JP2007148420A - Image display device and portable terminal device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image display device whose brightness is not lowered on reflection display and which has excellent display quality, and a portable terminal device using the same. <P>SOLUTION: In a display panel 2, a plurality of display units including a pixel for displaying an image for a left eye and a pixel for displaying an image for a right eye in one display unit are arranged in the form of a matrix. A lenticular lens 3 is arranged in front of the display panel 2, has repeated convex surfaces formed on its surface and distributes light emitted from each pixel in a horizontal direction from the pixel for displaying the image for the left eye to the pixel for displaying the image for the right eye in display unit. A reflection plate 4 reflects exterior light toward the display panel and has surface projections 41 formed on its surface. In this case, the focal distance f of the lens is different from a distance HR between the surface of the reflection plate 4 and the apex of the lens. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image display device that uses a lens such as a lenticular lens or a fly-eye lens and can display images different from each other toward a plurality of viewpoints, and a portable terminal device using the image display device. The present invention relates to an image display device having no reduction in brightness and excellent display quality, and a portable terminal device using the image display device.

  Conventionally, a display device capable of displaying a stereoscopic image has been studied. In 280 BC, Greek mathematician Euclid considers that "stereoscopicity is the sense that the left and right eyes simultaneously see different images viewed from different directions of the same object" (for example, Non-Patent Document 1: Chihiro Masuda “3D Display” Sangyo Tosho Co., Ltd.). That is, as a function of the stereoscopic image display device, it is necessary to present images with parallax to both the left and right eyes.

  As a method for concretely realizing this function, more stereoscopic image display methods have been studied than before, but these methods can be roughly divided into a method using glasses and a method using no glasses. Among these, there are anaglyph methods that use the difference in colors and polarized glasses methods that use polarized light, etc., but in recent years, the inconvenience of wearing glasses cannot be avoided. A method without glasses that does not use glasses has been actively studied.

  Examples of the method without glasses include a lenticular lens method and a parallax barrier method. The lenticular lens system is invented around 1910 by Ives et al. The parallax barrier method was conceived by Berthier in 1896 and was proven by Ives in 1903.

  The lenticular lens system was invented around 1910 by Ives et al., For example, as described in Non-Patent Document 1 described above. FIG. 22 is a perspective view showing the lenticular lens 121, and FIG. 23 is an optical model diagram showing a stereoscopic display method using the lenticular lens. As shown in FIG. 22, the lenticular lens 121 has a flat surface on one side, and a convex surface (cylindrical lens) 122 extending in one direction on the other surface, and the longitudinal directions thereof are parallel to each other. A plurality are formed so as to be.

  As shown in FIG. 23, a lenticular lens 121, a display panel 106, and a light source 108 are arranged in this order from the observer side, and the pixels of the display panel 106 are located on the focal plane of the lenticular lens 121. In the display panel 106, pixels 123 that display an image for the right eye 141 and pixels 124 that display an image for the left eye 142 are alternately arranged. At this time, a group of pixels 123 and 124 adjacent to each other corresponds to each convex portion 122 of the lenticular lens 121. Thereby, the light emitted from the light source 108 and transmitted through each pixel is distributed by the convex portion 122 of the lenticular lens 121 in a direction toward the left and right eyes. As a result, it is possible to cause the left and right eyes to recognize different images, and to allow the observer to recognize a stereoscopic image.

  On the other hand, the parallax barrier method was conceived by Berthier in 1896 and proved by Ives in 1903. FIG. 24 is an optical model diagram showing a stereoscopic image display method using a parallax barrier. As shown in FIG. 24, the parallax barrier 105 is a barrier (light-shielding plate) in which a number of thin vertical stripe-shaped openings, that is, slits 105a are formed. A display panel 106 is disposed in the vicinity of one surface of the parallax barrier 105. In the display panel 106, the right-eye pixels 123 and the left-eye pixels 124 are arranged in a direction orthogonal to the longitudinal direction of the slits. A light source 108 is disposed in the vicinity of the other surface of the parallax barrier 105, that is, on the opposite side of the display panel 106.

  Light that is emitted from the light source 108, passes through the opening (slit 105 a) of the parallax barrier 105, and passes through the right-eye pixel 123 becomes a light beam 181. Similarly, light emitted from the light source 108, passing through the slit 105 a, and passing through the left eye pixel 124 becomes a light beam 182. At this time, the position of the observer who can recognize the stereoscopic image is determined by the positional relationship between the parallax barrier 105 and the pixels. That is, the observer's right eye 141 is in the pass band of all the luminous fluxes 181 corresponding to the plurality of right eye pixels 123, and the observer's left eye 142 is in the pass band of all the luminous fluxes 182. Is required. This is a case where the midpoint 143 between the right eye 141 and the left eye 142 of the observer is located within the quadrangular stereoscopic visible area 107 shown in FIG. 24 in FIG. Among the line segments extending in the arrangement direction of the right-eye pixel 123 and the left-eye pixel 124 in the stereoscopic viewable area 107, the line segment that passes through the intersection 107a of the diagonal lines in the stereoscopic viewable area 107 is the longest line segment. For this reason, when the middle point 143 is located at the intersection 107a, the tolerance when the position of the observer is shifted in the left-right direction is maximized, and thus the observation position is most preferable. Therefore, in this stereoscopic image display method, the distance between the intersection 107a and the display panel 106 is set as the optimum observation distance OD, and it is recommended to the observer to observe at this distance. A virtual plane in which the distance from the display panel 106 in the stereoscopic visible range 107 is the optimum observation distance OD is referred to as an optimum observation surface 107b. As a result, light from the right eye pixel 123 and the left eye pixel 124 reaches the observer's right eye 141 and left eye 142, respectively. Therefore, the observer can recognize the image displayed on the display panel 106 as a stereoscopic image.

  When the parallax barrier method was originally devised, the parallax barrier was disposed between the pixels and the eyes, which was problematic because it was unsightly and low in visibility. However, with the recent realization of liquid crystal display devices, the parallax barrier 105 can be disposed on the back side of the display panel 106 as shown in FIG. For this reason, a parallax barrier type stereoscopic image display device has been actively studied.

  However, while the parallax barrier method is a method that “hides” unnecessary rays by the barrier, the lenticular lens method changes the light traveling direction, and in principle the brightness of the display screen is the lenticular lens method. There is an advantage that there is no decrease in For this reason, application to portable devices and the like where high brightness display and low power consumption performance are particularly important is being studied. Note that a stereoscopic image display device using a conventional lenticular lens uses a transmissive liquid crystal display device as a display panel.

  As an image display device using a lenticular lens, in addition to a stereoscopic image display device, a multiple image simultaneous display device that simultaneously displays a plurality of images has been developed (see, for example, Patent Document 1). This is a display that simultaneously displays different images for each viewing direction under the same conditions using the image distribution function of the lenticular lens. Thereby, one multiple image simultaneous display apparatus can provide mutually different images simultaneously to a plurality of observers positioned in mutually different directions with respect to the display apparatus. Patent Document 1 describes that by using this multiple image simultaneous display device, it is possible to reduce the installation space and the electricity cost as compared with the case where a normal single image display device is prepared for the number of images to be displayed simultaneously. Has been.

  Conventionally, the use of a reflection type flat image display device having a reflection plate for a display panel has been studied. In the reflective display device, light incident from the outside is reflected by a reflecting plate located inside the display device, and this reflected light is used as a display light source, so that a backlight or sidelight as a light source is not necessary. On the other hand, a transmissive display device requires a light source such as a backlight or a sidelight. Therefore, when a reflective display device is used for the display panel, lower power consumption can be achieved than when a transmissive display device is used. For this reason, in recent years, the application of reflective display devices to portable devices and the like has been promoted.

