JP2007199726A - Image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image display device which can display high-resolution images by effectively improving reduction of the wobbling effects, resulting from a response characteristic of display elements. <P>SOLUTION: The image display device comprises display elements 1, having a display surface formed of a plurality of pixels arranged regularly; an image display control means 11, which makes these display elements 1 display different images in the sequential fields; and oscillation means 2, 3, 12 which make the optical axis of the light emitted from the display surface oscillate in the predetermined direction, and the oscillation means 2, 3, 12 are constituted so as to make the optical axis oscillate according to the response characteristics of the display elements 1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image display device that displays an image by shifting pixels by wobbling.

  As a conventional image display device, a vibration means for oscillating an optical axis of light emitted from a display element in a predetermined direction is arranged in an optical path between a display element having a discrete pixel arrangement and an observation position. Odd field and even field images are sequentially written and displayed on the same pixel, and the optical axis of the light from the display element is vibrated in a predetermined direction by the vibrating means in synchronism with the field. The surface is wobbled, and the images of the odd field and the even field are spatially separated so that the pixels are equivalently displayed in the black matrix portion having no pixels on the display surface, thereby improving the resolution. What was made is known (for example, refer patent document 1).

  FIG. 22 shows the configuration of such a conventional image display apparatus. This image display device includes a color liquid crystal panel (hereinafter referred to as a color LCD) 1 as a display element having a backlight 1a and a color liquid crystal display element 1b, and a polarization conversion element that constitutes vibration means sequentially arranged on the front side thereof. 2 and a birefringent plate 3. In the color LCD 1, for example, the number of scanning lines is ½ of NTSC, and as shown in a partial plan view in FIG. 23, R, G, and B pixels are arranged in a delta arrangement. In FIG. 22, the number of scanning lines is omitted in order to clarify the drawing.

  For example, a TN (twisted nematic) liquid crystal cell shutter (hereinafter abbreviated as TN shutter) may be used for the polarization conversion element 2 because it is relatively inexpensive and has established manufacturing technology. As shown in FIGS. 24A and 24B, the TN shutter 2 is configured by sandwiching a TN liquid crystal layer 7 between polarizing plates 6 each having a transparent electrode 5, and the switch 8 is connected to the pair of transparent electrodes 5. For example, by connecting to an AC power source 9 and turning on the switch 8 and applying an AC voltage to the TN liquid crystal layer 7 as shown in FIG. 24A, the incident light is polarized (indicated by an arrow). As shown in FIG. 24 (b), the switch 8 is turned off to cancel the application of the AC voltage to the TN liquid crystal layer 7, thereby rotating the polarization of the incident light by 90 °. It is designed to be transparent.

  The birefringent plate 3 is composed of anisotropic crystals such as quartz (α-SiO 2), lithium niobate (LiNbO 3), rutile (TiO 2), calcite (CaCo 3), chili nitrate (NaNo 3), and YVO 4. As shown in FIG. 5, the incident light of the first polarization is transmitted as ordinary light, and the incident light of the second polarization orthogonal to the first polarization is transmitted as extraordinary light. Here, the birefringent plate 3 has a thickness in the z-direction orthogonal to the xy coordinates on the display surface of the color LCD 1 that is the incident direction of light rays, and the birefringent plate 3 has a separation angle of ordinary light and extraordinary light as θ. The emitted ordinary light and extraordinary light are spatially separated by d × tan θ.

  Therefore, if the crystal axis 3a of the birefringent plate 3 is set in an appropriate direction and the TN shutter 2 is turned off as shown in FIG. 26, the polarized light from the color LCD 1 is rotated 90 ° by the TN shutter 2. By transmitting as the second polarized light and further transmitting the birefringent plate 3 as, for example, extraordinary light, the pixels on the display surface of the color LCD 1 are almost diagonally right upward from the original pixel position as shown in FIG. It can be observed at the position of the black matrix shifted by a half pixel pitch. Further, as shown in FIG. 28, when the TN shutter 2 is turned on, the polarized light from the color LCD 1 is transmitted as it is as the first polarized light without being rotated by the TN shutter 2, and further transmitted through the birefringent plate 3 as ordinary light. By doing so, the pixel on the display surface of the color LCD 1 can be observed at the original position shown in FIG.

  In the conventional image display device shown in FIG. 22, the characteristics of the TN shutter 2 and the birefringent plate 3 are used, and the odd number field and the even number of the input video signal are connected to the same pixel of the color LCD 1 via the image display control circuit 11. The image with the field is sequentially displayed, and the voltage to the TN shutter 2 is fixedly controlled on / off by the TN shutter driving circuit 12 constituting the vibration means at the same timing as the synchronizing signal of the field of the video signal to be displayed. In this manner, wobbling is performed to change the pixel position observed through the birefringent plate 3 in accordance with the direction of polarized light transmitted through the TN shutter 2, thereby improving the resolution. That is, in the odd field, the TN shutter 2 is turned off, and the observed pixel position is shifted from the original pixel position by an approximately half pixel pitch in the diagonally upper right direction as shown in FIG. 29 (in this case, each pixel position is changed). In the even field, the TN shutter 2 is turned on, and as shown in FIG. 30, the observed pixel position is the original pixel position (in this case, each pixel position is Re, Ge, Be). In this way, an image in which the number of pixels of the color LCD 1 is doubled can be observed.

  Note that the odd-numbered field image and the even-numbered field image displayed on the color LCD 1 have different video signal sampling timings by the time corresponding to the pixel shift amount. That is, when displaying an even field image, the sampling timing of the video signal is delayed by a time corresponding to approximately a half pixel pitch compared to displaying an odd field image. Since the color LCD 1 holds the image of the previous field until it is rewritten to the image of the next field, one electrode of the TN shutter 2 is divided into a plurality of lines, for example, about 5 lines, and the other electrode is common. One electrode is selected in accordance with the line scanning timing of the color LCD 1 to control the voltage application.

JP-A-6-324320

  However, according to various experiments and examinations by the present inventor, it has been found that there are various problems in the image display device adopting the conventional wobbling described above. For example, it has been found that the response characteristic in the optical rotation of the TN shutter 2 constituting the vibration means has temperature dependence, and particularly the response characteristic deteriorates at a low temperature, so that the resolution cannot be sufficiently improved.

