JP4433724B2 - Stereoscopic image display device - Google Patents

Description

The present invention relates to a stereoscopic image display device .

Conventionally, as a liquid crystal display device for displaying a stereoscopic image, an image for the left eye is displayed by every other column of pixels of the liquid crystal display panel, and an image for the right eye is displayed by every other column of pixels. And right-eye images are divided into the left-eye direction and the right-eye direction of the display observer for the light emitted from the pixels in one row and the light from the pixels in the other row of the liquid crystal display panel. Alternatively, the left and right eyes of the observer can be observed through a parallax barrier in which a plurality of transmissive parts and light-shielding parts parallel to the pixel rows of the liquid crystal display panel are alternately arranged. (See Patent Documents 1, 2, and 3).
Japanese Laid-Open Patent Publication No. 3-19889 JP-A-7-005400 Japanese Patent Laid-Open No. 10-268230

  However, since a conventional liquid crystal display device that displays a stereoscopic image displays an image for the left eye by every other row of pixels of the liquid crystal display panel and an image for the right eye by every other row of pixels, The image resolution is low.

  Moreover, in the conventional liquid crystal display device, a lenticular lens having a lens pitch corresponding to the pixel pitch of the liquid crystal display panel, or a parallax barrier having a transmissive portion pitch corresponding to the pixel pitch, and each lens portion or transmissive portion of the lenticular lens are The pixels in each row of the liquid crystal display panel must be arranged with high precision in a predetermined positional relationship, and thus manufacturing is difficult.

An object of the present invention is to provide a stereoscopic image display device that can display a stereoscopic image with high resolution and can be easily manufactured.

In order to achieve the above object, the invention according to claim 1 includes a liquid crystal display panel having a plurality of pixels and alternately displaying a left-eye image and a right-eye image on each pixel in a time-division manner. From the first illumination light having a peak of emitted light intensity in a first direction inclined at a first predetermined angle toward the predetermined direction from the normal line of the liquid crystal display panel, and the normal line of the liquid crystal display panel The left-eye image and the right-eye that are alternately displayed are the second illumination light in which the peak of the emitted light intensity exists in the second direction inclined at the second predetermined angle to the side different from the predetermined direction side. A surface light source that emits light toward the liquid crystal display panel alternately in a time-division manner in synchronization with a display switching timing with a display image, wherein the surface light source is the liquid crystal display panel A light guide plate arranged to face the first light guide plate, and a first light guide plate A first light emitting element that causes light to enter the light guide plate from an end face; a second light emitting element that causes light to enter the light guide plate from a second end face that faces the first end face; the light guide plate; A pair of single-sided prism sheets disposed between the liquid crystal display panel and formed with a plurality of elongated prisms extending in a direction parallel to the first end surface and the second end surface on one surface. In the pair of single-sided prism sheets, the elongated prisms are arranged at equal intervals between the pair of single-sided prism sheets, and the apex angles of the corresponding elongated prisms coincide with each other on the normal line. It is arranged so that it may be arranged.

The invention according to claim 2 is the stereoscopic image display device according to claim 1, wherein the pair of single-sided prism sheets are arranged such that surfaces on which the elongated prisms are formed face each other. Features.
According to a third aspect of the present invention, in the three-dimensional image display device according to the first or second aspect, the first illumination light has a peak of emitted light intensity from the normal line of the liquid crystal display panel. The light from the first light emitting element is light distributed by the light guide plate and the pair of single-sided prism sheets so that the first predetermined angle is inclined to the side where the light emitting element is disposed. The second illumination light includes the second illumination light such that the peak of the emitted light intensity is inclined from the normal line of the liquid crystal display panel to the side where the second light emitting element is disposed by the second predetermined angle. The light from the light emitting element is light distributed by the light guide plate and the pair of single-sided prism sheets.
According to a fourth aspect of the present invention, in the stereoscopic image display device according to the third aspect, the light from the first light emitting element is the one adjacent to the light guide plate in the pair of single-sided prism sheets. At the time of emission from the single-sided prism sheet, the peak of the emitted light intensity is in a direction inclined from the normal line of the liquid crystal display panel to the side where the second light emitting element is disposed, and the light from the second light emitting element When the light is emitted from the single-sided prism sheet adjacent to the light guide plate of the pair of single-sided prism sheets, the peak of the emitted light intensity is arranged from the normal line of the liquid crystal display panel, and the first light emitting element is disposed. It is characterized in that it is in a direction inclined to the side.

The invention according to claim 5 is the stereoscopic image display device according to any one of claims 1 to 4, wherein each of the pair of single-sided prism sheets has an apex angle in a range of 70 ° to 100 °. It is characterized by being set.
According to a sixth aspect of the present invention, in the stereoscopic image display device according to any one of the first to fifth aspects of the present invention, the pair of single-sided prism sheets each have an arrangement interval of the elongated prisms equal to a pixel arrangement interval. It is characterized by being equal.