  However, when the reflective display device is used in this way, when the shape of the reflector is a flat surface, the external light is reflected like a mirror surface, so that a pattern of a light source such as a fluorescent lamp is reflected. There is a problem that the display quality deteriorates. In addition, since only the incident light from a specific angle contributes to the display for the observer, there is a problem that the utilization efficiency of external light is reduced.

  For this reason, as described in JP-A-8-184846 (Patent Document 2), a technique for providing a concavo-convex shape on a reflecting plate has been proposed. FIG. 25 shows an example of the structure of a reflector having an uneven shape. An uneven film 41 is formed on the surface of the reflector 4 by providing an organic film below the reflector 4 and forming irregularities on the surface of the organic film. Due to the uneven shape, external light incident from a specific direction is diffused and reflected in various directions. In addition, external light incident from various directions is also reflected in the observer direction. As a result, reflection of the light source pattern can be prevented, and external light having various angles can be used for display.

  As described above, the stereoscopic image display device using the lenticular lens and the reflective flat display device are known per se.

Chihiro Masuda "3D Display" Sangyo Tosho Co., Ltd. Japanese Patent Laid-Open No. 06-332354 (FIG. 9) JP-A-8-184846

  However, although a stereoscopic image display device using these lenticular lenses and a reflective flat display device both have the advantage of low power consumption, there is a conventional stereoscopic image display device that combines the two. There wasn't.

  Accordingly, the present inventors have eagerly realized a display device capable of displaying a stereoscopic image in a reflective display by combining the above-described stereoscopic image display device and a reflective flat display device, and reducing power consumption. investigated. As a result, the following new problems became clear.

  That is, there is a problem that a region where the luminance is partially reduced occurs depending on the observation position in the three-dimensional visible region of the eyelid that has a substantially uniform luminance. When the observation position is changed, the display appears dark at the position where the luminance is lowered, and a dark line pattern is observed in some cases. In addition, the unevenness of luminance deteriorates the quality of stereoscopic image display.

  Before describing this problem, first, a conventional stereoscopic image display device using a transmissive liquid crystal display panel and a lenticular lens will be described. FIG. 26 is a perspective view showing a twin-lens stereoscopic image display device. One cylindrical lens constituting the lenticular lens 3 is arranged corresponding to two pixels (the left-eye pixel 51 and the right-eye pixel 52) of the display panel 2. As shown in FIG. 27, the light from the left-eye pixel 51 or the right-eye pixel 52 of the display element is refracted by the lenticular lens 3 and emitted toward the region EL or ER, respectively. For this reason, when the observer places the left eye 61 in the region EL and the right eye 62 in the region ER, an image for the left eye is input to the left eye 61 and the right eye 62 is used for the right eye. A three-dimensional image can be recognized.

Next, the size of each part of the stereoscopic image display device using the lenticular lens will be described using the optical model shown in FIG. The interval between the center of the convex portion on the surface of the lenticular lens 3 and the display pixel is H, and the refractive index of the lenticular lens 3 is n. The center of the convex portion on the surface of the lenticular lens 3 is the apex of the lenticular lens 3. It is assumed that one side of the lenticular lens 3 is a flat surface, and a convex cylindrical lens, that is, a large number of kamaboko-shaped convex portions 31 extending in one direction are arranged on the other side. The focal length of the lenticular lens 3 is f, and the lens pitch is L. The pixels of the display element 2 are each arranged with one left-eye pixel 51 and right-eye pixel 52 as a set. The pitch of each pixel is P. A pair of two pixels, one for left eye pixel 51 and one for right eye pixel 52, corresponds to one convex portion 31. Further, the distance between the lenticular lens 3 and the observer is OD, and the enlarged projection width of the pixel at this distance OD, that is, the left-eye pixel 51 and the right on the virtual plane separated from the lens by the distance OD and parallel to the lens. The width of the projected image of the eye pixel 52 is assumed to be e. Further, the distance from the center of the convex portion 31 located at the center of the lenticular lens 3 to the center of the convex portion 31 located at the end of the lenticular lens 3 is W _L, and the pixel for the left eye located at the center of the display element 2 51 and the center of the pair of right-eye pixel 52, the distance between the center of the pixel pair located at the end of the display element 2 and W _P. Furthermore, the incident angle and the outgoing angle of light at the convex portion 31 located in the center of the lenticular lens 3 are α and β, respectively, and the incident angle and outgoing angle of the light at the convex portion 31 located at the end of the lenticular lens 3 are respectively shown. Let γ and δ be. Distance W the difference between _L and the distance W _P is C, the distance W number of pixels contained in the area of _P is referred to as the 2m.

  Usually, since a lenticular lens is often designed in accordance with a display element, P is treated as a constant. Further, n is determined by selecting the material of the lenticular lens. On the other hand, the distance OD between the lens and the observer and the pixel enlarged projection width e at the observation distance OD are set to desired values. These values are used to determine the distance H and lens pitch L between the lens surface and the pixel. From Snell's law and geometrical relationships, the following formulas 1 to 6 hold. Also, the following formulas 7 to 9 are established.

  From the above formulas 2, 1 and 3, the following formulas 10, 11 and 12 are established, respectively.

  Further, the following formula 13 is established from the above formulas 6 and 9. Further, from the above formulas 7 to 9, the following formula 14 is established. Furthermore, from the above formula 5, the following formula 15 is established.

  As shown in the following formula 16, since the distance H between the center of the convex portion of the lenticular lens surface and the pixel is usually set equal to the focal length f, the curvature radius r of the lens can be obtained by the following formula 17.

  Next, based on the above design, a computer simulation of a stereoscopic image display apparatus was performed using a commercially available ray tracing simulator. FIG. 29 is a diagram showing an optical model used for this simulation. In this example, a display element having a pixel pitch P of 0.24 mm is assumed, and polymethyl methacrylate (PMMA) having a refractive index n of 1.49 is used as the material of the lenticular lens 3, and the lens and the observer are used. When the distance OD is 280 mm, the pixel expansion projection width e at the distance OD is 65 mm, and the value of m is set to 60, the distance H between the lens surface and the pixel is 1.57 mm and the focal length f of the lens according to the above formulas. Is 1.57 mm, the lens pitch L is 0.4782 mm, and the radius of curvature r of the lens is 0.5161 mm. Thereby, the light receiving surface 18 is disposed at a position of 280 mm from the lens surface. Further, since the pixel pitch P = 0.24 mm, the pixel width is 0.24 mm. And the light emission area | region 17 was arrange | positioned in the center part of the pixel. The width of the light emitting region 17 was set to 0.186 mm. Accordingly, a non-display area having a width of 0.027 mm is provided on both sides of the light emitting area 17. The light emitted from the light emitting region 17 was diffused light. The non-display area corresponds to a light-shielding portion arranged for the purpose of preventing color mixing of the display device or transmitting a display signal to the pixel. Furthermore, in order to facilitate the simulation, only one pixel for the right eye located near the center of the display element is set.

  FIG. 30 is a graph showing the results of this simulation, with the horizontal axis representing the observation position on the observation surface separated from the lens surface by the distance OD = 280 mm, and the vertical axis representing the illuminance at this observation position. The illuminance in the range from −60 mm to 0 mm at the observation position on the horizontal axis is high, and the value is substantially uniform. That is, when the right eye is placed in this range, a sufficient amount of light is incident on the right eye and almost no light is incident on the left eye. In an actual stereoscopic image display device, when a left eye image is displayed on a left eye pixel and a right eye image is displayed on a right eye pixel, the left eye image is input to the left eye. The right-eye image is input to the right eye, and separation of both images is sufficiently ensured, which means that the observer can recognize the stereoscopic image well.