  FIGS. 31A and 31B are diagrams for explaining the response characteristics of the TN shutter 2 in the optical rotation. FIG. 31A shows the transmittance of the first polarized light, and FIG. 31B shows the drive voltage. Here, a high-frequency voltage is applied as the drive voltage. The TN shutter 2 has a rise response time τON when the drive voltage is applied and a fall response time τOFF when the drive voltage is removed. Here, assuming that the maximum transmittance of the first polarized light in the TN shutter 2 is Tm and the minimum transmittance is To, the rise response time τON is the transmission of the first polarized light because the liquid crystal starts to behave from the time of applying the driving voltage. The rise delay time tdON until the rate reaches 10%, that is, {To +0.1 (Tm -To)}, and until the TN liquid crystal actually rises and the transmittance reaches 90%, that is, { It is represented by the sum of the rise time tr until reaching To +0.9 (Tm -To)}. The fall response time τOFF is the fall delay time tdOFF until the transmittance falls to 90% after the drive voltage is removed, and the TN liquid crystal actually starts to fall from there and the transmittance becomes 10%. It is expressed as the sum of the fall time td until.

  In the above response characteristics, the rise time tr depends on the drive applied voltage, and the fall time td depends on the material characteristics inherent to the liquid crystal, but these tr and td are the rise delay time tdON and the fall delay time tdOFF. It also depends on the temperature. For this reason, even if the same drive voltage is applied to the same TN shutter 2, the values of tdON, tr, tdOFF and td differ depending on the temperature. For example, assuming that a response speed of 30 ° C., tdON = 0.5 ms, tr = 1 ms, tdOFF = 5 ms, td = 5 ms, and therefore τON = 1.5 ms, τOFF = 10 ms, at 40 ° C., tdON≈0 ms, tr = 0.5ms, tdOFF = 2ms, td = 3ms, therefore τON = 0.5ms, τOFF = 5ms and response characteristics are improved. At 10 ° C, tdON = 1ms, tr = 2ms, tdOFF = 8ms, td = 7 ms, therefore, τON = 3 ms, τOFF = 15 ms, and the response characteristics deteriorate.

  In this way, particularly when the response characteristics of rising and falling deteriorate at low temperatures, the transmittance of the first polarized light in the TN shutter 2 of one pixel with respect to the driving voltage shown in FIG. As shown in (a). That is, in the even field, ideally, only the first polarized light is transmitted, and the information (video signal; Re, Ge, Be) possessed by the polarized light is transmitted only at the original pixel position (hereinafter also referred to as an even line). Although it should be displayed, since the second polarized light is transmitted during the rise response time τON, the information inherent to the second polarized light (video signal; Ro, Go, Bo) is shifted by the pixel to be displayed. Information that the first polarization has is also displayed at the position (hereinafter also referred to as an odd-numbered line), and the observed image is as shown in FIG. Similarly, since the first polarized light and the second polarized light are transmitted even during the fall response time τ OFF, information (video signals; Ro, Go, Bo) that should be originally displayed on the odd lines can be displayed on the even lines. As a result, the observed image becomes as shown in FIG.

  For this reason, particularly at low temperatures where the response characteristics deteriorate, the resolution of wobbling cannot be sufficiently improved by the afterglow of the previous field, and the temperature dependence of the response characteristics generally stands up compared to the rise response time τON. Since it appears prominently in the falling response time τOFF, there arises a problem that the contrast is lowered. In FIG. 32, DC drive voltages having different polarities are alternately applied to the TN shutter 2 in sequential even fields, but a high-frequency drive voltage may be applied during each voltage application period.

Here, the contrast is estimated with reference to the enlarged views of FIGS. 32 (a) and (b) shown in FIGS. 34 (a) and 34 (b). In FIG. 34 (a), the response characteristic of optical rotation is approximated by a straight line in order to simplify the calculation. Contrast Cont. Is represented by Se as the area in the even field of the transmittance of the first polarization shown in FIG. 34 (a), and So as the area in the odd field.
Cont. = (Se−So) / (Se + So) (1)
It is represented by If one field time is tF, the areas Se and So can be expressed by the following equations, respectively.
Se = tF-τON + (1/2) tr (2)
So = tdOFF + (1/2) td (3)
Therefore, the contrast Cont.
Cont. = {TF−τON−tdOFF + (1/2) (tr−td)}
/ {TF-τON + tdOFF + (1/2) (tr + td)} (4)
It becomes.

When the above-mentioned values at 30 ° C., 40 ° C., and 10 ° C. are applied to the above equation (4) as tF = 16.77 ms (1/60 s),
Cont. [30 ° C] = 0.353
Cont. [40 ° C] = 0.649
Cont. [10 ° C] = 0.121
It can be seen that the lower the temperature, the lower the contrast.

  Such a problem becomes conspicuous when the temperature changes even when the image displayed on the color LCD 1 is corrected in advance in the odd-numbered field and the even-numbered field in order to compensate for the decrease in resolution due to the response characteristic of the TN shutter 2, for example. Will be revealed.

  The response characteristics of the TN shutter 2 and its temperature dependence have been described above. As shown in FIG. 22, when the color LCD 1 is used as the display element, the color LCD 1 that constitutes the color LCD 1, such as a TFT-LCD, is also the response characteristic. Have Therefore, if the TN shutter 2 is shuttered at the same timing as the image switching timing between the odd field and the even field displayed on the LCD, the TN shutter 2 has an ideal response characteristic, and the image switching timing Even if the first polarized light and the second polarized light are selectively transmitted at the same timing, the afterglow of the previous field occurs due to the response characteristics of the LCD, and the improvement in resolution due to wobbling cannot be sufficiently exhibited. This causes a problem that the contrast is lowered.

  FIGS. 35 (a) and 35 (b) are diagrams for explaining the response characteristics of a positive type crossed Nicol LCD, in which brightness white and black in one pixel of the LCD are alternately displayed for each field. The LCD shading rate and the LCD driving voltage at that time are shown. In FIG. 35 (a), the rise delay time from when the drive voltage is applied until the light shielding rate of the pixel reaches 10% is tdON ', and the rise time until the light shielding rate reaches 90% is tr', tdON '. Is the rise response time represented by the sum of t and tr ′, τON ′, the fall delay time from when the drive voltage is removed until the shading rate drops to 90%, tdOFF ′, and from there until the shading rate reaches 10% For example, in an LCD using a TN liquid crystal, tdON ′ = 2 ms, tr ′ = 10 ms, tdOFF when the falling time is td ′, and the falling response time represented by the sum of tdOFF ′ and td ′ is τOFF ′. '= 2ms, td' = 10ms, therefore τON '= 12ms, τOFF' = 12ms, and the response characteristics are not so good.

