1293709 玖、發明說明： 【發明所屬之技術領域】 本發明是關於用來作為對於液晶彩色電視或液晶監視 器等液晶顯示面板（被照明構件）進行面狀照明之背光等的 面光源裝置，以及具有此面光源裝置的圖像顯示裝置，而 且是關於這些面光源裝置及圖像顯示裝置所使用的 組裝體。 九板 【先前技術】 (第1習知例） 例如行動電話或攜帶型液晶彩色電視等由於要求 動性，因此是使用小型化的圖像顯示裝置。另_方面夕 型液晶彩色電視或各種液晶監視器等的 以帶著走為前提。帛16圖是此 二置卫不 土八 < 圔像顯不裝置的箆1 例。如該圖所示，面光源裝置54 勺弟 -有擴放板50，在其背 (图式中下面）側平行配置有複數 51的弁曰〜# I錢数個螢先燈51，該螢光燈 勺先疋攸擴散板5〇的出射 可照明液日曰5 _ 以面狀射出。此出射光< 曰日頒不面板等的被照明構件53 0 是這種構造有其缺點。亦即，由；^ f j & 光的均一化， 丨由於而要谋求出射 所以裝置的厚度⑺ /放板50的距離’ ,, ^曰夂Α 全體重量也會仏 便。 有限的工間内也不容易搬運，相當不方 (第2習知例） 另外’較大型之圖像顯裝 衣夏所使用的面光源裝置已 314883 5 1293709 知有第17圖所示的面光源裝置56。此面光源裝置56是在 導光板57之相互位於相反側的兩側面（兩入射面）8a、 附近分別配置複數個螢光燈丨〇，並且將來自這些複數個螢 光燈ίο的光從兩入射面8a、8b導入導光板57内。此光在 V光板5 7内傳播的過程當中會從出射面$ 8以面狀射出。 此構造當中，裝置的厚度（T2)比第1習知例之裝置的 厚度（T1)小（ΤΙ > T2)。因此，使用面光源裝置56的圖像顯 不衣置60比使用第i習知例之面光源裝置54的圖像顯示_ 裝置55更適合小型化（薄型化）、輕量化，搬運也比第1習 知例輕鬆。 (第3習知例） 第1 8圖疋車父大型之圖像顯示裝置所適用的另一個習 决口 ^[列。士口兮女同一 e 、 μ "斤不，面光源裝置61與前述第2習知例同樣 疋在導光板Λ > . 的兩側面（兩入射面）8a、8b附近分別配置斿 數個榮光、擦1 π / « 。但疋’在導光板62的剖面形狀下過工夫。 也就是以板厚太1 土 最小、 子在導先板62之背面63側的大致中央部形成 、、使板厚從兩入射面8 a、8 b向大致中央部逐漸 減少。因此，石、丨… Ψη 光源裝置61比第2習知例的面光源裝置 ^易射出在導光板62内部傳播的光。 果比起第2習知例的面光源裝置56更可提高出射 兀冗度。亦gp A 4 顯示裝置/ 第3習知例之面光㈣置61的圖像 量化。而且4比第1習知例更容易實現小型化（薄型化）、輕 【發明内第2習知例更可謀求出射光的高亮度化。 314883 6 1293709[Technical Field] The present invention relates to a surface light source device used as a backlight or the like for planarly illuminating a liquid crystal display panel (illuminated member) such as a liquid crystal color television or a liquid crystal monitor, and An image display device having such a surface light source device, and an assembly used for these surface light source devices and image display devices. Nine Boards [Prior Art] (First Conventional Example) For example, a mobile phone or a portable liquid crystal color TV is required to be compact, and therefore it is a small-sized image display device. Another _ eve eve type LCD color TV or various LCD monitors, etc. take the premise. The 帛16 picture is the first case of the second set of guards. As shown in the figure, the surface light source device 54 has a scooping plate 50 with a plurality of expansion lamps 50, and a plurality of fluorescing lamps 51 having a plurality of 51 in the back (the lower side in the drawing) side are arranged in parallel. The light scoop is first emitted from the diffuser plate 5 可 illuminating liquid 曰 5 _ is emitted in a plane. This outgoing light < 被 颁 颁 颁 面板 面板 面板 面板 面板 面板 面板 面板 面板 面板 面板 面板 面板 面板 。 。 。 。 。 。 That is, the uniformity of the light is satisfied by the ^f j & light, so the thickness of the device (7) / the distance of the plate 50 is lowered, and the total weight of the device is also reduced. In the limited work space, it is not easy to carry, and it is quite unreasonable. (Second conventional example) In addition, the surface light source device used in the larger image display clothing summer is 314883 5 1293709. Light source device 56. The surface light source device 56 is provided with a plurality of fluorescent lamps 附近 on the opposite sides (two incident surfaces) 8a of the light guide plate 57 on opposite sides, and light from the plurality of fluorescent lamps ίο The incident surfaces 8a and 8b are introduced into the light guide plate 57. This light is emitted from the exit surface $8 in a planar manner during propagation in the V-plate 57. In this configuration, the thickness (T2) of the device is smaller than the thickness (T1) of the device of the first conventional example (ΤΙ > T2). Therefore, the image display device 60 using the surface light source device 56 is more suitable for miniaturization (thinning) and weight reduction than the image display device 55 using the surface light source device 54 of the first conventional example, and the transport is also better than the first 1 The familiar example is easy. (Third conventional example) Fig. 18 shows another application for the image display device of the grandfather of the car ^[column. The scorpion niece is the same as e, μ " 面, the surface light source device 61 is arranged in the vicinity of the two side faces (two incident faces) 8a, 8b of the light guide plate gt > Glory, rub 1 π / «. However, 疋' works under the cross-sectional shape of the light guide plate 62. That is, the thickness is too large, and the soil is formed at a substantially central portion on the side of the back surface 63 of the guide plate 62, and the thickness is gradually reduced from the two incident surfaces 8a and 8b toward the substantially central portion. Therefore, the stone, 丨... light source device 61 is more likely to emit light propagating inside the light guide plate 62 than the surface light source device of the second conventional example. It is possible to improve the emission redundancy more than the surface light source device 56 of the second conventional example. Also, the image of the gp A 4 display device / the third conventional example (4) 61 is quantized. Furthermore, it is easier to achieve miniaturization (thinning) and lighter than the first conventional example. [In the second conventional example of the invention, it is possible to obtain a high luminance of the emitted light. 314883 6 1293709