Further, according to claim 7 invention have a plurality of pixels, the liquid crystal display panel for displaying the divided alternately when a left eye image and a right eye image, a predetermined from the normal of the liquid crystal display panel A first illumination light having a peak of emitted light intensity in a first direction inclined to the direction side by a first predetermined angle, and a normal line of the liquid crystal display panel to a side different from the predetermined direction side . A second illumination light having a peak of emitted light intensity in a second direction inclined at a predetermined angle of 2 and a surface light source that alternately emits the light toward the liquid crystal display panel in a time-sharing manner, A stereoscopic image display device that synchronizes the emission switching timing of the first illumination light and the second illumination light and the display switching timing of the left-eye image and the right-eye image , wherein the surface light source is A light guide plate disposed to face the liquid crystal display panel; A first light emitting element that makes light incident on the light guide plate from the first end face of the light guide plate, and a second light emitting element that makes light incident on the light guide plate from a second end face facing the first end face And a pair of single-sided surfaces, which are disposed between the light guide plate and the liquid crystal display panel, and are formed on one surface with a plurality of elongated prisms extending in a direction parallel to the first end surface and the second end surface. The pair of single-sided prism sheets are arranged so that the elongated prisms are arranged at equal intervals between the pair of single-sided prism sheets, and the apex angles of the elongated prisms correspond to each other. Are arranged so as to coincide with each other on the normal line.
The invention according to claim 8 is the stereoscopic image display device according to any one of claims 1 to 7, wherein the first predetermined angle is equal to the second predetermined angle. To do.

According to the present invention, a high-resolution stereoscopic image can be displayed and can be easily manufactured.

  1 to 5 show an embodiment of the present invention, FIG. 1 is an exploded perspective view of a liquid crystal display device, FIG. 2 is a side view of the liquid crystal display device, and FIG. 3 is a surface light source of the liquid crystal display device. It is an enlarged side view of a part.

  This liquid crystal display device has a plurality of pixels as shown in FIGS. 1 to 3, and image data for the left eye and right eye for observation with the left and right eyes are selectively selected in these pixels. A liquid crystal display panel 1 that is written and selectively displays a left-eye image and a right-eye image in accordance with the left-eye and right-eye image data, and the observation side of the liquid crystal display panel 1 (see FIG. Is arranged on the opposite side (hereinafter referred to as the incident side) and predetermined in the direction of one of the left and right eyes of the display observer with respect to the normal H of the liquid crystal display panel 1. The first illumination light having directivity in which the peak of the emitted light intensity exists in the first direction inclined to the angle, and the predetermined angle inclination with respect to the normal H in the direction of the other eye of the observer The second illumination light having directivity in which the peak of the emitted light intensity exists in the second direction is alternately displayed on the liquid crystal display. A surface light source 6 that emits toward the panel 1, and a control unit 15 for driving the liquid crystal display panel 1 and the surface light source 6.

  The liquid crystal display panel 1 is an active matrix liquid crystal display panel having TFTs (thin film transistors) as active elements, for example, and the internal structure is not shown, but a pair of transparent substrates 2 joined through a frame-shaped sealing material 2 3, a plurality of transparent pixel electrodes arranged in a matrix in the row direction and the column direction on one substrate, for example, a surface of the incident side substrate 2 facing the observation side substrate 3, and connected to these pixel electrodes, respectively. A plurality of TFTs, a plurality of gate wirings for supplying gate signals to the TFTs in each row, and a plurality of gate wirings for supplying gate signals to the TFTs in each column, respectively. 3) Forming a plurality of pixels arranged in a matrix in a region facing each of the plurality of pixel electrodes on the surface of the substrate 3 facing the incident side substrate 2 A transparent counter electrode in the form of a single film is provided, a liquid crystal layer is provided in a region surrounded by the sealing material between the substrates 2 and 3, and one of the opposing surfaces of the pair of substrates 2 and 3 On the other hand, a plurality of colors, for example, three color filters of red, green, and blue, are provided so that the plurality of pixel electrodes and the counter electrode face each other. .

  The incident-side substrate 2 has driver mounting portions 2a and 2b extending outward from the observation-side substrate 3 at one end edge in the row direction and one end edge in the column direction, and the plurality of gates The wiring is connected to the gate side driver 4 mounted on the driver mounting portion 2a in the row direction, and the plurality of data wirings are connected to the data side driver 5 mounted on the driver mounting portion 2b in the column direction. The electrode is connected to the gate driver 4 and the data driver 5 via a cross connection portion provided at a substrate bonding portion by the sealing material and a counter electrode connection wiring formed on one or both of the driver mounting portions 2a and 2b. Are connected to one or both of the reference potentials.

