and D (b) are obtained, and the emission intensity of the R light source 17 is increased when the centroid of the histogram D (r) is larger than the others. When the center of gravity of the histogram D (b) is higher than the others, the emission intensity of the G light source 18 becomes stronger when the center of gravity of the histogram D (b) is higher than the others. The emission intensity control data VR, VG, and VB are determined so as to increase. In other words, when it is determined that the screen is a strong red screen as a whole, the display is made by increasing the light emission ratio of the R light source 17 to improve the red reproducibility, and the screen is a strong green screen as a whole. If it is determined that the light emission ratio of the G light source 18 is increased to improve the green reproducibility, and if it is determined that the screen is a strong blue screen as a whole, The light emission ratio of the light source 19 is increased so that the display is improved in blue reproducibility. As a result, the color reproducibility of the display image can be improved.

When the light-receiving type light modulation means 8 is a color liquid crystal panel, each pixel is provided with a color filter. Generally, the color filter tends to transmit light having a wavelength other than the transmission band. Further, in order to perform bright display with low power consumption, the transmission band of the color filter is often very wide. Therefore, the light that has passed through the color filter often transmits some light that is originally unnecessary (not to be transmitted).
In the image display device of the present embodiment, for example, when the light emission ratio of the R light source 17 is made higher than the others, the illumination light that illuminates the light-receiving light modulating means 8 is in the green and blue regions (short to medium wavelength). The wavelength component becomes relatively small. As a result, the red color that is displayed after being modulated by the light receiving type light modulating means 8 is displayed as a red having a higher purity because unnecessary wavelength components are reduced. As a result, there is an effect that the reproducibility of red is very high. The same applies to green and blue.
Here, instead of using the center of gravity of the histogram, the light emission ratio calculating means 11b may use an average value or a cumulative frequency.

  Next, the operation in the coefficient generating means 2b will be described. The coefficient generation means 2b receives light emission intensity control data VR, VG, VB. In the coefficient generation means 2b, a light emission ratio is obtained from the light emission intensity control data VR, VG, VB, and a color conversion coefficient is generated based on the obtained light emission ratio. Here, even in the case of a strong red screen, for example, there are generally green and blue pixels in the screen. At this time, when the light emission ratio of the R light source 17 is higher than the others, unnecessary wavelength components are reduced for pixels that display red, while they are unnecessary for display of green and blue pixels. The wavelength component (red) increases and color reproducibility deteriorates. The coefficient generating means 2b generates a coefficient that reduces unnecessary color components from the image signal for pixels whose unnecessary wavelength components increase and color reproducibility deteriorates by changing the light emission ratio of the light source. .

  When the emission ratio of the R light source 17 is higher than the others, a coefficient for reducing the red component in the image signal is generated for the display of the green and blue pixels. In other words, if the first image data R1, G1, B1 represents green or blue, a coefficient is generated so that the ratio of R2 in the second image data R2, G2, B2 is small. Here, if the color conversion processing in the color conversion means 1 is expressed by the following equation (3), the color conversion coefficient is expressed by a matrix coefficient (Aij).

  In the above equation (3), a11, a21, and a31 are coefficients that determine the ratio of the second image data R2, G2, and B2, respectively, when the first image data represents red, and a12, a22, and a32 are the first. Coefficients for determining the ratio of the second image data R2, G2, and B2 when one image data represents green, a13, a23, and a33 are the second image data when the first image data represents blue It is a coefficient that determines the ratio of R2, G2, and B2, respectively. Accordingly, in the light emission ratio obtained from the light emission intensity control data VR, VG, VB, for example, when the light emission ratio of the R light source 17 is higher than the others, the coefficient generating means 2b generates coefficients with the values of a12 and a13 made smaller. .

  The color conversion process in the color conversion unit 1 may be a process represented by the following expression (4) instead of the above expression (3). In equation (4), the matrix coefficient (Hij) is the color conversion coefficient generated by the coefficient generating means 2b. In Expression (4), α is the minimum value of the first image data R1, G1, B1, and represents an achromatic component in the first image data R1, G1, B1.

