JP2010066537A - Electrooptical apparatus and electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrooptical apparatus capable of suitably performing color modulation and intensity modulation. <P>SOLUTION: The electrooptical apparatus (1) has: an organic EL panel (10) which adjusts the color of an image to be displayed on the basis of color information included in an input image signal; and a liquid crystal panel (20) which adjusts the brightness of the image on the basis of brightness information included in the input image signal. The organic EL panel and the liquid crystal panel include organic EL substances which emit light and liquid crystals which adjust light transmittance, respectively. By this configuration, the electrooptical apparatus displays, as it were, one image as a whole, wherein the color modulation of the image is performed by the organic EL panel and intensity modulation is performed by the liquid crystal panel. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electro-optical device and an electronic apparatus including an electro-optical material such as an organic EL material and liquid crystal.

Conventionally, liquid crystal displays, organic EL displays, plasma displays, field emission displays, and the like have been proposed as thin displays.
Among these, the liquid crystal display has a liquid crystal element having a structure in which a liquid crystal layer containing liquid crystal molecules is sandwiched between two electrodes facing each other. When an appropriate potential difference is set between the two electrodes, the alignment state of the liquid crystal molecules changes, thereby changing the ratio (transmittance) of light transmitted through the liquid crystal element. Light in this case (that is, light for irradiating the liquid crystal element) is emitted from a light source prepared separately from the liquid crystal element.
If such liquid crystal elements are arranged in a matrix and the light transmittance of each liquid crystal element is appropriately controlled, an image having a desired meaning can be displayed. Further, if color filters such as red (R), green (G), and blue (B) are provided in an appropriate arrangement mode while appropriately corresponding to each liquid crystal element, a color image can be displayed. Display is also possible.
As such a liquid crystal display, for example, a liquid crystal display as disclosed in Patent Document 1 is known.
JP 2006-91475 A

By the way, the liquid crystal display as described above has a problem that the colorful environment cannot be sufficiently reproduced, or there is still room for improvement in improving the coloring performance of an image to be displayed.
For example, the above-described color image display using the color filter includes adjusting the light transmittance of each liquid crystal element corresponding to each color filter (for example, R filter, G filter, and B filter), and so-called additive color mixing. It is done by using the principle of. In this case, when three liquid crystal elements corresponding to the R filter, the G filter, and the B filter are set as one set (that is, one pixel) and a certain color is to be expressed, the transmittance is expressed by a specific constant. The drive control of the liquid crystal element, such as setting to some α [%], β [%], and γ [%], is performed.
However, in this case, the loss of light for 100-α [%], 100-β [%] and 100-γ [%], that is, a decrease in brightness (or luminance) is inevitably required. It can be said that it accompanies. That is, in color image display in such a case, generally, if modulation from one color to another color is performed, the brightness is sacrificed to adjust the hue, or the hue is merely adjusted to adjust the brightness. (For example, the above-mentioned values of α to γ are specifically set to reduce the brightness, but the entire display image has been bluish unexpectedly.) Can occur.)

In short, in the simple coloration mode adjustment using only the color filter, both the brightness and the hue are adjusted only by adjusting the amount of light transmitted through the color filter. If this is the case, there is always a risk that the other request will not be satisfied.
Such a problem is more or less applicable to the various displays described above, and is not limited to a liquid crystal display.

  The above-mentioned patent document 1 teaches a method for coping with such a problem. That is, Patent Document 1 is based on the premise that “a plurality of light modulation elements” are provided, and “control values of light modulation elements forming a luminance panel” and “control values of light modulation elements forming a color panel” are included. Disclosed is a technique separately obtained (see, for example, [Claim 3] of Patent Document 1). As described above, if the luminance and the color are modulated by using separate “light modulation elements”, the above-described problems can be overcome to a considerable extent.

  However, there is still room for improvement in such a technique. For example, in the above-described configuration, the “light modulation element forming the color panel” is configured by “liquid crystal light valve 31, 32, 33” (see [0027] or [FIG. 1] of Patent Document 1). In this case, the light modulation element requires a light source (hereinafter referred to as “backlight”) separately as described above. In this case, if this backlight emits completely white light with no bias, no major problem will occur. However, in practice, it is normal to emit light having a certain bias with respect to the wavelength component contained therein. It is. On the other hand, the ratio of light passing through the liquid crystal is generally different for each wavelength. That is, the light transmittance in the liquid crystal has wavelength dependency.

Then, due to the effects of both, there is a high possibility that the degree of modulation may not be performed as expected depending on the “light modulation element” composed of “liquid crystal light valves 31, 32, 33”. For example, as described above, even if the light transmittances α [%], β [%], and γ [%] are set corresponding to R, G, and B, respectively, the bias effect of the backlight is assumed to be about B. In the case where Δβ [%] is expected, the same situation is created as when the transmittance is set to α [%], (β + Δβ) [%], γ [%].
As a result, in the end, the expression or reproduction of the correct color tone is impaired, or the expression or reproduction of the accurate luminance is also impaired (the aforementioned “control value of the light modulation element forming the luminance panel” is expressed by “α This is because [%], β [%], and γ [%] ”are supposed to be calculated)).

In this regard, as described above, not only in the simple case where only the addition of Δβ needs to be considered, but also in consideration of the fact that the actual backlight may exhibit more complicated light emission behavior, etc., gamma correction It is conceivable to solve the above-mentioned problems by carefully performing various correction processes such as the above, and carefully addressing the above-described problems. However, such a measure certainly requires extra computation or control, and thus it is inevitable to cause a new problem of longer processing time or higher cost.
Further, the light transmittance in the liquid crystal has not only the above-described wavelength dependency but also temperature dependency. That is, there is a high possibility that the light transmittance will change large or small depending on the use environment temperature of the display.
Taking this into consideration, it is not always a realistic and appropriate countermeasure to perform the various correction processes described above (in particular, relying solely on them) in order to deal with the differences in these situations one by one. That's not true.

