TW201227093A - Surface source device and 3d display - Google Patents

Abstract

The present invention is to reduce, in a surface source device used in a 3D display, visual differences of intensities (differences of light and dark) between right and left eyes and screen visual differences of luminous intensities (non-uniformity). According to the present invention, a left light source 23a and a right light source 23b are respectively arranged to face incident surface of a light guiding plate 22. An emitting pattern 25a for emitting, from light emitting face 26, light generated by the left light source 23a and an emitting pattern 25b for emitting, from light emitting face 26, light generated by the right light source 23b are formed on the back face of the light guiding plate 22. If a peak intensity of light emitted from the terminal of the lighting region at the left light source 23a (right light source 23b) side is Ia1 (Ia2) when left light source 23a is turned on and a peak intensity of light emitted from the terminal of the lighting region at the left light source 23a (right light source 23b) side is Ib1 (Ib2) when right light source 23b is turned on, them it would be Ia1 > Ib1 (Ia2 < Ib2).

Description

201227093, invention description: TECHNICAL FIELD The present invention relates to a surface light source device and a stereoscopic display device. Specifically, it relates to a stereoscopic display device for three-dimensionally displaying an image or a video, and a surface light source device for the stereoscopic display device. [Prior Art] A stereoscopic display device for displaying a so-called three-dimensional image has a method of using observation glasses and a method of not using glasses. However, in the method of using glasses, the observer must wear the glasses on the head, so that it is not only troublesome but also gives the observer an uncomfortable feeling. Therefore, it is more popular as a stereoscopic display device to use no glasses. The brothers 1 (A) and 1 (B) are schematic views showing the principle of a stereoscopic display device that does not use glasses. In the stereoscopic display device 1 1, a left side light source is disposed opposite to the left entrance light entrance end of the blood-guide plate 12, and a magic light source m is disposed opposite to the right human light end surface of the light guide plate 12. Although not shown in the back surface or the front surface (surface 16) of the light guide plate 12, a plurality of light emitted from the left side light source is emitted from the light guide plate 12, and the light is emitted from the light guide plate 12 The micro-emission pattern and the light emitted from the right-side light source 13b are guided from the π-print to the light-guide plate 12, and the plurality of micro-emissions emitted from the H-light exit surface 16 are disposed on the front surface of the light guide plate 12. The cymbal 14 is disposed on the front side of the cymbal 14 with a liquid crystal panel, and the left and right sides are attached to the left and right of the observer's position of the present device as long as there is no special constraint.胄 胄 stereoscopic display - 4 - 201227093 In addition, the liquid crystal panel 15 displays the right-eye image and the left-eye image alternately in a time-sharing manner, and the right-side light source 1 3 b is illuminated in synchronization with the right-eye image (this) At this time, the left light source 13a is turned off.) The left light source 13a emits light in synchronization with the image for the left eye (in this case, the right light source 丨3b is turned off). When the right side light source 丨3b emits light as shown in Fig. 1(A), the light Lb' entering the right side light source 13b in the light guide plate 12 is totally reflected by the emission pattern on the back surface, and is emitted from the light exit surface 16 The lens 14 is condensed and concentrated in the direction of the right eye 17b. Thereby, the light emitted from the light exit surface i 6

Lb is converted into the image for the right eye by the liquid crystal panel 15, and is incident on the right eye 17b of the observer. Similarly, as shown in Fig. 1(B), when the left side light source 13a emits light, the light La entering the left side light source 13a in the light guide plate I2 is totally reflected by the emission pattern on the back surface, and is emitted from the light exit surface 16, and is borrowed. The sepals (4) are concentrated in the direction of the left eye 17a after being shot. Thereby, the light La ′ emitted from the light exit surface 16 is converted into the image for the left eye by the liquid crystal panel 15 and enters the left eye 17a of the observer. As a result, the observer recognizes the image for the right eye and the image for the left eye with the right eye 17b and the left eye 17a, respectively, and recognizes it as a stereoscopic image by the observer. Further, as such a stereoscopic display device, for example, it is disclosed in the patent document. In the above-described three-dimensional display skirting, the method of eliminating the unevenness of the light exiting surface 而 and averaging the in-plane frontal intensity is performed. An emission pattern for emitting light from the right side light source 13b, a straight line T of the =2(4) map. In the entire light-emitting region, the distribution of the light-emitting intensity is uniform, and therefore, the distribution is defined in such a manner that the pattern density increases as the right-side light source 13b is far away. Specifically, -5- pattern density refers to the unit; # &amp; ^ + The area of the back surface of the board containing the pattern of the shot pattern contained in the flat area is called _ total value. In addition, in the light region in Fig. 2, the right side of the light region, the end of the source side, and the left end point to the side of the left side of the light source - i mountain / ·, γ (the same applies hereinafter). With regard to such a source, the pattern density of the emission pattern is increased, so that the surface light of $degreeit &lt;the point of self-conformation is described in, for example, the patent prior art 201227093 '' for the source from the right side, &quot;b The light emitted by the light is determined according to the distribution curve Gb of the second (8) diagram. The pattern is used to emit the light from the left light source 13 3a and the straight line TG ′ of the image of FIG. 2( 4 ) is emitted. In view of this, the distribution is defined by the way that the light source 13a is increased by μ, and the round tea is increased. The knuckle curve ～ of the emission pattern 2(B) from which the light from the left light source 13a is emitted is determined to be _(four) degrees. Japanese Patent Laid-Open No. Hei. No. 4,045, 464, the disclosure of which is hereby incorporated by reference. On the 'high visual sensitivity', the visual sensitivity decreases as the direction of the line of sight deviates. Therefore, when viewing the phase on the screen with the left eye and the right eye, even if the illumination intensity of the left-eye image at this position is the same as the illumination intensity, the pattern is displayed in the left eye and the right eye. Similarly, if the first intensity is substantially equal to the left side, the projection is based on the projection of the first exit pattern in the light-emitting region at the right end of the light guide. When you look at the direction, you will be in a hurry. When you are in the same position, the image for the right eye is not the same as 201227093, so there will be a physiological difference between the left eye and the right eye. Moreover, the degree of the difference between the brightness and the darkness varies from 9 to 10 degrees. As a result, the visibility of the image for the left eye and the discrimination of the image for the right eye are different, resulting in insufficient stereoscopic effect or brightness on the face. Here, the reason will be explained with reference to the third (A) drawing. Fig. 3(a) shows the liquid crystal panel, that is, the surface light source device. In the case of a stereoscopic display device, the position of the eye is fixed and the screen is observed. Therefore, the direction of the line of sight CL of the observer's left eye 17a (the direction of the line of sight is indicated by a two-dot chain line) and the right eye 17b. The direction of the line of sight CR is fixed toward the center of the cymbal 14. Now, the light Lb emitted from the point p located in the right region of the light-emitting region and incident on the right eye 7b, and the light La emitted from the same point P and incident on the left eye 17a are considered. The direction of the line of sight CR of the right eye 17b and the direction of the line of sight cl of the left eye 17a are inclined in the opposite direction. Therefore, when the angle formed by the light Lb entering the right eye 17b and the line of sight CR is set to 0, it will enter the left. When the angle formed by the light of the eye i7a and the line of sight CL is set to be, the relationship of # &gt; is obtained. Thus, the deviation of the light Lb from the direction of the line of sight is larger than the deviation of the light La. Therefore, even if the luminous intensity of the light Lb and the light La are equal, the apparent luminous intensity perceived by the observer visually is also light. Lb is smaller than light La (i.e., the perceived light Lb is darker). Further, when the light Lb and the light La emitted from the point located on the left side region of the light-emitting region are considered, the state is opposite to that of the third (A) diagram. Therefore, even if the light intensity of the light Lb and the light La is equal ' The apparent luminous intensity perceived by the observer visually will also be that the light Lb is larger than the light La (i.e., the perceived light Lb is brighter). 201227093 Therefore, in the well-known surface light source device, as shown in the second (A) diagram, even if the light-emitting intensity of the light-emitting region is averaged, the left-eye image is compared with the right-eye image in the right region. Recognized to be brighter, the image for the right eye is still recognized as brighter than the image for the left eye in the left region. Therefore, when used in a stereoscopic display device, the balance between the image for the right eye and the image for the left eye is doubled, resulting in a decrease in stereoscopic effect. As shown in the third figure (A), the light Lb entering the right eye 17b and entering the left eye na are emitted from the point p of the distance χ measured from the right end of the light guide plate 12 (one end of the right side light source 13b side). The light "considered, and Jb, Ja, respectively, not the light Lb, the apparent luminous intensity of La, and these light Lb, La are felt by the observer's vision taking into account the observer's visual sensitivity. Light. The curve Sg of Fig. 3(B) finds the apparent luminous intensity ratio Jb/Ja at a point p from the right end at a distance X. However, the apparent luminous intensity ratio is performed. In the calculation, the optical luminous intensity of the light Lb and the light La is set to be equal. Thus, even if the surface light source device is designed in such a manner that the optical luminous intensity of the light Lb and the light La are equal, the observer perceives the apparent appearance. The luminous intensity ratio Jb/Ja will still vary greatly as shown in Fig. 3(B), making it difficult to be regarded as a stereoscopic image.

