1. Field of Invention
The present invention relates to a driving circuit of a liquid-crystal panel, which is suitably used for displaying various kinds of information, a liquid-crystal panel, and an electronic device.
2. Description of Related Art
In so-called two-terminal device active matrix or TFD (Thin Film Diode) liquid-crystal panels, scanning electrodes are formed on one of two opposing substrates, and signal electrodes are formed on the other substrate, with a liquid-crystal layer being sealed in between the two substrates. Then, a device whose current-voltage characteristics is non-linear is interposed between the liquid-crystal layer and the scanning electrodes or between the liquid-crystal layer and the signal electrodes. An example of using a ceramic varistor as the non-linear two-terminal device can be seen in D. E. Casfleberry, IEEE, ED-26, 1979, P1123 to 1128, an example of using an amorphous silicon PN diode as the non-linear two-terminal device can be found in Togashi et al., Institute of Television Engineers of Japan (ITEJ) Technical Report ED782, IPD86-3, 1984, an example of using an MIM (Metal Insulator Metal) device as the non-linear two-terminal device can be found in D. R. Baraff et al., IEEE, ED-28, 1981, P736 to 739 and K. NiWa et al., SID84, DIGEST, 1984, P304 to 307, and other examples are known. Furthermore, technology for displaying half-tone by using a two-terminal device active matrix has been proposed, for example, in Japanese Patent No. 2576951.
In a TFD liquid-crystal panel, from a structural point of view, while one line (scanning line) of the display screen is being displayed, when the levels of the pixels contained in the one line are concentrated on a specific gradation, the electrical potentials of the signal-electrode lines change simultaneously. This change in the electrical potential is propagated to each pixel through scanning lines, causing horizontal crosstalk (hereinafter referred to simply as “crosstalk”) to occur. Crosstalk refers to that, as described above, display levels differ on the display image in the lines where the pixel levels are concentrated on a specific gradation and in the lines where the pixel levels are not concentrated on a specific gradation regardless of the fact that the same gradation is being displayed.
An aspect of the invention has been made in view of the above points. An object of the invention is to remove crosstalk, such as that described above by controlling the gradation of a display image.
In one aspect of the invention, the image display apparatus can include a display section, and a display control device for displaying, on the display section, a plurality of input pixels which form input image data in such a manner that a plurality of display pixels having gradation values differing from the gradation values of the input pixels are combined.
The image display apparatus displays input image data formed of a plurality of input pixels on a display section. Here, the input pixels refer to pixels which form the input image data. At that time, the input pixel is displayed, on the display section, as a combination of display pixels having gradation values differing from the gradation value of the input pixel. The display pixels refer to pixels displayed on the display section. For example, when there is a pixel having a particular gradation value “a” as an input pixel, the pixel is not displayed on the display section as it is kept at the pixel value “a”, but instead, a plurality of display pixels having gradation values “b”, “c”, etc., differing from the gradation value “a” are combined and displayed on the display section.
In this method, for example, even when pixels having the same gradation value “a” exist continuously in the input image data, the pixels of the same gradation value “a” are not continuously displayed, but instead, the display pixels of gradation values “b” and “c” can be displayed. Consequently, since the same gradation values are not continuously displayed, the occurrence of crosstalk resulting therefrom is reduced. At the same time, the advantage of the improved viewing angle can be obtained.
In one form of the image display apparatus, the plurality of display pixels can contain a first display pixel having a gradation value greater than the gradation value of the input pixel and a second display pixel having a gradation value less than the gradation value of the input pixel. In this form, by displaying a combination of display pixels having gradation values greater than and less than the gradation value of the input pixel, a display close to the gradation values of the input pixel becomes possible.
In one form of the image display apparatus, the plurality of display pixels are displayed so as to be adjacent to the direction of the scanning lines of the display section. As a result, since it is possible to prevent pixels of the same gradation values from continuing in the direction of the scanning lines of the display section, horizontal crosstalk in the TFD liquid-crystal panel can be effectively suppressed.
In one form of the image display apparatus, the display control device can also include a driving device for driving a pixel area of the display section on the basis of a driving pulse signal specified by the number of gradation control pulses corresponding to the gradation values of the display pixels, and a device for displaying the plurality of display pixels by controlling the gradation control pulses. In this form, by controlling the gradation control pulses, a display of display pixels of different gradation values is performed.