Here, as in the case of FIG. 34, the contrast Cont. 'Is obtained by assuming that one field time is tF = 16.67 ms, the area Se' in the even field, and the area So 'in the odd field.
Cont. '= 0.160
It becomes. As described above, since the response characteristics of the LCD are poor, even if the TN shutter 2 has an ideal response characteristic, if the TN shutter 2 is shuttered in synchronization with the field, the contrast deteriorates.

  On the other hand, when an LCD is used for the display element as described above, if a direct current is used as the driving voltage, deterioration due to an internal electrochemical change occurs. Therefore, in general, a high frequency voltage is applied, An AC driving method that reverses the polarity of the voltage applied for each field is adopted.

  Here, when wobbling is performed as described above, when attention is paid to one pixel, driving is performed by inverting the polarity of the voltage applied for each field. A positive (or negative) voltage is applied, and a negative (or positive) voltage is always applied in, for example, an even field displayed at the original pixel position. However, as shown in the signal waveform of FIG. 36 when attention is paid to one pixel, the center potential Vc (one-dot chain line) of the AC driving voltage in the case of AC driving and the common electrode potential Vcom (dashed line) of the LCD are: In general, it does not match, for example, Vc> Vcom. For this reason, when trying to display pixel information of the same brightness in sequential fields, the absolute values of the drive voltages actually applied to the LCD are the same even when the absolute values of the odd and even fields in the video signal are the same as Va. Assuming that Vb = (Vc−Vcom), Vo = (Va + Vb) in the odd field, Ve = (Va−Vb) in the even field, and the absolute value Vo of the drive voltage in the odd field. Is larger than the absolute value Ve of the drive voltage in the even field.

  Thus, if the drive voltage waveform does not become symmetrical between the fields due to the difference between Vc and Vcom, even if an image with the same brightness is displayed, light and dark are produced depending on the field. For example, in the case of a positive type LCD that displays black as the absolute value of the applied voltage increases, when Vo> Ve as described above, the odd field is dark and the even field is bright. As a result, there is a problem that image unevenness in which bright and dark stripes are repeated in the wobbling image occurs, and the image quality is deteriorated.

  Meanwhile, in a binocular display device such as a head-mounted image display device (hereinafter referred to as HMD), the wobbling shown in FIG. 22 is performed as the left-eye image display device and the right-eye image display device, respectively. In some cases, an image display device is used. In this case, assuming that the shift direction of pixels by wobbling in the binocular image display device is, for example, the same diagonal direction to the right, the resolution in the frequency space is as shown in FIG. That is, when wobbling is not performed, the frequency space that can be displayed on the LCD having the pixels in the delta arrangement is an area surrounded by ± Px and ± Py. Here, when the pixel pitch in the horizontal direction of the delta arrangement is ax and the pixel pitch in the vertical direction is by, Px = 1 / ax and Py = 1 / by.

  On the other hand, when a pixel shift of a half pixel pitch is performed in the same direction in the right diagonal direction by wobbling in the binocular image display device, for example, in the horizontal and vertical directions, the frequency space is ± Px ′ and The region is surrounded by ± Py ', and the region becomes larger than the case where no wobbling is performed, because the pixel pitch is halved. However, in this case, since the frequency domain is expanded only in one direction diagonally to the right, when the image displayed on the binocular image display device is fused and observed, There is a problem that it becomes impossible to observe.

  The present invention has been made by paying attention to the above-mentioned various problems of the prior art. In particular, the first object is to effectively improve the reduction of the wobbling effect due to the response characteristics of the display element, and to provide a high-resolution image. An image display device that is appropriately configured to display the image is provided.

  Furthermore, a second object of the present invention is to provide an image display device that is appropriately configured to effectively prevent the occurrence of image unevenness and display a high-resolution and high-quality image by wobbling. is there.

  Furthermore, a third object of the present invention is to provide a binocular observation display device having left and right image display devices, and display a high resolution image by wobbling on the binocular image display device to observe as a natural image. It is an object of the present invention to provide an image display device appropriately configured so as to be able to do so.

  The invention according to claim 1, which achieves the first object, includes a display element having a display surface in which a plurality of pixels are regularly arranged, and an image for causing the display element to display different images between sequential fields. In an image display device comprising: a display control means; and a vibration means for vibrating an optical axis of light emitted from the display surface in a predetermined direction in synchronization with image switching by the image display control means, the response of the display element The vibrating means is configured to vibrate the optical axis in accordance with characteristics.

  In one embodiment of the present invention, the vibration means is provided with a polarization conversion element and a drive means for driving the polarization conversion element in accordance with response characteristics of the display element.

  The invention according to claim 3 that achieves the second object displays a display element having a display surface in which a plurality of pixels are regularly arranged, and displays different images between sequential fields on the display element. In the image display device comprising: an image display control means for causing the image display control means; and a vibration means for vibrating the optical axis of the light emitted from the display surface in a predetermined direction in synchronization with the switching of the image by the image display control means. The control means is provided with polarity inversion means for inverting the polarity of the video signal applied to the display pixel of the display element every two switching operations.

  Furthermore, in the invention according to claim 4 for achieving the third object, the left and right display elements each having a display surface in which a plurality of pixels are regularly arranged, and the left and right display elements are sequentially provided. The left and right image display control means for displaying different images between the fields, and the optical axis of the light emitted from the display surface of the corresponding display element in a predetermined direction in synchronization with the image switching by the left and right image display control means In the image display apparatus having left and right vibrating means for vibrating, the left and right vibrating means are configured so that the vibration directions of the optical axes are different.

  In an embodiment of the present invention, the vibration directions of the respective optical axes by the left and right vibrating means are symmetrical.

  According to the first aspect of the present invention, the vibration means for performing the wobbling is configured to vibrate the optical axis according to the response characteristic of the display element, so that it is possible to effectively reduce the wobbling effect due to the response characteristic of the display element. It can be improved and a high resolution image can be displayed.

  Further, according to the invention of claim 3, the image display control means for displaying different images between sequential fields on the display element, the polarity of the video signal applied to the display pixel of the display element is changed every two times of switching. Since the polarity inversion means that inverts is provided, even if the center potential in polarity inversion and the common electrode potential of the display element do not match, the occurrence of image unevenness can be effectively prevented, and high resolution and high image quality can be achieved by wobbling. Images can be displayed.