Further, when the eye image for the left eye is observed with the left eye (or the eye image for the right eye is observed with the right eye), a difference in brightness between the left side region and the right side region of the light-emitting region is caused by the visual sensitivity factor. Here, the reason will be explained in the fourth drawing. Now, when the light emitted from the point P2 of the right area and entering the right eye 17b is set to Lb2, the light emitted from the point p1 of the left area and entering the right eye 17b is set to Lb1, then the light Lb2 and line of sight CR 201227093 The area is darker and the left side area is brighter, so that the left and right brightness balance is destroyed, resulting in uneven brightness. Especially on the right end, the picture becomes extremely dark. For the same reason, the image for the left eye is made larger in angle (j)b2 than the light Lbl in the left region. Therefore, even if the light Lb2 is light or the like, the luminous intensity Jb 1 on the apparent light emission of the light Lb2 is small. Therefore, the angle formed by the line of sight CR (the optical intensity of the jjbl Lbl, the intensity Jb2 is still better than the apparent view of the light Lb 1) causes the image for the right eye to be dark on the right side and brighter on the right side, so that the left and right brightness The balance is damaged and the redundancy is uneven, especially at the left end. The screen is extremely dark. The present invention has been developed in view of the above technical problems, and the object thereof is to reduce the surface light source device used in the stereoscopic display device. Apparent intensity difference (shading difference) between the small right eye and the left eye. In addition, another object of the present invention is to reduce the apparent appearance on the screen in the surface light source device used in the stereoscopic display device. The light-emitting intensity difference (inhomogeneous brightness, etc.). [Means for Solving the Problem] The first-surface light source device of the present invention includes a light guide plate that guides an incident end face of a pair of opposite light incidents. The light is emitted from the light exit surface; the first light source is configured to inject light from one of the light incident end faces toward the light guide plate; and the second light source causes the light to enter the light Among the end faces a light incident end face is incident on the light guide plate; and the cymbal sheet is disposed to face the light emitting surface of the light guide plate; the first surface light source device is characterized in that the first light is to be illuminated The peak intensity of the light emitted from the end portion on the first light source side in the light-emitting region at the time of the light source is Ial, and the light emitted from the end portion on the first light source side of the light-emitting region when the second light source is turned on Peak intensity -9 - .201227093 b 1 ; In the peak intensity device that illuminates when the end of the front source side emits a light source, the brightness of the point and the second difference of the lighting become smaller, so the difference between the brightness and the light is entered. The method includes a light source that emits light from the light exit surface and emits light from the light guide plate, and that emits light from the front plate; and a light source device that overlaps the light guide plate of the first light guide plate from the light guide surface from the first The light is emitted from the end portion, and the intensity of the light-emitting region when the end portion of the light-emitting end is set to Ib1 is Ia2, and the second light source side is Ia2 &lt; Ib2 in the image of the present invention. Apparently at the end of the end of the end The identification of the right-eye image of the surface of the present invention is a guiding injection plate, which is a guiding light source, such that a light-injecting plate is incident on the light-injecting end surface such that the first light guiding end surface is located a bit arrangement in the light plate; when the peak light region of the light emitted by the first light source is set to lb 1 from the front, the light-emitting region