In one form of the image display apparatus, the input image data is moving-image data formed of a plurality of frame images, and the display control device can also include switching control device for switching and displaying, for each of the frame images, the first combination of the plurality of display pixels and the second combination of the plurality of display pixels, which differ from each other.
As described above, crosstalk can be reduced by displaying one input pixel as a plurality of display pixels, but the resolution of the image data is decreased. However, in the case of a moving image, if two types of different combinations are provided as combinations of a plurality of display pixels, and if a display is performed by switching the two combinations for each frame image, a decrease in resolution can be reduced from the viewpoint of human vision.
In one form of the image display apparatus, the display control device can include a driving device for driving a pixel area of the display section on the basis of a driving pulse signal specified by the number of gradation control pulses corresponding to the gradation values of the display pixels, and the switching control device displays a first combination of the plurality of display pixels and a second combination of the plurality of display pixels by controlling the gradation control pulses. In this form, the process for switching the combinations of the plurality of display images for each frame image can be performed by controlling the gradation control pulses. Therefore, by only inputting input image data to the display control device, a switched display is realized by a hardware process using driving means, and the like.
In one form of the image display apparatus, the switching control device can include a device for generating a first combination of the plurality of display pixels and a second combination of the plurality of display pixels on the basis of the input image data. In this form, images corresponding to a first combination and a second combination of a plurality of display pixels are generated in advance on the basis of the input image data, and by alternately displaying these images for each frame image, a switched display for each frame image is realized. Therefore, since an image to be switched and displayed is generated in advance by performing a software process on the input image data, in a display process on the display section, switching control can be realized by only alternately displaying these images.
In one form of the image display apparatus, the first combination of the plurality of display pixels is formed in such a manner that display pixels whose gradation values are greater than those of the input pixels and display pixels whose gradation values are less than those of the input pixels are alternately arranged in the direction of the scanning lines of the display section, and the second combination of the plurality of display pixels is formed in such a manner that display pixels whose gradation values are greater than those of the input pixels and display pixels whose gradation values are less than those of the input pixels are alternately arranged in sequences reverse to the first combination of the plurality of display pixels in the direction of the scanning lines of the display section. As described above, since two types of images, in which there is a difference in gradation values, that is, the light and dark patterns are reverse, can be switched and displayed for each frame, the resolution is improved.
In one form of the image display apparatus, the first combination of the plurality of display pixels and the second combination of the plurality of display pixels are formed in such a manner that subpixels whose gradation values are greater than a predetermined value and subpixels whose gradation values are less than the predetermined value are alternately arranged in units of subpixels which form each of the display pixels in the direction of the scanning lines of the display section. In this form, by causing the gradation values to differ in units of subpixels which form the display pixels, the advantage of the improved viewing angle can be improved.
In one form of the image display apparatus, the input image data is moving-image data formed of a plurality of frame images, and the display control device can include a switching control device for switching and displaying, for each of the frame images, one of the combinations of an odd number of different types of the plurality of display pixels. As described above, crosstalk can be reduced by displaying one input pixel as a combination of a plurality of display pixels, but the resolution of the image data is decreased. However, in the case of a moving image, if a plurality of types of different combinations are provided as combinations of a plurality of display pixels, and if the two combinations are switched and displayed for each frame image, a decrease in resolution can be reduced from the viewpoint of human vision. Here, by making the different combinations of display images to be switched and displayed to be an odd number of types, it is possible to prevent a voltage to be applied to the display pixels from containing DC components. A preferred example of the number of combinations of the display images is three types.
In one form of the image display apparatus, the display control device can include a driving device for driving a pixel area of the display section on the basis of a driving pulse signal specified by the number of gradation control pulses corresponding to the gradation values of the display pixels, and the switching control device can display the combination of the plurality of display pixels by controlling the gradation control pulses.
In this form, a process for switching and displaying the combinations of the plurality of display images for each frame image can be performed by controlling the gradation control pulses. Therefore, by only inputting input image data to the display control device, a switched display is realized by a hardware process using a driving device, etc.
In another aspect of the invention, the image display method for use in an image display apparatus having a display section includes an input step of inputting input image data formed of a plurality of input pixels; and a display step of displaying the plurality of input pixels on the display section in such a manner that a plurality of display pixels having gradation values differing from the gradation values of the input pixels are combined. According to this image display method, similarly to the image display apparatus, crosstalk can be reduced.