  An object of the present invention is to provide an electro-optical device that can solve at least a part of the above-described problems and an electronic apparatus including the same.

  In order to solve the above-described problems, an electro-optical device according to the present invention includes first and second electro-optical panels including an electro-optical material that changes its optical characteristics when a predetermined potential or current is applied. An electro-optical device comprising: a signal separating unit that calculates color information and luminance information supplied to each of the first and second electro-optical panels based on an input image signal; The electro-optical material included in the second electro-optical material includes an organic EL (electro luminescent) material, the electro-optical material included in the second electro-optical panel includes liquid crystal, and the first electro-optical panel includes the color information. And adjusting the color of an image to be displayed, and the second electro-optical panel transmits, reflects, or blocks all or part of the light emitted from the first electro-optical panel. Meanwhile, the brightness of the image is adjusted based on the brightness information.

According to the present invention, on the assumption that two panels, the first and second electro-optical panels, are provided, the first electro-optical panel performs only adjustment or modulation of chromaticity or color in a pure sense, Since the second electro-optical panel can only adjust or modulate the luminance, the luminance can be sufficiently adjusted while sufficiently performing color reproduction. That is, according to the present invention, there is almost no need to worry about the occurrence of such an event that the brightness is sacrificed in order to adjust the hue, and the hue is lost while only the brightness is desired to be adjusted.
Further, according to this configuration, according to the present invention, it is possible to perform color adjustment and luminance adjustment more delicately, or to increase the contrast ratio of an image. The former is because, for example, it is possible to use different bit strings in order to express color and luminance (as in the above-described conventional example, adjustment of color and luminance can be performed with one electro-optical panel. When performing, for example, one bit string needs to be divided and used with the two types of information, but in the present invention, such consideration is not necessary in principle.) The latter is theoretically because the product of the contrast ratios of the first and second electro-optical panels determines the contrast ratio of the entire electro-optical device according to the present invention.
In addition, particularly in the present invention, the first electro-optical panel emits light based on the provision of the organic EL material, and the second electro-optical panel transmits or blocks this light. That is, since the first electro-optical panel emits light by itself, it is not necessary to provide a special backlight for the second electro-optical panel including the liquid crystal (in other words, the first electro-optical panel has the second electric optical panel. It functions as a light source for the optical panel.) Therefore, in the present invention, the problem derived from the backlight itself as described above cannot occur. For these reasons, the various effects according to the present invention described above are more effectively achieved.

In the electro-optical device according to the aspect of the invention, the first electro-optical panel includes a light-emitting element including the organic EL material and first and second electrode layers sandwiching the organic EL substance. Arranged in a matrix, the color of the image may be expressed as a predetermined number of the light emitting elements.
According to this aspect, chromaticity adjustment can be suitably performed. For example, according to the configuration in which the “predetermined number” referred to in this embodiment is “3”, and R, G, and B color filters are provided for each of them, the light emission intensity of each light emitting element corresponding thereto adjusting (e.g., adjustment of 256) through, it is possible to perform color adjustment of a predetermined number of stages (e.g., 256 ³ stages of color adjustment).

Some organic EL materials emit light of a predetermined color, such as those that emit red light, those that emit green light, and those that emit blue light when energized. According to the use of a light-emitting element including such an organic EL material, the color filter may not necessarily be required for color expression by “one set” of the light-emitting element (although such light emission of each color is performed). A combination mode of a light emitting element and a color filter is also conceivable.) The present invention naturally includes the above-described embodiments within the scope thereof.
Further, in this embodiment, “one set” of “predetermined number” does not necessarily correspond to three of R, G, and B. It goes without saying that other colors and colors appropriately selected from RGB may correspond to “one set”.

In this aspect, the second electro-optical panel includes a liquid crystal element including the liquid crystal and third and fourth electrode layers sandwiching the liquid crystal, and the liquid crystal element is arranged in a matrix in a plan view, In addition, the light emitting elements may be arranged one by one corresponding to the one set of the light emitting elements.
According to this aspect, one of the liquid crystal elements has a corresponding relationship with the one set of light emitting elements that is a basis for color expression. Thereby, for example, when “light pink” is expressed by one set of light emitting elements, the luminance is adjusted with respect to the entire “light pink”.
In this sense, this aspect provides one preferred specific example relating to the hue and brightness adjustment aspect.
In addition, according to this aspect, the number of liquid crystal elements constituting the second electro-optical panel does not increase relative to the number of light emitting elements, and accordingly, a control circuit for driving the liquid crystal elements. Advantages such as simplification of the configuration can be obtained.

In this aspect, the second electro-optical panel includes a liquid crystal element including the liquid crystal and third and fourth electrode layers sandwiching the liquid crystal, and the liquid crystal element is arranged in a matrix in a plan view, In addition, the light emitting elements may be arranged one by one corresponding to one of the light emitting elements.
According to this aspect, one of the liquid crystal elements has a corresponding relationship with one of the light emitting elements. Thereby, for example, even when “light pink” is expressed by one set of light emitting elements, the luminance is one by one of the “predetermined number” of light emitting elements constituting the “light pink”. Can be adjusted.
In this sense, the present aspect provides one preferred specific example regarding the expression aspect of hue and luminance.
In addition, according to this aspect, it is clear that finer adjustments regarding color and luminance can be made. Therefore, the electro-optical device according to this aspect has a very high expression capability (or thorough the display image). Reproducibility).

In the electro-optical device according to the aspect of the invention, the luminance information may include information that causes the second electro-optical panel to block all of the light every predetermined period.
According to this aspect, if one unit / one unit of a display image is viewed side by side in time series, a “black image” is sandwiched in the image sequence every predetermined period. Become. Thereby, when the display image is, for example, a moving image, it is possible to suppress the occurrence of so-called motion blur.
Moreover, this aspect is extremely advantageous in that the effect of preventing such motion blur occurrence can be enjoyed only by relying on a simpler method of changing / adjusting the content of luminance information.