Ial &gt; I from the second light that illuminates the first end of the first end of the light emitted by the first surface light source, and the light intensity of the second surface light source is perceived by the left eye The light that is incident on the light is used to set the intensity of the light from the first and second light sources, the second light guide plate and the front side, and the light-emitting area of the second surface light that is adjacent to the front side. I a 1, the first light source side is Ial &gt; Ibl. When the second light source is the first light source, the peak light region of the light is set to Ib2, and the image of the light source at the first light source can be reduced. Small viewing can improve stereoscopicity: the first light guide plate is 'out; the second light guiding surface is emitted; the first end surface faces the second light guide plate lens; wherein, the second and the second guide are facing each other The method is: the peak intensity of the light when the front side of the source side is illuminated by the two light sources, and the peak intensity of the light of the first light source is -10. The 201227093 degree is set to Ia2, and the second light source is turned on. Shooting from the end of the second light source side When the peak intensity of the emitted light is set to Ib2, it becomes Ia2 &lt; Ib2. In the second surface light source device of the present invention, the difference between the apparent luminous intensity of the image end when the first light source is illuminated and the apparent luminous intensity of the image end when the second light source is illuminated It becomes smaller. Therefore, the difference between the right eye and the left eye when viewing the face can be reduced, and the visibility of the stereo image can be improved. In an embodiment of the first or second surface light source device of the present invention, the peak intensity of the light 2 emitted from the arbitrary light-emitting point when the light-emitting region is illuminated by the first light source is set to la, and the light of the peak intensity Ia is relatively The angle formed by the normal line of the light-emitting point in the vertical direction is the peak intensity of the light emitted from the same light-emitting point in the light-emitting region when the first light source is turned on. Further, in the case of ib, when the angle formed by the light of the peak intensity Ib with respect to the normal to the vertical light-emitting point is eb, the case of l〇a|&lt;|0b||ea|&gt;|0b| According to the foregoing embodiment, the difference between the illuminance intensity and the illuminating degree becomes small, so that the difference between the brightness and the sensation perceived by the eye is, in the foregoing embodiment, Ia, Ib is preferably 'to become I a &gt; I b ; ' It becomes Ia&lt;Ibe' the apparent illuminating intensity of the image when the image is illuminated by the first light source, and the apparent illuminance of the image can be reduced by almost reducing the right eye and the left side of the image. Identification. Further, the angles 0a, 0b and the peak intensity I I &lt; the case of the ’ 丨 成为 become 1 _0 &lt; Ia / Ib &lt;3.5; I 丨 丨 , , , 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 201227093 In the first or second surface light source device of the present invention, the peak intensity of the light emitted from the end portion of the first "" is set in the light-emitting region when the first light source is turned on. In the case of Ial, when the light source side of the light source is on the side of the light source, the peak intensity of the light emitted from the second light source side of the light-emitting area is set to Ia2, and Ial &gt; The stop of Ia2. The peak intensity of the light emitted from the end portion of the first source side of the light-emitting region when the second light source is turned on is Ib2, and the light-emitting area when the light source is turned on before the light source is turned on When the peak intensity of the light emitted from the end portion on the first light source side is lb 1 , the condition of Ib2 &gt; Ib i is satisfied. According to the foregoing embodiment, the difference in apparent luminous intensity at both end portions of the image when the first light source is illuminated can be reduced. In addition, the difference in apparent luminous intensity at both end portions of the image when the second light source is turned on can be reduced. Thereby, the unevenness of the brightness of the image can be reduced, and the image can be easily viewed. Further, in this embodiment, the peak intensity Ia 丨, Ia2 satisfies the condition of 10 &lt; Ial / Ia2 &lt;3.5; and the peak intensity Ib1, Ib2 satisfies the condition of 1 · 〇 &lt; Ib2 / Ibl &lt; 3.5. In another embodiment of the first surface light source device of the present invention, the light exiting surface of the light guide plate or the surface facing the light is formed to form light for injecting light from the first light source from the foregoing a first emission pattern emitted from the light exit surface and a second emission pattern for emitting light incident from the second light source from the light exit surface. In this embodiment, by adjusting the distribution of each of the emission patterns, the apparent luminous intensity (ratio) when the first light source is illuminated or the apparent luminous intensity when the second light source is illuminated (ratio) ) becomes the desired feature. 201227093 In another embodiment of the second surface light source device of the present invention, the light exiting surface of the first light guide plate or the surface facing the light emitting surface forms light for injecting light from the first light source a first emission pattern emitted from a light exit surface of the first light guide plate is formed on a light exit surface of the second light guide plate or a surface facing the light, so as to be incident from the second light source a second emission pattern that is emitted from the light exit surface of the second light guide plate. In this embodiment, by adjusting the distribution of each of the emission patterns, the apparent luminous intensity (ratio) when the first light source is illuminated or the apparent luminous intensity (ratio) when the second light source is illuminated can be made. Become the desired feature. In the above embodiment of the first or second surface light source device, the first emission pattern system may be configured to increase the pattern density in a nonlinear function manner away from the first light source, away from the first light source. The increase rate of the aforementioned pattern density in the direction is constant, and the increasing rate is gradually increased as moving away from the first light source, and the second emission pattern is configured such that the pattern density is a nonlinear function as moving away from the second light source. The manner is increased, the rate of increase of the pattern density in the direction away from the second light source is constant, and the increasing rate is gradually increased as moving away from the second light source. Further, the first emission pattern may be in a region farther from the first light source than the center of the light-emitting region, and the increase rate of the pattern density of the first emission pattern in a direction away from the first light source is assumed to be uniform The distribution of the pattern density of the first emission pattern in which the light of the emission intensity is emitted from the light exit surface is smaller, and the second emission pattern may be in a region farther from the second light source than the center of the light-emitting region - 13-201227093 The more detailed source of the source is more dense, and the increase rate of the density of the second emission pattern in the direction of the distance from the second light source is higher than that of the assumption The distribution of the pattern of the second emission pattern in which the light of uniform luminous intensity is emitted from the front light exit surface is smaller. Further, the first emission pattern may be in a region farther from the first light source than the center of the light-emitting region, and the increase rate of the pattern density of the first emission pattern in the direction away from the first light source is constant, and the two-eject pattern is It is also preferable that the increase rate of the pattern density of the second shot pattern in the direction away from the second light source is constant in a region farther away from the second light than the center of the light-emitting region. In addition, in the example of the first or second surface light source device of the present invention, the first emission pattern may be in a region closer to the first light source than the center of the light-emitting region, and the pattern of the first emission pattern is dense. As the distance from the first light source is reduced, the pattern of the first shot pattern is increased along with the distance from the first light source in a region away from the first light source in the center of the light emitting region. The second shot pattern may be In a region closer to the second light source than the center of the light-emitting region, the pattern density of the second emission pattern decreases as it is away from the second light source, and is farther away from the second light source than the center of the light-emitting region, so that the foregoing The pattern density of the two shot patterns increases as it moves away from the aforementioned second source. V〇|yj 'the thickness of the first light guide plate is gradually thinned from the front end of the light source end face opposite to the light incident end face of the first light source, and the second light guide plate is The thickness is from the opposite of the first 31: light source into the -14-201227093 light end face. According to the above-mentioned one light source, it is assumed that the thickness of the light can be a thicker case of the specific strength and can be changed to a thick part. The end surface facing the opposite side of the light incident end face is gradually thinned as the light end face is farther from the front and gradually merges toward the tapered end portion. In the root embodiment, by adjusting the thickness of each of the light guide plates, the apparent luminous intensity (ratio) at the time of lighting or the luminous intensity (ratio) at the time of lighting the second light source can be made into a desired characteristic. The light exit surface of the first light guide plate is emitted to change, and the light exit surface of the second light plate changes gently. In addition, as for the thickness of the light plate, the first source device closer to the first light source from the first light source plate may be further oriented from the end of the end opposite to the first surface. The thickness of the light plate is the end of the side of the light source which is one of the light incident end faces. In addition, the ratio of the thickness in the light guide plate is increased. In the foregoing embodiment, the degree of change from the light guide plate is more gently assumed to be a change from the thickness of the light guide and a decrease in the thickness of the second guide. The reduction rate of the above-mentioned degree of implementation is small as the second second guide is closer to the second surface of the second invention, and the thickness of the first light guide plate is thicker toward the side of the first light source. The light-incident end surface of the second light-emitting surface is gradually thicker than the first end surface, and the second thickness may also be a thickness of the light guide plate having a uniform light-emitting intensity according to a certain thickness, and the first light is emitted. The light guides are reduced according to a certain ratio of the thickness of the light guide plate and the end of the light source to the thickness reduction rate. In an embodiment, a light source may be gradually thinned toward the entrance surface, and an end surface of the end portion from the end surface opposite to the second light may be gradually formed in the foregoing gradually increasing region from the end surface toward the foregoing embodiment. -15-201227093 A stereoscopic display device according to the present invention is characterized in that an optical Dinghan Hanxin crystal panel is disposed in front of the first or second surface light source device of the present invention. In the above-described stereoscopic display device, the apparent luminous intensity can be simplified, so that the quality of the stereoscopic image can be improved. Further, the means for solving the above-described problems of the present invention has a feature in which the constituent elements described above are appropriately combined, and the present invention can be variously changed in accordance with the combination of the above-described constituent elements. [Embodiment] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments described below, and various modifications and changes can be made without departing from the spirit and scope of the invention. [First Embodiment j (surface light source device) Hereinafter, the surface light source device 21 of the first embodiment will be described with reference to Fig. 5'. In the surface light source device 21, one or a plurality of left side light sources 23a are disposed opposite to the left entrance light incident end surface of the flat light guide plate 22, and/or the right side light incident end faces of the light guide plate 22 are opposed to each other. Ground configuration - one or a plurality of right side light sources 2 3 b. The light guide plate 2 2 is formed into a flat plate shape by a high refractive index translucent resin such as polycarbonate resin or polydecyl methacrylate resin. Both the left side light source 23a and the right side light source 23b are composed of an LED light source that emits white light. The left light source 23a has its light exit window disposed opposite to the left entrance light incident end surface of the light guide plate 22. Similarly, the right side light source 23b is disposed such that its light exit window is opposed to the right entrance light incident end surface of the light guide plate 22. The left side light source 23a and the right side light source 23b are controlled so as to be alternately turned on or off in a certain period of time -16 - 201227093. Further, as the left side light source 23a and the right side light source 23b, a cold cathode ray tube can be used instead of the LED light source. A plurality of minute emission patterns 25a for emitting light from the left side light source 23a and entering the light guide plate 22 from the front surface (light exit surface 26) of the light guide plate 22 are formed on the back surface of the light guide plate 22, and The plurality of minute emission patterns 25b that are emitted from the right light source 23b and enter the light guide plate 22 are emitted from the light exit surface 26 of the light guide plate 22. The emission patterns 25 &amp; and the emission patterns 25b are formed on the back surface of the light guide plate 22 so as to have a substantially uniform pattern density distribution. A reflector 28 is disposed on the back surface of the light guide plate 22. The reflector 28 is formed of a highly reflective material such as a white resin sheet or a metal foil, and is used to reflect light leaking from the back surface of the light guide plate 22 and then incident on the light guide plate 22, which can reduce light leakage. Improve light utilization efficiency. Further, an optical sheet 24 is disposed on the front surface of the light plate 22. The optical sheet 24 concentrates the light for generating the image for the left eye emitted from the light exit surface 26 of the light guide plate 22 toward the left eye 27a of the observer, and emits the light from the light exit surface 26 to generate the right. The light of the ophthalmic image is concentrated toward the observer's right eye 27b. Fig. 6(A) is a schematic view showing only the emission pattern 25b for reflecting the light Lb from the right light source 23b among the emission patterns 25a and 25b. Further, Fig. 6(B) is a schematic view showing only the emission pattern 25a for reflecting the light La from the left side light source 23a, and the emission pattern 25b is increased in pattern density as it goes away from the right side light source 23b. The way it is formed. The emission pattern 25a is formed so as to increase the pattern density as it goes away from the left side 201227093 light source 23a. Further, the respective lights Lb and La emitted from the light sources 23b and 23a are guided by the light guide plate 22 while being totally reflected between the front surface and the back surface of the light guide plate 22, and the light Lb is totally reflected by the emission pattern 25b. Thereafter, the light is emitted from the light exit surface 26, and the light La is totally reflected by the emission pattern 25a, and is emitted from the light exit surface 26. The above-described emission patterns 2 5 a, 2 5b can be formed into various shapes. Figures 7 through 0 show several of these shapes. The emission pattern 2 5a, 2 5b can be formed as a concave pattern in which the back surface of the light guide plate 22 is partially recessed, or a convex pattern in which the back surface of the light guide plate 22 is partially protruded. Only the concave pattern is shown here. Figs. 7(B) and 7(C) are a perspective view and a cross-sectional view showing the triangular-shaped emission patterns 25a and 25b, and the seventh (A) is a concave pattern of the emission patterns 25a and 25b. Rear view of the light guide plate 22. In the emission patterns 25a and 25b, the light Lb and La are totally reflected so that the planar slopes toward the respective light sources 23a and 23b are formed, and the emission patterns 25a and the emission patterns 25b face each other. The opposite direction is disposed below the light guide plate 22. Figs. 8(B) and 8(C) are perspective views and a plan view showing the triangular pyramid-shaped emission patterns 25a and 25b. The eighth (A) diagram shows that the emission patterns 25a and 25b are recessed on the back surface. Rear view of the light guide plate 22. In the emission patterns 25a and 25b, the light Lb and the light are formed to be totally reflected by the two inclined surfaces on the side of the light sources 23a and 23b. Therefore, the light Lb can be made in the width direction of the light guide plate 22. La diffusion. Figs. 9(B) and 9(C) are a perspective view and a cross-sectional view showing the quadrangular pyramid-shaped emission patterns 25a, 25b, and Fig. 9(A) shows the emission pattern 201227093 25a, 25b recessed on the back side. Rear view of the light panel 22. In this case, the emission patterns 25a and 25b are formed so that the light Lb and La are totally reflected toward the two inclined surfaces on the respective light sources 23a and 23b. Therefore, the light Lb can be made in the width direction of the light guide plate 22. La diffusion. 10(B) and 1(C) are perspective views and cross-sectional views showing the spherical emission patterns 25a, 25b. The first (A) diagram shows the emission patterns 25a, 25b recessed on the back surface. Rear view of the light panel 22. The points in the ι〇(Α), 10(B), and 10(C) diagrams show the vertex positions of the emission patterns 25a to 25b. The emission patterns 25a and 25b are formed in the direction of the light incident end faces of the vertical light guide plates 22. a longer elliptical shape in which the vertex position of the exit pattern 2 5 a is deviated away from the left side light source 2 3 a , and in the exit pattern 2 5 b , the vertex position is away from the right side light source. The direction of 23b deviates. Here, the emission patterns 25a and 25b are provided on the back surface of the light guide plate 22 so that the light guided in the light guide plate 22 is totally reflected toward the light exit surface 26 and the light is emitted from the light exit surface 26. Although the injection pattern may be provided on the front surface of the light guide plate (light exit surface 26) (the same applies to other embodiments). When the emission pattern is provided on the front surface of the light guide plate, the light incident on the emission pattern provided on the front surface of the light guide plate passes through the front surface (emission pattern) of the light guide plate and is emitted forward from the light exit surface 26. Fig. 11 is a detailed view showing the shape of the optical sheet 24. On the back surface of the optical sheet 24, a group 24a' in which fine triangular ridges are arranged is formed, and a lens group 24b in which fine cylindrical lenses are arranged is formed on the front surface. The 稜鏡 group 24a and the lens group 24b have a uniform cross-sectional shape perpendicular to the width direction of the light guide plate 22, and are arranged at a certain pitch along the length direction of the 201227093 of the light guide plate 22. However, the arrangement pitch p 2 of the lens group 24b is slightly larger than the arrangement pitch p 1 of the 稜鏡 group 24a. The 稜鏡 group 24a is disposed symmetrically with respect to a vertical plane passing through the center of the optical sheet 24, and the lens group 24b is also disposed symmetrically with respect to a vertical plane passing through the center of the optical sheet 24. When the left light source 23a is turned on, the light emitted from the left light source 23a is emitted as the left side illumination light La concentrated in the direction of the peak intensity, and is emitted obliquely forward from the light exit surface 26 of the light guide plate 22. As shown in Fig. 4, the light La is redirected by the optical sheet 24 so as to converge on the left eye 27a of the observer at a predetermined distance from the surface light source device 2 1 . Similarly, when the right side light source 2 3 b is turned on, the light emitted from the right side light source 2 3 b is emitted as the right side illumination light Lb concentrated in the direction of the peak intensity, and is emitted obliquely forward from the light exit surface 26 of the light guide plate 22, and This light Lb is redirected by the optical sheet 24 in such a manner as to converge on the right eye 27b of the observer. At this time, the light Lb passing through the optical sheet 24, La, changes the direction of the light by the group 24a. When passing through the lens group 24b, the direction of the light is changed by the lens group 24b and is directed to the left eye 27a and right, respectively. The assumed position of eye 27b converges. Further, as the optical sheet 24', the lens group may not be provided in the front side, but the front surface may be formed as a flat surface. (Three-dimensional display device) Fig. 12 shows the configuration of the stereoscopic display device 31 using the surface light source device 21. In the stereoscopic display device 3!, the optical sheet 24' is superposed on the front surface of the light guide plate 22, and the frame-shaped double-sided tape 32 is bonded to the surface light source device 21 from the front. The frame-shaped double-sided tape 32 is a light absorbing member formed of a black adhesive tape -20-201227093 or the like, and is provided with an opening in a region corresponding to the light-emitting region of the light guide plate 22 and covers the front surface of the light guide plate 22. . Further, a liquid crystal panel 33 is superposed on the front side of the opening of the frame-shaped double-sided tape 32. The image for the left eye/right eye of the liquid crystal panel 33 and the lighting/extinguishing of the light source 2 3 a, 2 3 b are synchronously controlled by the synchronous driving device 34. The synchronous driving device 34 causes the left eye image and the right eye image to be alternately displayed on the left eye of the liquid crystal panel 3 3 ' and the liquid crystal panel 3 3 in a short period of the degree that the observer cannot recognize the switching of the left and right images. The left light source 23a is turned on in synchronization with the image (the right light source 23b is turned off), and the right light source 23b is turned on in synchronization with the image for the right eye (the left light source 23a is turned off). When the right side light source 2 3 b is turned on, the light Lb ’ emitted from the right side light source 2 3 b is emitted as the right side illumination light concentrated in the intensity direction, and is emitted obliquely forward from the light guide plate 22 . The light Lb emitted from the light guide plate 22 is deflected by the optical sheet 24 in such a manner that the light penetrating through each pixel is concentrated on the right eye 27 b of the observer positioned at a substantially predetermined distance from the liquid crystal panel 33. Into the liquid crystal panel 3 3 . This light Lb is converted into a right-eye image by penetrating the liquid crystal surface 3 3 and then recognized by the observer's right eye 27b. Similarly, when the left side light source 2 3 a is turned on, the light La ’ emitted from the left side light source 2 3 a is emitted as the left side illumination light in which the intensity direction is concentrated, and is emitted from the light guide plate 22 toward the oblique side. The light La emitted from the light guide plate 22 is incident on the liquid crystal panel 33 by changing the direction of the optical sheet 24 so that the light penetrating the pixels is concentrated on the left eye 27a of the observer. The liquid crystal panel 3 is penetrated and converted into an image for the left eye, which is then recognized by the left eye 27a of the observer. • 21- 201227093 So that the 'left eye image and the right eye image are alternately transported to the observer's left eye 27a and right eye 27b', but by the afterimage effect, the observer can simultaneously recognize the right eye image. The image for the left eye can be recognized as a three-dimensional image (stereoscopic image). In the stereoscopic display device 31, since the surface light source device 21' is used, the image for the left eye and the image for the right eye can be perceived. The same brightness can be used to identify a stereoscopic image with a three-dimensional effect. [Features of the first embodiment] In the light source device 2 1 of the present invention, the difference in apparent luminous intensity can be reduced by the following configuration. This reason is explained with reference to Figures 5, 13, 14 and 15. Fig. 1 (3) shows the relationship between the position of the light-emitting point in the light-emitting region (the surface of the optical sheet) of the surface light source device and the optical luminous intensity of each of the light-emitting points. Fig. 13(B) shows the relationship between the position in the light guide plate and the pattern density of the emission pattern. Further, Fig. 14 is a schematic view showing the relationship between the position of the light-emitting point and the apparent luminous intensity in the conventional surface light source device. Fig. 15 shows the relationship between the position of the light-emitting point in the light-emitting region and the apparent luminous intensity ratio. Here, the right end refers to the one end of the right side light source 23b side in the light-emitting area, and the left end refers to one end of the left side light source 2 3 a side of the light-emitting area. Further, the optical luminous intensity is based on the luminous intensity perceived by the observer's feeling, and is measured by the measuring port. ^ Called the physical state of the measured luminous intensity. In the conventional surface light source device, a straight line as shown in Fig. 1(A) is designed so that the entire light-emitting region is substantially equal in optical intensity. Therefore, in the conventional surface light source device, the emission pattern for total reflection of the light from the right side of the Μ , is set by the pattern density distribution shown in pp. -22-201227093. The emission pattern 'for totally reflecting the light of the left side light source' is set by the pattern density distribution indicated by Ga in Fig. 13(B) (see Fig. 2(B)). However, as has been explained, in consideration of the human visual sensitivity, in the case of the conventional surface light source device, as shown in FIG. 14, when the right side light source is turned on, the light emitting region is emitted from the right end. The apparent luminous intensity of the light Lb2 in the sense of the right eye is Jb2, and when the apparent luminous intensity of the left-eye sensation of the light La2 emitted from the right end when the left light source is turned on is set to Ja2, it becomes:

Jb2 &lt; Ja2. Similarly, when the right side light source is turned on, the apparent light intensity of the light Lb 1 emitted from the left end in the right eye is set to Jb 1, and the light emitted from the left end when lighting the left side light source is perceived in the left eye. When the apparent luminous intensity is set to J a 1, it becomes:

Jbl &gt; Jal. Thereby, the illuminating intensity of the image for the right eye perceived by the right eye is different from the illuminating intensity of the image for the left eye of the left eye, so that the stereoscopic effect is lowered. Further, in the case of the conventional surface light source device, as shown in FIG. 14, between the apparent luminous intensities Jb2 and Jb1 of the light emitted from both ends of the light-emitting region when the right-side light source is turned on, Has the following relationship,

Jb2&lt;Jbl has the following relationship between the apparent luminous intensity Ja2 and Jal of the light emitted from both ends of the light-emitting region when the left light source is turned on.

Ja2 &gt; Jal uses this to 'when the left side light source is lit or the right side light source is illuminated, the luminous intensity perceived by the vision is different from the left part in the right part of the light emitting area, so that it will be generated on the surface Uneven brightness. -23- 201227093 Therefore, in order to reduce the apparent intensity difference between the image for the right eye and the image for the left eye, it is necessary to be close to the following state.

Jb2=Ja2 and Jbl=Jal Therefore, the optical luminous intensity of the light Lb2 in the peak direction emitted from the right end of the light-emitting region when the right light source is turned on is set to Ib2, and is emitted from the right end when the left light source is turned on. When the optical luminous intensity of the light La2 in the peak direction is Ia2, the following formula may be used.

Ib2 &gt; Ia2 Similarly, 'the optical luminous intensity of the light Lb 1 in the peak direction emitted from the left end when the right light source is turned on is set to be the light Lai of the peak direction emitted from the left end when the left light source is turned on. When the optical luminous intensity is set to I a 1 ', the following formula may be used.

Ibl &lt; Ial As a result, in order to reduce the apparent intensity difference between the image for the right eye and the image for the left eye, the following equation may be used.

Ib2 &gt; Ia2 and Ibl &lt; iai condition (1) As long as this condition (1) is satisfied, the optical luminous intensity u2 can be made,

The Ibl knife is smaller than the apparent luminous intensity in Ib2, lai 'Fig. 14

Ja2' Jbl 'also decreases', so the apparent luminous intensity w /, Jbl difference at the left end is only small, and the apparent luminous intensity at the right end (five)

Ja2 widening is also getting smaller. As a result, the apparent difference in luminous intensity at the left and right end portions in the light-emitting region becomes small, and the three-dimensional feeling when viewed by the left eye and the right eye can be increased. In addition, when only the left side light source is illuminated (or only the right side light source is illuminated), in order to reduce the difference between the right side area and the left side area of the light emitting area, it is required to be close to the following state: -24- 201227093

Jb2=Jbl and Ja2=Jal. Therefore, the optical light intensity lb 1, Ib2 at the left and right ends when the right light source is turned on, and the optical light intensity Ial, Ia2 at the left and right ends when the left light source is turned on can be expressed as follows.

Ib2&gt; Ibl and Ia2&lt; Ial condition (2) As long as the condition (2) is satisfied, the optical luminous intensity ib 1, Ia2 is smaller than ib2, lai, respectively, and the apparent luminous intensity Jb 1 in Fig. 14 , Ja2 is also reduced, so the difference between the apparent luminous intensity Jb1 and Jb2 when the right side light source is turned on becomes small, and the difference between the apparent luminous intensity ja2 and Jal when the left side light source is turned on is also small. . As a result, it is possible to reduce the difference in intensity between the left side area and the right side area in the light-emitting area when only the right side light source is lit or only the left side light source is turned on. In order to improve the quality of the stereoscopic image observed by the observer, it is understood that the above condition (1) and the above condition (2) are satisfied. That is, as long as the following four numbers are satisfied.