  Furthermore, according to the invention of claim 4, in the binocular observation display device that performs wobbling in the left and right image display devices, the left and right vibration means for wobbling are arranged so that the vibration directions of the optical axes are different. Since it is configured, a high-resolution video by wobbling can be observed as a natural video.

  FIG. 1 shows a configuration of a reference example of an image display apparatus developed together with the present invention. In this image display apparatus, similarly to FIG. 22, a color LCD 1 as a display element having a backlight 1a and a color liquid crystal display element 1b is used, and a TN shutter 2 and a birefringent plate 3 as polarization conversion elements are provided on the front side thereof. Are arranged sequentially. In the same manner as described in the conventional example, the color LCD 1 sequentially displays the images of the odd field and the even field of the input video signal on the same pixel via the image display control circuit 11 and the video signal. In synchronization with the synchronization signal, the TN shutter drive circuit 12 controls the TN shutter 2 to be turned on / off, whereby the pixel position observed through the birefringent plate 3 is determined according to the direction of polarized light transmitted through the TN shutter 2. Try changing wobbling. Here, the TN shutter 2, the birefringent plate 3, and the TN shutter drive circuit 12 constitute a vibration means, and the image display control circuit 11 constitutes an image display control means.

  In this reference example, in order to improve the reduction of the wobbling effect due to the temperature dependence of the response characteristic of the TN shutter 2, a sheet-like heater 21 constituting a heating means is arranged around the TN shutter 2. The heater 21 is connected to the heater drive control circuit 22, thereby supplying a required current to heat the TN shutter 2. In addition, a temperature sensor 23 is disposed in the vicinity of the TN shutter 2, and the heater drive control circuit 22 is turned on / off by the heater drive control circuit 22 based on the output of the temperature sensor 23, so that the temperature of the TN shutter 2 is controlled. Is maintained at a constant temperature at which good response characteristics can be obtained, for example, 40 ° C., within a range not exceeding the allowable temperature on the high temperature side assured as a device. Here, the heater 21, the heater drive control circuit 22, and the temperature sensor 23 constitute a temperature adjusting means of the vibration means.

  In this way, if the temperature of the TN shutter 2 is maintained at a constant temperature at which good response characteristics can be obtained by the heater 21, a high-resolution image can always be obtained by wobbling without being affected by environmental temperature changes. Can be displayed. Further, in order to further compensate the response characteristics of the TN shutter 2, even when the image displayed on the color LCD 1 is corrected in advance in the odd field and the even field, it is always good without being affected by the environmental temperature change. An image having a resolution can be displayed.

  In the above reference example, the sheet-like heater 21 is arranged around the TN shutter 2 to heat the TN shutter 2. For example, the transparent electrode itself constituting the TN shutter 2 functions as a heater. It is also possible to use a Peltier element as a heater, or to newly provide a transparent heater pattern for heat generation on the glass substrate constituting the TN shutter 2. Further, instead of newly providing a heating element such as a heater, the heat of the backlight 1a constituting the color LCD 1 is guided to the TN shutter 2 through a member having good heat conductivity, or a circuit with a large amount of heat generation is connected to the TN shutter. It is also possible to heat the TN shutter 2 by arranging it in the vicinity of 2. In these cases, preferably, in order to prevent excessive heating, a cooling means such as a Peltier element is provided thermally coupled to the TN shutter 2, and the temperature of the TN shutter 2 is detected by a temperature sensor. The cooling means is controlled so as to reach a predetermined temperature.

  In the above reference example, the TN shutter 2 is heated. However, the color LCD 1 can also be heated together with the TN shutter 2. In this way, the response characteristics of the color LCD 1 can be improved, so that the overall resolution and contrast by wobbling can be further improved. That is, the overall response characteristics of the unit combining the color LCD 1 and the TN shutter 2 can be considered as a product of the response characteristics of the individual elements, and the overall response characteristics are worse than the response characteristics of the individual elements. However, if both are heated to a predetermined temperature so as to obtain good response characteristics, such a problem can be solved.

  FIG. 2 shows the configuration of the first embodiment of the present invention. In this embodiment, in order to improve the reduction of the wobbling effect due to the response characteristics of the color LCD 1, a video signal synchronization signal is supplied from the image display control circuit 11 to the TN shutter driving means 31, and based on this synchronization signal. The TN shutter driving means 31 controls the TN shutter 2 to be on / off controlled in consideration of the response characteristics of the color LCD 1 and the response characteristics of the TN shutter 2 itself, and thereby in the direction of polarized light transmitted through the TN shutter 2. Accordingly, wobbling for changing the pixel position observed through the birefringent plate 3 is performed.

Here, when the color LCD 1 is positive type and crossed Nicol, for example, when the color LCD 1 is a positive type and a crossed Nicol, in the LCD response characteristics, for example, white with a light shielding rate of 0% (applied voltage is the minimum value) to a light shielding rate of 100. % Of the arithmetic mean of the rise time until the black becomes% (applied voltage is the maximum value) and the fall time from black to white is t _A , the time from the field switching time When t _A has elapsed, the transmittance of the first polarized light through the TN shutter 2 is approximately 50%, and therefore the transmittance of the second polarized light is also approximately 50%.

That is, as shown in FIG. 3A, when the LCD shading rate response characteristic when white and black are alternately displayed for each field on one pixel of the color LCD 1, the LCD shading rate is approximately 50%. Thus, the TN shutter 2 is shuttered so that the transmittance of the first polarized light in the TN shutter 2 is also approximately 50%. In this way, the image is displayed mainly at the original pixel position in the period α (= tF) and mainly at the pixel shift position in the period β (= tF). Here, suppose that the TN shutter 2 has an ideal response characteristic, and transmits only the first polarized light during the period α and transmits only the second polarized light during the period β. The contrast is calculated with reference to the enlarged view of FIG. In this case, the area Sα of the LCD light shielding rate in the period α and the area Sβ of the LCD light shielding rate in the period β are respectively
Sα≈3 (tr ′ + td ′) / 8 + {(tF−tdON′−tr ′) + tdOFF ′} (5)
Sβ≈ (tr ′ + td ′) / 8 (6)
It becomes. Therefore, as in FIG. 35, when tdON ′ = 2 ms, tr ′ = 10 ms, tdOFF ′ = 2 ms, td ′ = 10 ms, and tF = 16.67 ms, Sα = 16.67 and Sβ = 2.5. Cont.
Cont. = (Sα−Sβ) / (Sα + Sβ) ≈0.7
It becomes.