Moreover, in order to solve the above-described problems, an electronic apparatus according to the present invention includes the various electro-optical devices described above.
According to the present invention, since the above-described various electro-optical devices are provided, the color and brightness are adjusted through the first and second electro-optical panels, respectively, so that a higher quality image is obtained. Can be displayed.

  Hereinafter, an embodiment according to the present invention will be described with reference to FIGS. 1 to 3. In addition to FIGS. 1 to 3 referred to here, in each drawing referred to below, the ratio of dimensions of each part may be appropriately different from the actual one.

  As shown in FIG. 1, the electro-optical device 1 includes an organic EL panel 10 and a liquid crystal panel 20. The electro-optical device 1 can display one image by using both the panels (10, 20). In this case, the organic EL panel 10 performs color adjustment of the image in this embodiment. The liquid crystal panel 20 is used for color modulation, and the liquid crystal panel 20 is used for luminance adjustment or luminance modulation of the image. Such an action-related explanation will be touched on later.

Among the above, the organic EL panel 10 includes the element substrate 11, the sealing substrate 12, and various elements formed on the element substrate 11. The various elements herein include an organic EL element Ed, a switching element, a thin film transistor (TFT) (not shown) that functions as a current supply source to the organic EL element Ed, and the like.
The element substrate 11 and the sealing substrate 12 are made of a light-transmitting material such as glass, quartz, or plastic. In addition, the element substrate 11 and the sealing substrate 12 are bonded to each other at a peripheral portion thereof with an adhesive (see reference numeral 1JB in FIG. 2) not shown in FIG.

  The organic EL element (light emitting element) Ed has a laminated structure as shown in the upper part of FIG. This stacked structure includes a pixel electrode 113, a light emitting functional layer 18, and a counter electrode 15.

As shown in FIG. 2 or FIG. 1, the pixel electrodes 113 are formed on the element substrate 11 (“lower” in the drawing) and arranged in a matrix. The fact that the organic EL elements Ed are arranged in a matrix corresponds to the fact that the pixel electrodes 113 are arranged in a matrix as described above (see FIG. 1). A partition 340 is formed between the pixel electrodes 113 to define each pixel region. The partition 340 is made of, for example, an insulating transparent resin material (fluorine resin, acrylic resin, epoxy resin, polyimide, or the like).
The pixel electrode 113 can apply, for example, a current supplied via the TFT or the like to the light emitting functional layer 18.
Such a pixel electrode 113 is made of a translucent and conductive material such as ITO (Indium Tin Oxide).

As shown in FIG. 2, the light emitting functional layer 18 is formed on the pixel electrode 113 (“down” in terms of the drawing). The light emitting functional layer 18 includes at least an organic light emitting layer, and the organic light emitting layer is composed of an organic EL material that emits light based on a recombination phenomenon of holes and electrons. When the organic EL material is, for example, a polymer material, the organic EL material is supplied only into each space partitioned by the partition wall 340 by, for example, a droplet coating method (inkjet method).
As described above, according to the aspect in which the organic EL material is supplied only to the space partitioned by the partition wall 340, the light emitting functional layer 18 can be provided separately for each color as shown in FIG. FIG. 2 shows an example in which the light emitting functional layers 18R, 18G, and 18B including organic EL materials dedicated for red light, green light, and blue light are formed in this order along the X direction in the drawing. . Along the Y direction in the figure, there are arranged a row in which only the light emitting functional layers 18R are arranged, a row in which only the light emitting functional layers 18G are arranged, and a row in which only the light emitting functional layers 18B are arranged. The organic EL element Ed is composed of an organic EL element EdR that emits red light, an organic EL element EdG that emits green light, and an organic EL element EdB that emits blue light according to the distinction between the light emitting functional layers 18R, 18G, and 18B (FIG. In the present embodiment, the symbol “Ed” is used as a symbol for collectively referring to these “EdR”, “EdG”, and “Edb”, and the same applies to the symbol “18”. .)
In addition, as another layer which comprises the light emission functional layer 18, you may provide a part or all of an electron block layer, a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, and a hole block layer. Good.

As shown in FIG. 4, the counter electrode 15 has a rectangular shape as if it covers the entire surface of the element substrate 11 in a plan view (so-called solid shape having no special opening or gap inside). It is formed. That is, the counter electrode 15 extends over the area of the light emitting functional layer 18 defined by the partition 340 and the partition 340 so as to be common to the plurality of pixel electrodes 113.
For example, the counter electrode 15 is electrically connected to a power line (not shown) and set to an appropriate potential (for example, ground potential).
Such a counter electrode 15 is formed, for example, on a metal thin film such as Ca or Mg formed so thin that light can be transmitted, and on the metal thin film in order to reduce the electric resistance of the metal thin film. It is made from a translucent and conductive thin film such as ITO.

  The organic EL element Ed emits light based on the structure including the pixel electrode 113, the light emitting functional layer 18, and the counter electrode 15 described above. That is, (i) holes are injected into the light emitting functional layer 18 from the pixel electrode 113 serving as an anode and electrons are injected from the counter electrode 15 serving as a cathode. (Ii) Excitons are generated by recombination of these holes and electrons. (Iii) When this exciton transitions to the ground state, energy release, that is, a light emission phenomenon occurs, and so on. At this time, a proportional relationship is generally established between the magnitude of the current flowing between the pixel electrode 113 and the counter electrode 15 and the intensity of light emitted from the organic EL element Ed.