Ib2&gt; Ia2

Ibl&lt; Ial Ibl&lt; Ib2

Ial&gt; Ia2 In order to satisfy the above condition (1) (2), for example, as shown in Fig. 1 (A), the optical luminous intensity of the left and right ends is defined as Ia2 = Ibl &lt; Ial = Ib2 And the optical luminous intensity la in the light-emitting region of the light La emitted from the left light source 23a is represented by a straight line connecting the luminous intensities Ia2 and Ial at both ends to connect the luminous intensities Ib2 and ibl between the two ends. The optical luminous intensity lb of the light Lb emitted from the right side light source 23b in the light-emitting area -25-201227093 may be indicated. In order to achieve such a change in the luminous intensity of the optical light, the pattern density of the emission pattern 25b (the total of the projected area of the pattern per unit area of the back surface of the light guide plate) is defined by the distribution curve Db of the first (3) diagram, and The pattern density of the emission pattern 25a may be defined by the distribution curve Da of Fig. 13(B). That is, with respect to the emission pattern 25b for reflecting the light from the right side light source 23b, the pattern density distribution curve Gb' in the case where the optical intensity of the light in the light-emitting region is averaged is as follows (assuming the shape of the light guide plate, The distribution curve Db, which is the same in size, injection efficiency, etc., increases the pattern density on the side close to the right side light source 2 3 b and reduces the pattern density on the side away from the right side light source 2 3 b . Similarly, the distribution curve Ga' of the pattern intensity in the case where the emission pattern 25 5 a for reflecting the light from the left side light source 23a is averaged on the optical intensity of the light, such as the distribution curve Da, makes the pattern density close to The side of the left side light source 23a is increased, and the pattern density is decreased on the side away from the left side light source 23a. As a result, the apparent luminous intensities Ja, Jb decrease on the side close to the respective light sources 23a, 23b, respectively, and increase on the side away from the respective light sources 23a, 23b, so that the apparent luminous intensity ratio Jb/ Ja becomes the curve Sd as shown in Fig. 15. Therefore, in the case of a conventional example in which the optical luminous intensity is averaged, the apparent luminous intensity is larger than the Jb/Jas curve S g , and is close to the curve sd. The apparent apparent luminous intensity ratio Jb/Ja=1. Further, Fig. 15 shows the relationship between the position of the light-emitting point in the light-emitting region and the apparent luminous intensity ratio. The relationship between the human visual sensitivity, that is, the viewing angle φ (the angle between the direction of the light to be recognized and the direction of the line of sight) and the sensibility of the physiological-Z6-201227093' has the characteristics of the 16th (A) graph. When the apparent luminous intensity ratio of Fig. 16 is obtained, the visual sensitivity κ(φ) of Fig. 16(A) is approximately calculated by the following equation (this Κ(φ) is shown in Fig. 16(B) ). Κ(φ) = εχρ(-α · |φ|), where α = 〇, 71 If the pattern density of the exit pattern is made into the distribution curves Da, Db, the following advantages can be obtained. The difference in brightness between the images recognized by the right eye and the left eye is reduced, so that the stereoscopic image can be easily viewed, and the difference in brightness and brightness between the left and right sides of the screen is reduced, thereby improving the quality of the image. Further, the change in the pattern density of the emission patterns 25a, 25b is reduced, and the maximum value of the pattern density is small (see Fig. 13(B)), so that the light guide plate 22 can be easily fabricated. Further, since the maximum density of the formed emission pattern is reduced, the emission efficiency from the light guide plate can be improved. Further, since the light emitted from the light sources 2 3 a, 2 3 b does not easily reach the opposite end surface of the light guide plate 22, the return light is reduced, and when used in a stereoscopic display device, crosstalk is less likely to occur. The distribution curve Mb of the emission pattern shown in Fig. 17 shows another distribution of the emission pattern 25b. If the distribution curve Db as shown in Fig. 13(B) increases the pattern density larger than the distribution curve So in the region close to the light source, and decreases the pattern density smaller than the distribution curve S 〇 in the region far from the light source. Reduce the difference in luminous intensity. In addition, the distribution curve Db is flatter than the pattern density, and the pattern density is increased more than the distribution curve Db in the region close to the right side light source 23b, and the area farther from the right side light source 2 3 b is smaller than the distribution curve Db. The distribution curve Mb of Fig. 7 which reduces the pattern density is considered. When the pattern density is further flattened as the curve Mb, the light emitted in the vicinity of the right side light source 23b is increased by -27-201227093, and when it exits the right side light source 23b, the decrease is first decreased by 18 m ^ I . Therefore, as shown in Fig. 18, the optical initial intensity Tm corresponding to the pattern density score .^ λ, - τ 〆邛 curve Mb is a ratio corresponding to the pattern screaming / knives Deng Xi #璺卜The intensity T d is more rapid. Further, in the case of the light-emitting intensity and the pattern-improvement I 匮 兄, in the figure below, only the light emitted from the right-side light source 2 and the emission pattern 25b are displayed. The light source intensity from the left side light source 23a is 4+. ^ ^ T, and the pattern density of the emission pattern 25a is the same as that of the 6丄山★攸 right source, the 23b light, and the emission pattern 25b. It is symmetrical to the left and right, and the illustration is omitted. Further, the light emission of the left side light source 23a and the right side light source 23b is strongly generated, and the emission pattern 25a and the emission pattern 25b are opposite to each other. , 饴, the way of symmetrical knife cloth formed 'and as the first! As shown in Fig. 6(B), when the observer's visual sensitivity is approximated by an exponential function, the pattern density of the emission pattern becomes a distribution curve.

In the surface light source device formed by the Mb method, the luminous intensity ratio Jb/Ja on the 砚 砚 成为 is the curve Sm of Fig. 19. When the apparent luminous intensity ratio is represented by the curve Sm, the optical luminous intensity of the light Lb2 which is emitted from the right end when the right side light source 23b is emitted from the right end and enters the right eye 27b is set to Ib2. When the optical luminous intensity of the light-emitting region that is emitted from the right end when the left-side light source 23a is emitted from the right end and enters the left-eye 27a is Ia2, the ratio Ib2/Ia2 is about 2 (for example, Ib2 is about 30,000 nit, Ia2). In the case of about 15,000 nit), the apparent luminous intensity emitted from the right end of the light-emitting region is substantially equal, so that the difference in brightness and darkness disappears. However, from the curve Sm of Fig. 19, when the distribution curve of the emission pattern is too gradual, the apparent luminous intensity ratio jb/Ja is instead from -28-.201227093

The straight line of Jb/Ja=l leaves and is therefore not suitable. That is, when the optical luminous intensity ratio I b 2 /1 a 2 is about 3.5 (for example, I b 2 is about 3 〇〇〇0 nit, and Ia2 is about l〇500 nit), the light can be improved. The emission efficiency is the same as in the case where the light-dark difference at the right end of the light-emitting region is equal to the case where the optical intensity is averaged over the entire light-emitting region, and the light emitted from the right end of the light-emitting region causes a difference in brightness between the right eye and the left eye. Thereby, in the right side region, the ratio of the optical luminous intensity satisfies the following condition (3). It is preferable that β 1.0 &lt; Ib2 / Ia2 &lt; 3.5 Condition (3) Similarly, when the right side light source 23b is to be illuminated The optical luminous intensity of the light Lb 1 which is emitted from the left end and enters the right eye 27b is lb 1 'optically the light Lai which is emitted from the left end when the left light source 23a is illuminated and enters the left eye 27a. When the luminous intensity is set to la 1 'the ratio of the optical luminous intensity in the left region of the light-emitting region is preferably the following condition (4). 1 ·〇&lt; Ial/Ibl &lt; 3.5 Condition (4) In addition, the optical luminous intensity Ia丨, Ia2, of the light emitted from the left and right ends of the light-emitting region when the left light source is illuminated 2 3 a It is also suitable to satisfy the following condition (5). l. 〇 &lt;Ial/Ia2&lt; 3 5 The same condition as the optical luminous intensity Ib1, Ib2 of the light emitted from the left end and the right end of the light-emitting region when the right-side light source 23b is turned on also satisfies the following condition (6) ) is more suitable. 1:〇曰&lt;Ib2/Ibl&lt;3 5 Condition (6) &amp;疋Because when Ia/Ia2 in condition (5) and Ib2/Ibl in condition (6) exceed 3.5, the light source side near the light emission One end of the line becomes too bright. -29- 201227093 The distribution curve Eb of the emission pattern shown in Fig. 20 shows another distribution of the emission pattern 25b. The distribution curve Gb shown in Fig. 20(A) is a pattern density distribution curve of the emission pattern for the right side light source in the case where the optical luminous intensity is averaged over the entire light-emitting region. In this distribution curve Gb, the differential value (increased rate) value is positive, and

Ik is far away from the right side of the light source, and its differential value increases (that is, the 2nd differential value is positive). Further, the differential value means that the differential value of the pattern density of the emission pattern 25b is referred to as a differential value related to the distance measured from the right end toward the left end, and the differential value of the pattern density of the emission pattern 25a is called The differential value associated with the distance measured from the left end toward the right end. The distribution curve Eb of the 20th (A) diagram is the same as the distribution curve Gb except for the end portion away from the side of the right side light source 2讣, but the differential value at the end portion 'the side away from the right side light source 2 3 b becomes for sure. For example, the pattern density of the emission pattern 25b is defined by the distribution curve Eb, and the pattern density of the emission pattern 25a is defined by a curve symmetrical with the distribution curve Eb, and the apparent luminous intensity ratio Jb/Ja becomes Curve of Figure 2(B)