  The liquid crystal display panel 1 is, for example, a TN (twisted nematic) type in which the liquid crystal molecules of the liquid crystal layer are twist-aligned with a twist angle of substantially 90 ° between the pair of substrates 2 and 3. Although not shown in the figure, the incident-side polarizing plate and the display-side polarizing plate are arranged on the outer surfaces of the pair of substrates 2 and 3 so that their transmission axes are substantially orthogonal or substantially parallel to each other. Has been.

  The liquid crystal display panel 1 may be of a non-twisted homogeneous alignment type in which the liquid crystal molecules of the liquid crystal layer are aligned homogeneously with the molecular long axis aligned in one direction. , 3 are preferably arranged so that the incident-side polarizing plate and the display-side polarizing plate constitute a normally white mode liquid crystal display element with their respective transmission axes directed in a predetermined direction.

  The surface light source 6 is formed of a rectangular plate-shaped transparent member, and is formed on the opposite end surfaces of the transparent member. The first and second incident end surfaces 8a and 8b, on which light is incident, and the first and first surfaces. 2 is incident on the incident end faces 8a and 8b and emits the light guided in the transparent member in different directions, and the light incident on the transparent member from the incident end faces 8a and 8b is the exit surface. The light guide plate 7 having a reflection surface 10 that reflects toward the light source 9 and the first and second light-emitting plates 7 that are disposed opposite to the first and second incident end surfaces 8a and 8b of the light guide plate 7 and are alternately lit. Two light emitting elements 11a and 11b and the light exiting surface 9 side of the light guide plate 7, enter the light guide plate 7 from the first and second incident end surfaces 8a and exit from the exit surface 9 The light is refracted and the first direction (with respect to the normal H of the liquid crystal display panel 1) The first illumination light having directivity in which the peak of the emitted light intensity exists in a direction inclined at a predetermined angle in the direction of one of the left and right eyes of the display observer. The light incident on the light plate 7 from the other incident end surface 8b and refracted from the exit surface 9 is refracted to the second direction (the direction of the other eye of the display observer with respect to the normal H of the liquid crystal display panel 1). And a light refracting means 12 for emitting the second illumination light having directivity in which the peak of the emitted light intensity exists in a direction inclined at a predetermined angle.

  The light guide plate 7 has a width and length larger than the vertical and horizontal widths of the display area A of the liquid crystal display panel 1 (a region in which a plurality of pixels are arranged in a matrix), and the longitudinal direction thereof, That is, the direction orthogonal to the first and second incident end faces 8a and 8b is substantially parallel to the horizontal axis of the display area A of the liquid crystal display panel 1, and the normal h of the exit surface 9 is The liquid crystal display panel 1 is arranged in parallel with the liquid crystal display panel 1 so as to coincide with the normal line H of the liquid crystal display panel 1.

  The light guide plate 7 is made of a plate-like member having a thickness of 0.8 mm to 2.0 mm in which a light diffusion filler is dispersed in a transparent resin such as acrylic, polycarbonate, norbornene, and is omitted in the drawing. However, the reflective surface 10 of the light guide plate 7 has a plurality of elongated grooves having an isosceles triangle cross section along the direction parallel to the first and second incident end surfaces over the entire region of about 50 μm to 100 μm. Are formed in parallel with each other.

  Each of the first and second light emitting elements 11a and 11b is a solid light emitting element composed of an LED (light emitting diode), and its internal structure is not shown, but a red LED that emits red light and green light is emitted. A green LED and a blue LED that emits blue light are provided, and white light a and b obtained by mixing three colors of red, green, and blue light from these LEDs are directed toward the incident end faces 8a and 8b of the light guide plate 7. And exit.

  The first and second light emitting elements arranged to face the first and second incident end faces 8a and 8b of the light guide plate 7 may be cold cathode tubes that emit white light.

  The light guide plate 7 emits the light a emitted from the first light emitting element 11a and incident from the first incident end face 8a, and the second incident end face emitted from the second light emitting element 11b. The light b incident from 8b is emitted from the emission surface 9 in different directions.

  That is, the light a and b incident on the light guide plate 7 from the first and second incident end faces 8a and 8b are respectively diffused by the light diffusing filler, and are emitted from the emission surface 9 and the outside air (air layer). The plurality of elongated grooves formed on the reflecting surface 10 from the entire area of the light emitting surface 9 by being totally reflected at the interface and the interface between the reflecting surface 10 and the outside air and guided in the length direction in the light guide plate 7. The light having directivity in the direction of the angle range defined by the inclination angle of both side surfaces of the light is emitted with a substantially uniform intensity.