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(發明之目的） 如上所述，第2習知例及第3習知例比第丨習知例更 容易實現小型化（薄型化），但還是無法充分因應近年來對 於消耗電力降低化的強烈需求。 因此，本發明之目的在於提供一種可避免出射光亮度 降低，又可謀求消耗電力之降低化的面光源裝置、使用該 面光源裝置的圖像顯示裝置，以及這些裝置所使用的導= 板組裝體（組合體）。 (解決問題之技術手段） 本發明的面光源裝置具有第丨導光板及第2導光板。 在此’第1導光板具有相互位於相反侧的兩側面（人射面）， 且在各側面（入射面）附近分別配置有第丨光源及第2光 源。來自這些第1及第2光源的光在通過前述兩侧面而被 導入導光板内—之後，會從出射面以面狀的照明光射出。 而且，在第1導光板的背面係以使前述第工導光板之 在前述第i側面與前述第2側面之間之大致中央部為最薄之方 式形成有導光板卡合凹處，前述第2導光板之出射面側係 與前述第1導光板之背面側對應之形狀，且第2導光板係 其出射面側接近前述第i導絲之背面側之方式收容在導光板 卡口凹$。另夕卜’在第2導光板的背面形成有光源收容凹處， 且在該處收容有第3光源。 ，猎由組合上述面光源裝置以及由該面光源裝 所照明的被照明構件，即構成本發明的圖像顯示裝置。 々f ^古亦可將在上述第1導光板之背面的導光板卡 凹處收谷有料第2導光板者用來作為上述面光源裝置 圖像顯不裝置所使用的導光板組裝體 【實施方式】 ) 以下 苓妝圖式來详細說明本發明的實施形態。 314883(修正頁） 7 !2937〇9 [第1實施形態] 第1圖至第5圖是本發明第1實施形態的圖像顯示裝 … 置1。首先第1圖是圖像顯示裝置1的分解斜視圖。另外， 第2圖是第1圖之圖像顯示裝置1所使用的面光源裝置2 r 的外觀斜視圖。第3圖是第1圖的圖像顯示裝置1的前視 -圖。另外，第4圖是從第3圖的A方向觀看面光源裝置2 的圖。而第5圖是去除第3圖所示之面光源裝置2的反射 片3後的面光源裝置2的後視圖（從第3圖的B方向觀看的鲁 · 圖）〇 (圖像顯示裝置的概略構成） 在這些圖式當中，將第2導光板6重疊配置於第1導 光板4的背面5側，藉此構成導光板組裝體7。第i導光 板4具有相互位於相反側的一對側面（入射面）。而 且，在側面（入射面）8a附近配置有作為第丨光源的棒狀螢 光燈，在側面（入射面）8b附近配置有作為第2光源的棒狀 螢光燈。這些最好是相同尺寸、相同形狀、相同型式的螢 光燈’兩者皆以符號10表示。 另外，在第2導光板6之背面11{則（第i圖中的下面 側）的中央邛有作為第3光源的棒狀螢光燈丨2配置成大致 與螢光燈10、10平行的狀態。 射面（第1圖中的上面）i 3 1 4以作為被照明構件， 面Π的方式配置有反射 與液晶顯示面板1 4之間 以相對向於第1導光板4之出 的方式’重疊配置有液晶顯示面板 並且以相對向於第2導光板6之背 片3 °此外，在上述第1導光板4 314883 8 1293709 亦可看情況適當配置擴散片或稜鏡片等作為光控制構件。 如上所述，本實施形態是使上述螢光燈丨〇、1 〇、i 2、 苐1導光板4、第2導光板6構成以面狀照明液晶顯示面 板14的面光源裝置2。而且，可藉由此面光源裳置2明明 液晶顯示面板1 4。 (導光板組裝體） 導光板組裝體7是由第1導光板4及第2導光板6所 構成。各導光板是使用 PMMA(P〇lymethylmethac]rylate: 聚甲基丙烯酸甲酯）、PC(p〇lyCarb〇nate聚碳酸g旨）、環稀 (cyCl0〇lefin)系樹脂材料等透光性佳的材料而形成。 第1導光板4是以板厚從一對入射面8a、8b當中的一 方朝另一方逐漸減少，而且板厚在入射面8a、8b間之大致 中央部變付取薄的方式，使背面5形成光滑的圓弧面。出 射面1 3是形成平坦面。 亦即’ f 1導光板4是如第3圖所示，以左右方向丨 中央部CL為界形成左右對稱的形狀，且具有板厚從各乂 射：8a、8b朝中央部CL逐漸減少的剖面形狀。而且， 方、疋使月面5側朝向斜上方傾斜’因此在内部傳播之 螢光燈1〇、1〇的光更容易由背Φ 5反射。結果，光便可; 出射面1 3有效射出。 ^外糟由使月面5形成圓弧面形狀，可確保用來 …光板6收容在背面5側的空間(導 : 第2導光板6是盥第 、 冷光板4的背面5側重疊， /、上面（出射面）1 6側呈右似 〗有對應於第1導光板4之背面5 314883 9 1293709 的形狀。而且是以中央邻 , 兴^ CL的板厚最厚的方式彎曲而形 Ϊ。：且，第2導光板6在重疊於第^導光板4的情況下， 二月面（下面）U側是形成大致平行於第1導光板4之出射 面1 3的平坦面。 、一亦即’备將昂2導光板6重疊於第1導光板4而構成 ¥光板組裝體7時，第莫 1乐九板4的出射面π與第2導光 板6的背面11是大致平行。而且，在此第2導光板6的背 = 11，而且在第3圖的左右方向大致中央部形成有用來收鲁 :螢光燈12的光源收容凹處17。光源收容凹處17是朝向 沿著第1導光板4之入射面8a、8b的方向延伸設置，而且 為了使f光燈12的光有效地射人第2導光板6内，使剖面 形狀大致形成半圓形狀。 在此，本實施形態中的導光板組裝體7當將第2導光 板6的出射面16重疊於第i導光板4的背面5側而加以組 3 ¥，疋在第1導光板4之背面5側的空間15内收容第2 ‘光板6，並且使第1導光板4之入射面8a、8b側的板厚鲁 形成導光板組裝體7的厚度尺寸。因此，藉由使用此導光 板組裝體7 ’可避免面光源裝置2的大型化。 (反射片） 反射片 3 是由白色 PET(polyethylene glycol terephthalate :聚對苯二甲酸乙二醇酯）等光反射性佳的材 料所形成，並且形成與第2導光板6之背面11大致相同大 小的矩形形狀。反射片3是使從第2導光板6之背面11 射出的光擴散、反射而回到第2導光板6内部，可有效利 10 314883 1293709 用來自螢光燈10、10、12的光。 (燈管反射器） 燈管反射器18、18是由白色PET等光反射性佳的樹 脂材料、或是不鏽鋼板或鋁板等光反射性佳的金屬材料所 形成。燈管反射器18、18的上端緣是卡合在構成導光板組 裝體7的第1導光板4之出射面13的端緣。而下端緣是卡 合在反射片3的下面側端緣。燈管反射器丨8、丨8具有使來 自螢光燈1 0、1 0的光朝向入射面8a、8b的功能。 馨 (本實施形態的作用•效果） 如以上構成的本實施形態當中，光的行進方式如以下 所述。從螢光燈12發出的光從第2導光板6的光源收容凹 處17的表面射入第2導光板6内部之後是在第2導光板6 内部傳播，在該過程中，相對於上面(出射面)16的入射角 為臨界角以下的光會從第2導光板6的出射面16射出。此 光會從第1導光板4的背面5側射入第1導光板4的内部。 另外，從螢光燈10、1〇發出的光直接或由燈管反射器鲁 U、18反射之後是從入射面仏、讣射入第i導光板4内 並且與經由第2導光板6射入之來自螢光燈I]的光一 起在弟1導光板4内部傳播。 在此過程當中，相對於出射面1 3的入射角為臨界角以 下的光T從出射面η射出至外部。然後，從出射面13射 出的光疋以面狀照明被照明構件（液晶顯示面板）1 *。 在此，第2導光板6由於是從背面11導入螢光燈12 的光，因此比起從導光板之側面導入光的樣態，較沒有浪 314883 11 1293709 費’且光的利用效率（朝向第1導光板4的射出效率）較高。 合亡而且’由於不需要並列配置複數個螢光燈10,因此不 會有被鄰接的萘#、批,n t ^ 且1〇所吸收的光，而可提升螢光燈 1 〇的先的利用效率。 6 可利用來自配置於第2導光板 足螢月光产:的寬度方向中央部以的營光燈12的光來補 疋蛍光燈10、10的氺 、 不易到達之部分，即第1導光板4 、一附近的出射光的亮度，且可利用來自第2導 ^反6的出射光直接照明第1導光板4的背面5側，因此· 來…導光板4的出射光效率比第17圖及第二此· 的習知例更為提升。 弟18圖所不 因此，使用導光板組裝體7的面光源裝置可用較少的 心、（螢光燈10、1〇、12)而實 之A奋仏 α j習知例同樣 儿度均一的照明光射出性能。亦即，比起如第 1 8圖所*，在各入射面8a、8b附近分別配署 ⑥弟 ^ 1 η AA ^ W迎刀別配置複數個螢来 且、2至第3習知例，消耗電力會減少。 面5二且’由於第2導光板6是收容在第1導光板4的北 *貞，因此導光板組裝體7的厚度尺寸就是第： 之入射面8a、8b側的板厚尺寸，而 ’反 2:大型化。因此，本實施形態的面光源:裝置^ 圖所示的第i習知例更適合小型化 2比起弟16 [第2實施形態] 化。 第6圖是第2實施形態之圖像顯示 光源_ @ 0 S 1所使用的ft 原衣置2。/亦即，面光源裝i 2具有將笛" 1面 板厚最薄的中央部加以左右分割 '光板4在 d与弟1分割片 3】4883 12 1293709 乜及第2分割片4b兩部分）的構成。 根據這種構成，由於第丨導 左右對稱形狀，可以僅利 射出成形用模具來形成第i導:板4的方: 刀…、仆。因此，根據本實施形態， 1實施形態同樣的效果，且可使 ：…弟 產品價格的低絲。 使廉化，並謀求 此外，本實施形態的面光源裝置2最好是在第i導光 y的出射面13側配置擴散片（未圖示），並利 來自第1導光板4的出射光擴散、透過，藉此使第 板4的分割部不易看見。 [第3實施形態] 第7圖是第3實施形態之圖像顯示裳置上所使用的面 先源裝置2。本實施形態的面光源裂置2是在第i導光板4 的背面5與第2導光板6的出射面16之間配置有用來使來 自第2導光板6的出射光擴散，然後向第丄導光板4側透丨 過的擴散片20。 装根據本實施形態，當然可獲得與前述第i實施形態同 ‘的效果。而且’由於是利用擴散片2〇使從第2導光板6 射出的光擴散，因此不容易從第i導光板4的出射面n 側看見螢光燈（第3光源；以下相同）12。結果便可使從出 射面13射出的照明光的亮度更為均一化，並提升照明品 質。 [第4實施形態] 314883 13 1293709 本貫施形態是在前述第3實施形態的面光源裝置2當 2於擴散片2〇的表面形成光擴散圖案2丨，以調整來自 第2導光板6的出射光分布的樣態（參照第7圖）。 第8圖⑷是本實施形態之面光源裝置所採用的擴散片 的外觀斜視圖，第8_)是展開該擴散片後的俯視圖。 如這些圖式所示，本實施形態是在前述第3實施形態 、光源袭置2當中，於擴散片2〇白勺表面形成光擴散圖案 21’以调整來自第2導光板6的出射光分布(參照第7圖)。 J用P刷形成在擴散片2〇之表面的光擴散圖案2丨是 在螢光燈12的正上方形成最為緊密的形成密度，並且隨著 從勞光燈12正上方遠離使形成密度越為稀疏。此外，本實 知化I、田中’光擴散圖案2 i的各構成要素U是圓形。另 :安各構成要素22的面積是由大逐漸變小，藉此使光擴散 :案Μ的密度隨著從登光燈12正上方遠離，由密變疏而 寺級化（麥照第7圖）。 根據這種構成，從第i導光板4的出射面13側較不容 易看見第2導光板6側的螢光燈12，且可調整從第 板Μ則朝向第【導光板4 ]出射光分布。因此，可調等 來自第1導光板4的屮鼾伞八 正 錢4的出射先分布’且可使來自帛i導光板 4的出射光的亮度更為均—化（參照第7圖）。 此外’本實施形態是例示出在擴散片2〇的外 光擴散圖案21的樣態，#亦$ / ^ 取 〜仁亦可在擴散片2(3的内表面（外表 面的相反側之面）形成光擴散圖案21。 [第5實施形態] 314883 14 1293709 ,弟图疋本貝施形態所使用的導光板。亦即，本實施 二疋在别述第1實施形態（參照第1圖至第3圖）所示的 第 2、首* V光板6的出射面10形成第8圖（b)所示的光擴散圖 ^ 。由此即可省略第4實施形態所使用的擴散片20之 配置。 沒如第9圖所示，形成在第2導光板6之出射面16的光 擴散圖案21是隨著從螢光燈12正上方遠離，使形成密度 由在、變疏。因此，本實施形態的面光源裝置2可獲得與前鲁 ^第4實施形態同樣的效果。而且，本實施形態的面光源 破置2不需要配置於第2導光板6與第1導光板4之間的 擴散片20。 因此’比起前述第4實施形態的面光源裝置2，可減 少零件數目，且可謀求產品價格的低廉化。 此外’第9圖是例示出在第2導光板6的出射面i 6 形成光擴散圖案2 1的樣態，但亦可將光擴散圖案2丨形成 在第1導光板4的背面5側。而且，亦可在第2導光板6鲁 與第1導光板4之相對向的兩面5、丨6形成光擴散圖案2 1。 另外’亦可將光擴散圖案2丨形成在第2導光板6之光源收 容凹處1 7的内表面（參照第1圖至第3圖）。 [第6實施形態] 第1 〇圖是第6實施形態之圖像顯示裝置1所使用的面 光源裝置2。本實施形態是使第2導光板6的出射面16及 第1導光板4的背面5(相互重疊的兩面）形成梨面等的粗面 2 3，使從第2導光板6射出的光以及射入第1導光板4的 15 314883 1293709 光，散。藉此，從第丨導光板4的出射面13側就不容易看 見第2導光板6側的螢光燈12。且可謀求來自第i導光板 4的出射光的亮度均一化。 在此，第2導光板6的出射面！ 6以及第i導光板4 的背面5的粗面化可採用過去眾所週知的手法。例如，可 使模具的表面形成粗面，並且在射出成形時將其轉寫。另 外，亦可採用藉由喷砂處理或蝕刻等直接使第1及第2導 光板4、6之表面粗面化的手法。本實施形態亦可獲得與前❿ 述第5實施形態同樣的效果。 此外’本實施形態是例示出在第2導光板6的出射面 16以及第！導光板4的背面5兩面16、5形成粗面23的 樣態’但亦可形成在出射面16及背面5任何一方。另外， 亦可如第11圖所示，在第2導光板6之光源收容凹處17 的内表面形成粗面23。 [第7實施形態] 第1 2圖是第7實施形態之圖像顯示裝置1所使用的面馨 光源裳置2。如該圖所示，本實施形態是在前述第1實施 形態當中，於第2導光板6之光源收容凹處1 7的内側又配 置有燈光擴散片24。此燈光擴散片24是用來使螢光燈1 2 的光擴散而射入第2導光板6。 本實施形態當然可獲得與前述第1實施形態同樣的效 果。而且，螢光燈1 2的光是藉由燈光擴散片24擴散之後 射入第2導光板6，因此從第1導光板4的出射面13側不 容易看見螢光燈1 2。結果便可使從第1導光板4之出射面 16 314883 Ϊ293709 射出的…、明光免度更為均一化，並提升照明品質。 此外，根據本實施形態，燈光擴散片24的尺寸可以比 … 配置於兩導光板4、6之重疊面5、16的擴散片2〇的尺寸·, ]因此比起第3實施形態更可實現低成本化、輕量化（參 照第7圖及第12圖）。 · (第7實施形態的第1變形例） 在此，亦可如第！ 3圖所示，在燈光擴散片24的内側 表面，亚且在螢光燈12的正上方附近配置用來使光反射的_ · ^射構件（光反射片或光反射性塗料等）25。在該情況下， :P方止來自螢光燈i 2的光筆直朝上方射出。結果，從第i 導光板4的出射面13側就不容易看見螢光燈i2。如上述 構士時，當然可獲得與第7實施形態同樣的效果，且可使 ，第1導光板4射出的照明光更為均質化。此外，如前述 弟12圖所示，反射構件25亦可配置在燈光擴散片24的外 · 側表面，並且配置在螢光燈12的正上方附近。 (第7實施形態的第2變形例） φ 另外，亦可如第14圖所示，在燈光擴散片24的外表 面形成光擴散圖案26。在此，光擴散圖案26與形成在前 述第4實施形態之擴散片2〇的光擴散圖案21同樣（參照第 8圖），使形成密度在螢光燈12的正上方形成最為緊密， 隨著從螢光燈12正上方遠離，使形成密度越為稀疏。 * 如上述構成時，從第丨導光板4的出射面13側就不容 · 易看見螢光燈12,且可對於射入第2導光板6之來自螢光 燈12的光的分布進行調整。結果便可調整來自第I導光板 314883 17 1293709 4的出射光分布，且可實現來自第1導光板4的出射光亮 度的更均一化。 此外，本變形例是例示出在燈光擴散片24的外側表面 形成光擴散圖案26的樣態。但是亦可在燈光擴散片24的 内側表面形成光擴散圖案26，或是亦可在第2導光板6之 光源收容凹處1 7的内表面形成光擴散圖案26，以取代之。 [第8實施形態] 第1 5圖是第8實施形態之圖像顯示裝置1所使用的面_ 光源装置2。如該圖所示，在反射片3的上面（與第2導光 板ό之背面相對向的面）28形成有光吸收圖案27。光吸收 圖案27在對應於螢光燈12之部分（螢光燈12的正下方附 ^ )的^/成孩度最為緊密，離該處越遠形成密度越為稀疏。 $吸收圖案27是由使用光吸收性墨水而形成的大致圓形 多數個光吸收要素30所構成，並且藉由改變其面積，使形 成密度具有梯度（等級）。 [其他實施形態] _ 此外，上述各實施形態當中，亦可在第丨導光板的出 射面側利用透明的導電性樹脂印刷透明電極。此透明電極 具有:去除從螢光燈發出的高頻雜訊，以防止液晶顯示面 板因南頻雜訊所導致的圖像混亂。 :且’上述各實施形態當中，亦可在第1導光板4及 或第2 2板6之至少一方内部混入折射率與第1導光板4 U 2導光板6之折射率不同的材料所構成的微粒子。 另外，上述各實施形態是使用螢光燈丨〇、丨2作為第1 314883 18 1293709 至第3光源，但亦可並列複數個發光二極體（led)，並將 此複數個LED作為各光源。(Object of the Invention) As described above, the second conventional example and the third conventional example are easier to achieve miniaturization (thinning) than the conventional example, but it is not possible to fully cope with the recent reduction in power consumption. demand. Accordingly, an object of the present invention is to provide a surface light source device capable of avoiding a decrease in brightness of emitted light and a reduction in power consumption, an image display device using the surface light source device, and a guide plate assembly used in the device. Body (combination). (Technical means for solving the problem) The surface light source device of the present invention has a second light guide plate and a second light guide plate. Here, the first light guide plate has two side faces (human faces) on the opposite sides, and a second light source and a second light source are disposed in the vicinity of each of the side faces (incidence faces). The light from the first and second light sources is introduced into the light guide plate through the both side faces, and then emitted from the exit surface as planar illumination light. Further, a light guide plate engagement recess is formed on the back surface of the first light guide plate such that a substantially central portion between the i-th side surface and the second side surface of the first light guide plate is the thinnest. The exit surface side of the second light guide plate has a shape corresponding to the back side of the first light guide plate, and the second light guide plate is housed in the light guide plate bayonet such that the exit surface side thereof is close to the back side of the i-th guide wire. $. Further, a light source housing recess is formed on the back surface of the second light guide plate, and a third light source is housed there. The image forming apparatus of the present invention is constituted by combining the above-described surface light source device and the illuminated member illuminated by the surface light source. 々f^古 may also be used in the light guide plate recess on the back surface of the first light guide plate to receive the second light guide plate used as the light guide plate assembly used in the surface light source device image display device. Embodiments] The embodiments of the present invention will be described in detail below with reference to the drawings. 