The difference between the Se ′ and the characteristic of the optical illuminance intensity distribution: the lower characteristic (curve Sg) can reduce the difference in apparent illuminance between the two palpitations of the illuminating region. Further, the maximum value of the pattern density of the light-emitting area ～ 砟 can be reduced, so that the light guide shank 9 can be easily fabricated. [Second Embodiment] As a condition for making the difference between the luminous intensity of the fisherman's sputum and the left eye recognized by the right eye smaller than the conventional method, the condition is small, and only the light-emitting area is considered. Light emitted from both ends. When the following methods are designed, the entire illuminating area and the refuge can be obtained. °The conditions in the 埤. *30- 201227093 When the light is emitted from the left half of the light-emitting area as shown by the light-emitting point p 1 of Fig. 21, when the left-side light source 23a is illuminated and the right-side light source 23b is turned on, the light is incident on the light-emitting point P1. In the case where the luminous intensities are equal, the luminous intensity jb perceived by the right eye 27b is larger than the luminous intensity J a perceived by the left eye 27a. Therefore, in the case where the light-emitting point is located in the left half of the light-emitting region, 'the optical luminous intensity la when the left-side light source 23a is illuminated is designed to be larger than the optical luminous intensity ib when the right-side light source 23b is turned on. can. On the other hand, when light is emitted from the right half of the light-emitting area as in the light-emitting point P2 of Fig. 21, the optical light is emitted at the light-emitting point p2 when the left-side light source 23a is turned on and when the right-side light source 23b is turned on. When the intensities are equal, the luminous intensity Jb perceived by the right eye 27b is "smaller than the luminous intensity perceived by the left eye 27a. Thus, in the case where the luminous point is located in the right half of the luminous area, only the left side will be illuminated. The optical intensity h of the light source 23a is designed to be smaller than the optical intensity of the right side light source and 23b, that is, the point is emitted! The peak intensity direction of the first Lb of 2 7 L „ 1 ^ ^ ^ ^ ^ ^ ^ ^ 27b, which is formed by the peak intensity direction of a, is in the left half of the light-emitting region. The relationship between the two. In addition, in the case of =, "the light point P2 is % y 1 + , & the right half of the first area has |ea|&gt;|0b, therefore, if the whole light is to be emitted, The difference in degree is reduced in the illuminating region ° ° 3 by the apparent illuminating intensity condition (7). ° ° S 壬 的 发光 , , -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 -3 ; |0b|(left area), then Ia&gt; lb right is |9a| &gt; |0b| (right area), then Ia &lt; lb condition (7) In order to improve the quality of the stereoscopic image observed by the observer, As long as the above condition (7) and the condition (2) described in the first embodiment are satisfied, that is, 'as long as the following four numbers are satisfied at the same time. If |0a|&lt;|eb| (left side Region), if Ia>Ib is |ea|&gt;|eb| (right region), Ia&lt;Ib Ibl &lt; ib2 lal&gt; Ia2 The distribution curve Fb of the emission pattern 25b shown in Fig. 22(A), The change in the pattern density of the emission pattern 25b of the condition (2) and the condition (7) is not satisfied. The curve Fb is in the portion close to the right side light source 23b and the curve Gb is 'but on the side away from the right side light source 2 3 b (the left side area) ) The differential value becomes slightly smaller than the curve Gb. Therefore, the curve Fb is on the side away from the right side photovibration 23b, and the change is slightly gentler than the curve Gb, and along the curve Gb on the side where the pattern density is small. b, the pattern density of the emission pattern 2 5 b is specified, and the pattern density of the emission pattern 25a is defined by a curve symmetrical with the curve Fb, and the apparent luminous intensity ratio Jb/Ja becomes the curve of the 22nd (B) graph. Sf, a good characteristic in the case where the ideal of Jb/Ja=1 is obtained is very good. In this case, the difference in brightness between the images recognized by the right eye and the left eye is reduced, so that the stereoscopic view can be easily viewed. In addition, the difference in brightness and brightness between the left and right sides of the kneading surface is reduced, so that the quality of the image can be improved. In addition, the maximum value of the pattern density at the end portion of the light-emitting region can be reduced, so that the guide can be easily produced. The light plate 22. Further, since the maximum density of the formed pattern of the -32-201227093 is reduced, the emission efficiency from the light guide plate can be improved. In addition, the light emitted from the light sources 23a, 23b does not easily reach the light guide plate 22. Opposite side end face, so, In the case of the second embodiment, the same conditions as those of the above conditions (3) and (4) are satisfied. Preferably, the peak intensity of the light La which is emitted from the arbitrary light-emitting point when the left light source is illuminated from the light-emitting point and enters the left eye 27a is set to ia, and the light of the peak intensity la is relatively vertical. The angle formed by the normal line of the light-emitting point is Θ a ', and the peak intensity of the light Lb emitted from the same light-emitting area and entering the right eye 27b when the right-side light source 2 3 b is turned on is set to Ib. The angle formed by the light of the peak intensity lb with respect to the normal line perpendicular to the light-emitting point is set to be 'the following formula is preferable. In the case of |9a|&lt;|eb|, i.〇&lt;ia/ib&lt;3.5 is in the case of |ea|&gt;|9b|, i_〇&lt;ib/ia&lt;35 [third implementation Example 23 is an explanatory view of a third embodiment of the present invention, and the distribution curve Nb shown in Fig. 23(A) shows the pattern density of the emission pattern 25b provided on the light guide plate 22, and Fig. 23(B) shows Apparent luminous intensity. The distribution curve Db shown in Fig. 23(A) shows the distribution of a conventional emission pattern defined in such a manner that the optical luminous intensity is averaged over the entire light-emitting region. The observer's visual sensitivity has the characteristics as shown in Fig. 17(A), so if the optical luminous intensity is uniform, the apparent luminous intensity can be directly used to reflect the visual sensitivity, in the case of the conventional example. The distribution of the luminous intensity on the viewpoint becomes the curve Qo as shown in Fig. 23(B), and the center becomes brighter. -33-201227093 Therefore, in the third embodiment, as shown in the distribution curve Nb of Fig. 23(A), the pattern density of the emission pattern is inversely proportional to the curve of the display visibility. As a result, the apparent distribution of the luminous intensity becomes the curve Qn of Fig. 23(b), and becomes uniform throughout the entire light-emitting region, so that the observer can feel uniform brightness throughout the light-emitting region. [Fourth Embodiment] Fig. 24 is a schematic view of a fourth embodiment of the present invention, and an outline light source device of the present invention. The light guide plates 22a, 2 are overlapped so that the light incident end faces are located on opposite sides. The left light source 23a is opposed to the light incident end surface of the light guide plate 22a, and the light source is opposed to the light incident end surface of the light guide plate 22b. Further, on the back surface of the light guide plate, a micro-emission pattern 25a for totally reflecting light from the left side light source and emitted from the light guide plate 22a is provided at a density of a uniform sentence. On the back surface of the light guide plate 22b, a micro-emission pattern 25b for totally reflecting the light from the right-side light source 23ba and emitted from the light-emitting surface of the light guide plate 22b is also provided at a uniform density. The emission patterns 25b, 25a may be triangular or cylindrical lens-shaped emission patterns 25a across the entire width of the light guide plates 22b, 22a as shown in the '25th (A) figure, or may be A triangular-shaped or cylindrical lenticular emission pattern 25&amp; of a shorter length as shown in Fig. 25(B). Further, it may be a spherical-shaped emission pattern 25b, 25a as shown in Fig. 25(C), or an elliptical-shaped emission pattern 25b, 25a as shown in Fig. 25(D). Further, it may be a triangular pyramidal emission pattern 25a, 25b as shown in Fig. 26(A) or Fig. 100, or may be a quadrangular pyramid as shown in Fig. 26 (〇 or 26(D) In the surface light source device 41 of such a configuration, 'the difference in the apparent luminous intensity perceived by the right eye and the left eye' is satisfied as long as the above-mentioned emission pattern 25 &amp; 2 - 201227093 Condition (1) and condition (2) or the above condition (7) and condition (2) can be achieved. Fig. 27(A) is a schematic view showing changes in thickness of the light guide plates 22a, 22b in the surface light source device 41. Fig. 27(B) is a diagram showing the change in the apparent luminous intensity ratio Jb/Ja in the light-emitting region. The straight line Ha in the 27(A) diagram is shown to be emitted from the light exiting surface of the light guiding plate 22a. Light