The invention will be described with reference to the accompanying drawings, wherein like numerals reference like elements, and wherein:
Preferred embodiments of the invention will now be described below with reference to the drawings.
b) shows the relationship between the scanning electrode 12 and the signal electrode 14.
The liquid-crystal panel 101 can include a plurality of scanning electrodes 12, which are provided so as to extend in the row direction, and a plurality of signal electrodes 14, which are provided so as to extend in the column direction. In each of the intersections of the electrodes 12 and 14, the non-linear two-terminal device 20 and the liquid-crystal layer 18 are connected in series, thereby forming a pixel in each intersection. The above components constitute the liquid-crystal panel 101. The non-linear two-terminal device 20 has, for example, current-voltage characteristics shown in
The scanning-signal driving circuit 100 applies a scanning potential VA to the scanning electrode 12, and the data-signal driving circuit 110 applies a signal potential VB to the signal electrode 14. The scanning potentials VA and VB will be described with reference to
On the other hand, as shown in
In other words, the waveform within each line-selection period T of the signal potential VB is set according to the gradation of each pixel in a column corresponding to the signal electrode 14 of concern. First, the signal potential VB is divided into an ON period and an OFF period for each line-selection period T. In the ON period, the waveform is set to an ON potential Von, and in the OFF period, the waveform is set to an OFF potential Voff. That is, the signal potential VB is pulse width modulated according to the gradation value. Then, the higher (the darker in the normally white mode) the gradation to be given to the pixel, the larger the ratio at which the ON period is occupied is set.
Then, the inter-electrode voltage VAB between the scanning electrode 12 and the signal electrode 14 is indicated by the solid line in
An example of the signal potential VB in this embodiment is shown in
The conversion circuit 70 converts color image signals R, G, and B, which are input externally, into data signals DR, DG, and DB. More specifically, when the color image signals R, G, and B are supplied, the conversion circuit 70 stores them in a line buffer (not shown), converts the color image signals R, G, and B into data signals DR, DG, and DB, and supplies them to the data-signal driving circuit 110. Here, the gradation value of each color of the color image signals R, G, and B is a value in the range of “0” to “15”, and these values are converted into gradation values within the line-selection period T in accordance with the table of
Furthermore, the conversion circuit 70 supplies a clock signal GCP (Gray Control Pulse) to the data-signal driving circuit 110. A method of generating the clock signal GCP will now be described. In the conversion circuit 70, a basic clock signal for dividing by 256 each line-selection period T is generated. Next, the basic clock signal is counted by an 8-bit (a maximum 255) counter, and when the count result reaches a predetermined value, one pulse of the clock signal GCP is output. This predetermined value corresponds to the gradation values (0, 13, 26, . . . 255) shown in
In
The configuration of the data-signal driving circuit 110 will now be described in detail with reference to
A register 114 latches the data signals DR, DG, and DB in units of three pixels in synchronization with the rise of each of the output signals S1 to Sm of the shift register 112. A latch circuit 116 simultaneously latches the data signals stored in the register 114 in synchronization with the rise of a latch pulse LP. A waveform conversion section 118 converts the latched data signal into the signal potential VB shown in
Next, an example of the configuration of the waveform conversion section 118 is shown in
A scanning-line driving waveform 31 is a pulse waveform applied to the scanning electrode 12, and specifies the operation potential VA. Furthermore, a signal-line driving waveform 32 is a pulse waveform applied to the signal electrode 14, and specifies the signal potential VB. As is understood from
As is understood from the waveform in the upper portion of
Next, crosstalk will now be described with reference to
More specifically, the equivalent circuit of the line X is shown in the upper portion of
On the other hand, with regard to the line Y, a driving waveform B in the lower left is applied in the area B, and a driving waveform C in the lower right is applied in the area C. Therefore, when compared to the case of the line X, the applied voltage is small in the area B where a white display is performed. As a result, the level of a spike waveform 37 which occurs in the driving waveform C becomes smaller than that of a spike waveform 36 of a driving waveform A. Therefore, a spike waveform 39 in the combined voltage waveform BC of the line Y is larger than the spike waveform 38 in the combined voltage waveform A of the line X. As a result, in the area C, the liquid-crystal layer voltage level applied to the liquid-crystal layer 18 is higher than that in the area A, and the display image becomes gray closer to black. That is, the gradations of the area C and the area A where the same gray level was tried to be displayed become different. The foregoing is the principles in which crosstalk occurs.