314883 (Revision page) 7 !2937 〇 9 [First Embodiment] Figs. 1 to 5 are image display devices 1 according to the first embodiment of the present invention. First, Fig. 1 is an exploded perspective view of the image display device 1. In addition, Fig. 2 is a perspective view showing the appearance of the surface light source device 2 r used in the image display device 1 of Fig. 1 . Fig. 3 is a front view of the image display device 1 of Fig. 1. In addition, Fig. 4 is a view of the surface light source device 2 viewed from the direction A of Fig. 3. 5 is a rear view of the surface light source device 2 after removing the reflection sheet 3 of the surface light source device 2 shown in FIG. 3 (a Lu diagram viewed from the B direction of FIG. 3) (Image display device (Schematic configuration) In the drawings, the second light guide plate 6 is placed on the back surface 5 side of the first light guide plate 4 to form the light guide plate assembly 7. The i-th light guide plate 4 has a pair of side faces (incidence faces) on the opposite sides to each other. Further, a rod-shaped fluorescent lamp as a second light source is disposed in the vicinity of the side surface (incidence surface) 8a, and a rod-shaped fluorescent lamp as a second light source is disposed in the vicinity of the side surface (incidence surface) 8b. These are preferably fluorescent lamps of the same size, the same shape, and the same type, both of which are designated by the numeral 10. Further, in the center of the back surface 11 of the second light guide plate 6 (the lower surface side in the i-th image), a rod-shaped fluorescent lamp 2 as a third light source is disposed so as to be substantially parallel to the fluorescent lamps 10 and 10. status. The surface (the upper surface in Fig. 1) i 3 1 4 is disposed as a member to be illuminated, and the reflection is arranged so as to overlap with the liquid crystal display panel 14 so as to face the first light guide plate 4 The liquid crystal display panel is disposed at a distance of 3° with respect to the back sheet of the second light guide plate 6. Further, a diffusion sheet or a cymbal sheet or the like may be appropriately disposed as the light control member when the first light guide plate 4 314883 8 1293709 is viewed. As described above, in the present embodiment, the fluorescent lamp 丨〇, the 〇, i2, the 导1 light guide plate 4, and the second light guide plate 6 constitute the surface light source device 2 for illuminating the liquid crystal display panel 14 in a planar manner. Further, the liquid crystal display panel 14 can be clearly disposed by the surface light source. (Light Guide Plate Assembly) The light guide plate assembly 7 is composed of the first light guide plate 4 and the second light guide plate 6. Each of the light guide plates is made of PMMA (P〇lymethylmethac) rylate: polymethyl methacrylate, PC (p〇lyCarb〇nate polycarbonate), and cyclO〇lefin resin. Formed from materials. The first light guide plate 4 is gradually reduced in thickness from one of the pair of incident surfaces 8a and 8b toward the other, and the thickness of the first light guide plate 4 is thinned at a substantially central portion between the incident surfaces 8a and 8b. Form a smooth circular surface. The exit surface 13 is a flat surface. In other words, as shown in FIG. 3, the 'f1 light guide plate 4 has a bilaterally symmetrical shape with the center portion CL in the left-right direction as a boundary, and has a plate thickness gradually decreasing from the respective projections: 8a and 8b toward the central portion CL. Profile shape. Further, the sides and the sides of the moon are inclined obliquely upward. Therefore, the light of the fluorescent lamps 1 〇 and 1 传播 which propagate inside is more easily reflected by the back Φ 5 . As a result, the light can be emitted; the exit surface 13 is effectively emitted. ^The outer surface is formed into a circular arc shape by the moon surface 5, and the space for the light plate 6 to be accommodated on the back surface 5 side can be secured (guide: the second light guide plate 6 is the first light guide plate 6 and the rear surface 5 side of the cold light plate 4 is overlapped, / The upper surface (outlet surface) has a shape corresponding to the back surface 5 314883 9 1293709 of the first light guide plate 4, and is curved in a manner that the center is adjacent to the thickest layer of the CL. When the second light guide plate 6 is superposed on the second light guide plate 4, the U-side of the moon surface (lower surface) is a flat surface that is formed substantially parallel to the exit surface 13 of the first light guide plate 4. In other words, when the light guide plate assembly 7 is formed by superimposing the light guide plate 6 on the first light guide plate 4, the exit surface π of the first elastic plate 4 is substantially parallel to the rear surface 11 of the second light guide plate 6. Further, the back surface of the second light guide plate 6 is 11 