  The light a incident from the first incident end face 8a and exiting from the exit surface 9 is in the longitudinal direction of the light guide plate with respect to the normal h of the exit surface 9 (the horizontal axis direction of the display area A of the liquid crystal display panel 1). A light having directivity in a direction inclined in the direction opposite to the first incident end face 8a (the second incident end face 8b side) along the second incident end face 8b and incident from the second incident end face 8b. The light b emitted from the light beam is directed in a direction inclined to the direction opposite to the second incident end face 8b (on the first incident end face 8a side) along the longitudinal direction of the light guide plate with respect to the normal h of the outgoing face 9. The light a and b are emitted at emission angles α1 and α2 in an angle range of 50 ° to 80 ° with respect to the normal h of the emission surface 9.

  FIG. 4 shows light a incident on the light guide plate 7 from the first incident end surface 8a and emitted from the exit surface 9, and incident on the light guide plate 7 from the second incident end surface 8b and emerged from the exit surface 9. The luminance distribution of the emitted light b viewed from the emission side (the liquid crystal display panel 1 side) is shown. In the figure, the positive emission angle is a right angle with respect to the normal h of the emission surface 9 and is a negative emission. The angle is an angle in the left direction with respect to the normal h.

  The light refracting means 12 disposed on the light exit surface 9 side of the light guide plate 7 is disposed to face the light exit surface 9 of the light guide plate 7, and the first and second surfaces of the light guide plate 7 are disposed on one surface. The first prism sheet 13 formed with a plurality of elongated prism portions 13a parallel to the incident end faces 8a and 8b of the first prism sheet 13 is disposed on the opposite side to the light guide plate 7 side of the first prism sheet 13, and one surface thereof And a second prism sheet 14 formed with a plurality of elongated prism portions 14a parallel to the elongated prism portions 13a of the first prism sheet 13.

  The first and second prism sheets 13 and 14 are transparent resin films (for example, acrylic resins) having a refractive index of 1.4 to 1.6 having an area facing the entire display area A of the liquid crystal display panel 1. The plurality of elongated prism portions 13a and 14a are densely arranged in parallel with each other over the entire area of one surface thereof.

  Each of the plurality of elongated prism portions 13a and 14a of the prism sheets 13 and 14 has an isosceles triangular cross-sectional shape, and apex angles θ1 and θ2 are set in a range of 70 ° to 100 °, respectively. ing.

  For the sake of convenience, the plurality of elongated prism portions 13a and 14a of the prism sheets 13 and 14 are greatly exaggerated in the drawing, but the plurality of elongated prism portions 13a and 14a are arranged in the row direction of the liquid crystal display panel 1. It is formed at a pitch that is the same as or smaller than the pixel pitch (80 μm to 100 μm) in the direction along the horizontal axis of the display area A.

  The pitches of the plurality of elongated prism portions 13a and 14a of the first and second prism sheets 13 and 14 are substantially the same, and the first prism sheet 13 is flat on the opposite side to the prism portion forming surface. The surface is opposed to the light exit surface 9 of the light guide plate 7, and a space is secured between the light guide plate 7 and the light guide plate 7.

  The second prism sheet 14 has its prism portion forming surface opposed to the prism portion forming surface of the first prism sheet 13, and a plurality of elongated prism portions 13a, 14a of both prism sheets 13, 14. The liquid crystal display panel 1 is arranged in parallel with the first prism sheet 13 with the tops thereof facing each other in the proximity state, and the liquid crystal display panel 1 has its incident surface (the outer surface of the incident-side polarizing plate not shown) as the second. The prism sheet 14 is arranged close to or in contact with the flat surface.

  The first and second prism sheets 13 and 14 refract the light a incident on the light guide plate 7 from the first incident end surface 8a and emitted from the output surface 9 of the light guide plate 7 in a stepwise manner. The peak of the emitted light intensity is in the first direction, that is, the direction inclined at a predetermined angle in the direction of one of the left and right eyes of the display observer with respect to the normal H of the liquid crystal display panel 1. The first illumination light having an existing directivity is emitted, and the light b incident on the light guide plate 7 from the second incident end face 8b and emitted from the output surface 9 of the light guide plate 7 is refracted stepwise. Then, the directivity in which the peak of the emitted light intensity exists in the second direction, that is, the direction inclined at a predetermined angle to the direction of the other eye of the display observer with respect to the normal line H of the liquid crystal display panel 1. It emits as the 2nd illumination light with.

  That is, the light is emitted from the first light emitting element 11a on the right side in the drawing and is incident on the light guide plate 7 from the first incident end face 8a, and the light exit surface 9 of the light guide plate 7 extends to the normal h of the light exit surface 9. On the other hand, the light a emitted in the direction opposite to the first incident end face 8a along the longitudinal direction of the light guide plate is the light guide plate 7 of the first prism sheet 13 as indicated by the arrow in FIGS. The first prism sheet 13 is refracted in a direction in which the angle with respect to the normal h becomes smaller at the interface between the flat surface facing the outside and the outside air (the air layer between the light guide plate 7 and the first prism sheet 13). Is incident on.