Thus, the light emitted from the light emitting functional layer 18 can travel in any of the vertical directions in FIG. If both the element substrate 11 and the sealing substrate 12 have translucency, any of the light traveling in these directions can be used. However, in this embodiment, the light traveling upward in the drawing is wasted because of the arrangement relationship with the liquid crystal panel 20 described later.
Therefore, preferably, a reflective film made of an appropriate metal material is formed on the element substrate 11 and under the pixel electrode 113, or the pixel electrode 113 itself is made of the metal material. Is preferred. More specifically, for example, the pixel electrode 113 itself is made of a conductive material such as aluminum (Al), silver (Ag), or a laminated film of Ag and ITO. Is preferred.
If this is done, the light emitted from the light emitting functional layer 18 is reflected by the reflective film or the like and travels downward in the figure (see the arrow with the symbol LC in FIG. 2). Use efficiency increases.
The type in which the light LC travels toward the side opposite to the element substrate 11 as shown in FIG. 2 and FIG. 1 is generally called a top emission type. It is not impossible to apply to the bottom emission type in which light travels toward the element substrate 11 (in this case, the reflective film and the like are provided on the sealing substrate 12 side as viewed from the pixel electrode 113). Become.). In some cases, it is not impossible to apply the present invention to the above-described dual emission type, which is a type in which light travels in any of the vertical directions in FIG.

On the other hand, the liquid crystal panel 20 includes an element substrate 21 and a counter substrate 22 and various elements formed on the element substrate 21. The various elements mentioned here include a liquid crystal element Ld, a TFT functioning as a switching element (not shown), or a storage capacitor element (capacitor) (not shown) for suitably applying a voltage to the liquid crystal element Ld. And so on.
The element substrate 21 and the counter substrate 22 are made of a light-transmitting material such as glass, quartz, or plastic. In addition, the element substrate 21 and the counter substrate 22 are bonded to each other at the peripheral portion thereof by an adhesive not shown in FIG.

  The liquid crystal element Ld has a laminated structure as shown in the lower part of FIG. This stacked structure includes a pixel electrode 213, a liquid crystal layer LQ, and a counter electrode 25.

  As shown in FIG. 2 or FIG. 1, the pixel electrodes 213 are formed on the element substrate 21 (“lower” in the drawing) and arranged in a matrix. The fact that the liquid crystal elements Ld are arranged in a matrix corresponds to the fact that the pixel electrodes 213 are arranged in a matrix as described above (see FIG. 1). These points are the same as those of the pixel electrode 113 constituting the organic EL element Ed described above.

However, as shown in FIG. 2 or FIG. 1, the pixel electrodes 213 form a matrix-like arrangement in which one pixel electrode 113 is arranged corresponding to the three pixel electrodes 113 arranged. In other words, the total number of organic EL elements Ed (“EdR”, “EdG”, and “EdB” are counted as “one”), Xe in the X direction, and Ye in the Y direction. If there are, the liquid crystal element Ld has (Xe / 3) [pieces] in the X direction and Ye [pieces] in the Y direction.
Such a pixel electrode 213 is made of a light-transmitting and conductive material such as ITO.

  The counter electrode 25 is formed as if it covers the entire surface of the counter substrate 22 (“up” from the viewpoint in the figure). The counter electrode 25 is made of a translucent and conductive material such as ITO.

  The liquid crystal layer LQ is disposed so as to be sandwiched between the pixel electrode 213 and the counter electrode 25 described above. More precisely, the liquid crystal layer LQ is disposed so as to be sandwiched between alignment films (not shown) formed on the pixel electrode 213 and the counter electrode 25, respectively. The surface of the alignment film is subjected to an alignment process for regulating the initial alignment state of the liquid crystal molecules constituting the liquid crystal layer LQ. Such an alignment film is made of a resin material such as polyimide, for example. Note that the liquid crystal layer LQ can be configured to operate in a TN mode using a liquid crystal having positive dielectric anisotropy.

Based on the above configuration, when the potential difference between the pixel electrode 213 and the counter electrode 25 is appropriately set for each liquid crystal element Ld, the alignment state of the liquid crystal molecules in the liquid crystal layer LQ sandwiched therebetween is appropriately changed. The Thereby, the ratio (transmittance) of the amount of light transmitted to the observation side in the emitted light LC from the organic EL panel 10 is controlled for each pixel electrode 213.
Although not shown, the liquid crystal panel 20 shown in FIG. 2 is provided with two polarizing plates that sandwich the panel 20 from the upper and lower sides in the figure. This polarizing plate polarizes light emitted from the organic EL panel 10 or polarizes light transmitted through the liquid crystal panel 20. The direction of polarized light by these polarizing plates is determined depending on the direction of polarized light received by the light transmitted through the liquid crystal layer LQ.

  Next, a configuration for driving the electro-optical device 1 according to the present embodiment will be described with reference to FIG. Such a configuration includes an interface 401, a YC separation circuit 402, an EL drive circuit 101, an LQ drive circuit 201, a control circuit C, and an organic EL panel 10 and a liquid crystal panel 20 as control targets, as shown in FIG.

The interface 401 receives input video data such as an HDR (High Dynamic Range) video signal and supplies it to the YC separation circuit 402.
The YC separation circuit 402 drives and controls the organic EL panel 10 for color modulation based on a pixel value X0 (this X0 is expressed by, for example, a predetermined bit number sequence) included in the input video data. A process of calculating a control value (that is, color data) Yc and a control value (that is, brightness data) Yb for driving and controlling the liquid crystal panel 20 for luminance modulation is performed (this calculation process will be described later). Touch again.)
Thus, the former color data Yc is stored in the color frame memory in the EL drive circuit 101, and the latter luminance data Yb is stored in the luminance frame memory in the color modulation LQ drive circuit 201. (All frame memories are not shown).

The EL drive circuit 101 drives the organic EL panel 10 based on the color data Yc (see also FIG. 1). The EL drive circuit 101 includes circuits for driving the scanning lines 13 and the data lines 16 provided in the organic EL panel 10. As schematically shown in FIG. 3, the scanning lines 13 and the data lines 16 are arranged so as to correspond to the respective rows and the respective columns of the organic EL elements Ed arranged in a matrix.
Thereby, each organic EL element Ed receives the supply of the color data Yc through the data line 16 by selecting the scanning line 13 line by line, for example. Thereafter, the organic EL element Ed emits light based on the color data Yc at an appropriate timing.
At this time, in the present embodiment, three organic EL elements Ed are used as one set in order to express one color. Therefore, the calculation mode of the color data Yc from the pixel value X0 or the pixel value X0 is used. Such a viewpoint is considered as to how the configuration of itself is to be performed.