  Next, in order to make the above-described stereoscopic display device a reflective display, a computer simulation was performed with the light emitting region of the pixel set to a reflector. FIG. 31 is a diagram showing an optical model used for this simulation. The concave / convex shape 41 is set only on a part of the reflecting plate 4 in order to clarify the difference from the flat portion. Specifically, three rows of protrusions with a slope angle of 30 ° and a height of 2 μm were provided at a pitch of 10 μm with respect to the center of the reflector. The light source 19 was set to a width that covers all the lenses, and was placed at a position 1 mm from the lens surface. The light from the light source 19 is diffused light. FIG. 32 is a graph showing the simulation result. It can be seen that a decrease in illuminance occurs at a position of −30 mm. That is, when observing at this position, there is a problem that the display becomes dark and observed.

  Moreover, although one pixel was taken up in the above simulation, in general, the concavo-convex shape exists at random positions over all display pixels. Then, since the brightness is observed differently for each pixel of the display device, the difference in brightness is superimposed on the stereoscopic image and observed. As a result, there is a problem that the quality of the stereoscopic image display is deteriorated. Such a problem is not limited to a stereoscopic image display device, but generally occurs in a display device that simultaneously displays different images from a plurality of viewpoints such as the above-described multiple image simultaneous display device. To do.

  The present invention has been made in view of such problems, and an object of the present invention is to provide an image display device which has excellent display quality and brightness is not lowered in reflective display, and a portable terminal using the image display device.

  In the image display device according to the first aspect of the present invention, a plurality of display units including at least a pixel for displaying an image for a first viewpoint and a pixel for displaying an image for a second viewpoint are arranged in a matrix in one display unit. A display panel, a lens formed in front of the display panel and formed with a plurality of lens elements that refract light emitted from the pixels and emit the light in different directions, and the display panel or the display A reflective plate disposed behind the panel and reflecting external light toward the lens and having a concavo-convex shape on the surface, and a focal length f of the lens is between the surface of the reflective plate and the apex of the lens It is different from the distance H between.

  In the present invention, since the light collected by the lens has a certain area on the surface of the reflecting plate, it is reflected at a plurality of types of inclination angles such as uneven slopes and flat parts, and the reflected light is Proceed to various angles. This part also proceeds in the direction of the observer, and can contribute to display. Thereby, the brightness | luminance fall resulting from uneven | corrugated shape can be prevented.

  The image display device according to the second aspect of the present invention is a pixel that includes a transmission region and a reflection region in one display unit and displays a first viewpoint image, and a pixel that includes a transmission region and a reflection region and displays a second viewpoint image. And a plurality of lens elements that are arranged in front of the display panel and refract light emitted from the pixels and emit the light in different directions. And a light source that irradiates light to the transmission area of the display panel, and a reflection area in the display panel or a rear area of the reflection area of the display panel that reflects external light toward the lens. And a reflecting plate having a concavo-convex shape on the surface, the focal length f of the lens being different from the distance H between the surface of the reflecting plate and the apex of the lens.

  Also in this image display device, the light collected by the lens has a certain area in the reflection region, and thus is reflected at a plurality of types of inclination angles such as uneven slopes and flat parts, and the reflected light is Proceed to various angles. Since this part also proceeds in the direction of the viewer, it can contribute to display, thereby preventing a decrease in luminance due to the uneven shape.

  In the image display device according to the present invention, it is preferable that a focal length of the lens is smaller than a distance between the reflecting plate and the lens.

  Furthermore, in the image display device according to the present invention, when the pitch of the lens is L and the minimum pitch of the concavo-convex shape is V, the focal length f of the lens and the surface of the reflector and the vertex of the lens It is preferable that the distance H between the two satisfies Expression 18.

  Furthermore, the image display device according to the present invention has an optimum observation distance as OD, an enlarged projection width of a pixel at the optimum observation distance OD as e, a refractive index of the lens as n, and a pixel pitch of the display element as P. In this case, it is preferable that the focal length f of the lens satisfies the following formulas 19 to 21.

  Thereby, in this invention, the luminance fall resulting from uneven | corrugated shape can be suppressed more.

  The image display device according to the present invention includes the optimum observation distance OD, the pixel enlargement projection width e, the refractive index n of the lens, the distance H between the surface of the reflector and the center of the convex portion of the lens surface, and It is preferable that the pixel pitch P of the display element satisfies the formulas 19 to 20 and the following formula 22.

  In the present invention, the present invention can be applied even when the distance between the lens surface and the pixel is fixed, and the luminance reduction due to the uneven shape can be suppressed.

  The image display device according to the present invention can be configured such that the focal length of the lens is greater than the distance H between the surface of the reflector and the apex of the lens.

  Furthermore, in the image display device according to the present invention, the focal length f of the lens, the distance H between the surface of the reflector and the apex of the lens, the lens pitch L, and the minimum pitch V of the uneven shape are as follows: It is preferable to satisfy Equation 23.

  Furthermore, in the image display device according to the present invention, the optimum observation distance OD, the pixel enlargement projection width e, the refractive index n of the lens, the focal length f of the lens, and the pixel pitch P of the display element are represented by the equations 19 to 19. 21 is preferably satisfied. In the present invention, the distance between the lens surface and the pixel can be reduced. Thereby, the total thickness of the image display device can be reduced.

  Furthermore, the image display device according to the present invention includes the optimum observation distance OD, the pixel enlargement projection width e, the refractive index n of the lens, the distance H between the surface of the reflector and the vertex of the lens, and the display. It is preferable that the pixel pitch P of the element satisfies the formulas 19 to 20 and 22. In the present invention, the focal length can be set large. Thereby, since the height of the unevenness of the lens can be reduced, the lens pattern becomes less conspicuous, and the display quality of the image is improved.

  In the image display device according to the third aspect of the present invention, a plurality of display units including at least a pixel for displaying an image for a first viewpoint and a pixel for displaying an image for a second viewpoint are arranged in a matrix in one display unit. A display panel, a lens formed in front of the display panel and formed with a plurality of lens elements that refract light emitted from the pixels and emit the light in different directions, and the display panel or the display A reflective plate disposed behind the panel and reflecting external light toward the lens and having a concavo-convex shape on the surface, and the concavo-convex shape on the surface of the reflective plate reflects the incident light multiple times. It has a shape.

  The image display device according to the fourth aspect of the present invention is a pixel that includes a transmission region and a reflection region in one display unit and displays an image for a first viewpoint, and a pixel that includes a transmission region and a reflection region and displays an image for a second viewpoint. A display panel in which a plurality of display units are arranged in a matrix, and a plurality of lens elements that are arranged in front of the display panel and refract light emitted from the pixels and emit the light in different directions. The formed lens, a light source that irradiates light to the transmissive area of the display panel, and a reflection area in the display panel or a rear area of the reflection area of the display panel that reflects external light toward the lens And a reflecting plate having a concavo-convex shape on the surface, and the concavo-convex shape on the surface of the reflecting plate has a shape that reflects incident light a plurality of times.

  In the present invention, a part of the light reflected by one slope of the concavo-convex shape can travel in the direction of the observer after being re-reflected by another slope. Thereby, the brightness | luminance fall resulting from uneven | corrugated shape can be prevented.

  Furthermore, in the image display device according to the present invention, it is preferable that the concavo-convex shape has an inclination angle of 50 ° or more. Thereby, the brightness fall resulting from uneven | corrugated shape can be suppressed more.

  In the image display device according to the fifth aspect of the present invention, a plurality of display units including at least a pixel for displaying an image for a first viewpoint and a pixel for displaying an image for a second viewpoint are arranged in a matrix in one display unit. A display panel, a lenticular lens formed in front of the display panel and formed with a plurality of cylindrical lenses that refracts the light emitted from the pixels and emits the light in different directions; A reflector that is disposed behind the display panel and reflects external light toward the lens and has a concavo-convex shape on a surface thereof, and has an inclination angle in the concavo-convex shape in the arrangement direction of the cylindrical lenses. The existence probability is uniform in the pixels.