A description will now be given of a method of reducing crosstalk. As described above, crosstalk is likely to occur because a spike waveform becomes large as a result of the gradation of the pixels of a particular line being concentrated on one gradation. In the above-described example of the lines X and Y, since the same gray gradation is concentrated in the area A, a gray gradation, which is darker than the original gradation level is displayed. In comparison to this, in the area B, since the gradation is concentrated at the white level, this causes the signal-line voltage of the line of concern to be distributed to a waveform change of the white level and a waveform change for displaying the same gray as that of the area A. For this reason, in the area C, since the change in the electrical potential due to the spike waveform is reduced, a gray display, which is darker than that of the area A, is performed, and crosstalk has occurred. Therefore, basically, by performing gradation control so that the gradation level of the pixels in a particular line are not concentrated on one gradation, crosstalk can be reduced.
For the driving waveform, as shown in
In this case, it is preferable that, for example, the gradation value of the pixel 42a be determined to be less than the gradation value of the pixel 42 and the gradation value of the pixel 42b be determined to be greater than the gradation value of the pixel 42. As a result of the above, the combination of the pixels 42a and 42b, shown in
(the gradation value of the pixel 42)={(the gradation value of the pixel 42a)+(the gradation value of the pixel 42b)}/2.
The gradation value in this case indicates the gradation value in terms of the vision characteristics of a human being, and is not a gradation value in terms of the optical characteristics. This is because the vision characteristics of a human being are not linear, and usually has characteristics of γ=2.2 with respect to the optical luminance value.
As a result of displaying the original pixel by using the combination of pixels of different gradation levels in this manner, crosstalk can be reduced in terms of the vision of a human being.
Furthermore, by displaying the pixel at a particular gradation level as a combination of pixels at gradation levels higher and lower than that level in this manner, the viewing angle improvement advantage is obtained in addition to the crosstalk reduction advantage. The viewing angle improvement advantage is schematically shown in
a) shows an example of a case in which a particular gradation level is displayed by one pixel. In this case, the liquid-crystal molecules inside the liquid-crystal layer are oriented in one direction as shown in the figure. Consequently, the angle of the liquid-crystal molecules differs depending on the observer's viewing direction. In the liquid-crystal panel, since light and dark are displayed by light that is transmitted through or shielded by the liquid-crystal molecules, the pixels is seen dark when viewed from an observer 45b of
In comparison,
In this manner, by displaying a pixel of a particular gradation level as a combination of pixels of different gradation levels by using the crosstalk reduction method in accordance with the invention, in addition to the crosstalk reduction advantage, the viewing angle improvement advantage can also be obtained. The crosstalk reduction method can be applied to both cases where image data to be displayed is a still image and a moving image.
As described above, in the crosstalk reduction method in accordance with the invention, a pixel of a particular gradation level is displayed as pixels of two different gradation levels. As is understood from
On the other hand, in the gradation control for reducing crosstalk in accordance with the invention, as shown in
A description will now be given of advantages obtained by switching two different image patterns for each frame in this manner (hereinafter referred to as frame switching control). Basically, when the resolution is decreased due to gradation control for reducing crosstalk in accordance with the invention, the amount of decrease in the resolution can be compensated for by applying frame switching control. The secondary advantages involved therewith include the following items.
First, there is the advantage that variations in display resulting from variations in characteristics of the non-linear two-terminal devices shown in
Furthermore, the advantage of reducing the blur of the edge when a moving image is displayed on the liquid-crystal panel can be expected. More specifically, in a case where, for example, a moving image, which contains a rectangular window and such that the window moves within the display screen, is to be displayed on the liquid-crystal panel, the defect such that the edge of the window is displayed in such a manner as to linger as the window moves can occur. With respect to this, a report, in which making the change in the gradation of the display image sharp is effective, has been made (see, for example, Kazuo Sekiya et al., “Late-News Paper: Eye-Trace Integration Effect on The Perception of Moving Pictures and A New Possibility for Reducing Blur on Hold-Type Displays, 930 SID 02 DIGEST). It is considered that the above-described frame switching control allows equivalent improvements to be obtained.
Furthermore, the liquid-crystal panel has the properties such that the response of the change in the orientation of the liquid crystals in response to the application of a driving voltage is delayed. In order to reduce this delay, a technique of heightening the initial level of the driving voltage has been proposed (this technique is called a “Level Adaptive Overdrive”). However, instead, it is considered that, by applying the frame switching control, it is made difficult to sense the delay of the response of the liquid crystal by using the vision characteristics of a human being.