However, in reality, the TN shutter 2 has the response characteristics as described with reference to FIG. Therefore, in this embodiment, in order to minimize the decrease in contrast due to the response characteristic of the TN shutter 2, as shown in FIG. 2, the TN shutter driving unit 31 is based on the synchronization signal from the image display control circuit 11. The field detection circuit 32 for generating the field synchronization signal, the delay signal generation circuits 33 and 34 for delaying the field synchronization signal by time τ1 and τ2, respectively, and the TN shutter drive signal based on the delayed field synchronization signal Then, a TN shutter drive signal generation circuit 35 for applying a shutter drive voltage synchronized with the TN shutter drive signal to the TN shutter 2 is provided, and the above-mentioned from the time of field switching in consideration of the response characteristics of the TN shutter 2 in the time of a lapse of t _a, the first polarization transmittance at TN shutter 2 is approximately 5 % To drive the TN shutter 2 so that.

  The operation of this embodiment will be described below with reference to FIGS. 4 (a) to 4 (g). 4A shows the response characteristic of the LCD shading rate when white and black are alternately displayed for each field on one pixel of the color LCD 1, as in FIG. 3A. (B) shows the response characteristic of the transmittance of the first polarized light of the TN shutter 2. First, the field detection circuit 32 generates a field synchronization signal as shown in FIG. 4C based on the synchronization signal from the image display control circuit 11. This field synchronization signal is supplied to the delay signal generation circuits 33 and 34, respectively, and as shown in FIGS. 4D and 4E, according to the response characteristics of the color LCD 1 and the response characteristics of the TN shutter 2 itself. Delay time τ1, τ2. The outputs of the delay signal generation circuits 33 and 34 are supplied to the TN shutter drive signal generation circuit 35. For example, the output of the delay signal generation circuit 33 is used as a set signal and the output of the delay signal generation circuit 34 is used as a reset signal. Thus, a TN shutter drive signal as shown in FIG. 4F is generated, and the shutter drive voltage shown in FIG. 4G is applied to the TN shutter 2 in synchronization with the TN shutter drive signal. FIG. 4G shows a case where DC drive voltages having different polarities are alternately applied in sequential even fields, but a high-frequency drive voltage may be applied during each voltage application period. Good.

Here, the time tb from the start of application of the shutter drive voltage to the time when the transmittance of the first polarized light becomes approximately 50%, and the duty ratio df of the shutter drive voltage are:
tb = tdON + tr / 2 (7)
df = {tF + (tdON-tdOFF) + (tr-td) / 2} / (2.tF) (8)
Set to satisfy. Therefore, the delay times τ1, τ2 in the delay signal generation circuits 33, 34 shown in FIG.
τ1 = tF-tdON- (1/2) tr + t A ··· (9)
τ2 = 2tF−tdOFF− (1/2) td + t _A (10)
Adjust to meet.

In this way, as shown in an enlarged view of the transmittance of the first polarized light in the TN shutter 2 in FIG. 5, the area Se in the even field and the area So in the odd field are respectively
Se = tF− (5/32) tr− (5/32) td (11)
So = (5/32) tr + (5/32) td (12)
Therefore, if the color LCD 1 has ideal response characteristics, the contrast Cont. By wobbling is
Cont. = {16tF-5 (tr + td)} / (16tF) (13)
It becomes. Therefore, when the values of tr and td described in FIG. 31, for example, tr = 1 ms and td = 5 ms at 30 ° C. are applied to the above equation (13) as tF = 16.67 ms (1/60 s),
Cont. = 0.8875
Therefore, the contrast can be improved by about 53% as compared with the conventional image display device shown in FIG.

As described above, the shuttering timing and the duty ratio of the TN shutter 2 are not the same timing as the field switching, but the rising response time and the falling response time of the light shielding ratio (in the case of positive type crossed Nicols) of the color LCD 1. If the transmittance of the first polarized light of the TN shutter 2 is controlled to be approximately 50% at the time t _{A which} is ½ of the arithmetic average, the contrast due to the response characteristic of the color LCD 1 and the response characteristic of the TN shutter 2 Can be minimized. Therefore, since it is possible to minimize the simultaneous display of the same video signal on the odd lines and the even lines, as shown in FIG. 6, the odd fields Ro and Go are shifted to the odd lines shifted in the odd fields. , Bo video signals, and even fields Re, Ge, Be video signals can be effectively displayed on the even lines which are the original pixel positions in the even fields, and the resolution improvement by wobbling can be sufficiently exhibited. Can do. Here, the TN shutter 2, the birefringent plate 3, and the TN shutter driving unit 31 constitute a vibrating unit. The TN shutter 2 constitutes a polarization conversion element, and the field detection circuit 32, the delay signal generation circuits 33 and 34, and the TN shutter drive signal generation circuit 35 constitute drive means.

  In FIG. 2, since one electrode of the TN shutter 2 is divided into a plurality of lines, the above-described shuttering of the TN shutter 2 is performed for each corresponding line electrode based on the line scanning timing of the color LCD 1. You can go to In this case, the shuttering by each line electrode is synchronized with the scanning of the central pixel line of the color LCD 1 corresponding to each line electrode. Therefore, the central line electrode further delays tF / 2 from the video signal switching time. By doing so, the resolution of the region corresponding to each line electrode can be maximized. Of course, even if one electrode of the TN shutter 2 is not divided in the same manner as the other electrode, it is further delayed by tF / 2 from the video signal switching time and synchronized with the scanning of the central pixel line of the color LCD 1. By performing shuttering, it is possible to obtain the best resolution at the center of the display image.

  In addition, the shuttering of the TN shutter 2 is not limited to the above-described case. For example, in the rising response and falling response of the light shielding rate of the color LCD 1, the TN shutter is at a timing at which the LCD light shielding rate is approximately 50%. The transmittance of the first polarized light at 2 can also be approximately 50%. Accordingly, in this case, the transmittance of the first polarized light at the TN shutter 2 becomes approximately 50% at a timing delayed by tdON ′ + tr ′ / 2 from the time point when the video signal is switched from the odd field to the even field. Similarly, the TN shutter 2 is shuttered so that the transmittance of the first polarized light in the TN shutter 2 is approximately 50% at a timing delayed by tdOFF ′ + td ′ / 2 from the time point when the field is switched to the odd field. Just do it.