  The light a travels toward one side surface of the plurality of elongated prism portions 13a on the opposite surface of the first prism sheet 13, and the side surface and the outside air (the air between the first and second prism sheets 13, 14). The light is refracted in the direction in which the angle with respect to the normal h is further reduced at the interface with the layer) and is emitted from the first prism sheet 13.

  Then, the light a emitted from the first prism sheet 13 is applied to the second prism sheet 14 at one side surface of the plurality of elongated prism portions 14a, that is, from the elongated prism portion 13a of the first prism sheet 13. From the oppositely inclined side surface corresponding to the side surface from which the light is emitted, the light is refracted and incident at the interface between the side surface and the outside air (the air layer between the first and second prism sheets 13 and 14). From the flat surface opposite to the prism sheet 14, the light is refracted at the interface between the flat surface and the outside air, and the normal line h of the light exit surface 9 of the light guide plate 7, that is, the normal line H of the liquid crystal display panel 1, The light is emitted as first illumination light having directivity in which a peak of emitted light intensity exists in a first direction inclined at a predetermined angle in the direction of one of the left and right eyes of the display observer.

  On the other hand, the light is emitted from the second light emitting element 11b on the left side in the drawing and is incident on the light guide plate 7 from the second incident end face 8b. The light exit surface 9 of the light guide plate 7 extends to the normal h of the light exit surface 9. On the other hand, the emission path of the light b emitted in the direction opposite to the second incident end face 8b along the light guide plate longitudinal direction is bilaterally symmetrical with respect to the path of the light a from the first light emitting element 11a. 2 and 3, the light b is emitted from the interface between the flat surface of the first prism sheet 13 and the outside air and the plurality of elongated prism portions 13 a of the first prism sheet 13. The light is refracted in the direction in which the angle with respect to the normal line h becomes smaller at the interface between the other side surface and the outside air, and the interfaces between the other side surface of the plurality of elongated prism portions 14a of the second prism sheet 14 and the outside air and 2 between the flat surface of the prism sheet 14 and the outside air A second direction that is refracted and is inclined at a predetermined angle in the direction of the other eye of the observer with respect to the normal h of the exit surface 9 of the light guide plate 7, that is, the normal H of the liquid crystal display panel 1. Is emitted as the second illumination light having directivity in which the peak of the emitted light intensity exists.

  The surface light source 6 performs display observation in the direction in which the peak of the emitted light intensity of the first illumination light a and the second illumination light b exists according to the display observation distance depending on the use of the liquid crystal display device. It is designed to match the direction toward one and the other of the left and right eyes of the person.

  In this embodiment, as described above, the light a emitted from the first light emitting element 11a is emitted from the light exiting surface 9 of the light guide plate 7, and the light guide plate of the light b emitted from the second light emitting element 11b. The plurality of elongated prisms of the first and second prism sheets 13 and 14 are set such that the exit angle α2 from the exit surface 9 of the light source 7 is an angle range of 50 ° to 80 ° with respect to the normal h of the exit surface 9. By setting the apex angles θ1 and θ2 of the portions 13a and 14a in the range of 70 ° to 100 °, respectively, the light a emitted from the first light emitting element 11a on the right side in the figure is finally converted into the second prism sheet. 14 has a peak of emitted light intensity in the right direction in the figure with respect to the normal line H of the liquid crystal display panel 1, that is, in a direction inclined about 10 ° in the direction of the left eye of the display observer. 5 ° to 10 ° in the left and right direction around the direction Light b emitted from the second light emitting element 11b on the left side in the figure is emitted as first illumination light that spreads at an angle, and finally from the flat surface of the second prism sheet 14, the liquid crystal display panel 1 The emission light intensity has a peak in the left direction in the figure with respect to the normal H, that is, in a direction inclined about 10 ° in the direction of the right eye of the display observer, and the horizontal direction around the peak direction is 5 ° to 5 °. It is made to emit as the 2nd illumination light which spreads at an angle of 10 degrees.

  Hereinafter, the first first light-emitting element 11a on the right side in the figure is referred to as a left-eye light-emitting element, and the second first light-emitting element 11b on the left side in the figure is referred to as a right-eye light-emitting element. The first illumination light a emitted from the second prism sheet 14 and emitted from the second prism sheet 14 in the right direction in the figure (the direction of the left eye of the display observer) with respect to the normal H of the liquid crystal display panel 1 Illumination light, emitted from the right-eye light emitting element 11b, and from the second prism sheet 14 to the normal H of the liquid crystal display panel 1 in the left direction in the figure (the direction of the right eye of the display observer) The emitted second illumination light b is referred to as right-eye illumination light.