  The image display device according to the sixth aspect of the present invention is a pixel that includes a transmission area and a reflection area in one display unit and displays an image for a first viewpoint, and a pixel that includes a transmission area and a reflection area and displays an image for a second viewpoint. A display panel in which a plurality of display units are arranged in a matrix, and a plurality of cylindrical lenses that are arranged in front of the display panel and refract light emitted from the pixels and emit the light in different directions. The formed lenticular lens, a light source that irradiates light to the transmission area of the display panel, and a reflection area in the display panel or a rear area of the reflection area of the display panel that reflects external light toward the lens And a reflector having a concavo-convex shape on the surface, and a slope having a certain inclination angle in the concavo-convex shape in the arrangement direction of the cylindrical lenses. Probability characterized in that it is uniform in the pixels.

  Since the cylindrical lens does not have a lens effect in the longitudinal direction, the optical effect of the uneven shape in each pixel is obtained by integrating the effect in the longitudinal direction of the cylindrical lens. Therefore, if the existence probability of a slope having a certain inclination angle in the concavo-convex shape is made uniform in the pixel, the same inclination angle is continuously arranged at all positions in the arrangement direction of the cylindrical lenses. It is equivalent to the case. As a result, it is possible to prevent a decrease in luminance due to the uneven shape.

  Furthermore, in the image display device according to the present invention, it is preferable that the pitch of the uneven shape in the longitudinal direction of the cylindrical lens is smaller than the pitch of the uneven shape in the arrangement direction of the cylindrical lenses. Thereby, since the uneven shape can be arranged more densely in one pixel, application to a high-definition panel having a small pixel pitch is facilitated.

  In the image display device according to the present invention, it is preferable that the lens is a lenticular lens or a fly-eye lens. The display device may be a liquid crystal display device.

  A portable terminal device according to the present invention includes the above-described image display device. The mobile terminal device may be a mobile phone, a mobile terminal, a PDA (Personal Digital Assistance), a game machine, a digital camera, or a digital video.

  According to the present invention, since the light collected by the lens has a certain area on the surface of the reflector, it is reflected at a plurality of types of inclination angles such as uneven slopes and flat parts, and reflected light. Proceeds at various angles. This part also proceeds in the direction of the observer, and can contribute to display. As a result, it is possible to prevent a decrease in luminance due to the uneven shape, and it is possible to obtain an image display device having excellent display quality without a decrease in brightness in reflective display.

  Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings.

(First embodiment)
FIG. 1 is a cross-sectional view of a stereoscopic image display device according to a first embodiment of the present invention, and FIG. 2 is a perspective view showing a mobile terminal device according to the present embodiment. The stereoscopic image display device 1 includes a reflective liquid crystal display panel 2 and a lenticular lens 3. The reflective liquid crystal display panel 2 is configured by sandwiching a liquid crystal layer 5 between a substrate 6 and a transparent substrate 7, and a pixel electrode (reflecting plate 4) is formed on the surface of the substrate 6 on the liquid crystal layer side. A counter electrode (not shown) is formed on the surface of the transparent substrate 7 on the liquid crystal layer side. The pixel electrode and the counter electrode are linear electrodes extending in directions orthogonal to each other, and a pixel at a position where the pixel electrode and the counter electrode intersect is selected and a voltage is applied between them to align the liquid crystal. Is controlled to display an image.

  In the present embodiment, the reflection plate 4 is constituted by pixel electrodes arranged on the back side of the liquid crystal layer 5. This reflector has an uneven shape 41. The size of the concavo-convex shape 41 is the same as the concavo-convex shape of the reflection plate of the conventional reflective liquid crystal display device, but has a height of 2 μm and a pitch of 10 μm as an example.

  A lenticular lens 3 is disposed on the transparent substrate 7. The lenticular lens 3 is formed with a large number of curved surfaces (cylindrical surfaces) where the convex portions 31 appear at a constant pitch, and the longitudinal direction of the cylindrical surfaces (the direction in which the curved central axis extends) is, in this embodiment, It is parallel to the direction in which the pixel electrode (reflecting plate 4) extends. In addition, one cylindrical surface is arranged for two pixels (pixel electrodes 4).

  In the present embodiment, as described above, one display unit is composed of one left-eye pixel 4a and one right-eye pixel 4b, and each pixel emits from the left-eye pixel in each display unit. The emitted light and the light emitted from the right-eye pixel are distributed toward the left eye and the right eye by one corresponding cylindrical lens of the lenticular lens 3. In this case, external light passes through the lenticular lens 3, the transparent substrate 7 and the liquid crystal layer 5, and is reflected by the reflecting plate 4 located on the lower surface of the liquid crystal layer 5, and again, the liquid crystal layer 5, the transparent substrate 7 and the lenticular. It passes through the lens 3. At this time, external light incident on the reflecting plate 4 from a specific direction is diffused and reflected in various directions by the concave and convex shape 41 on the surface of the reflecting plate 4 and also reflected in the viewer direction. Thereby, reflection of a light source pattern can be prevented and external light having various angles can be utilized for display.

  Thus, in the present embodiment, the distance HR between the center of the convex portion 31 on the surface of the lenticular lens 3 and the surface of the reflector 4, that is, the pixel, is calculated using the conventional optical formulas 10 to 12. It is set to be larger than the distance H between the center of the convex portion on the surface of the lenticular lens 3 in the model and the pixel. As a result, the distance HR between the lens surface and the pixel is larger than the focal length f of the lenticular lens 3. In other words, in the present embodiment, the focal length f of the lenticular lens 3 is calculated by the above formulas 10 to 12 and 16. At this time, the observation distance OD is an optimum observation distance defined as follows, for example. The optimum observation distance is that the light emitted from the pixel displaying the image for the right eye is incident on the right eye by positioning the midpoint between the right eye and the left eye of the observer, and the left eye is The longest line among the line segments extending in the direction connecting the left-eye pixel 4a and the right-eye pixel 4b in one display unit in the stereoscopic visible range where the light emitted from the pixel displaying the left-eye image enters. The distance between the minute and the reflective liquid crystal display panel 2.

  The stereoscopic image display device 1 is used for, for example, image display of a mobile phone 9 as shown in FIG.

  Next, the results of a computer simulation performed to explain the effects of the present invention will be described. FIG. 3 shows an optical model used for computer simulation. In the conventional optical model of FIG. 31, the distance HR between the lens surface (convex center) and the pixel is set to 1.57 mm, which is equal to the focal length f of the lens = 1.57 mm. On the other hand, in the optical model of the present invention shown in FIG. 3, the distance HR between the lens surface (convex center) and the pixel is set to 1.77 mm, and the lens focal length f is greater than 1.57 mm. This is different from the case of FIG.

  FIG. 4A is a graph showing a simulation result when the optical model of FIG. 3 is used, and is a result when the present invention is applied. On the other hand, as a comparative example, FIG. 4B shows a simulation result when the conventional optical model of FIG. 31 is used. According to these figures, it can be seen that the decrease in luminance in the vicinity of −30 mm, which has occurred in FIG. 4B, is greatly alleviated in FIG. 4A. Therefore, the display does not become dark even when observed in the vicinity of −30 mm.

  5A and 5B are conceptual diagrams for qualitatively explaining the principle of the present invention. Among these, FIG. 5A is a conceptual diagram showing a trajectory of a ray 91 of a certain parallel light component in incident external light in the optical model shown in FIG. Since the distance H between the lens surface and the pixel is arranged so as to be equal to the focal length f, the light 91 collected by the lenticular lens 3 is focused on the surface of the reflecting plate 4 and has an uneven shape. When reflected by the slope, it travels in a direction different from the direction of the observer. For this reason, it does not contribute to display substantially. On the other hand, in the optical model of the present invention shown in FIG. 5B, since the distance HR between the lens surface and the pixel is set to be larger than the focal length f, the light condensed by the lenticular lens 3 is On the reflector 4, it has a certain area. As a result, since the light is reflected at a plurality of types of inclination angles such as an uneven slope and a flat portion, the reflected light travels at various angles. This part also proceeds in the direction of the observer, and can contribute to display. Therefore, according to the present invention, it is possible to prevent a decrease in luminance.