  In this case, as shown in FIG. 3, if the color LCD 1 has a response characteristic in which the rising response time τON ′ and the falling response time τOFF ′ are equal, as in the above-described embodiment, The period α is equal to the period β, so that the display time at the original pixel position is equal to the display time at the pixel shift position. However, depending on the color LCD 1 or the brightness to be displayed, for example, as shown in FIG. 7A, the rising response time τON ′ is shorter than the falling response time τOFF ′, or conversely, FIG. As shown in a), the rising response time τON ′ may be longer than the falling response time τOFF ′. Even in such a case, when the LCD shading rate becomes approximately 50%, the TN shutter 2 is shuttered so that the transmittance of the first polarized light through the TN shutter 2 is also approximately 50%. The image can be displayed mainly at the original pixel position and mainly at the pixel shift position in the period β. Therefore, α> β in the case of FIG. 7A and α <β in the case of FIG. 8A, and the display time at the original pixel position is different from the display time at the pixel shift position. It will be.

  7A and 8A, the TN shutter 2 is shuttered so that the display time at the original pixel position is substantially equal to the display time at the pixel shift position. You can also That is, in the case of FIG. 7A, as shown in an enlarged view in FIG. 7B, the timing at which the transmittance of the first polarized light in the TN shutter 2 becomes approximately 50% (indicated by a two-dot chain line). ) Is delayed by (α−tF) / 2 from the timing (indicated by a one-dot chain line) at which the LCD shading rate becomes approximately 50% at the rise of the LCD response characteristics, and (α−tF) / at the fall of the LCD response characteristics. Advance by 2 so that α ′ = β ′ = tF. In the case of FIG. 8A, as shown in the enlarged view of FIG. 8B, the timing at which the transmittance of the first polarized light in the TN shutter 2 becomes approximately 50% (indicated by a two-dot chain line). ) Is advanced by (β−tF) / 2 from the timing (indicated by a one-dot chain line) at which the LCD shading rate becomes approximately 50% at the rise of the LCD response characteristics, and (β−tF) / at the fall of the LCD response characteristics. Delay by 2 so that α ′ = β ′ = tF. In these cases, in order to further improve the contrast, in the case of FIG. 7B, the image in the odd field has a lower luminance than the image in the even field, and FIG. In this case, the image displayed on the color LCD 1 can be corrected so that the image in the even field has lower luminance than the image in the odd field.

  Further, the shuttering of the TN shutter 2 is not limited to the above-described case. For example, when the color LCD 1 is a positive type crossed Nicol, the response characteristic of the light shielding rate is from white to a gray scale intermediate value. The transmittance of the first polarized light at the TN shutter 2 is approximately 50% at a timing half the arithmetic mean of the rise time and the fall time from black to the grayscale intermediate value. Can also be done. In FIG. 2, the delay times τ1 and τ2 in the delay signal generation circuits 33 and 34 can be arbitrarily adjusted, and the shuttering timing of the TN shutter 2 is arbitrarily set by the observer according to the image to be displayed. It can also be configured to obtain.

  Furthermore, in order to remove the influence of the temperature dependency of the response characteristics of the color LCD 1 and the TN shutter 2, the color LCD 1 and the TN shutter 2 can be configured to be maintained at a constant temperature as described in the reference example. .

  FIG. 9 shows the configuration of the second embodiment of the present invention. In this embodiment, the occurrence of image unevenness when the color LCD 1 is driven with the polarity reversed is effectively prevented, and a high-resolution and high-quality image can be displayed by wobbling. Therefore, in this embodiment, the image display control means 41 is provided with a decoder / RGB driver 42, an LCD timing generator (TG) 43 and a frame-by-frame polarity inversion circuit 44, and the decoder / RGB driver 42 synchronizes from the input video signal. The (SYNC) signal is separated and supplied to the LCD TG 43. Based on the SYNC signal, the LCD TG 43 reverses the polarity between the vertical synchronization (VD) signal shown in FIG. 10A and the odd and even lines of each field shown in FIG. An AC drive inversion timing (FRP1) signal whose polarity is inverted every time is generated and supplied to the polarity inversion circuit 44 for each frame.

  For example, as shown in FIG. 11, the frame-by-frame polarity inverting circuit 44 is provided with a divide-by-4 circuit 45, an inverter 46, and a selector 47. The divide-by-4 circuit 45 generates a VD signal as shown in FIG. Divide by 4 and supply to selector 47. Further, the selector 47 is supplied with the FRP1 signal and the signal shown in FIG. 10 (d) obtained by inverting the FRP1 signal by the inverter 46. One of the FRP1 signal and the inverted signal thereof is divided by four. Based on the output of 45, for example, when the output of the divide-by-4 circuit 45 is at the L level, the FRP1 signal is selected, and when it is at the H level, the inverted signal of the FRP1 signal is selected, as shown in FIG. Output as FRP2 signal.

  As shown in FIG. 9, this FRP2 signal is supplied to the decoder / RGB driver 42, and the video signal supplied to the color LCD 1 based on the FRP2 signal is inverted to the color LCD 1 in units of lines. Different images are sequentially displayed in the odd and even fields. Also, the SYNC signal separated by the decoder / RGB driver 42 is supplied to the TN shutter drive circuit 12, and the TN shutter 2 is controlled to be turned on / off in synchronization with the SYNC signal, whereby the polarized light transmitted through the TN shutter 2 is transmitted. Depending on the direction, wobbling is performed to change the pixel position observed through the birefringent plate 3.

  In this way, as shown in the signal waveform when focusing on one pixel in FIG. 12, the polarity of the video signal applied to each pixel is inverted between odd fields and even fields. Inverted every two switching, that is, every frame. Therefore, even if the center potential Vc (dashed line) of the AC drive voltage and the common electrode potential Vcom (dashed line) of the LCD do not coincide with each other, the generation of bright and dark stripes that cause image unevenness can be effectively prevented. A high-quality image can be displayed with a high resolution.

  In the above description, the frame-by-frame polarity inverting circuit 44 shown in FIG. 9 includes the divide-by-4 circuit 45, the inverter 46, and the selector 47 as shown in FIG. 11, but for example, as shown in FIG. Further, the output of the divide-by-4 circuit 45 is supplied to one input terminal of the exclusive OR circuit 48, and the FRP1 signal is supplied to the other input terminal of the exclusive OR circuit 48. An FRP2 signal can also be obtained.

  In addition, the polarity of the video signal is not limited to the above-described line unit, but it can be reversed every two switching operations in units of pixels, so that the occurrence of image unevenness can be prevented more effectively.