  According to the above equation (4), it is possible to adjust achromatic color reproduction in addition to red, blue, and green color reproduction. In the above equation (4), h14, h24, and h34 are coefficients that respectively determine the ratios of the second image data R2, G2, and B2 when the first image data represents an achromatic color. According to the color conversion process of the above formula (4), it is possible to improve the color reproduction of achromatic colors such as white on a strong red screen. When the light emission ratio of the R light source 17 is higher than the others, the reproduction of achromatic colors such as white has a strong redness. Therefore, the coefficient generating means 2b reduces the ratio of the second image data R2 when the first image data R1, G1, B1 represents an achromatic color by decreasing the value of d14. This eliminates the intensity of the achromatic red color displayed.

  Furthermore, the color conversion process in the color conversion unit 1 may be a process represented by the following formula (5) instead of the above formula (3) or formula (4). In equation (5), the matrix coefficient (Kij) is the color conversion coefficient generated by the coefficient generating means 2b. In the formula (5), hr, hg, hb, hc, hm, and hy are calculation terms that are effective only for the hues of red, green, blue, cyan, yellow, and magenta, respectively, and the first color data R1, It is generated from G1 and B1. α is the minimum value of the first image data R1, G1, B1, and represents an achromatic component in the first image data R1, G1, B1.

  According to the above equation (5), by adjusting the value of the matrix coefficient related to each calculation term, the six hues of red, blue, green, cyan, yellow, and magenta, and achromatic color reproduction can be independently performed. It becomes possible to adjust to. When the light emission ratio of the R light source 17 is higher than the others, the color reproduction of the adjacent yellow and magenta becomes strong reddish. Can be adjusted independently of the red color reproduction, and the redness of the displayed yellow and magenta can be eliminated.

  The image display apparatus in the present embodiment operates as described above. Therefore, the light emission ratios of a plurality of types of light sources that emit light of different colors according to the contents of the image are changed, and the characteristics of color conversion are determined based on the light emission ratios of the light sources, so that good color reproduction can be realized. Is possible.

It is a block diagram which shows the image display apparatus of Embodiment 1 of this invention. It is a block diagram which shows an example of an internal structure of a light emission ratio control means. It is a block diagram which shows an example of an internal structure of a light emission ratio control means. It is a block diagram which shows an example of an internal structure of a coefficient generation means. It is a block diagram which shows the image display apparatus of Embodiment 2 of this invention. It is a block diagram which shows an example of an internal structure of a light emission ratio control means.

Explanation of symbols

1 color conversion means, 2, 2b coefficient generation means, 3 image display means, 4, 4b emission ratio control means, 5 first light source, 6 second light source, 7 illumination light diffusion means, 8 light receiving light modulation means, 9 Lightness calculation means 10, 10b Histogram generation means 11, 11b Light emission ratio calculation means, 12 Saturation calculation means, 13 Light emission ratio calculation means, 14a to 14e Coefficient storage means, 15 Coefficient selection means, 16 Coefficient interpolation means, 17 R light source, 18 G light source, 19 B light source, 20 chromatic color component calculating means.

Claims (8)