and the light source housing recess 17 for collecting the fluorescent lamp 12 is formed at a substantially central portion in the left-right direction of Fig. 3. The light source housing recess 17 is a facing edge. The direction of the incident surfaces 8a and 8b of the first light guide plate 4 is extended, and the light of the f-light lamp 12 is efficiently incident on the second light guide plate 6, so that the cross section is made. In the light guide plate assembly 7 of the present embodiment, the emission surface 16 of the second light guide plate 6 is superimposed on the back surface 5 side of the i-th light guide plate 4, and is grouped as 3, The first 'light panel 6 is accommodated in the space 15 on the side of the back surface 5 of the light guide plate 4, and the thickness of the light incident plate assembly 7 on the side of the entrance surfaces 8a and 8b of the first light guide plate 4 is formed to be the thickness of the light guide plate assembly 7. By using the light guide plate assembly 7', the size of the surface light source device 2 can be increased. (Reflective sheet) The reflection sheet 3 is excellent in light reflectance such as white PET (polyethylene glycol terephthalate). The material is formed in a rectangular shape having substantially the same size as the back surface 11 of the second light guide plate 6. The reflection sheet 3 diffuses and reflects the light emitted from the back surface 11 of the second light guide plate 6 and returns to the second light guide plate. 6 internal, can effectively benefit 10 314883 1293709 with light from fluorescent lamps 10, 10, 12. (lamp reflector) lamp reflectors 18, 18 are light-reflective resin materials such as white PET, or Formed by a light-reflective metal material such as a stainless steel plate or an aluminum plate The upper end edges of the lamp reflectors 18 and 18 are engaged with the edge of the exit surface 13 of the first light guide plate 4 constituting the light guide plate assembly 7. The lower end edge is engaged with the lower end edge of the reflection sheet 3. The lamp reflectors 8 and 8 have a function of directing the light from the fluorescent lamps 10 and 10 toward the incident surfaces 8a and 8b. The effect (effect and effect of the present embodiment) is as in the above embodiment. The light traveling from the fluorescent lamp 12 is incident on the inside of the second light guide plate 6 after being incident on the inside of the second light guide plate 6 from the surface of the light source housing recess 17 of the second light guide plate 6. In this process, light having an incident angle of less than the critical angle with respect to the upper surface (emission surface) 16 is emitted from the exit surface 16 of the second light guide plate 6. This light is incident on the inside of the first light guide plate 4 from the side of the back surface 5 of the first light guide plate 4. In addition, the light emitted from the fluorescent lamps 10 and 1 is directly reflected by the lamp reflectors U and 18, and is incident into the i-th light guide plate 4 from the incident surface 仏 and 讣, and is emitted through the second light guide plate 6. The light from the fluorescent lamp I] is transmitted together inside the light guide plate 4 of the brother 1. In this process, the light T below the critical angle with respect to the incident angle of the exit surface 13 is emitted from the exit surface η to the outside. Then, the pupil emitted from the exit surface 13 illuminates the illumination member (liquid crystal display panel) 1* in a planar manner. Here, since the second light guide plate 6 is light that is introduced into the fluorescent lamp 12 from the back surface 11, it is less expensive than the light 314883 11 1293709, and the light utilization efficiency (direction) The emission efficiency of the first light guide plate 4 is high. In the event of a combination of a plurality of fluorescent lamps 10, it is not necessary to have the light absorbed by the adjacent naphthalene #, batch, nt ^ and 1 ,, and the first use of the fluorescent lamp 1 提升 can be improved. effectiveness. 6 The light guide lamp 12 disposed in the center portion in the width direction of the second light guide plate can be used to fill the dam of the lamps 10 and 10, which is difficult to reach, that is, the first light guide plate 4 The brightness of the emitted light in the vicinity of the first light guide plate 4 can be directly illuminated by the light emitted from the second guide 6, so that the light output efficiency of the light guide plate 4 is higher than that of the seventh light guide plate. The second example of this is more improved. In the figure of FIG. 18, the surface light source device using the light guide plate assembly 7 can be used with less heart, (fluorescent lamp 10, 1 〇, 12), and the same is true. Illumination light emission performance. In other words, in comparison with FIG. 