  Regarding the distance HR between the lens surface and the pixel, as shown in FIG. 6, it is particularly preferable that the light collected by the lenticular lens 3 irradiates the slopes having a plurality of inclination angles. As a result, the angular distribution of reflected light can be made wider, and the ratio of reflection in the observer direction can be increased. This condition is that when the pitch of the concavo-convex shape is V, a triangle having the lens pitch L as the base and the focal length f as the height, and the base V is the pitch V having the concavo-convex shape, and the height is the distance between the lens surface and the pixel. A similar relationship is established with the triangle, which is a value obtained by subtracting the focal length f from HR. Therefore, the condition for the light condensed by the lens to irradiate the inclined surfaces having a plurality of inclination angles is expressed by the following Expression 24. When this is modified, the following formula 25 is obtained.

  That is, it is preferable to set the distance HR between the lens surface and the pixel so as to satisfy Formula 25. In addition, when the position of the uneven shape is random, the present invention can be applied by setting V as the smallest pitch of the uneven shape.

  In the display element according to the present invention, it is only necessary that the pixel electrode has a reflection plate having an uneven shape. In the embodiment of the present invention, the case where the reflective liquid crystal display element is used has been described. However, the present invention is not limited to this, and for example, a display element using an electrophoretic phenomenon can be used. The uneven shape is applicable to any structure having a slope, and is not affected by the overall shape such as a dot shape, a rod shape, or a depression shape. The pixel electrode driving method may be an active matrix method such as a TFT method or a TFD method, or a passive matrix method such as an STN method.

  Further, the above description has been given for the case of a lenticular lens, but it goes without saying that it can also be applied to a fly-eye lens. FIG. 7 is a perspective view showing the fly-eye lens 10. As shown in FIG. 22, the lenticular lens 3 has a shape in which cylindrical lenses 3 extending in one direction are arranged in parallel to each other, in a direction connecting the left-eye pixel and the right-eye pixel in one display unit. That is, the convex surface is repeated in the left-right direction, and the surface does not change in the longitudinal direction of the lenticular lens 3 orthogonal to the left-right direction. That is, the shape of the cross section extending in the left-right direction does not change in the longitudinal direction of the lenticular lens 3. On the other hand, the fly-eye lens 10 has a convex surface that repeats in both the direction connecting the left-eye pixel and the right-eye pixel and the direction orthogonal to this direction. That is, in the direction (left-right direction) in which the left-eye pixel and the right-eye pixel in one display unit face each other, one convex surface is arranged for this set of left-eye pixel and right-eye pixel. This is the same as in the case of the lenticular lens, but the fly-eye lens also has one in every two pixels (two pixels for the right eye or two pixels for the left eye) in the direction orthogonal to the left-right direction. A number of convex surfaces are arranged.

  As a result, in the case of a fly-eye lens, when a stereoscopic image display device is set up and observed, a dedicated image is displayed on the left and right eyes to enable stereoscopic viewing. It is also possible to distribute the image in the direction to widen the viewing angle, or to allow the observer to see the upper and lower sides of the image. Thus, even when the fly-eye lens 10 is used as a lens, the focal length f of the lens is the distance H between the surface of the reflector and the center of the convex portion of the lens surface, as in the above embodiment. By making it different, it is possible to obtain the same effect as the above embodiment.

  In addition, the above description is about the case where the convex portion of the lens is arranged on the viewer side, but even when the convex portion of the lens is arranged on the display device side. The same effect can be obtained.

  The stereoscopic image display apparatus according to the present embodiment can be suitably applied to a portable device such as a mobile phone, and can display a favorable stereoscopic image. If the stereoscopic image display device according to the present embodiment is applied to a mobile device, unlike the case of applying to a large display device, the observer can arbitrarily adjust the positional relationship between his eyes and the display screen, which is optimal. A visible region can be quickly found.

  The stereoscopic image display apparatus according to the present embodiment can be applied not only to mobile phones but also to mobile terminal devices such as mobile terminals, PDAs, game machines, digital cameras, and digital video cameras.

(Second Embodiment)
FIG. 8 is a cross-sectional view of a stereoscopic image display apparatus according to the second embodiment of the present invention. In the present embodiment, the distance HR between the lens surface and the pixel is compared with the distance HR between the lens surface and the pixel in the conventional optical model calculated by Expressions 10 to 12 as compared with the first embodiment described above. The difference is that it is set smaller. As a result, the distance HR between the lens surface and the pixel is smaller than the focal length f of the lenticular lens.

  Regarding the distance HR between the lens surface and the pixel in the present embodiment, as shown in FIG. 9, it is particularly preferable that the light condensed by the lens irradiates a slope having a plurality of inclination angles. As a result, the angular distribution of reflected light can be made wider, and the ratio of reflection in the observer direction can be increased. This condition is expressed by the following formula 26 using the distance HR between the lens surface and the pixel, the focal length f, and the lens pitch L from the geometrical relationship, where V is the pitch of the concavo-convex shape. When this is modified, the following Expression 27 is obtained.

  That is, it is preferable to set the distance HR between the lens surface and the pixel so as to satisfy Expression 27. In addition, when the position of the uneven shape is random, the present invention can be applied by setting V as the smallest pitch of the uneven shape.

  According to the present invention, the distance between the lens surface and the pixel can be reduced as compared with the first embodiment of the present invention. Therefore, since the total thickness of the stereoscopic image display device can be reduced, it can be suitably used for a mobile terminal such as a mobile phone.

(Third embodiment)
FIG. 10 is a cross-sectional view of a stereoscopic image display apparatus according to the third embodiment of the present invention. Compared to the first embodiment of the present invention, the focal length fR of the lenticular lens in the present embodiment is set smaller than the focal length f in the conventional optical model calculated by the mathematical expressions 10 to 12 and 16. The distance H between the lens surface and the pixel is a value calculated by the equations 10 to 12.

  Regarding the focal length f in the present invention, as shown in FIG. 11, it is particularly preferable that the light condensed by the lens irradiates the slopes having a plurality of inclination angles. As a result, the angular distribution of reflected light can be made wider, and the ratio of reflection in the observer direction can be increased. This condition is expressed as the following Expression 28 using the distance H between the lens surface and the pixel, the focal length fR, and the lens pitch L from the geometrical relationship, where V is the pitch of the concavo-convex shape. By transforming this, the following formula 29 is obtained.

  That is, it is preferable to set the focal length fR of the lenticular lens so as to satisfy Equation 29. In addition, when the position of the concavo-convex shape is random, the present invention can be applied by setting the minimum pitch of the concavo-convex shape to V.

  The present embodiment has an advantage that it can be applied even when the distance between the lens surface and the pixel is fixed, as compared with the first embodiment. That is, in the first embodiment, since the distance H between the lens surface and the pixel is changed from a value satisfying Equations 1 to 9, it is necessary to redesign other parameters such as the observation distance OD. Further, when the redesign is not performed, the stereoscopic image display device is not in an ideal design state, and thus an adverse effect such as a shift of the stereoscopic visible range between the center portion and the end portion of the display screen occurs. In the present embodiment, such a problem does not occur because it is only necessary to change the focal length f.

(Fourth embodiment)
FIG. 12 is a cross-sectional view of a stereoscopic image display apparatus according to the fourth embodiment of the present invention. This embodiment differs from the third embodiment in that the focal length fR of the lenticular lens is set to be larger than the focal length f calculated by the equations 10 to 12 and 16, and the distance between the lens surface and the pixel. H is a point which is a calculated value in the conventional optical model calculated by the above formulas 10 to 12.