An exemplary embodiment of a configuration for realizing the above-described frame switching control will now be described.
A first embodiment is described first with reference to
In
Furthermore, the gradation control circuit 212b generates GCP2 corresponding to dark gradation characteristics and supplies it to the switch SW 214. Based on a switching signal from the correction control circuit 213a, the switch 214 supplies GCP1 to the coincidence detection circuit 216a with regard to the n-th line and supplies GCP2 to the coincidence detection circuit 216b with regard to the (n+1)th line.
The coincidence detection circuits 216a and 216b operate alternately, and supply a signal-line driving voltage to the driver circuit 215 in accordance with the input GCP1 or GCP2. In other words, all the pixels for one line are displayed in such a manner that the pixels corresponding to SEG1 to SEG3 are displayed at bright gradation characteristics corresponding to GCP1, and the pixels corresponding to SEG4 to SEG6 are displayed at dark gradation characteristics corresponding to GCP2. In this manner, as shown as an example in
In the first embodiment, a configuration for generating two GCPs can be provided inside a driver IC, and a display is performed by switching the GCPs by hardware control inside the driver IC. In comparison, in the second embodiment, based on input image data, images corresponding to two frames are provided by a software process, and a display is performed by switching these images. That is, in the first embodiment, the image data supplied to the driver IC is of one type, but in the second embodiment, two types of image data which is generated in a software manner are alternately supplied to the driver IC, and the driver IC simply displays the supplied image data.
The overall configuration of the second embodiment is shown in
In this embodiment, since two types of image data are alternately input from the CPU 220, it becomes possible for the LCD module 221 to display an image different for each frame, as shown in
A third embodiment is similar to the second embodiment in that mage data of two different patterns are generated by a software process, and is formed in such a manner that two RAMs for temporarily storing the generated images of two patterns can be provided to reduce the processing load on the CPU.
In the second embodiment, the load on the CPU increases and the power consumption also increases by an amount corresponding to that the CPU 220 transmits image data to the LCD module 221 each time for each frame. However, in the third embodiment, since two RAMs are provided, the load on the CPU is reduced correspondingly. Furthermore, since the image data of two different patterns are generated by a software process, it is possible to use an ordinary LCD module, and thus the hardware configuration can be simplified.
In a fourth embodiment, also, image data of two different patterns can be generated by a software process, and the processing is performed inside the LCD controller rather than by the CPU.
The CPU 220 supplies the input image data to the RAM 222. After the RAM 222 temporarily stores it, the RAM 222 supplies the input image data to the decoder 225 inside the LCD controller 223. Referring to the LUTs of two different gradation characteristics, based on the input image data supplied from the RAM 222, the decoder 225 generates image data of two different patterns (an image A and an image B), and supplies it to the switch 226. The control circuit 227 supplies a switching instruction signal for each frame to the switch 226, and controls the switch 226 so that the image A and the image B, which are supplied from the decoder 225, are alternately selected, and this image is supplied to the LCD module 221. Similarly to the second and third embodiments, the LCD module displays the supplied image data on the liquid-crystal panel 101.
In this embodiment, since the CPU 220 does not need to generate image data, the load on the CPU can be reduced correspondingly. Furthermore, since image data of two different patterns is generated by a software process, an ordinary LCD module can be used, and thus the hardware configuration can be simplified.
In the gradation control for reducing crosstalk, as shown as an example in
a) shows an example for four pixels in which the light and dark is controlled in units of subpixels. In
A description will now be given of a case in which the frame switching control is applied to the case in which gradation control is performed in units of subpixels. When the frame switching control is applied to gradation control in units of subpixels shown in
In the control for switching frame images described above, as shown in
a) shows an example in which a different image pattern is switched and displayed with three frames being one period. On the left side of
Based on the light and dark switching pattern example 1, the change in the light and dark of each pixel of the frame image of one period formed of three frames, is shown on the right side of
In the third frame, three pixels of one column on the right side are displayed as dark pixels, and the remaining pixels are displayed as bright pixels.