  FIG. 5 shows the luminance distribution as viewed from the emission side (liquid crystal display panel 1 side) of the left-eye illumination light a and the right-eye illumination light b emitted from the surface light source 6. Is a right angle with respect to the normal H of the liquid crystal display panel 1 (same as the normal h of the light guide plate), and the negative emission angle is a left angle with respect to the normal H.

  The left-eye illumination light a and the right-eye illumination light b are alternately emitted from the surface light source 6 and incident on the liquid crystal display panel 1, and transmission is controlled by a plurality of pixels of the liquid crystal display panel 1. The light transmitted through these pixels is emitted to the observation side of the liquid crystal display panel 1 and is alternately observed by the left and right eyes of the display observer.

  The surface light source 6 causes most of the light a and b emitted from the emission surface 9 of the light guide plate 7 to have a peak of emitted light intensity in a direction inclined by about 10 ° with respect to the left eye of the display observer. It is emitted as left eye illumination light and right eye illumination light having a peak of emitted light intensity in a direction inclined about 10 ° to the right eye direction, but emitted from the emission surface 9 of the light guide plate 7. A part of the light beams a and b are almost refracted at the interface between the plurality of elongated prism portions 13a and 14a of the first and second prism sheets 13 and 14 and the outside air, as indicated by chain arrows in FIG. Without being transmitted, it is emitted from the flat surface of the second prism sheet 14 as light having a peak of emitted light intensity in an angular direction near 30 ° with respect to the normal H of the liquid crystal display panel 1.

  Therefore, the left-eye illumination light a and the right-eye illumination light b emitted from the surface light source 6 are respectively left of the display observer with respect to the normal H of the liquid crystal display panel 1 as shown in FIG. Light having a certain peak of emitted light intensity in a direction inclined by about 30 ° in the direction opposite to the direction toward the eyes and right eye (direction of about 10 ° with respect to the normal H of the liquid crystal display panel 1). However, since the light emitted from the surface light source 6 in a direction inclined by about 30 ° and transmitted through the liquid crystal display panel 1 is not observed in any of the left and right eyes of the display observer, this light is displayed on the liquid crystal display. The display on panel 1 is not affected.

  Next, the control means 15 for driving the liquid crystal display panel 1 and the surface light source 6 will be described. Although the specific configuration of the control means 15 is not shown, the gate side driver 4 of the liquid crystal display panel 1 and The writing control circuit controls the data-side driver 5 and the illumination control circuit that controls the lighting of the left-eye light-emitting element 11a and the right-eye light-emitting element 11b of the surface light source 6.

  The control means 15 alternately writes left-eye image data and right-eye image data supplied from an external circuit (not shown) to a plurality of pixels of the liquid crystal display panel 1, and the left-eye and right-eye images are written. Among the illumination lights a and b, the illumination light having directivity corresponding to the image data written in the plurality of pixels of the liquid crystal display panel 1 is synchronized with the writing of the image data in the surface light source 6. The light is emitted from.

  The left-eye image data and the right-eye image data are color image data captured by an electronic camera having two left and right imaging lenses arranged at predetermined intervals, for example.

  Further, the control means 15 sets the plurality of pixels of the liquid crystal display panel 1 alternately between the left-eye image data and the right-eye image data for each frame with 1/50 seconds to 1/300 seconds as one frame. At the end of the left-eye image data writing frame, the left-eye light emitting element 11a is turned on after writing the left-eye image data, thereby emitting left-eye illumination light a from the surface light source 6. Then, at the end of the right-eye image data writing frame, the right-eye light emitting element 11b is turned on after waiting for the writing of the right-eye image data, thereby emitting the right-eye illumination light b from the surface light source 6. .

  That is, the liquid crystal display device alternately writes left-eye image data and right-eye image data to a plurality of pixels of the liquid crystal display panel 1 and synchronizes with the left-eye image data and the right-eye image data. By emitting illumination light having directivity corresponding to image data written in a plurality of pixels, the left eye image and the right eye image are alternately displayed with a time difference, and a stereoscopic image is displayed to the display observer. Is to be observed.

  According to this liquid crystal display device, the left-eye image and the right-eye image are alternately displayed with a time difference, so that both the left-eye image and the right-eye image are displayed on all the pixels of the liquid crystal display panel 1 respectively. It can be used and displayed, and a high-resolution stereoscopic image can be displayed.

  Moreover, in this liquid crystal display device, the surface light source 6 is determined in advance in the direction of one of the left and right eyes of the display observer with respect to the normal H of the liquid crystal display panel 1, for example, the direction of the left eye. The first illumination light (left-eye illumination light) a having directivity in which the peak of the emitted light intensity exists in the first direction inclined at an angle and the other of the observer with respect to the normal H Alternating with second illumination light (right eye illumination light) b having directivity in which the peak of the emitted light intensity exists in a second direction inclined at a predetermined angle in the direction of the eye, for example, the right eye In addition, it suffices if it emits toward the entire display area A in which a plurality of pixels of the liquid crystal display panel 1 are arranged. Therefore, the liquid crystal display device can be easily manufactured.