18, each of the incident surfaces 8a and 8b is assigned a six-fifth ^A ^AA ^W, and a plurality of fireflies are arranged, and the second to third conventional examples are arranged. Power consumption will decrease. The surface of the first light guide plate 6 is accommodated in the north of the first light guide plate 4, and therefore the thickness of the light guide plate assembly 7 is the thickness of the first incident surface 8a, 8b side, and ' Anti-2: Large size. Therefore, the surface light source of the present embodiment is more suitable for miniaturization than the first example of the device (the second embodiment). Fig. 6 is a view showing the ft original clothes 2 used in the image display light source _ @ 0 S 1 of the second embodiment. / That is, the surface light source package i 2 has the center portion of the thinnest portion of the flute panel 1 left and right. The light panel 4 is divided into two parts: d and the first division piece 3] 4883 12 1293709 第 and the second divided piece 4 b) Composition. According to this configuration, since the second guide is bilaterally symmetrical, it is possible to form the i-th guide: the plate 4 only by the molding die. Therefore, according to the present embodiment, the same effects as those of the embodiment can be achieved, and the price of the young product can be lowered. In addition, in the surface light source device 2 of the present embodiment, it is preferable that a diffusing sheet (not shown) is disposed on the emitting surface 13 side of the ith light guiding y, and the light emitted from the first light guiding plate 4 is provided. Diffusion and transmission prevent the divided portion of the first plate 4 from being easily seen. [Third Embodiment] Fig. 7 is a plan source device 2 used for displaying an image display in the third embodiment. In the surface light source cleavage 2 of the present embodiment, between the back surface 5 of the i-th light guide plate 4 and the exit surface 16 of the second light guide plate 6, the emitted light from the second light guide plate 6 is diffused, and then the second light is diffused. The diffusion plate 20 is permeable to the side of the light guide plate 4. According to the present embodiment, it is a matter of course that the same effect as the above-described first embodiment can be obtained. In addition, since the light emitted from the second light guide plate 6 is diffused by the diffusion sheet 2, it is not easy to see the fluorescent lamp (third light source; the same applies hereinafter) 12 from the exit surface n side of the i-th light guide plate 4. As a result, the brightness of the illumination light emitted from the exit surface 13 can be more uniform and the illumination quality can be improved. [Fourth Embodiment] 314883 13 1293709 In the surface light source device 2 of the third embodiment, the light diffusion pattern 2 is formed on the surface of the diffusion sheet 2 to adjust the light guide plate 2 from the second light guide plate 6. The pattern of the outgoing light distribution (refer to Figure 7). Fig. 8 (4) is a perspective view showing the appearance of a diffusion sheet used in the surface light source device of the embodiment, and Fig. 8 is a plan view showing the diffusion sheet. As shown in the drawings, in the third embodiment, in the light source arrangement 2, the light diffusion pattern 21' is formed on the surface of the diffusion sheet 2 to adjust the light distribution from the second light guide plate 6. (Refer to Figure 7). The light diffusion pattern 2 formed on the surface of the diffusion sheet 2 by the P brush is formed to have the closest formation density directly above the fluorescent lamp 12, and the density is formed as it goes away from the front side of the work lamp 12. Sparse. Further, each of the constituent elements U of the presently known I and Tanaka's light diffusing pattern 2 i is circular. In addition, the area of the constituent elements 22 is gradually reduced from large to large, thereby diffusing the light: the density of the case is away from the top of the Deng Deng 12, and the temple is leveled by the density (Ma Yin 7th) Figure). According to this configuration, the fluorescent lamp 12 on the second light guide plate 6 side is less likely to be seen from the emission surface 13 side of the i-th light guide plate 4, and the light distribution from the first plate toward the [light guide plate 4] can be adjusted. . Therefore, the emission of the Umbrella 8 from the first light guide 4 can be adjusted first and the brightness of the light emitted from the illuminator 4 can be made more uniform (see Fig. 7). Further, the present embodiment is an example in which the external light diffusion pattern 21 of the diffusion sheet 2 is exemplified, and #亦 is also taken from the inner surface of the diffusion sheet 2 (the opposite side of the outer surface). The light-diffusion pattern 21 is formed. [Fifth