The LQ driving circuit 201 drives the liquid crystal panel 20 based on the luminance data Yb (see also FIG. 1). The LQ drive circuit 201 includes circuits for driving each of the scanning lines 23 and the data lines 26 provided in the liquid crystal panel 20. These scanning lines 23 and data lines 26 are arranged so as to correspond to the respective rows and columns of the liquid crystal elements Ld arranged in a matrix, as schematically shown in FIG.
Thereby, each liquid crystal element Ld receives the supply of the luminance data Yb through the data line 26 by being selected line by line for each scanning line 23, for example. The alignment state of the liquid crystal molecules in the liquid crystal layer LQ is changed based on the luminance data Yb, but the liquid crystal element Ld thereby adjusts the transmittance of the light from the organic EL panel 10 with respect to the liquid crystal element LQ. (See FIG. 2).

The control circuit C controls the overall operation of the electro-optical device 1 according to the present embodiment. In particular, as shown in FIG. 3, the control circuit C synchronizes the operation timings of both the EL drive circuit 101 and the LQ drive circuit 201. Make adjustments. More specifically, as described above, in the present embodiment, three liquid crystal elements Ld correspond to three organic EL elements Ed, and as an example, the latter is the former. It is necessary to drive at approximately three times the speed, and it is preferable that the driving end time of the three organic EL elements Ed and the driving end time of one liquid crystal element Ld substantially coincide with each other. , And so on. The control circuit C controls the EL drive circuit 101 and the LQ drive circuit 201, and thus the organic EL panel 10 and the liquid crystal panel 20, while taking such restrictions into consideration.
However, there are various specific control methods other than those described above. The present invention basically falls within the scope of any method.

Next, the operation (particularly an example of the operation) and effect of the electro-optical device 1 according to the present embodiment described above will be described with reference to FIGS. 4 and 5 in addition to FIGS. While explaining.
In FIG. 4, for simplicity, only four liquid crystal elements Ld corresponding to the four sets when three organic EL elements EdR, EdG, and EdB are used as one set are used. An image display example is shown (hereinafter, one set of three organic EL elements EdR, EdG, and EdB may be referred to as (one) “pixel”. One of the corresponding liquid crystal elements Ld may also be referred to as (one) “pixel”.)

First, the electro-optical device 1 according to the present embodiment has three organic EL elements EdR, EdG, and EdB based on the color data Yc calculated from the pixel value X0, as shown in the uppermost row of FIG. Express one color. That is, in FIG. 4, an image having the color C1 is represented by the pixels at the upper left corner and the lower left corner in the drawing, and an image having the color C2 is represented by the pixels at the upper right corner and the lower right corner in the drawing.
In this case, the expression of these colors C1, C2, etc. is more practically performed through adjustment of the light emission intensity of each organic EL element EdR, EdG, EdB according to the principle of additive color mixing. For example, in order to express the color C1, the light emission intensities of the organic EL elements EdR, EdG, and EdB are set to specific constants α1 [%], β1 [%], γ1 [%], and the like. , Etc. (see FIG. 4). This setting depends on how much current flows between the pixel electrode 113 and the counter electrode 15 based on the specific value of the color data Yc.
From such an integrated handling of the three organic EL elements Ed and the relationship between human visual ability and the like, the viewer has “pixel” as one unit configuration, color C1 and color C2. Can be recognized.

On the other hand, at the same time, as shown in the middle part of FIG. 4, the electro-optical device 1 has one luminance with one liquid crystal element Ld based on the luminance data Yb calculated from the same pixel value X0 as described above. Express. That is, in FIG. 4, an image having luminance Y1 is represented by the pixel at the upper left corner in the drawing, an image having luminance Y2 is represented by the upper left corner and the lower right corner in the drawing, and luminance Y3 is represented by the pixel at the lower right corner in the drawing. An image with is represented.
However, in this case, even if the luminance is expressed, the liquid crystal panel 20 itself does not have the light emission capability, and this is based on the premise that the organic EL element Ed described above emits light. The example shown in the middle of FIG. 4 expresses a so-called monotone image (or an image having only brightness) that would be displayed if the liquid crystal panel 20 was irradiated with simple white light. It has become a thing. For example, an image with luminance Y1 is an example in which the alignment state of liquid crystal molecules is adjusted so that the transmittance is 100%, and an image with luminance Y3 is adjusted to have a slightly lower transmittance. It shows the examples that were made, and so on. The adjustment of the transmittance and the change of the orientation state depend on how much potential difference is set between the pixel electrode 213 and the counter electrode 25 based on the specific value of the luminance data Yb.

As a result, the viewer visually recognizes the light transmitted through the liquid crystal element Ld out of the light emitted from the organic EL element Ed. That is, as shown symbolically by the “+” symbol in FIG. 4, the viewer visually recognizes the image shown in the lowermost part of FIG. 4, which is an image in which the uppermost part and the middle part of FIG. 4 are superimposed. become.
That is, as shown in FIG. 4, the viewer recognizes an image having the color C1 and the luminance Y1 by the pixel at the upper left corner in the drawing, and recognizes an image having the color C1 and the luminance Y2 by the pixel at the lower left corner in the drawing, The image having the color C2 and the luminance Y2 is recognized by the pixel in the upper right corner in the drawing, and the image having the color C2 and the luminance Y3 is recognized by the pixel in the lower right corner in the drawing.
In this case, even if the pixels have the same color C1 in color representation (that is, the pixels at the upper left corner and the lower left corner in the figure), if the luminance is different from Y1 and Y2, the influence on the viewer is different. become. The same applies to pixels having the same color C2 (that is, pixels at the upper right corner and the lower right corner in the figure). Contrary to the case described above, even if the liquid crystal element Ld is driven by the same luminance data Yb, if the color of the light emitted from the organic EL element Ed to the liquid crystal element Ld is different, it is still the case. The influence on the viewer is different (refer to the pixels in the lower left corner and the upper right corner in the figure).
In short, in the present embodiment, a more subtle or more delicate image representation such as an image having the same color but different brightness or brightness, or vice versa, or an image having the same brightness or brightness but different color. Is possible.