  Regarding the focal length f, as shown in FIG. 13, it is particularly preferable that the light collected by the lens irradiates the slopes having a plurality of inclination angles. As a result, the angular distribution of reflected light can be made wider, and the ratio of reflection in the observer direction can be increased. This condition is expressed by the following Equation 30 using the distance H between the lens surface and the pixel, the focal length fR, and the lens pitch L from the geometrical relationship, where V is the pitch of the concavo-convex shape. Further, when this is modified, the following formula 31 is obtained.

  That is, it is preferable to set the focal length fR of the lenticular lens so as to satisfy Formula 31. In addition, when the position of the uneven shape is random, the present invention can be applied by setting V as the smallest pitch of the uneven shape.

  According to the present embodiment, there is an advantage that the focal length fR can be set larger than that in the third embodiment of the present invention. As a result, the uneven height of the lens can be reduced, so that the lens pattern is less noticeable, and the display quality of the stereoscopic image is improved.

(Fifth embodiment)
FIG. 14 is a cross-sectional view of a stereoscopic image display apparatus according to the fifth embodiment of the present invention. This embodiment is different from the first to fourth embodiments in that the focal length f and the distance H between the lens surface and the pixel use the values calculated by the formulas 10 to 12 and 16, and the uneven shape. The inclination angle θ is set to 50 ° or more.

  In order to examine this embodiment in detail, a computer simulation was performed by changing the inclination angle θ of the concavo-convex shape between 25 ° and 75 °. FIG. 15 shows the simulation result. 15 (a) is θ = 75 °, FIG. 15 (b) is θ = 65 °, FIG. 15 (c) is θ = 60 °, FIG. 15 (d) is θ = 50 °, and FIG. FIG. 15F shows the results when θ = 35 ° and FIG. 15F. When the inclination angle θ is smaller than 50 °, the luminance decreases near −30 mm, but it can be seen that when the inclination angle θ is 50 ° or more, the luminance is greatly reduced. That is, the display does not become dark even when observed near -30 mm.

  FIG. 16 is a conceptual diagram for qualitatively explaining the principle of the embodiment of the present invention. Among these, FIG. 16A is a conceptual diagram showing the trajectory of a ray of a parallel light component of incident light in the conventional optical model shown in FIG. The distance H between the lens surface and the pixel is arranged to be equal to the focal length f, and the inclination angle of the concavo-convex shape is a value smaller than 50 °, for example, 30 °. In this case, the light collected by the lens travels in a direction different from the viewer's direction when reflected by the uneven slope. For this reason, it does not contribute to display substantially. On the other hand, in the optical model of this embodiment shown in FIG. 15B, the inclination angle of the concavo-convex shape is set to a value of 50 ° or more, for example, 60 °. As a result, a part of the light reflected on one slope of the concavo-convex shape travels in the direction of the observer after being reflected again on another slope. Accordingly, it is possible to prevent a decrease in luminance due to the uneven shape.

(Sixth embodiment)
Next, a sixth embodiment of the present invention will be described. FIG. 17 is a perspective view showing a stereoscopic image display apparatus according to the sixth embodiment of the present invention. FIGS. 18A and 18B are sectional views for qualitatively explaining the principle of the present embodiment. (A) is sectional drawing by the AA line shown in FIG. 17, (b) is sectional drawing by the BB line shown in FIG. The stereoscopic image display apparatus according to the present embodiment is an inclined surface having an inclination angle with a concavo-convex shape 41 in the arrangement direction of the cylindrical lenses 3a constituting the lenticular lens 3, as compared with the first to fifth embodiments described above. The difference is that the existence probability is substantially uniform in one pixel. The focal length f of the lenticular lens 3 is equal to the distance H between the lens surface of the lenticular lens 3 and the pixel, and the inclination angle of the concavo-convex shape 41 is, for example, 30 °.

  At the cross-sectional positions shown in FIGS. 18A and 18B, there are two types of positive and negative tilt angles in which the absolute values of the tilt angles of the concavo-convex shape 41 are equal to each other. And the position of the unevenness | corrugation in the sequence direction of the cylindrical lens 3a has shifted | deviated mutually by the half of the pitch of the uneven | corrugated shape 41, ie, a half cycle. That is, in the arrangement direction of the cylindrical lenses 3a, the phase of the concavo-convex shape 41 in the region shown in FIG. 18A and the phase of the concavo-convex shape 41 in the region shown in FIG. Yes.

  Since the cylindrical lens 3a does not have a lens function in the longitudinal direction, the optical effect of the concavo-convex shape 41 is obtained by integrating the effect in the longitudinal direction of the cylindrical lens 3a. Accordingly, in the stereoscopic image display device shown in FIGS. 17 and 18A and 18B, the optical effect of the uneven shape 41 is the same as the effect of the uneven shape 41 shown in FIG. The effect of the uneven shape 41 shown in b) is superimposed. As a result, positive and negative tilt angles always exist at any position in the longitudinal direction of the cylindrical lens 3a at any position in the arrangement direction of the cylindrical lenses 3a in one pixel. Accordingly, the optical characteristics of the stereoscopic image display apparatus according to the present embodiment are equivalent to the case where the same inclination angle is continuously arranged at all positions in the arrangement direction of the cylindrical lenses 3a.

  In FIG. 17, the number of irregularities is four, and two of them are arranged as a set and shifted by a half cycle, so that there is an inclined surface with the above inclination angle at an arbitrary position in the arrangement direction of the cylindrical lenses 3a. Probability is kept constant. Thereby, the brightness | luminance fall resulting from uneven | corrugated shape can be prevented more reliably.

  Furthermore, it is preferable that the concavo-convex shape 41 is arranged so as to be shifted in the arrangement direction of the cylindrical lenses 3a so as to be dense in the longitudinal direction of the cylindrical lenses 3a. For example, when the concavo-convex shape 41 is a conical shape, a plurality of cones are arranged in one row in the arrangement direction of the cylindrical lenses 3a, and the cones in the next row enter between the cones adjacent to each other in the arrangement direction. It may be arranged. In this way, the pitch of the concavo-convex shape 41 in the longitudinal direction of the cylindrical lens 3a can be made smaller than the pitch of the concavo-convex shape 41 in the arrangement direction of the cylindrical lenses 3a. As a result, in the longitudinal direction of the cylindrical lens 3a, the number of the concavo-convex shapes 41 arranged in one pixel increases, and the reflected light can be made more uniform due to the integration effect described above. For this reason, it becomes much easier to apply the stereoscopic image display apparatus according to the present embodiment to a high-definition panel having a small pixel pitch.

  The focal length f of the lenticular lens 3 may be different from the distance H between the lens surface of the lenticular lens 3 and the pixel, and the inclination angle of the concavo-convex shape 41 may be 50 ° or more, for example. In addition, the stereoscopic image display device according to the present embodiment may be a transflective device in which a reflective region and a transmissive region are provided in each pixel.

(Seventh embodiment)
FIG. 19 is a perspective view of a stereoscopic image display apparatus according to the seventh embodiment of the present invention. The display panel 200 of the stereoscopic image display device 1 in this embodiment is a transflective display element in which the pixel electrode has a transmissive region and a reflective region. Specifically, the left-eye pixel is composed of a left-eye pixel (transmission area) 511 and a left-eye pixel (reflection area) 512. Similarly, the right-eye pixel is a right-eye pixel (transmission area). Area) 521 and a right eye pixel (reflection area) 522. The pixel electrodes of the left-eye pixel (reflection area) 512 and the right-eye pixel (reflection area) 522 are reflection plates formed of a non-transparent layer such as a metal electrode. As described above, an uneven shape is provided. The relationship between the uneven shape of the reflecting plate and the lenticular lens 3 is the same as in the first to fifth embodiments of the present invention described above. Further, the pixel electrodes of the left-eye pixel (transmission region) 511 and the right-eye pixel (transmission region) 521 are made of transparent electrodes such as ITO (indium-tin-oxide). Further, a backlight light source (not shown) for the transmissive region is provided below these display panels.