Embodiment] 314883 14 1293709, a light guide plate used in the form of the present invention, that is, the second embodiment is described in the first embodiment (see FIG. 1 to The light-diffusing pattern shown in Fig. 8(b) is formed on the exit surface 10 of the second and first *V light plates 6 shown in Fig. 3). Thus, the diffusion sheet 20 used in the fourth embodiment can be omitted. As shown in Fig. 9, the light diffusion pattern 21 formed on the exit surface 16 of the second light guide plate 6 is separated from the front side of the fluorescent lamp 12, so that the formation density is reduced. The surface light source device 2 of the embodiment can obtain the same effects as those of the fourth embodiment. Further, the surface light source breaking 2 of the present embodiment does not need to be disposed between the second light guide plate 6 and the first light guide plate 4. Therefore, the number of parts can be reduced and the product can be obtained as compared with the surface light source device 2 of the fourth embodiment. In addition, in the ninth diagram, the light diffusion pattern 2 1 is formed on the exit surface i 6 of the second light guide plate 6, but the light diffusion pattern 2 亦可 may be formed on the first light guide plate 4 . The light diffusion pattern 21 may be formed on both sides 5 and 丨6 of the second light guide plate 6 and the first light guide plate 4. The light diffusion pattern 2 may be formed in the second light guide plate 6 and the first light guide plate 4. The inner surface of the light source housing recess 17 of the second light guide plate 6 (see FIGS. 1 to 3). [Embodiment 6] The first image is used in the image display device 1 of the sixth embodiment. In the present embodiment, the exit surface 16 of the second light guide plate 6 and the back surface 5 of the first light guide plate 4 (both surfaces overlapping each other) form a rough surface 2 such as a pear surface, and the second light guide plate is formed. The light emitted from the light and the 15 314883 1293709 incident on the first light guide plate 4 are scattered, whereby the fluorescent lamp 12 on the side of the second light guide plate 6 is not easily seen from the side of the exit surface 13 of the second light guide plate 4. Further, the brightness of the emitted light from the i-th light guide plate 4 can be made uniform. Here, the exit surface 6 of the second light guide plate 6 and the back surface 5 of the i-th light guide plate 4 are thick. The surface can be formed by a conventionally known method. For example, the surface of the mold can be formed into a rough surface, and it can be transferred during injection molding. Alternatively, the first and second portions can be directly used by sandblasting or etching. The surface of the light guide plates 4 and 6 is roughened. In the present embodiment, the same effects as those of the fifth embodiment of the present invention are obtained. The present embodiment is an example of the exit surface 16 of the second light guide plate 6 and The two sides 16 and 5 of the back surface 5 of the light guide plate 4 form a rough surface 23, but may be formed on either the exit surface 16 and the back surface 5. Alternatively, as shown in Fig. 11, the second light guide plate may be used. The inner surface of the light source housing recess 17 of 6 forms a rough surface 23. [Seventh embodiment] Fig. 1 is a face light source device 2 used in the image display device 1 of the seventh embodiment. As shown in the figure, in the first embodiment, the light diffusion sheet 24 is disposed inside the light source housing recess 17 of the second light guide plate 6. The light diffusion sheet 24 is for diffusing the light of the fluorescent lamp 12 and entering the second light guide plate 6. In the present embodiment, of course, the same effects as those of the first embodiment described above can be obtained. Further, since the light of the fluorescent lamp 12 is diffused by the light diffusion sheet 24 and is incident on the second light guide plate 6, the fluorescent lamp 12 is not easily seen from the exit surface 13 side of the first light guide plate 4. As a result, the light-emitting degree of the light emitted from the exit surface 16 314883 Ϊ 293709 of the first light guide plate 4 can be more uniform, and the illumination quality can be improved. Further, according to the present embodiment, the size of the light diffusion sheet 24 can be made larger than the size of the diffusion sheet 2〇 disposed on the overlapping surfaces 5 and 16 of the two light guide plates 4 and 6, and thus can be realized more than the third embodiment. Cost reduction and weight reduction (refer to Fig. 7 and Fig. 12). (First Modification of Seventh Embodiment) Here, as in the first! As shown in Fig. 3, on the inner side surface of the light-diffusing sheet 24, a light-reflecting member (light-reflecting sheet or light-reflective paint or the