Such an image configuration can also be described using a chromaticity diagram as shown in FIG.
FIG. 5 is a so-called xy chromaticity diagram. In this figure, a region enclosed in a generally bullet-like shape represents a color range (color gamut) that can be recognized by humans. The saturation increases from the vicinity of the center of the region to the periphery. A numerical value surrounding the area represents a hue.
On the other hand, a region surrounded by a triangle in the region represents a color gamut that can be expressed in the RGB color system. Among these points, the points marked with Ct are white points. In addition, characters such as “red”, “green” and the like shown in the drawing represent general color names that a viewer will feel when recognizing the color of the place where the character is located. For example, when a viewer recognizes a color around x = 0.2 and y = 0.1, the person has a high probability of judging it as “blue”.

In FIG. 5, chromaticity or tint is expressed in a so-called pure form (in other words, without the influence of lightness) in the inside of the shell-shaped shape or in the triangle. It can be said.
This is deeply related to the image shown at the top of FIG. 4, that is, color adjustment or color modulation by the organic EL element Ed. That is, the organic EL panel 10 according to the present embodiment is considered to express colors corresponding to x and y taking a certain predetermined value on the chromaticity diagram shown in FIG. 5 (that is, emitting light). Can do it. For example, if it is assumed that the color data Yc is configured as data composed of Yc (R), Yc (G), and Yc (B) for each of the three organic EL elements EdR, EdG, and EdB, These Yc (R), Yc (G), and Yc (B) are functions of xj and yj corresponding to the color Cj to be displayed (that is, the former performs a predetermined calculation / operation on the latter). It can be guided at least by applying it).

On the other hand, the image shown in the middle of FIG. 4, that is, the luminance adjustment or luminance modulation by the liquid crystal element Ld, can be explained as follows in relation to FIG.
First, if the pixel value X0 has color information on the premise of the RGB color system, generally between the RGB color system and the xyY color system,
X = 0.607 R + 0.174 G + 0.200 B
Y = 0.299 R + 0.587 G + 0.114 B
Z = 0.000 R + 0.066 G + 1.116 B
Therefore, the brightness Y can be obtained by the second equation. The luminance data Yb described above can be obtained based on Y thus obtained (in some cases, Yb = Y may be simply set).
Here, the values of x and y (chromaticity coordinates) in FIG. 5 are converted into x = X / (X + Y + Z) and y = Y / (X + Y + Z) using the above-described X, Y, and Z, respectively. However, Y cannot be expressed on FIG. 5 (as described above, FIG. 5 displays saturation and hue, but lightness (luminance) Y displays it so to speak. Lack space for). Therefore, the above-described brightness Y or brightness data Yb can be expressed once by taking the axis (Y axis) representing the increase or decrease in brightness in the direction penetrating the paper surface in FIG. 5 (see FIG. 6; see FIG. 6). Will be touched on later.)
The relationship between the brightness Y or the luminance data Yb and FIG. 5 is described as above, for example.

Note that the calculation processing of the color data Yc and the luminance data Yb in the YC separation circuit 402 shown in FIG. 3 can be executed basically on the basis of the above description.
For example, the luminance data Yb is obtained based on the above-described conversion formula between the RGB color system and the xyY color system, and the color data Yc has a specific value x as described above. , Y, or in other words, Yc = F (x, y) (F is an appropriate operator).
Regarding the latter, the color data Yc is also a value obtained from the pixel value X0 (see FIG. 3 and its description), and when the pixel value X0 has color information based on the RGB color system, If the luminance data Yb is calculated prior to the color data Yc, the color data Yc is more precisely described because the color information is considered to have already been incorporated with information relating to brightness. It can also be said that Yc = F (x, y, Yb), Yc = F (R, G, B, Yb), or more widely, Yc = F (X0, Yb).
Although generally described above, there are various ways of thinking other than the above in obtaining the color data Yc and the luminance data Yb from the pixel value X0. The present invention basically encompasses all of them.

The electro-optical device 1 described above has the following effects.
(1) First, according to the electro-optical device 1 according to the present embodiment, the organic EL panel 10 only adjusts chromaticity or tint in a pure sense, and the liquid crystal panel 20 only adjusts luminance. Therefore, it is possible to sufficiently adjust the luminance while sufficiently reproducing the color.

This becomes clearer from the description of FIG. 6, for example.
First, FIG. 6 shows the xy chromaticity diagram of FIG. 5 in a lying state and the Y axis as the third axis is expressed on a single sheet for convenience. In FIG. Consider the case where color modulation from point to point B is performed.
At this time, for example, in the case of performing color modulation using only one electro-optical panel as in the past, the transition from the point A to the point B along the xy plane is intended. Actually, there is a possibility that the transition from the point A to the point B ′ as shown in FIG. 6 may be realized. The reason is as already described in the section of [Problems to be solved by the invention]. That is, in such a case, in principle, it is necessary to adjust both lightness and hue by adjusting only the light transmittance or the light emission intensity. Therefore, regardless of the intention to modulate only the chromaticity. There is a high possibility of causing an unintended increase or decrease in brightness (note that FIG. 6 contributes to an intuitive grasp of the situation as described here, but this figure has already been described. As such, it is just a “convenient” expression.)
However, in this embodiment, such a problem does not occur. This is because, as already described, the organic EL panel 10 is specialized in color modulation or adjustment. Therefore, the modulation from the point A to the point B is performed as if the transition between the points A and B along the paper surface is performed as shown in FIG. If it is desired to realize the transition from the point B to the point B ′ as shown in FIG. 6, it goes without saying that the liquid crystal panel 20 is in charge.)