  In the liquid crystal display device of the above embodiment, the surface light source 6 is made of a plate-shaped transparent member, and is formed on the opposing end surfaces of the transparent member so that light is incident thereon. A light guide plate 7 having end faces 8a and 8b, and an exit face for emitting light incident from the first and second entrance end faces 8a and 8b and guided in the transparent member in different directions; The first and second light emitting elements 11a and 11b that are arranged to face the first and second incident end faces 8a and 8b of the light plate 7 and are alternately lit, and on the light exit surface 9 side of the light guide plate 7, respectively. The light a entering the light guide plate 7 from the first and second incident end faces 8a and refracting the light a emitted from the exit face 9 has a peak of the emitted light intensity in the first direction. The first illumination light having directivity is emitted, and the light guide plate 7 Light refracting means 12 that refracts the light b incident from the incident end face 8b and radiated from the exit face 9 and emits the second illumination light having directivity in which the peak of the emitted light intensity exists in the second direction. Therefore, a first angle inclined from the surface light source 6 with respect to the normal H of the liquid crystal display panel 1 by a predetermined angle in the direction of one of the left and right eyes of the display observer. The first illumination light a having directivity in which the peak of the emitted light intensity exists in the direction of the second and the second illumination light inclined at a predetermined angle with respect to the normal H to the direction of the other eye of the observer. The second illumination light b having directivity in which the peak of the emitted light intensity exists in the direction can be emitted toward the liquid crystal display panel 1.

  Furthermore, in the said Example, the said light refracting means 12 is arrange | positioned facing the output surface 9 of the said light-guide plate 7, 1st and 2nd entrance-end surface 8a, 8b of the said light-guide plate 7 is provided on one surface. A first prism sheet 13 in which a plurality of parallel elongated prism portions 13a are formed, and the first prism sheet 13 is disposed on the opposite side of the light guide plate 7 side of the first prism sheet 13, and the first prism sheet is provided on one surface. 13 and the second prism sheet 14 formed with a plurality of elongated prism portions 14a parallel to the elongated prism portion 13a, the light incident on the light guide plate 7 from the first incident end face 8a. The light a emitted from the emission surface 9 and the light b incident from the second incident end face 8b and emitted from the emission surface 9 are refracted stepwise by the first and second prism sheets 13 and 14, respectively. Let the first The first illumination light having directivity in which the peak of the emitted light intensity exists in the direction and the second illumination light having directivity in which the peak of the emitted light intensity exists in the second direction are emitted. be able to.

  In the above embodiment, the first and second prism sheets 13 and 14 constituting the light refracting means 12 of the surface light source 6 are arranged with their respective prism portion forming surfaces facing each other. The first and second prism sheets 13 and 14 may be arranged such that the flat surfaces opposite to the respective prism portion forming surfaces are opposed to each other, or the prism portion forming surface of one prism sheet and the other prism sheet. These flat surfaces may be arranged to face each other.

  The light refracting means 12 of the surface light source 6 is not limited to the first and second prism sheets 13 and 14, but is incident on the light guide plate 7 from the first and second incident end faces 8a and is emitted. The light emitted from the surface 9 is refracted and emitted as first illumination light having directivity in which the peak of the emitted light intensity exists in the first direction, and enters the light guide plate 7 from the other incident end face 8b. If the light emitted from the light exit surface 9 is refracted and is emitted as the second illumination light having directivity in which the peak of the emitted light intensity exists in the second direction, it is constituted by another optical member. May be.

  In addition, the liquid crystal display device of the present invention can display not only a stereoscopic image but also a planar image. In that case, both the first and second illumination lights are always emitted from the surface light source 6. The plane image data is written to a plurality of pixels of the liquid crystal display panel 1 every frame, or the plane image data is written to a plurality of pixels of the liquid crystal display panel 1 every frame, and at the end of each frame, the plane image data is written. What is necessary is just to emit both the 1st and 2nd illumination light from the said surface light source 6 waiting for writing of plane image data.

1 is an exploded perspective view of a liquid crystal display device showing an embodiment of the present invention. The side view of the said liquid crystal display device. The enlarged side view of a part of surface light source of the said liquid crystal display device. FIG. 3 is a luminance distribution diagram of light incident on a light guide plate of the surface light source from a first incident end surface and emitted from an output surface, and light incident on the light guide plate from a second incident end surface and emitted from the output surface. The luminance distribution figure of the 1st and 2nd illumination light radiate | emitted from the said surface light source.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display panel, A ... Display area, 6 ... Surface light source, 7 ... Light guide plate, 8a, 8b ... Incidence end surface, 9 ... Output surface, 11a. 11b ... light emitting element, 12 ... light refracting means, 13, 14 ... prism sheet, 13a, 14a ... elongated prism section, 15 ... control means.