Another light and dark switching pattern example 2 is shown in
Also, in a case where frame switching control is performed by using three frames as one period in the manner described above, the above-mentioned decrease in the resolution can be reduced similarly to the case where frame switching control is performed by using two frames as one period, as shown in
a) shows an example of the light and dark of pixels when frame switching control is performed by using two frames as one period (that is, when the image patterns are alternately switched for each frame), as shown in
b) shows a combined voltage waveform applied to pixels “a” and “b” in
If it is assumed that the liquid-crystal display device is in a normally white mode, the level of the combined voltage waveform of the dark pixel is high (indicated by “D”), and the level of the combined voltage waveform of the bright pixel is low (indicated by “U”). As described above, in the liquid-crystal display device, since the polarity of the driving voltage is reversed for each frame, the combined voltage waveform applied to the pixels “a” and “b” is as shown in
As a result of the above, by performing frame switching control in which three frames are used as one period, the problem of DC components being applied to the liquid crystal and the problem of the occurrence of flicker do not occur, and thus a decrease in the resolution can be prevented.
A description will now be given of a method of determining the gradation value of each pixel in a case where frame switching control is performed by using three frames as one period. As described with reference to
In comparison, when frame switching control is performed by using three frames as one period, the pixel to be displayed is displayed two times as either a dark pixel or a bright pixel within three frames which form one period and is displayed as the other one time. In other words, of the three frames, the pixel is displayed as dark pixels two times and as a bright pixel one time, or is displayed as a dark pixel one time and as a bright pixel two times. If it is assumed that the gradation value of the pixel which should originally be displayed is denoted as x and the pixel is displayed by two dark pixels having a gradation value xd and one bright pixel having a gradation value xb, the gradation values xd and xb need to be determined so that the average of the gradation values of the total of the three pixels become close to the gradation value of the pixel which should originally be displayed. In the simplest example,
x=(2×xd+1×xb)/3.
In the case of the normally white display, since the pixel capacitance in the case of displaying a dark pixel is greater, the degree of the occurrence of noise in dark pixels becomes greater than that in bright pixels. Therefore, if the gradation values of dark pixels and bright pixels are determined so that the appearance frequency of the dark pixel is low and the appearance frequency of the bright pixel is high, the influence of noise can be reduced. Furthermore, when there is a situation in which the setting of the pulse width of the GCP corresponding to each gradation value becomes easy by setting the gradation values of the corresponding bright pixel and dark pixel to specific values in order to display the gradation of the pixel which should originally be displayed, it is preferable that each gradation value be determined in accordance with that situation.
In the above-described example, an example in which frame switching control is performed by using three frames as one period is shown. Alternatively, by performing frame switching control by using an odd number of frames, such as five frame or seven frames, similarly, the problem of the application of DC components or the problem of flicker do not occur, and thus a decrease in the resolution can be reduced. For example, when frame switching control is performed by using five frames as one period, a particular pixel is displayed as either a dark pixel or a bright pixel in three frames among the five frames and is displayed as the other in the remaining two frames, and thus the problem of flicker does not occur. In the case where five frames are used as one period, the DC components of the combined voltage waveform applied to the pixel are cancelled every ten frames.
As described above, by displaying a pixel to be displayed as a plurality of pixels having different gradation values, crosstalk can be reduced, and also the viewing angle improvement advantage can be obtained. However, in that case, the resolution is decreased by an amount corresponding to that one pixel is displayed by a combination of a plurality of pixels. On the other hand, in order to suppress a decrease in resolution, it is preferable that a frame switching process be performed, but if the frame switching process is applied, the viewing angle improvement advantage cannot be expected. That is, in a case where the technique is adopted in which, in order to reduce crosstalk, a pixel to be displayed is displayed as a plurality of pixels having different gradation values, the viewing angle improvement and the prevention of the reduction in resolution can be realized only selectively.
As a result, in, for example, electronic devices to which the image display apparatus of the invention is applied, the construction may be formed in such a way that a user can specify as to which one of the above should be taken with priority by input device, etc. For example, in an electronic device such as a mobile phone or a PDA, the construction is formed in such a way that the user can specify a wide viewing-angle priority mode or a resolution priority mode as a display mode by operating input keys, etc. Then, if the frame switching control is not applied in the case of the wide viewing-angle priority mode and if the frame switching control is applied in the case of the resolution priority mode, it becomes possible for the user to perform an appropriate image display in the mode preferred by the user according to the type of image to be displayed.
While this invention has been described in conjunction with the specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, preferred embodiments of the invention as set forth herein are intended to be illustrative, not limiting. There are changes that may be made without departing from the spirit and scope of the invention.
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