(2) In this way, in connection with the separate adjustment of color and brightness, in the electro-optical device 1 according to this embodiment, an image to be displayed in the brightness data Yb every predetermined period. It is preferable to include data that sets all or a part of the brightness to 0. In this way, if one unit / one unit of the display image is viewed side by side in time series, a “black image” is sandwiched in the image sequence every predetermined period. become. Thereby, when the display image is, for example, a moving image, it is possible to suppress the occurrence of so-called motion blur.
In this regard, in order to eliminate the motion blur, there is a conventional technique using, for example, a method of turning off the backlight every predetermined period. However, in this embodiment, the color and brightness adjustment are independent. Therefore, it is only necessary to change or adjust the content of the luminance data Yb. That is, according to the present embodiment, there is an advantage that a much simpler method can be used to obtain the same effect.

(3) According to the electro-optical device 1 according to the present embodiment, the organic EL panel 10 that emits light is provided, and the organic EL panel 10 functions as a backlight for the liquid crystal panel 20. Therefore, the problem derived from the backlight as described in the section of [Problems to be solved by the invention] cannot occur. That is, in this embodiment, since a backlight in the meaning of so-called elementary elements is not necessary, there is no need to worry about the deviation of the wavelength component of the emitted light. As a result, the various effects described above are more effective in this embodiment. It is played.

(4) Furthermore, according to the electro-optical device 1 according to the present embodiment, color data Yc and luminance data Yb composed of different bit strings or the like can be used to express color and luminance. It is possible to finely adjust the brightness. In this regard, in the case of performing color / brightness adjustment using one electro-optical panel as described above, it is necessary to include both data for color / brightness adjustment in one bit string data. It is not suitable for simple expressions.
Alternatively, the electro-optical device 1 according to the present embodiment can increase the contrast ratio of an image. This is because, theoretically, the product of the contrast ratios of the organic EL panel 10 and the liquid crystal panel 20 determines the contrast ratio of the entire electro-optical device 1 according to the present embodiment.

(5) In addition, according to the electro-optical device 1 according to the present embodiment, a structure in which one liquid crystal element Ld corresponds to three organic EL elements Ed is employed. The number of Ld should not be relatively large (see FIG. 1 etc.). Therefore, it is possible to simplify the configuration of the control circuit for driving the liquid crystal element Ld, or to obtain the advantage that the cost can be reduced accordingly.

While the embodiments according to the present invention have been described above, the electro-optical device according to the present invention is not limited to the above-described embodiments, and various modifications can be made.
(1) In the above embodiment, a structure in which one liquid crystal element Ld corresponds to three organic EL elements Ed is adopted, but the present invention is not limited to such a form.
For example, as shown in FIG. 7, the electro-optical device 1 ′ may have a structure in which one liquid crystal element Ld ′ corresponds to one organic EL element Ed.
According to this, it is possible to perform luminance modulation corresponding to each of the organic EL elements EdR, EdG, and EdB that emit light of each color. Therefore, according to such a form, it is clear that finer adjustment regarding color and luminance is possible, and therefore the electro-optical device 1 ′ has a very high expression capability (or thorough the display image). Reproducibility).

(2) In the above-described embodiment, the organic EL panel 10 includes the light emitting functional layers 18R, 18G, and 18B including organic EL materials dedicated to red light, green light, and blue light, respectively. It is not limited to such a form.
For example, as shown in FIG. 8, the organic EL panel 10 ′ has only an organic EL element Ed ′ having a light emitting functional layer containing an organic EL substance that emits white light, but includes a color filter Cf instead. It may have a structure (note that FIG. 8 is upside down with respect to FIG. 1 etc., see the contrast of the orientation of the coordinate axes in these figures).
As shown in FIG. 8, the color filter Cf includes a red color filter CfR, a green color filter CfG, and a blue color filter CfB. Each color filter CfR, CfG, CfB has a band-like shape extending so that its long side coincides with the Y direction, as shown. Such a color filter Cf is formed, for example, on the sealing substrate 12 ("down" from the viewpoint in the figure) together with a light shielding film (not shown).

  In such a structure, as shown in FIG. 8, the light LC emitted from the organic EL element Ed ′ is colored so to speak for the first time by transmitting through the color filter CfR ′, for example.

Even in such a form, it is apparent that there is no change in the operational effects that are not essentially different from the operational effects achieved by the above-described embodiment.
In addition, in the present embodiment, when the organic EL element Ed ′ is manufactured, for example, a vapor deposition method or the like can be used, so that the manufacturing process may be shortened or simplified. That is, in the above-described embodiment, the method of applying the organic EL material by the inkjet method or the like is described for each space partitioned by the partition wall 340 (see FIG. 2), but in the form of FIG. Since it becomes possible to form a light emitting functional layer all at once, there is a possibility that the labor of such fractional manufacturing can be saved.

The specific shape, installation method, and the like of the color filter Cf are not limited to those described above. Of course, a different shape or installation method may be adopted.
In the present invention, the present invention can be applied to either the form using the color filter Cf as described above or the form including the organic EL element Ed for light emission of each color as in the above embodiment. Of course, in some cases, the present invention can also be applied to a form having both. That is, for example, the red light emitted from the organic EL element EdR for red light emission further passes through the color filter CfR for red.
According to such a form, better or finer chromaticity adjustment through appropriate selection of constituent materials of the light emitting functional layer 18R constituting the organic EL element EdR, or color adjustment of the color filter CfR, etc. Alternatively, there is a possibility that modulation can be performed.

(3) In the above-described embodiment, description has been given of performing all of the color adjustment and brightness adjustment only by adjusting the driving modes of the organic EL panel 10 and the liquid crystal panel 20, but the present invention is not limited to such a form.
For example, the color adjustment / luminance adjustment can be realized through a combination of various correction processes such as gamma correction. According to this, for example, in addition to color adjustment by the organic EL panel 10 and luminance adjustment by the liquid crystal panel 20, color adjustment and luminance adjustment by various correction processes can be performed together. Needless to say, fine and delicate color adjustment and brightness adjustment can be performed.
In the above section [Problems to be Solved by the Invention], it is mentioned that it is not always appropriate to perform the various correction processes described above, but that is not necessarily the best means. The purpose of the present invention is, and as is clear from what has just been described, the present invention does not have any intention to positively exclude such correction processing.