  Furthermore, the second embodiment is appropriately combined with the above-described reference example and the first embodiment to improve the reduction of the wobbling effect due to the temperature dependence of the response characteristics of the color LCD 1 and the TN shutter 2, or the color LCD 1 and The reduction of the wobbling effect due to the response characteristics of the TN shutter 2 can also be improved.

  FIG. 14 shows a third embodiment of the present invention, which shows a configuration of an example of a head-mounted image display device (hereinafter referred to as HMD). This HMD has a display device main body 51, a temporal frame 52 and a parietal frame 53, and the display device main body 51 is observed by attaching the temporal frame 52 and the temporal frame 53 to the head of the observer 54. To be held on the face of the person 54. A rear frame 56 is attached to the temporal frame 52 via a leaf spring 55, and a speaker 57 is provided on the rear frame 56 corresponding to the position of the ear of the observer 54.

  The display device main body 51 is provided with an optical system as shown in FIG. 15A or 15B corresponding to the left and right eyeballs of the observer 54. The optical system shown in FIG. 15A is a see-through type, and the display image on the image display device 61 having the color LCD, the TN shutter, and the birefringent plate as described above is transmitted through the half mirror prism 62. Reflected by the concave mirror 63 and further reflected by the half mirror prism 62 to be enlarged and guided to the corresponding eyeball, and the external image is guided to the corresponding eyeball through the liquid crystal shutter 64 and the half mirror prism 62, for example. It is. The optical system shown in FIG. 15B guides a display image on the similar image display device 61 to the corresponding eyeball through the eyepiece lens 66.

  The display device main body 51 is connected via a cable 58 to a playback device 59 having an adjusting means 60 such as a volume for adjusting the level or the like of the audio signal, and a required video signal is displayed on the left and right images from the playback device 59. The image is supplied to the apparatus, and the left and right images with different sampling timings are displayed, and the audio signal is output from the speaker 57.

  The display device main body 51 can be connected to an existing video deck or TV tuner via a cable 58 to display images, or connected to a computer or the like for computer graphics. A video, a message video from a computer, or the like can be displayed. Further, without using the cable 58, an antenna may be provided in the display device main body 51 so that an external signal is received and displayed by radio waves. Furthermore, a stereoscopic image can be observed by supplying and displaying a video signal having parallax on the left and right image display devices, for example.

  In the above-described HMD, the color LCD constituting the image display device is as small as 1.3 inches, for example, and the number of pixels is at most 300,000 pixels. Therefore, performing wobbling as described above using such a color LCD is extremely effective in achieving high resolution and high image quality in an HMD having a wide angle of view.

  In this embodiment, in such an HMD, the wobbling video displayed on the left and right image display devices can be observed as a natural video, so that the vibration direction of the optical axis by the vibration means of the left and right image display devices, that is, Change the pixel shift direction. Here, the pixel shifting directions in the left and right image display devices are preferably symmetrical, for example, in the right-eye image display device, as shown in FIG. In the left-eye image display device, as shown in FIG. 16B, the pixels are shifted diagonally upward to the left.

  Hereinafter, a configuration example of a main part of the left and right image display apparatuses for performing such pixel shifting will be described. FIGS. 17A and 17B show the first configuration example. FIG. 17A shows the configuration of the right-eye image display device 61R, and FIG. 17B shows the configuration of the left-eye image display device 61L. ing. In this example, the left and right color LCDs 1L and 1R and the left and right TN shutters 2L and 2R have the same configuration, and the left and right birefringent plates 3L and 3R have different directions of their crystal axes 3aL and 3aR, so that the right eye The image display device 61R displays the video at the original pixel position when the TN shutter 2R is on, and displays the video at the pixel shift position in the diagonally upper right direction when the TN shutter 2R is off. The image display device 61L for the left eye displays the TN The image is displayed at the original pixel position when the shutter 2L is off, and at the pixel shift position in the diagonally upper left direction when the TN shutter 2L is on.

  FIG. 18 shows a second configuration example. FIG. 18A shows the configuration of the right-eye image display device 61R, and FIG. 18B shows the configuration of the left-eye image display device 61L. Yes. In this example, in the first configuration example shown in FIG. 17, the polarization directions of the polarizing plates on the TN shutters 2L and 2R side constituting the left and right color LCDs 1L and 1R are set to the same direction with 90 ° different from each other. In the image display device 61R for the eye, the TN shutter 2R is turned off to display the image at the original pixel position, and the TN shutter 2R is turned on to display the image at the pixel shift position in the diagonally upper right direction. The image is displayed at the original pixel position when the TN shutter 2L is on, and at the pixel shift position in the diagonally upper left direction when the TN shutter 2L is off.

  FIG. 19 shows a third configuration example. FIG. 19A shows the configuration of the right-eye image display device 61R, and FIG. 19B shows the configuration of the left-eye image display device 61L. Yes. In this example, the right-eye image display device 61R is configured in the same manner as in FIG. 18A, and the left-eye image display device 61L is configured in the same manner as in FIG. In the device 61R, the TN shutter 2R is off and displayed at the original pixel position, and the TN shutter 2R is on and the image is displayed at the pixel shift position in the diagonally upper right direction. In the left-eye image display device 61L, the TN shutter 2L is displayed. The image is displayed at the original pixel position when it is off and at the pixel shift position in the diagonally upper left direction when the TN shutter 2L is on.

  FIG. 20 shows a fourth configuration example. FIG. 20A shows the configuration of the right-eye image display device 61R, and FIG. 20B shows the configuration of the left-eye image display device 61L. Yes. In this example, contrary to the third configuration example described above, the right-eye image display device 61R is configured in the same manner as in FIG. 17A, and the left-eye image display device 61L is configured as shown in FIG. In the right-eye image display device 61R, the TN shutter 2R is turned on to display the original pixel position, and the TN shutter 2R is turned off to display the video at the pixel shift position in the diagonally upper right direction. In the ophthalmic image display device 61L, the video is displayed at the original pixel position when the TN shutter 2L is on, and at the pixel shift position in the diagonally upper left direction when the TN shutter 2L is off.

  As described above, if the left and right image display devices 61L and 61R are configured so that the pixel shifting directions are symmetric, the resolution in the frequency space is ± Px when no wobbling is performed as shown in FIG. And the frequency region surrounded by ± Py can be expanded in the right and left diagonal directions to a symmetrical frequency region surrounded by ± Px ′ and ± Py ′. Accordingly, when the images displayed on the binocular image display devices 61L and 61R are fused and observed, they can be observed as natural images.