  1. Multiple types of light sources that emit light with different spectral characteristics,
    In an image display apparatus comprising: a light receiving type light modulating means for modulating illumination light from the plurality of types of light sources for each of a plurality of pixels provided;
    A light emission ratio control means for controlling a ratio of light emission intensities of the plurality of types of light sources based on first image data input from the outside;
    Color conversion means for correcting the color characteristics of the first image data based on the light emission ratios of the plurality of types of light sources and outputting second image data corresponding to the first image data;
    An image display device, wherein the light receiving type light modulating means modulates illumination light from the plurality of types of light sources based on the second image data.
  2.   The image display apparatus according to claim 1, wherein the plurality of types of light sources include a cold cathode fluorescent lamp and a light emitting diode.
  3.   The image display apparatus according to claim 1, wherein the plurality of types of light sources include light emitting diodes of different colors.
  4.   The image display device according to claim 3, wherein the plurality of types of light sources include red, green, and blue light emitting diodes.
  5.   The said light emission ratio control means controls the ratio of the light emission intensity of the said multiple types of light source based on the brightness distribution of the said 1st image data, The any one of Claims 1-4 characterized by the above-mentioned. Image display device.
  6.   The light emission ratio control means analyzes the brightness distribution of the first image data over each screen or over each screen and a predetermined number of screens preceding each screen, and based on the result of the analysis The image display device according to claim 5, wherein a ratio of emission intensity of the plurality of types of light sources when the screen is displayed is controlled.
  7.   The light emission ratio control means controls a ratio of light emission intensities of the plurality of types of light sources based on a distribution of color components of the first image data. The image display device described.
  8.   The light emission ratio control means analyzes the distribution of the color components of the first image data over each screen, or over each screen and a predetermined number of screens preceding each screen. The image display device according to claim 7, wherein the ratio of the emission intensity of the plurality of types of light sources when the screen is displayed is controlled based on the screen.
JP2005111807A 2005-04-08 2005-04-08 Image display device Expired - Fee Related JP5345271B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2005111807A JP5345271B2 (en) 2005-04-08 2005-04-08 Image display device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2005111807A JP5345271B2 (en) 2005-04-08 2005-04-08 Image display device

Publications (2)

Publication Number Publication Date
JP2006292914A true JP2006292914A (en) 2006-10-26
JP5345271B2 JP5345271B2 (en) 2013-11-20

Family

ID=37413578

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2005111807A Expired - Fee Related JP5345271B2 (en) 2005-04-08 2005-04-08 Image display device

Country Status (1)

Country Link
JP (1) JP5345271B2 (en)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006323130A (en) * 2005-05-19 2006-11-30 Hitachi Displays Ltd Image display device and image display method
JP2007322944A (en) * 2006-06-03 2007-12-13 Sony Corp Display control device, display device, and display control method
JP2010518441A (en) * 2007-02-13 2010-05-27 コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ Improved display apparatus and method
WO2010064474A1 (en) * 2008-12-01 2010-06-10 シャープ株式会社 Backlight unit, liquid crystal display device, data generating method, data generating program and recording medium
JP2010530986A (en) * 2007-06-13 2010-09-16 トムソン ライセンシングThomson Licensing Image display device with two adjustment stages
JP2012150149A (en) * 2011-01-17 2012-08-09 Mitsubishi Electric Corp Multiscreen display device
WO2013080488A1 (en) * 2011-11-28 2013-06-06 パナソニック株式会社 Display apparatus
US8525823B2 (en) 2011-03-24 2013-09-03 Kabushiki Kaisha Toshiba Liquid crystal display device
JP2013536956A (en) * 2010-08-30 2013-09-26 クゥアルコム・インコーポレイテッドQualcomm Incorporated Adaptive color correction for displays with backlight modulation
JP2014132350A (en) * 2008-06-30 2014-07-17 Intel Corp Method and apparatus for reducing power consumption for displays
JP2014182192A (en) * 2013-03-18 2014-09-29 Canon Inc Image display device and control method thereof
JP2017076094A (en) * 2015-10-16 2017-04-20 株式会社デンソー Liquid crystal display

Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01158416A (en) * 1987-12-16 1989-06-21 Stanley Electric Co Ltd Brightness adjusting device for color display
JPH09113871A (en) * 1995-10-17 1997-05-02 Sony Corp Liquid crystal display device
JPH10282470A (en) * 1997-04-11 1998-10-23 Matsushita Electric Ind Co Ltd Liquid crystal display device
JPH11296127A (en) * 1998-04-07 1999-10-29 Hitachi Ltd Liquid crystal display device
JP2001135118A (en) * 1999-11-02 2001-05-18 Toshiba Corp Panel light source device and flat display using the same
JP2002014660A (en) * 2000-06-29 2002-01-18 Victor Co Of Japan Ltd Liquid crystal display device
JP2002099250A (en) * 2000-09-21 2002-04-05 Toshiba Corp Display device
JP2002202762A (en) * 2000-12-28 2002-07-19 Seiko Epson Corp Liquid crystal display device, drive circuit, drive method and electronic equipment
JP2003140110A (en) * 2001-08-20 2003-05-14 Hitachi Device Eng Co Ltd Liquid crystal display device and its drive circuit
JP2003295154A (en) * 2002-03-29 2003-10-15 Fuji Photo Film Co Ltd Method of adjusting monochrome lcd color and medical image display device
JP2003331608A (en) * 2002-03-05 2003-11-21 Sharp Corp Light emitting device and display device using same
JP2004012519A (en) * 2002-06-03 2004-01-15 Seiko Epson Corp Image display, image displaying method and computer-readable recording medium with image display program recorded thereon
JP2004151672A (en) * 2002-09-04 2004-05-27 Sharp Corp Liquid crystal display device
JP2004325629A (en) * 2003-04-23 2004-11-18 Seiko Epson Corp Display device and its dimming method
JP2006039520A (en) * 2004-06-21 2006-02-09 Hitachi Displays Ltd Liquid crystal display apparatus

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01158416A (en) * 1987-12-16 1989-06-21 Stanley Electric Co Ltd Brightness adjusting device for color display
JPH09113871A (en) * 1995-10-17 1997-05-02 Sony Corp Liquid crystal display device
JPH10282470A (en) * 1997-04-11 1998-10-23 Matsushita Electric Ind Co Ltd Liquid crystal display device
JPH11296127A (en) * 1998-04-07 1999-10-29 Hitachi Ltd Liquid crystal display device
JP2001135118A (en) * 1999-11-02 2001-05-18 Toshiba Corp Panel light source device and flat display using the same
JP2002014660A (en) * 2000-06-29 2002-01-18 Victor Co Of Japan Ltd Liquid crystal display device
JP2002099250A (en) * 2000-09-21 2002-04-05 Toshiba Corp Display device
JP2002202762A (en) * 2000-12-28 2002-07-19 Seiko Epson Corp Liquid crystal display device, drive circuit, drive method and electronic equipment
JP2003140110A (en) * 2001-08-20 2003-05-14 Hitachi Device Eng Co Ltd Liquid crystal display device and its drive circuit
JP2003331608A (en) * 2002-03-05 2003-11-21 Sharp Corp Light emitting device and display device using same
JP2003295154A (en) * 2002-03-29 2003-10-15 Fuji Photo Film Co Ltd Method of adjusting monochrome lcd color and medical image display device
JP2004012519A (en) * 2002-06-03 2004-01-15 Seiko Epson Corp Image display, image displaying method and computer-readable recording medium with image display program recorded thereon
JP2004151672A (en) * 2002-09-04 2004-05-27 Sharp Corp Liquid crystal display device
JP2004325629A (en) * 2003-04-23 2004-11-18 Seiko Epson Corp Display device and its dimming method
JP2006039520A (en) * 2004-06-21 2006-02-09 Hitachi Displays Ltd Liquid crystal display apparatus