The optical luminous intensity of La is such that the thickness of the light guide plate 22a of the comparative example is designed to be uniform in the light-emitting region, and the straight line Hbo is designed to be optically illuminated by the light Lb emitted from the light exit surface of the light guide plate 22b. In the comparison example of the thickness, the Ha in the 27th figure shows the fourth variation, the thickness of the light guide plate 2 2 a is a region where the thickness of the light guide plate is more gently, and the thickness ratio is larger than that of the Hao guide light source 23a. Hao Hb in Fig. 27 shows that the thickness of the light guide plate of the thickness of the light guide plate 22b is more gently, and the thickness ratio Hb〇 of the light source 23b is thicker than the Hb〇 intensity. The area becomes a uniform thickness variation of the light plate 22b. Further, the thickness of the light guide plate 22a of the embodiment varies depending on the thickness of the light, and the thickness of the plate near the left side light source 2 3 a is thinner than the thickness of the light guide plate away from the left side light. Similarly, the thickness of the light guide plate 22b of the embodiment varies depending on the thickness of the Hbo. The thickness of the light guide plate 22b is thinner than the thickness of the light source plate closer to the right side light source 23b, and the thickness of the light guide plate farther from the right side light is thicker. As a result, in the comparative example, the intensity of the light relative to the light in the light-emitting region is the average intensity (the line is the same as that of Fig. 13. The apparent light-emitting intensity in the light-emitting region is -35- In the case of the fourth embodiment, the light-emitting region when the right-side light source 23b is turned on is emitted from the left end and the right end in the case of the fourth embodiment. The optical light intensity m, Ib2 in the peak direction light Lb, Lb2, and the optical light intensity Ial, Ia2 between the light directions Lal and La2 in the peak direction from the left end and the right end when the left side light source 23a is illuminated The relationship is the same as the straight line Ib, la of Fig. 13, so that the apparent luminous intensity ratio jb/jfa in the light-emitting region in the case of the surface light source device 4 of the fourth embodiment becomes the 27th (B) The curve Sh of the graph, the apparent change in the luminous intensity ratio δ1ι is more gentle than the Sg. As a result, according to the surface light source device 41 of the fourth embodiment, the surface light source device 41 can be uniformly perceived by the observer. The intensity of the light on the screen. The difference between the brightness of the image recognized by the right eye and the left eye is small, so that the stereoscopic image can be easily viewed, and the difference in brightness and brightness between the left and right sides of the face can be reduced, thereby improving the quality of the image. The pattern density variation of the emission patterns 25a, 25b is reduced, and the maximum value of the pattern density is reduced, so that the light guide plate 22 can be easily fabricated. Further, since the maximum density of the formed emission pattern is reduced, the guidance can be improved. In addition, since the light emitted from the light sources 23a and 23b does not easily reach the opposite end surface of the light guide plate 22, the return light is reduced, and when used in a stereoscopic display device, crosstalk is less likely to occur. The figure shows a variation of the thickness of the light guide plate 22b (the light guide plate 22a is omitted), and the variation 1 and the modification 2 are different. The curve Hb of the 28th (A) diagram and the curve Shi of the 28th (B) diagram show the present embodiment. In the variation of the example 1, the curve H2b of the 28th (A) and the curve Sh2 of the 28th (B) show the variation 2 of the embodiment. -36- 201227093 s The thickness variation Hb is linearly reduced and has Certain inclination 'but In the thickness variation of the variation 1 shown by the curve Hlb of the 28th (A) diagram, the same is true in the case where the thickness of the light guide plate 22b is thinned away from the right side light source 23b, but in the case of Η 1 b, Far from the right side light source 23b' the decrease rate of the thickness becomes smaller (the absolute value of the differential value of Η 1 b decreases). In this case, the apparent luminous intensity ratio Jb/Ja becomes the curve Shi of the 28th (B) figure. This is similar to the curve Sh. In addition, in the thickness variation of the variation 2 shown by the curve H2b of the 28th (A) graph, the decrease rate of the thickness gradually becomes smaller (that is, the second differential value of the curve H2b is positive. In the region away from the right side light source 23b, there is a minimum value of thickness 'and the thickness is slightly increased in the region away from the right side light source 23b. In this case, the apparent luminous intensity ratio Jb/Ja becomes the curve Sh2 of the 28th (B) diagram. [Fifth Embodiment] Fig. 29 is an explanatory view showing a fifth embodiment of the present invention, in which the curve Rb shown in Fig. 29(a) shows the thickness variation of the light guide plate 22b, and the 29th (b) figure shows the appearance. Luminous intensity. The distribution curve Db shown in Fig. 29(A) shows the distribution of a conventional emission pattern defined by averaging the optical luminous intensity in the entire light-emitting region. The observer's visual sensitivity has the characteristics as shown in Fig. 17(A), so 'if the optical luminous intensity is uniform, the apparent luminous intensity can be directly used to reflect the visual sensitivity, in the conventional example. The apparent luminous intensity distribution becomes the curve q〇 of the 29th (B) graph, and the center becomes brighter. -37-201227093 Thus, in the fifth embodiment, as shown in the distribution curve Rb of Fig. 29(A), the thickness of the light guide plate 22b is inversely proportional to the curve of the display visual sensitivity, and the apparent luminous intensity becomes the first The line shown in Figure 29(B)

Qr becomes uniform throughout the illuminating area, so that the observer can feel uniform brightness throughout the illuminating area. [Sixth embodiment] Fig. 30 is a schematic view showing a surface light source device η according to a sixth embodiment of the present invention. In this embodiment, the apparent luminous intensity in the light-emitting region is adjusted by adjusting the aperture ratio of the liquid crystal panel 33. In the surface light source device 5 1 ', the optical illuminating intensity of the surface of the optical sheet 24 may be made optically equal to the illuminating intensity, as shown in the 30th (A) figure, the right side light source 23b In the case of observing the right eye 27b, the well is shot from the left and enters the well 27b of the right eye. 々 μ々 姐 itch. The first light of Lb 1 is strong: light intensity = end shot and enter the right eye W Therefore, in the present embodiment, the optical layer of the light (1) can be made to have a shape on the liquid crystal panel (so that the pixel at the left end of the facet is partially shielded from the center of the light (to be shielded from the light)螂. 1 + The center of the heart, the pixel, in the unrecognizable way to the eye 27b of the light, the result, from the left end of the screen into the right left end and the right end of the door, 艮 27b, can reduce the picture The difference in the apparent luminous intensity between the U. As shown in the figure, when the left left eye 27a is illuminated, the image on the right end of the screen is displayed on the 33: The left image reduces the amount of light transmission 1 result, from the state of the written ::: part shading, the right end enters the left eye 27a -38- 201227093 The amount is reduced. Therefore, in the left eye 27a, the difference in apparent luminous intensity between the left end and the right end of the screen can be reduced. [Simplified illustration] 1(A) and 1(B) is a schematic view for explaining the principle of the stereoscopic display device. Fig. 2(A) is a schematic view showing the distribution of the luminous intensity in the light-emitting region of the conventional surface light source device used in the stereoscopic display device. (B) is a schematic view showing a distribution of a pattern density of an emission pattern for emitting light from the left side light source from the light exit surface and a pattern density of an emission pattern for emitting light from the right side light source from the light exit surface. 3 (A) is an explanatory diagram for explaining the reason why the apparent luminous intensity perceived by the right eye is different from the apparent luminous intensity perceived by the left eye. Fig. 3(B) is on the right A schematic diagram showing the change in the ratio of the apparent luminous intensity perceived by the eye to the apparent luminous intensity perceived by the left eye. Fig. 4 is a view for explaining the light emitted from the left side region of the light emitting region and the right region. The apparent luminous intensity of each of the emitted light BRIEF DESCRIPTION OF THE DRAWINGS Fig. 5 is a schematic cross-sectional view showing a surface light source device according to a third embodiment of the present invention. Figs. 6(A) and 6(B) are views showing a surface light source device used in the first embodiment. A schematic cross-sectional view of the light guide plate [6th (A) shows an emission pattern for totally reflecting light emitted from the right side light source, and FIG. 6(B) shows an emission for total reflection of light emitted from the left side light source. -39- 201227093 Fig. 7(A) is a view showing an example of an emission pattern provided on the back surface of the light guide plate. Figs. 7(B) and 7(C) are a perspective view and a cross-sectional view of the emission pattern. (A) is a schematic view showing another example of an emission pattern provided on the back surface of the light guide plate. Figs. 8(B) and 8(C) are a perspective view and a cross-sectional view of the injection pattern. Fig. 9(A) is a view showing another example of an emission pattern provided on the back surface of the light guide plate. Fig. 9(B) and Fig. 9(C) are a perspective view and a cross-sectional view of the injection pattern. Fig. 10(A) is a schematic view showing still another example of the emission pattern provided on the back surface of the light guide plate. Figures 10(B) and 10(C) are a perspective view and a cross-sectional view of the injection pattern. Fig. 11 is a detailed view showing the sectional shape and optical action of the optical sheet. Fig. 1 is a schematic cross-sectional view showing a stereoscopic display device using the surface light source device of the first embodiment. Fig. 1 (3) is a view showing the relationship between the position of the light-emitting point in the light-emitting region of the surface light source device and the optical luminous intensity of each of the light-emitting points. Fig. 13(B) is a view showing the relationship between the position in the light guide plate and the pattern density of the emission pattern. Fig. 14 is a schematic view showing the relationship between the position of the light-emitting point and the apparent luminous intensity in the conventional surface light source device. Fig. 15 is a view showing the relationship between the position of the light-emitting point in the light-emitting region and the apparent luminous intensity ratio. Figure 16(A) is a schematic diagram of the human visual sensitivity. Figure 16(B) is a schematic diagram of the apparent sensitivity after approximating the exponential function. -40- 201227093 Figure 17 is a schematic diagram of the pattern density distribution curve of the shot pattern. Fig. 18 is a view showing the relationship between the position of the light-emitting point in the light-emitting region and the optical luminous intensity. The 19th is a schematic diagram showing the relationship between the position of the light spot and the apparent luminous intensity ratio. Fig. 20(A) is a schematic view showing a pattern density distribution curve of an emission pattern. Fig. 20(B) is a view showing the relationship between the position of the light-emitting point in the light-emitting region and the apparent luminous intensity ratio. Fig. 2 is an explanatory view showing a second embodiment of the present invention for explaining an angle formed between a peak direction of light emitted from a light-emitting region and a normal direction of a vertical light-emitting point. A 22 (A) diagram is a schematic view of the pattern density distribution of the emission pattern in the light guide plate. Fig. 22(B) is a diagram showing the relationship between the position of the light-emitting point in the light-emitting region and the apparent luminous intensity ratio. Fig. 23 is an explanatory view showing a third embodiment of the present invention, wherein Fig. 23(a) is a schematic view showing a pattern density distribution of an emission pattern, and Fig. 23(B) is a schematic view showing apparent luminous intensity. Figure 24 is a schematic view showing a surface light source device according to a fourth embodiment of the present invention. Fig. 25(A) is a rear elevational view showing an emission pattern formed on a light guide plate formed in the surface light source device of the fourth embodiment. Fig. 25(b) is a rear elevational view showing another emission pattern formed on a light guide plate of the surface light source device of the fourth embodiment. Fig. 25(c) is a rear elevational view showing the other-emission pattern formed on the light guide plate formed in the surface light source device of the fourth embodiment. Fig. 25(D) is a rear elevational view showing still another emission pattern formed on a light guide plate of the surface light source device of the fourth embodiment. -41 - .201227093 Fig. 26(A) is a rear view showing another pattern of formation on a lead plate in the surface light source device of the fourth embodiment in the formation of -(iv)柘h. Fig. 26(B) is a rear view showing the re-spray pattern formed on the fourth embodiment of the fourth embodiment: the light guide plate m Λ Ψ ^ Μ ^ ^ j. 26 (C) The figure is a rear view showing still another emission pattern formed on the J light guide plate in the surface light source device of the fourth embodiment. Figure 26(D) Figure A ss-() is a diagram not shown in the fourth embodiment.