  In the stereoscopic image display apparatus according to the present embodiment configured as described above, the transmission area can transmit light from the backlight light source, and the reflection area can reflect outside light such as natural light and room illumination light. A transmissive display and a reflective display can be realized. As a result, a clear display can be performed regardless of the surrounding brightness level.

  In the present embodiment, a transflective display element has been described. However, the present invention is also applicable to a microtransmission display element, a microreflection display element, and the like.

(Eighth embodiment)
Next, an eighth embodiment of the present invention will be described. FIG. 20 is a perspective view showing the portable terminal device according to the present embodiment, and FIG. 21 is an optical model diagram showing the operation of the image display device according to the present embodiment. As shown in FIG. 20, in the present embodiment, an image display device is incorporated in a mobile phone 9 as a mobile terminal device. In this embodiment, the longitudinal direction 11 of the cylindrical lens 3a constituting the lenticular lens 3 is the horizontal direction of the image display device, that is, the horizontal direction of the image, compared with the first embodiment described above. The difference is that the arrangement direction 12 of the lenses 3a is the vertical direction, that is, the vertical direction of the image. In FIG. 20, only four cylindrical lenses 3 a are shown for simplification of illustration, but in reality, the cylindrical lenses 3 a are formed by the number of pixels arranged in the longitudinal direction 11.

  Further, as shown in FIG. 21, the display panel 2 has a plurality of pixel pairs each including a first viewpoint pixel 53 and a second viewpoint pixel 54 arranged in a matrix. The arrangement direction of the first viewpoint pixel 53 and the second viewpoint pixel 54 in one pixel pair is the arrangement direction 12 of the cylindrical lenses 3a, that is, the vertical direction (vertical direction) of the screen. Other configurations in the present embodiment are the same as those in the first embodiment.

  Next, the operation of the image display apparatus according to this embodiment will be described. As shown in FIG. 21, the first viewpoint pixel 53 of the reflective display panel 2 displays a first viewpoint image, and the second viewpoint pixel 54 displays a second viewpoint image. The image for the first viewpoint and the image for the second viewpoint are not stereoscopic images with parallax but are planar images. Moreover, although both images may be images independent from each other, they may be images indicating information related to each other.

  Then, external light such as natural light and illumination light passes through the lenticular lens 3 from the front, enters the liquid crystal display panel 2, is reflected by the pixels 53 and 54, and travels toward the lenticular lens 3. The light reflected by the first viewpoint pixel 53 and the second viewpoint pixel 54 is refracted by the cylindrical lens 3a and is emitted toward the regions E1 and E2, respectively. At this time, when the observer places both eyes in the region E1, the image for the first viewpoint can be observed, and when both eyes are located in the region E2, the image for the second viewpoint is displayed. The image can be observed.

  In the present embodiment, the observer simply changes the angle of the mobile phone 9 to position his / her eyes in the region E1 or the region E2 and select an image for the first viewpoint or an image for the second viewpoint. There is an advantage that it can be observed. In particular, when there is a relationship between the image for the first viewpoint and the image for the second viewpoint, each image can be switched and observed alternately by a simple method of changing the observation angle. Is greatly improved. In addition, when the image for the first viewpoint and the image for the second viewpoint are arranged in the horizontal direction, different images may be observed for the right eye and the left eye depending on the observation position. In this case, the observer is confused and cannot recognize the image of each viewpoint. On the other hand, as shown in this embodiment, when images for a plurality of viewpoints are arranged in the vertical direction, the observer can always observe the images for each viewpoint with both eyes, so that these images can be easily viewed. Can be recognized. The effects of the present embodiment other than those described above are the same as those of the first embodiment described above. Note that this embodiment can be combined with any one of the second to sixth embodiments described above.

  In the first to eighth embodiments described above, a stereoscopic image is displayed by supplying an image with parallax to the left and right eyes of one observer mounted on a mobile phone or the like. Although an example of an image display device that supplies a plurality of types of images to a human observer at the same time is shown, the image display device according to the present invention is not limited to this, and includes a large display panel, and a plurality of viewers can interact with each other. A plurality of different images may be supplied.

1 is a cross-sectional view illustrating a stereoscopic image display device according to a first embodiment of the present invention. It is a perspective view which shows the portable terminal device which concerns on the 1st Embodiment of this invention. In the 1st Embodiment of this invention, it is an optical model figure for performing computer simulation. In the 1st Embodiment of this invention, it is the graph which showed the result of the computer simulation. It is a conceptual diagram for showing the principle of the 1st Embodiment of this invention. In the 1st Embodiment of this invention, it is sectional drawing which shows the state which the light condensed with the lens irradiates a several inclined surface. It is a perspective view which shows the fly eye lens used instead of a lenticular lens. It is sectional drawing which shows the 2nd Embodiment of this invention. In the 2nd Embodiment of this invention, it is sectional drawing which shows the state which the light condensed with the lens irradiates a several inclined surface. It is sectional drawing which shows the 3rd Embodiment of this invention. In the 3rd Embodiment of this invention, it is sectional drawing which shows the state which the light condensed with the lens irradiates a several inclined surface. It is sectional drawing which shows the 4th Embodiment of this invention. In the 4th Embodiment of this invention, it is sectional drawing which shows the state which the light condensed with the lens irradiates a several inclined surface. It is sectional drawing which shows the 5th Embodiment of this invention. In the 5th Embodiment of this invention, it is the graph which showed the result of the computer simulation. It is a conceptual diagram for showing the principle of the 5th Embodiment of this invention. It is a perspective view which shows the three-dimensional image display apparatus which concerns on the 6th Embodiment of this invention. (A) And (b) is sectional drawing for qualitatively explaining the principle of this embodiment, (a) is sectional drawing by the AA line shown in FIG. 17, (b) FIG. 18 is a cross-sectional view taken along line BB shown in FIG. It is a typical perspective view which shows the 7th Embodiment of this invention. It is a perspective view which shows the portable terminal device which concerns on the 8th Embodiment of this invention. It is an optical model figure which shows operation | movement of the image display apparatus which concerns on this embodiment. 2 is a perspective view showing the shape of a lenticular lens 3. FIG. It is an optical model figure which shows the three-dimensional image display method which uses the conventional lenticular lens. It is an optical model figure which shows the stereoscopic image display method using the conventional parallax barrier. It is a conceptual diagram for showing the reflecting plate which has the conventional uneven | corrugated shape. It is a perspective view which shows the stereo image display apparatus using the conventional lenticular lens and a display element. It is sectional drawing in the stereoscopic image display apparatus using the conventional lenticular lens and a display element. It is a model figure which shows the size of each part in the stereo image display apparatus using the conventional lenticular lens and a display element. It is an optical model diagram for performing computer simulation in a conventional stereoscopic image display device using a lenticular lens and a display element. It is the graph which showed the result of the computer simulation in the stereoscopic image display apparatus using the conventional lenticular lens and the display element. It is an optical model diagram for performing a computer simulation when a reflector having a concavo-convex shape is applied to a stereoscopic image display device using a conventional lenticular lens and a display element. It is the graph which showed the result of the computer simulation at the time of applying the reflecting plate which has uneven | corrugated shape in the stereo image display apparatus using the conventional lenticular lens and a display element.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1; Stereoscopic image display apparatus 2; Reflection type liquid crystal display panel 200: Transflective type liquid crystal display panel 3, 121; Lenticular lens 3a; Cylindrical lens 31, 122: Convex part 4; Reflection plate 41: Concave shape 4a: For left eye Pixel 4b: Pixel for right eye 5: Liquid crystal layer 6: Substrate 7: Transparent substrate 8: Observation position 9; Cellular phone 91: Light beam 10: Fly eye lens 11; Longitudinal direction of cylindrical lens 12: Arrangement direction of cylindrical lens 17; Light emitting area 18; Light receiving surface 19; Light source 31; Convex portion 41; Concave and convex shape 42; Shading portion 51; Pixel for left eye 52; Pixel for right eye 53; Pixel for first viewpoint 54; Left eye 62, 141; right eye 105; parallax barrier 105a; slit 106: display panel 107; stereoscopic view area 107a; 107 b; optimum viewing plane 108: light source 123: pixel 143; right eye 141 and left eye 142 and the midpoint 181 and 182; the light beam 511: left-eye pixel (transmission region)
512: Pixel for left eye (reflection area)
521: Pixel for right eye (transmission region)
522: Right-eye pixel (reflection area)