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006323130A (en) * 2005-05-19 2006-11-30 Hitachi Displays Ltd Image display device and image display method
JP2007322944A (en) * 2006-06-03 2007-12-13 Sony Corp Display control device, display device, and display control method
JP2010518441A (en) * 2007-02-13 2010-05-27 コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ Improved display apparatus and method
JP2010530986A (en) * 2007-06-13 2010-09-16 トムソン ライセンシングThomson Licensing Image display device with two adjustment stages
KR101532309B1 (en) * 2007-06-13 2015-07-09 톰슨 라이센싱 Device for displaying images comprising two modulation stages
JP2014132350A (en) * 2008-06-30 2014-07-17 Intel Corp Method and apparatus for reducing power consumption for displays
WO2010064474A1 (en) * 2008-12-01 2010-06-10 シャープ株式会社 Backlight unit, liquid crystal display device, data generating method, data generating program and recording medium
US9478173B2 (en) 2010-08-30 2016-10-25 Qualcomm Incorporated Adaptive color correction for display with backlight modulation
JP2013536956A (en) * 2010-08-30 2013-09-26 クゥアルコム・インコーポレイテッドQualcomm Incorporated Adaptive color correction for displays with backlight modulation
JP2012150149A (en) * 2011-01-17 2012-08-09 Mitsubishi Electric Corp Multiscreen display device
US8801196B2 (en) 2011-01-17 2014-08-12 Mitsubishi Electric Corporation Multi-screen display apparatus that determines common target brightness for controlling multiple light sources
US8525823B2 (en) 2011-03-24 2013-09-03 Kabushiki Kaisha Toshiba Liquid crystal display device
JPWO2013080488A1 (en) * 2011-11-28 2015-04-27 パナソニックIpマネジメント株式会社 display device
WO2013080488A1 (en) * 2011-11-28 2013-06-06 パナソニック株式会社 Display apparatus
US9400347B2 (en) 2011-11-28 2016-07-26 Panasonic Intellectual Property Management Co., Ltd. Display device
JP2014182192A (en) * 2013-03-18 2014-09-29 Canon Inc Image display device and control method thereof
JP2017076094A (en) * 2015-10-16 2017-04-20 株式会社デンソー Liquid crystal display

Also Published As

Publication number Publication date
JP5345271B2 (en) 2013-11-20

Similar Documents

Publication Publication Date Title
JP5301161B2 (en) Field sequential display of color images
JP5368499B2 (en) Color display apparatus and method for improving attributes
TWI330270B (en) Region-based displayer and display method thereof
KR101135339B1 (en) Color liquid crystal display
US8605017B2 (en) High dynamic contrast display system having multiple segmented backlight
US6961038B2 (en) Color liquid crystal display device
ES2700874T3 (en) Apparatus and methods for color display devices
JP4979776B2 (en) Image display device and image display method
TW589614B (en) Adaptive contrast and brightness enhancement with color preservation
KR101614405B1 (en) Four-channel display power reduction with desaturation
JP4818351B2 (en) Image processing apparatus and image display apparatus
JP2006284981A (en) Image display device, method, and program
CN1882103B (en) Systems and methods for implementing improved gamut mapping algorithms
JP5611508B2 (en) Ambient light adaptive color correction apparatus and method
US7486304B2 (en) Display device with dynamic color gamut
JP2005309338A (en) Apparatus and method for image display
US8004545B2 (en) Display apparatus with arrangement to decrease quantity of backlight and increase transmittance of the display panel
JP4856249B2 (en) Display device
JP2009500654A (en) Method and apparatus for converting signals for driving a display, and display using the method and apparatus
US20100103187A1 (en) Method of color gamut mapping of color input values of input image pixels of an input image to rgbw output values for an rgbw display, display module, and apparatus using such method
TWI393113B (en) Methods of converting a three-or-more component image input signal to an image output signal and displaying the image input signal on a display device, and four-color display
RU2599364C2 (en) Polychromatic solid-state light sources for chroma control of illuminated surfaces
CN103080999B (en) For having the self-adaptation color correction of the indicating meter of backlight modulation
US8872861B2 (en) Apparatus for selecting backlight color values
EP2023642A1 (en) Color image display device and color conversion device

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20071207

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20101220

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20110111

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20110304

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20120403

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20120531

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20130319

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20130425

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20130813

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20130814

R150 Certificate of patent or registration of utility model

Free format text: JAPANESE INTERMEDIATE CODE: R150

LAPS Cancellation because of no payment of annual fees