A rear view of another A of the light guide plate on the light guide plate. Example. Fig. 27(A) is a view showing the thickness of the light guide plate in the face 総 device of the fourth embodiment, which is not shown in Fig. 27(A). Fig. 27(B) is a view showing the change in the apparent luminous intensity ratio of the surface light source device. Fig. 28(A) is a view showing a change in thickness of the light guide plate in a variation of the fourth embodiment. Fig. 28(B) is a view showing the change in the apparent luminous intensity ratio of the modification. Fig. 29(A) is an explanatory view showing a fifth embodiment of the present invention, wherein Fig. 29(A) is a schematic view showing a change in thickness of a light guide plate, and Fig. 29(B) is a view showing an apparent luminous intensity. Fig. 30 (A) and (B) are schematic views showing a surface light source device according to a sixth embodiment of the present invention. [Description of main component symbols] 2 1,4 1,5 1 Surface light source device 22, 22a, 22b 23a 23b Left side of light guide plate Light source for right side Light source optical sheet -42- 24 201227093 24a Prism group 24b Lens group 25a, 25b Exit pattern 26 Light exit surface 27a Left eye 27b Right eye 28 Reflector 3 1 Stereoscopic display device 32 Frame-shaped double-sided tape 33 Liquid crystal panel 34 Synchronous drive device La, Lb Light-43-

Claims (1)

201227093 VII. Patent application scope: 1. A surface light source device, comprising: a light guide plate for guiding light incident from a pair of opposite light incident end faces to emit the light from the exit surface; a light source, wherein light is incident from one of the light incident end faces toward the light guide plate; and the second light source is configured to direct light from the other of the light incident end faces toward the guide And the prism sheet is disposed to face the light of the light guide plate; the surface light source device is characterized in that: the first light source is illuminated from the first light source The peak intensity of the light emitted from the end portion on the light source side is Ial, and when the peak intensity of the light emitted from the end portion on the first light source side in the light-emitting region when the second light source is turned on is lb 1 , it becomes Ial> Ib1; a peak intensity of light emitted from an end portion of the light-emitting region when the first light source is turned on from the second light source side is Ia2, and a light-emitting region when the second light source is turned on is from the second Light source side Peak intensity of the light emitted portion Ib2 set time, become Ia2 &lt; Ib2. 2. A surface light source device comprising: a first light guide plate that guides incident light to emit the light from a light exit surface; -44- 201227093 second light guide plate, which is guided by the light guide The light is emitted from the light exit surface; the first light source is configured to inject light from the light incident end surface of the first light guide plate toward the first light guide plate; the second light source is configured to cause light from the foregoing The light incident end surface of the second light guide plate is incident on the second light guide plate; and the prism sheet; wherein 'the first light guide plate and the second light guide plate are overlapped to each other on the opposite side of the light incident end face, Having a shuttle lens disposed to face light of a light guide plate located on a front side of the first light guide plate and the second light guide plate; the surface light source device is characterized by: illuminating when the first light source is turned on The peak intensity of the light emitted from the end portion on the first light source side in the region is ial, and the peak intensity of the light emitted from the end portion on the first light source side in the light-emitting region when the second light source is clicked is set. When it is Ib 1, it becomes Ial> Ibl; The peak intensity of the light emitted from the end portion of the second light; the original side light portion of the light-emitting region when the first light source is turned on is ia2, and the light-emitting region when the first two light sources are turned on is emitted from the second light source When the peak intensity of the light emitted from the end portion of the side is Ib2, it becomes Ia2 &lt; Ib2. The surface light source device of claim 1 or 2, wherein -45 - 201227093 sets a peak intensity of light emitted from an arbitrary light-emitting point of the light-emitting region when the first light source is avoided, and sets the peak intensity The angle formed by the light of la with respect to the normal line of the vertical light-emitting point is set to 0a'. When the peak intensity of the light emitted by the second light source point is set to be light with respect to the vertical light-emitting point, In the case of lb, the angle formed by the normal of the peak intensity lb is 〇b 丨0al&lt;|eb|, and Ia&gt; Ib, l〇a| &gt; |0b| is Ia&lt; Ib . 4. The surface light source device of claim 3, wherein the angles 0a, 0b and the peak intensity ia, Ib is |0a| &lt; |0b|, the condition ' becomes 1 〇&lt; ia/Ib &lt;; 3 5, |〇a|&gt;|0b| The case 'is i〇&lt;ib/Ia&lt;3.5. 5. The surface light source device according to claim 1 or 2, wherein a peak intensity of light emitted from an end portion of the light-emitting region when the first light source is turned on from the first light source side is set to I a 1 When the ridge intensity of the light emitted from the end portion on the second light source side of the light-emitting region when the first light source is turned on is 1a2, the condition of Ial &gt; Ia2 is satisfied, and the second light source is turned on. The peak intensity of the light emitted from the end portion on the second light source side in the light-emitting region is Ib2, and the ridge value of the light emitted from the end portion on the first light source side of the light-emitting region when the second light source is turned on When the intensity is set to lb 1, the condition of Ib2 &gt; lb 1 is satisfied. 0 46- 201227093 6 · The surface light source device of claim 5, wherein 'the aforementioned peak intensity Ial, Ia2 satisfies l.〇&lt;Ial/Ia2&lt; The condition of 3.5, the aforementioned peak intensity Ib1, Ib2 satisfies the condition of 1.0 &lt; Ib2 / Ibl &lt; 3.5. 7. The surface light source device of claim 1, wherein the light exit surface of the light guide plate or the surface facing the light exit surface is formed to form light for injecting light from the first light source from the foregoing a first emission pattern emitted from the light exit surface and a second emission pattern for emitting light incident from the second light source from the light exit surface. 8. The surface light source device of claim 2, wherein the light exiting surface of the first light guide plate or the surface facing the light exit surface is formed to form light for injecting light from the first light source a first emission pattern emitted from a light exit surface of the first light guide plate is formed on a light exit surface of the second light guide plate or a surface facing the light, so as to be incident from the second light source The light is emitted from the second emission pattern of the light exit surface of the second light guide plate from the month 1J. 9. The surface light source device of claim 7 or claim 8, wherein the first emission pattern is configured to increase the pattern density in a nonlinear function manner away from the first light source, away from the foregoing The rate of increase of the pattern density in the direction of the light source is constant, and as the distance from the first light source is increased, the increase rate is gradually increased, and a second emission pattern is configured to be separated from the second light source by a pattern density. The nonlinear function mode is increased, and the increase rate of the pattern density in the direction away from the first light source is constant, and the aforementioned increase rate is gradually increased away from the second light source. The surface light source device of claim 9, wherein the first emission pattern is in a region away from the first light source in a central portion of the light-emitting region, and the first direction away from the first light source is first. The increase rate of the pattern density of the emission pattern is smaller than the distribution of the pattern density of the first emission pattern in such a manner that the light of the emission intensity is emitted from the light exit surface, and the second emission pattern is in the center of the light-emitting area. In the region of the two light sources, the pattern density of the second emission pattern is increased from the direction in which the second emission pattern is farther away from the second emission pattern than the light from which the illumination intensity is assumed to be emitted from the light exit surface. smaller. 1. The surface light source device of claim 9, wherein the first emission pattern is in a region of the first light source in a central portion of the light-emitting region, and the pattern of the first emission pattern is away from the first light source. The increase rate of the density is constant, and the second emission pattern is in a region of the second light source in the center of the light-emitting region, and the increase rate of the pattern density of the second emission pattern in the direction away from the second light source is constant. 12. The surface light source device of claim 7 or 8, wherein the first emission pattern is in a region of the first light source in a central portion of the light-emitting region, and the first emission pattern is patterned away from the first light source. Decreasing, in the region farther from the first light source than the light-emitting region, increasing the density of the first emission pattern as the distance from the first light source is increased, and further away from the upper portion, so that the uniform configuration is farther from the upper front and evenly arranged. Farther away from the upper front, farther away from the upper front, closer to the density with the central pattern -48-201227093 The second shot pattern is in the region of the second light source than the center of the light-emitting region, so that the second shot is emitted The pattern of the pattern is reduced as it is away from the second light source, and the density of the second exit pattern pattern increases as it moves away from the second light source in a region farther away from the second light source than the center of the light emitting region. 13. The surface light source device of claim 2, wherein the thickness of the first light guide plate is gradually thinner from an end surface opposite to a light incident end surface of the first light source pair toward the light incident end surface, The thickness of the two light guide plates is gradually thinner from an end surface opposite to the light incident end surface of the second light source pair toward the light incident end surface. 14. The surface light source device of claim 13, wherein the thickness of the first light guide plate is more gently changed than a thickness change of light that is assumed to emit a uniform light emission intensity from a light exit surface of the light guide. The thickness of the second light guide plate is changed more gently than the thickness change of light which is assumed to emit uniform light emission intensity from the light exit surface of the light guide. The surface light source device of claim 14, wherein the thickness of the first light guide plate and the thickness of the second light guide plate are uniformly reduced by a certain ratio. 1. The surface light source device of claim 13, wherein the reduction rate of the thickness of the first light guide plate becomes smaller as the end portion away from the side of the first light source becomes smaller, in close proximity The direction change plate flatness is close to -49-201227093 The thickness of the second light guide plate is reduced by the thickness of the side away from the side of the second light source. 17. The surface light source device of claim 2, wherein the thickness of the first light guide plate is thinner from an opposite side of the light incident end surface toward the light incident end surface, at an end portion away from the side of the first light source. The thickness of the second light guide plate is gradually thinner from the opposite side of the light incident end surface toward the light incident end surface, and the end portion of the end portion away from the side of the second light source is Gradually thicker. 18. The surface light source device of claim 17 in the first light guide plate and the second light guide thickened region, wherein the thickness is in a certain ratio. 19. A stereoscopic display device, characterized in that: An optical sheet and a liquid crystal panel are disposed on the surface of the first or second aspect of the patent application. As the rate decreases, the opposite end faces of the first light source gradually change toward the front end. The opposite end faces of the second light source gradually change toward the front end, wherein the thickness in the plate gradually increases by σ. Front of the light source device -50-