(4) In the above embodiment, since the liquid crystal panel 20 is used for luminance adjustment, the liquid crystal panel 20 is not particularly configured to include the color filter Cf (see FIG. 8) as described above. It is not limited to such a form. That is, regardless of whether it can be called a “color filter”, it is not impossible if the liquid crystal panel 20 is provided with some modulation element for contributing to better color adjustment / brightness adjustment.
The present invention includes such embodiments within its scope.

(5) In the above embodiment, the liquid crystal panel 20 is a transmissive type, but a reflective type may be adopted depending on the case. In this case, in order to appropriately set the optical path between the reflective liquid crystal panel and the organic EL panel 10 or finally to the viewer, an optical system composed of a plurality of lenses having a predetermined shape is appropriate. It is preferable to arrange them at various locations.

<Application>
Next, an electronic apparatus to which the organic EL device according to the present invention is applied will be described.
FIG. 9 is a perspective view illustrating a configuration of a mobile personal computer using the electro-optical device according to the above-described embodiment as an image display device. The personal computer 2000 includes an electro-optical device 100 as a display device and a main body 2010. The main body 2010 is provided with a power switch 2001 and a keyboard 2002.
FIG. 10 shows a mobile phone to which the electro-optical device according to the above embodiment is applied. A cellular phone 3000 includes a plurality of operation buttons 3001, scroll buttons 3002, and the electro-optical device 100 as a display device. By operating the scroll button 3002, the screen displayed on the electro-optical device 100 is scrolled.
FIG. 11 shows a portable information terminal (PDA: Personal Digital Assistant) to which the electro-optical device according to the embodiment is applied. The information portable terminal 4000 includes a plurality of operation buttons 4001, a power switch 4002, and the electro-optical device 100 as a display device. When the power switch 4002 is operated, various types of information such as an address book and a schedule book are displayed on the electro-optical device 100.

  As an electronic apparatus to which the electro-optical device according to the present invention is applied, in addition to those shown in FIGS. 9 to 11, a digital still camera, a television, a video camera, a car navigation device, a pager, an electronic notebook, electronic paper, a calculator, Examples include a word processor, a workstation, a videophone, a POS terminal, a video player, and a device equipped with a touch panel.

1 is an exploded perspective view showing a schematic configuration of an electro-optical device according to an embodiment of the invention. FIG. 2 is a partial cross-sectional view of the electro-optical device in FIG. 1. FIG. 2 is a block diagram illustrating a configuration for driving the electro-optical device of FIG. 1. FIG. 6 is an explanatory diagram for explaining how an image to be visually recognized is configured in the electro-optical device according to the embodiment. It is an xy chromaticity diagram. FIG. 6 is a diagram in which a lightness (Y) axis as a third axis is expressed on one sheet for convenience based on the chromaticity diagram of FIG. 5. FIG. 10 is an exploded perspective view illustrating a schematic configuration of an electro-optical device according to a modification of the embodiment of the invention. FIG. 10 is an exploded perspective view showing a schematic configuration of an organic EL panel that constitutes an electro-optical device according to a modification of the embodiment of the invention. FIG. 11 is a perspective view showing an electronic apparatus to which the electro-optical device according to the invention is applied. FIG. 14 is a perspective view showing another electronic apparatus to which the electro-optical device according to the invention is applied. FIG. 14 is a perspective view showing still another electronic apparatus to which the electro-optical device according to the invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1 '... Electro-optical apparatus, 10, 10' ... Organic EL panel, 11 ... Element board | substrate, 12 ... Sealing board | substrate, Ed (EdR, EdG, EdB), Ed '... Organic EL element, 113... Pixel electrode, 15... Counter electrode, 18 (18R, 18G, 18B)... Light emitting functional layer, Cf (CfR, CfG, CfB). 22 ... counter substrate, Ld, Ld '... liquid crystal element, 213 ... pixel electrode, 25 ... counter electrode, LQ ... liquid crystal layer, 101 ... EL drive circuit, 201 ... LQ drive circuit, 402 ... ... YC separation circuit, C ... control circuit,

Claims (6)

First and second electro-optical panels including an electro-optical material whose optical characteristics change when a predetermined potential or current is applied;
Signal separation means for calculating color information and luminance information supplied to each of the first and second electro-optical panels based on an input image signal;
An electro-optical device comprising:
The electro-optical material included in the first electro-optical panel includes an organic EL (electro luminescent) material, and the electro-optical material included in the second electro-optical panel includes liquid crystal,
The first electro-optical panel includes:
Based on the color information, adjust the color of the image to be displayed,
The second electro-optical panel is
Adjusting the luminance of the image based on the luminance information while transmitting or blocking all or part of the light emitted from the first electro-optical panel;
An electro-optical device. The first electro-optical panel includes:
Including the organic EL material, and a light emitting element composed of first and second electrode layers sandwiching the organic EL material,
The light emitting elements are arranged in a matrix in plan view,
The color of the image is expressed as a set of a predetermined number of the light emitting elements.
The electro-optical device according to claim 1. The second electro-optical panel is
Including the liquid crystal, and a liquid crystal element composed of third and fourth electrode layers sandwiching the liquid crystal,
The liquid crystal element is
Arranged in a matrix in plan view, and
One by one corresponding to the one set of the light emitting elements,
The electro-optical device according to claim 2. The second electro-optical panel is
Including the liquid crystal, and a liquid crystal element composed of third and fourth electrode layers sandwiching the liquid crystal,
The liquid crystal element is
Arranged in a matrix in plan view, and
One by one corresponding to one of the light emitting elements,
The electro-optical device according to claim 2. The luminance information is
The second electro-optical panel includes information that blocks all of the light every predetermined period.
The electro-optical device according to claim 1, wherein The electro-optical device according to claim 1 is provided.
An electronic device characterized by that.

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