Claims (17)

  A display panel in which a plurality of display units including at least a pixel for displaying an image for a first viewpoint and a pixel for displaying an image for a second viewpoint are arranged in a matrix in one display unit, and in front of the display panel A lens formed with a plurality of lens elements that refracts the light emitted from each pixel and emits the light in different directions; and the outside light disposed in the display panel or behind the display panel. A reflecting plate having a concavo-convex shape on the surface thereof, and the focal length f of the lens is different from the distance H between the surface of the reflecting plate and the apex of the lens, and the concavo-convex shape An image display device that suppresses deterioration in image quality due to a combination of the lens and the lens.   A plurality of display units each including at least a pixel that includes a transmission area and a reflection area in one display unit and displays an image for the first viewpoint, and a pixel that includes the transmission area and the reflection area and displays an image for the second viewpoint. A display panel disposed in front of the display panel, a lens formed in front of the display panel and formed with a plurality of lens elements that refract light emitted from the pixels and emit the light in different directions, and the display panel A light source that irradiates light to the transmissive region, and a reflector that is disposed behind the reflective region in the display panel or the reflective region of the display panel and diffuses and reflects external light toward the lens and has an uneven shape on the surface And the focal length f of the lens is different from the distance H between the surface of the reflector and the apex of the lens, and the image quality deteriorates due to the combination of the uneven shape and the lens. An image display device comprising suppressing.   3. The image display device according to claim 1, wherein a focal length f of the lens is smaller than a distance H between a surface of the reflecting plate and a vertex of the lens. The concavo-convex shape is a structure having an inclined surface, and a convex portion of the surface of the lens in a first direction from a pixel displaying the image for the first viewpoint to a pixel displaying the image for the second viewpoint. When the pitch is L and the minimum value of the distance between the convex and concave portions of the reflector in the first direction is V, the focal length f of the lens, the surface of the reflector and the vertex of the lens The image display device according to claim 3, wherein a distance H between the two satisfies the following mathematical formula.

  3. The image display device according to claim 1, wherein a focal length f of the lens is larger than a distance H between a surface of the reflecting plate and a vertex of the lens. The concavo-convex shape is a structure having an inclined surface, and a convex portion of the surface of the lens in a first direction from a pixel displaying the image for the first viewpoint to a pixel displaying the image for the second viewpoint. When the pitch is L and the minimum value of the distance between the convex and concave portions of the reflector in the first direction is V, the focal length f of the lens, the surface of the reflector and the vertex of the lens The image display device according to claim 5, wherein the distance H between the two satisfies the following mathematical formula.

  A display panel in which a plurality of display units including at least a pixel for displaying an image for a first viewpoint and a pixel for displaying an image for a second viewpoint are arranged in a matrix in one display unit, and in front of the display panel A lens formed with a plurality of lens elements that refracts the light emitted from each pixel and emits the light in different directions; and the outside light disposed in the display panel or behind the display panel. A reflection plate having a concavo-convex shape on the surface thereof, and having a shape that reflects and diffuses light incident multiple times on the surface of the reflection plate. An image display device.   A plurality of display units including a pixel that includes a transmission region and a reflection region in one display unit and displays an image for the first viewpoint, and a pixel that includes a transmission region and a reflection region and displays an image for the second viewpoint are arranged in a matrix. A display panel disposed in front of the display panel; a lens formed with a plurality of lens elements that refract light emitted from the pixels and radiate the light in different directions; and the display panel A light source that irradiates light to a transmission region, and a reflection plate that is disposed behind the reflection region in the display panel or the reflection region of the display panel and diffuses and reflects external light toward the lens and has an uneven shape on the surface The image display device is characterized in that the concave and convex shape on the surface of the reflecting plate has a shape that reflects and diffuses the incident light a plurality of times.   The image display device according to claim 11 or 12, wherein the uneven shape has a structure having a slope, and an inclination angle of the slope is 50 ° or more.   A display panel in which a plurality of display units including at least a pixel for displaying an image for a first viewpoint and a pixel for displaying an image for a second viewpoint are arranged in a matrix in one display unit, and in front of the display panel A lenticular lens formed with a plurality of cylindrical lenses that refracts the light emitted from each pixel and emits the light in different directions, and the external light disposed in the display panel or behind the display panel. A reflector having a concavo-convex shape having a slope on the surface and diffusely reflecting toward the lenticular lens, and the existence probability of a slope having a certain inclination angle in the concavo-convex shape in the arrangement direction of the cylindrical lens is the pixel. The density of the uneven shape in the longitudinal direction of the cylindrical lens is uniform in the cylindrical lens An image display device comprising less than the density of the irregularities in the arrangement direction.   A plurality of display units including a pixel that includes a transmission area and a reflection area in one display unit and displays an image for a first viewpoint, and a pixel that includes a transmission area and a reflection area and displays an image for a second viewpoint are arranged in a matrix. A display panel disposed in front of the display panel, a lenticular lens formed with a plurality of cylindrical lenses that refract light emitted from the pixels and radiate the light in different directions, and the display panel. A light source that irradiates light to the transmissive region, and an uneven shape that is disposed behind the reflective region in the display panel or the reflective region of the display panel and diffuses and reflects external light toward the lenticular lens and has a slope on the surface And a probability of existence of a slope having an inclination angle in the concavo-convex shape in the arrangement direction of the cylindrical lenses. Wherein a uniform in the pixels, the density of the irregularities in the longitudinal direction of the cylindrical lens, the image display apparatus and is smaller than the density of the irregularities in the arrangement direction of the cylindrical lens.   A display panel in which a plurality of display units including at least a pixel for displaying an image for a first viewpoint and a pixel for displaying an image for a second viewpoint are arranged in a matrix in one display unit, and in front of the display panel A lens formed with a plurality of lens elements that refracts the light emitted from each pixel and emits the light in different directions; and the outside light disposed in the display panel or behind the display panel. A reflector having a concavo-convex shape on the surface thereof, and the focal length f of the lens is different from the distance H between the surface of the reflector and the apex of the lens, and the reflector An image display device characterized by having a shape that reflects and diffuses incident light a plurality of times, with the irregular shape on the surface thereof.   A display panel in which a plurality of display units including at least a pixel for displaying an image for a first viewpoint and a pixel for displaying an image for a second viewpoint are arranged in a matrix in one display unit, and in front of the display panel A lenticular lens formed with a plurality of cylindrical lenses that refracts the light emitted from each pixel and emits the light in different directions, and the external light disposed in the display panel or behind the display panel. A reflecting plate that diffusely reflects toward the lenticular lens and has a concavo-convex shape having a slope on the surface, and the focal length f of the cylindrical lens is a distance between the surface of the reflecting plate and the apex of the cylindrical lens Unlike H, in the arrangement direction of the cylindrical lenses, the existence probability of an inclined surface having a specific inclination angle in the uneven shape is An image display device comprising that it is uniform in the serial pixel.   The first viewpoint image is a left-eye image, the second viewpoint image is a right-eye image having a parallax with respect to the left-eye image, and displays a stereoscopic image. The image display device according to claim 1, wherein:   The image display device according to claim 1, wherein the display device is a liquid crystal display device.   A portable terminal device comprising the image display device according to claim 1.   The mobile terminal device according to claim 16, wherein the mobile terminal device is a mobile phone, a mobile terminal, a PDA, a game machine, a digital camera, or a digital video.

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