Claims (8)

A liquid crystal display panel having a plurality of pixels and alternately displaying a left-eye image and a right-eye image on each pixel in a time-division manner;
The first illumination light is present peak of the emitted light intensity in a first direction the inclined first predetermined angle from the normal of the liquid crystal display panel in a predetermined direction, wherein the normal of the liquid crystal display panel The left-eye image and the right-eye image alternately displayed are the second illumination light in which the peak of the emitted light intensity exists in the second direction inclined at the second predetermined angle to the side different from the predetermined direction side. A surface light source that emits toward the liquid crystal display panel alternately in a time-sharing manner in synchronization with display switching timing with an image;
A stereoscopic image display device comprising:
The surface light source is
A light guide plate disposed to face the liquid crystal display panel;
A first light emitting element that makes light incident on the light guide plate from the first end surface of the light guide plate;
A second light emitting element that makes light incident on the light guide plate from a second end face opposed to the first end face;
A pair of single-sided prism sheets disposed between the light guide plate and the liquid crystal display panel, and having a plurality of elongated prisms extending in a direction parallel to the first end surface and the second end surface on one surface. When,
Have
In the pair of single-sided prism sheets, the elongated prisms are arranged at equal intervals between the pair of single-sided prism sheets, and the vertical angles of the corresponding elongated prisms coincide with each other on the normal line. A stereoscopic image display device characterized by being arranged in   The stereoscopic image display device according to claim 1, wherein the pair of single-sided prism sheets are arranged such that surfaces on which the elongated prisms are formed face each other. Wherein the first illumination light, so that the peak of the emitted light intensity is inclined the first predetermined angle from the normal to the side of the first light-emitting elements are arranged in the liquid crystal display panel, the first The light from the light emitting element is light distributed by the light guide plate and the pair of single-sided prism sheets,
The second illumination light includes the second illumination light such that the peak of the emitted light intensity is inclined from the normal line of the liquid crystal display panel to the side where the second light emitting element is disposed at the second predetermined angle. 3. The stereoscopic image display device according to claim 1, wherein light from the light emitting element is light distributed by the light guide plate and the pair of single-sided prism sheets. When the light from the first light emitting element is emitted from the single-sided prism sheet adjacent to the light guide plate of the pair of single-sided prism sheets, the peak of the emitted light intensity is from the normal line of the liquid crystal display panel. In a direction inclined to the side where the second light emitting element is disposed,
When the light from the second light emitting element is emitted from the single-sided prism sheet adjacent to the light guide plate of the pair of single-sided prism sheets, the peak of the emitted light intensity is from the normal line of the liquid crystal display panel. The stereoscopic image display apparatus according to claim 3, wherein the stereoscopic image display apparatus is in a direction inclined to the side where the first light emitting element is disposed.   5. The stereoscopic image display device according to claim 1, wherein each of the pair of single-sided prism sheets has an apex angle set in a range of 70 ° to 100 °.   6. The stereoscopic image display device according to claim 1, wherein in each of the pair of single-sided prism sheets, an arrangement interval of the elongated prisms is equal to an arrangement interval of pixels. Have a plurality of pixels, the liquid crystal display panel for displaying the divided alternately when a left eye image and a right eye image,
The first illumination light is present peak of the emitted light intensity in a first direction the inclined first predetermined angle from the normal of the liquid crystal display panel in a predetermined direction, wherein the normal of the liquid crystal display panel Second illumination light having a peak of emitted light intensity in a second direction inclined at a second predetermined angle to a side different from the predetermined direction side is alternately directed to the liquid crystal display panel in a time-division manner. A surface light source that emits
With
A stereoscopic image display device that synchronizes the emission switching timing of the first illumination light and the second illumination light and the display switching timing of the left-eye image and the right-eye image ,
The surface light source is
A light guide plate disposed to face the liquid crystal display panel;
A first light emitting element that makes light incident on the light guide plate from the first end surface of the light guide plate;
A second light emitting element that makes light incident on the light guide plate from a second end face opposed to the first end face;
A pair of single-sided prism sheets disposed between the light guide plate and the liquid crystal display panel, and having a plurality of elongated prisms extending in a direction parallel to the first end surface and the second end surface on one surface. When,
Have
In the pair of single-sided prism sheets, the elongated prisms are arranged at equal intervals between the pair of single-sided prism sheets, and the vertical angles of the corresponding elongated prisms coincide with each other on the normal line. A stereoscopic image display device characterized by being arranged in The stereoscopic image display device according to claim 1, wherein the first predetermined angle is equal to the second predetermined angle.

Images