  In this embodiment, the left and right image display devices 61L and 61R are not limited to the configuration described in FIG. 22, and may be configured by appropriately combining the configurations of the reference example, the first embodiment, and the second embodiment. You can also. Further, as described above, the pixel shift directions in the left and right image display devices 61L and 61R are not limited to the upper right direction in the right eye image display device 61R and the upper left direction in the left eye image display device 61L. The right-eye image display device 61R can be set to the left diagonally upward direction, the left-eye image display device 61L can be set to the diagonally right upward direction, and one vertical direction and the other can be set to the horizontal direction.

  The present invention is not limited to the above-described embodiments, and many variations or modifications are possible. For example, it goes without saying that one field time tF is applicable to other than 1 / 60S. Further, the present invention can be effectively applied to a case where a display element is not limited to a color LCD but is a monochrome LCD or a color or monochrome display element such as a plasma display, EL, or photochromic. Further, the pixel arrangement of the display element is not limited to the delta arrangement, and other arrangements such as a stripe arrangement and a mosaic arrangement can be used, and pixel shifting by wobbling is performed so as to interpolate the black matrix according to the pixel arrangement. It can be carried out. Further, a known polarization conversion element other than the TN shutter can be used.

It is a figure which shows the reference example of this invention. It is a figure showing a 1st embodiment of this invention. It is a figure for demonstrating the response characteristic of color LCD shown in FIG. It is a figure for demonstrating operation | movement of 1st Embodiment. It is a figure for demonstrating the transmittance | permeability of the 1st polarized light with the TN shutter in 1st Embodiment. It is a figure which shows the pixel of the display surface of color LCD observed in 1st Embodiment. It is a figure for demonstrating the modification of 1st Embodiment. Similarly, it is a figure for demonstrating another modification. It is a figure which shows 2nd Embodiment of this invention. It is a signal waveform diagram for demonstrating operation | movement of 2nd Embodiment. FIG. 10 is a circuit diagram showing a configuration of an example of a frame-by-frame polarity inverting circuit shown in FIG. 9. In 2nd Embodiment, it is a figure which shows the polarity of the video signal applied to one pixel. FIG. 10 is a circuit diagram showing a configuration of another example of the frame-by-frame polarity inverting circuit shown in FIG. 9. It is a figure which shows 3rd Embodiment of this invention. In the head-mounted image display apparatus shown in FIG. 14, it is a figure which shows two examples of the optical system provided in a display apparatus main-body part corresponding to an observer's right and left eyeballs. It is a figure for demonstrating the pixel shift direction in the image display apparatus on either side in 3rd Embodiment. It is a figure which shows the 1st structural example of the principal part of the left and right image display apparatus in 3rd Embodiment. Similarly, it is a figure which shows the 2nd structural example. Similarly, it is a figure which shows the 3rd structural example. Similarly, it is a figure which shows the 4th structural example. It is a figure for demonstrating the resolution in the frequency space by 3rd Embodiment. It is a figure which shows the structure of the conventional image display apparatus. FIG. 23 is a partial plan view showing a pixel array of the color LCD shown in FIG. 22. It is a figure for demonstrating operation | movement of TN shutter shown in FIG. Similarly, it is a figure for demonstrating operation | movement of a birefringent plate. It is a figure which shows the mode of the polarization at the time of performing pixel shift in the conventional image display apparatus. It is a figure which shows the observation pixel position in the pixel shifting state shown in FIG. It is a figure which shows the mode of polarization when not performing pixel shift in the conventional image display apparatus. It is a figure which shows the observation pixel position of the odd field by the conventional image display apparatus. Similarly, it is a figure which shows the observation pixel position of an even field. It is a figure for demonstrating the response characteristic of the optical rotation of TN shutter shown in FIG. It is a figure which shows the transmittance | permeability of the 1st polarization | polarized-light in a TN shutter at the time of paying attention to one pixel by the conventional image display apparatus, and the on / off timing of a drive voltage. It is a figure for demonstrating the problem in the conventional image display apparatus. It is a figure which expands and shows FIG. It is a figure which shows the LCD response characteristic at the time of displaying alternately white and black of the brightness in one pixel of LCD for every field, and the LCD drive voltage at that time. It is a figure which shows the polarity of the video signal applied to one pixel in the conventional image display apparatus. It is a figure for demonstrating the resolution in the frequency space by the conventional image display apparatus.

Explanation of symbols

1 Color LCD
DESCRIPTION OF SYMBOLS 1a Backlight 1b Color liquid crystal display element 2 TN shutter 3 Birefringent plate 11 Image display control circuit 12 TN shutter drive circuit 21 Heater 22 Heater drive control circuit 23 Temperature sensor 31 TN shutter drive means 32 Field detection circuit 33, 34 Delay signal generation Circuit 35 TN shutter drive signal generation circuit 41 Image display control means 42 Decoder / RGB driver 43 LCD timing generator (TG)
44 Polarity inversion circuit for each frame 45 4 divider circuit 46 inverter 47 selector 48 exclusive OR circuit 51 display device main body 61L left eye image display device 61R right eye image display device

Claims (5)

A display element having a display surface in which a plurality of pixels are regularly arranged, an image display control means for displaying different images between sequential fields on the display element, and synchronization with image switching by the image display control means Then, in an image display device having vibration means for vibrating an optical axis of light emitted from the display surface in a predetermined direction,
An image display device, wherein the vibration means is configured to vibrate the optical axis in accordance with response characteristics of the display element. The image display device according to claim 1,
The vibration means includes a polarization conversion element and a drive means for driving the polarization conversion element in accordance with response characteristics of the display element. A display element having a display surface in which a plurality of pixels are regularly arranged, an image display control means for displaying different images between sequential fields on the display element, and synchronization with image switching by the image display control means Then, in an image display device having vibration means for vibrating an optical axis of light emitted from the display surface in a predetermined direction,
The image display control device comprises a polarity reversing device for reversing the polarity of a video signal applied to a display pixel of the display element every two switching operations. Left and right display elements each having a display surface in which a plurality of pixels are regularly arranged; left and right image display control means for displaying different images between sequential fields on each of the left and right display elements; In the image display device having left and right vibrating means for vibrating the optical axis of the light emitted from the display surface of the corresponding display element in a predetermined direction in synchronization with the image switching by the image display control means,
An image display device characterized in that the left and right vibration means are configured so that the vibration directions of the optical axes are different. The image display device according to claim 4.
An image display device characterized in that the vibration directions of the respective optical axes by the left and right vibrating means are symmetrical.

Images