like) 25 for reflecting light is disposed in the vicinity of the fluorescent lamp 12. In this case, the :P side stops the light pen from the fluorescent lamp i 2 and directly emits upward. As a result, the fluorescent lamp i2 is not easily seen from the side of the exit surface 13 of the i-th light guide plate 4. In the case of the above-described structure, it is of course possible to obtain the same effects as those of the seventh embodiment, and it is possible to make the illumination light emitted from the first light guide plate 4 more uniform. Further, as shown in the aforementioned Fig. 12, the reflection member 25 may be disposed on the outer side surface of the light diffusion sheet 24, and disposed near the upper side of the fluorescent lamp 12. (Second Modification of Seventh Embodiment) φ Further, as shown in Fig. 14, a light diffusion pattern 26 may be formed on the outer surface of the light diffusion sheet 24. Here, the light diffusion pattern 26 is formed in the same manner as the light diffusion pattern 21 formed in the diffusion sheet 2 of the fourth embodiment (see FIG. 8), so that the formation density is formed most directly above the fluorescent lamp 12, with Moving away from the top of the fluorescent lamp 12, the density of formation is more sparse. * In the above configuration, the fluorescent lamp 12 is not easily seen from the side of the exit surface 13 of the second light guide plate 4, and the distribution of light from the fluorescent lamp 12 incident on the second light guide plate 6 can be adjusted. As a result, the outgoing light distribution from the first light guide plate 314883 17 1293709 4 can be adjusted, and the uniformity of the emitted light from the first light guide plate 4 can be more uniform. Further, the present modification is an example in which the light diffusion pattern 26 is formed on the outer surface of the light diffusion sheet 24. However, the light diffusion pattern 26 may be formed on the inner surface of the light diffusion sheet 24, or the light diffusion pattern 26 may be formed on the inner surface of the light source housing recess 17 of the second light guide plate 6 instead. [Embodiment 8] Fig. 15 is a surface light source device 2 used in the image display device 1 of the eighth embodiment. As shown in the figure, a light absorbing pattern 27 is formed on the upper surface of the reflection sheet 3 (the surface facing the back surface of the second light guide plate )) 28. The light absorbing pattern 27 has the closest degree to the portion corresponding to the fluorescent lamp 12 (attached directly below the fluorescent lamp 12), and the farther away from the portion, the density becomes more sparse. The absorbing pattern 27 is composed of a substantially circular plurality of light absorbing elements 30 formed using a light absorbing ink, and has a gradient (gradation) in the density of formation by changing its area. [Other Embodiments] Further, in each of the above embodiments, the transparent electrode may be printed on the emission surface side of the second light guide plate with a transparent conductive resin. The transparent electrode has the function of removing high frequency noise emitted from the fluorescent lamp to prevent image confusion caused by the south frequency noise of the liquid crystal display panel. In the above-described respective embodiments, a material having a refractive index different from that of the first light guide plate 4 U 2 light guide plate 6 may be mixed in at least one of the first light guide plate 4 and the second light plate 6 . Microparticles. Further, in each of the above embodiments, the fluorescent lamps 丨 and 丨2 are used as the first 314883 18 1293709 to the third light source, but a plurality of light emitting diodes (led) may be arranged in parallel, and the plurality of LEDs may be used as the respective light sources. .
[發明之效果J 如以上所說明，根據本發明，由於是將第2導光板收 容在第1導光板之背面的導光板卡合凹處，因此可謀求面 光源裝置以及具備此面光源裝置的圖像顯示裝置的小型 化、輕量化。而且，不口是产笛彳戈丄4 y r ^ /、疋攸弟1绔光板之相對向的兩側 面側導入第1及笫2伞、、盾 先，原的先，而是在從第2導光板的背讀 面V入來自弟3光源的光 入# M ? m 傻攸第1導光板的背面側導 伙弟2 v先板之出射面 ®的先，因此可有效利用第1 先源至弟3光源的光。結 亮的面照明。 ……力的光源實現明 【圖式簡單說明】 斜視=圖是本發明第1實施形態之圖像顯示裝置的分解 視圖 弟2圖疋第1實施形態所採用的面光源裳置的外觀斜孀 圖 第3圖是第1實施形態所採 用的面光源裝置的前視 第4圖是在第3圖中從a 裴置的俯視圖。 方向觀看的圖 且是面光源 看的圖，且是去除反 裝置的外觀斜視圖。 射 第5圖是在第3圖中從B方向觀 片後從背面觀看面光源裝置的圖。 第6圖是第2實施形態之面光源 314883 19 1293709 第7圖是第3實施形態之面光源裝置的前視圖。 第8圖（a)是第4實施形態之面光源裝置所採用的擴散 片的外觀斜視圖，（b)是展開該擴散片後的俯視圖。 第9圖是第5實施形態之面光源梦w 衣置所採用的第2導 光板的外觀斜視圖。 第1 〇圖是第6實施形態之面光、、周姑亜 九源裝置的前視圖。 第11圖是第6實施形態之變形例沾 W的面光源裝置的前視 圖。 第12圖是第7實施形態之面光 衣罝的刖視圖。 第1 3圖是第7實施形態之第1蠻 又形例所使用的燈光揭 散片的如視圖。 變形例所使用的燈光擴 藏裝置的部分分解斜視 第14圖是第7實施形態之第2 散片的外觀斜視圖。 第1 5圖是第8實施形態之面光 圖0 第1 ό圖是第1習知例的面光源挺 ^ 原裝置的前視圖。 弟1 7圖是第2習知例的面光源奘 Η 展置的前視圖。 弟1 8圖疋弟3習知例的面光源缺 愿衣置的前視圖。 1、60、64圖像顯示裝置 3 反射片 4a、4b分割片 6 第2導光板 8a、8b入射面（側面） 2 N 5 4、5 6 6、61面光源裝置 4 楚 # 1導光板 5' 11 ' 63 背面 7 道 ¥光板組裝體 314883 20 1293709 10 螢 光燈（第1 光源/第2 光源） 12 螢 光燈（第3 光源） 13、16 、52、 、5 8出射面 14、 53 液 晶顯不面板（被照明 構件） 15 空 間（導光板收容凹處） 17 光源 收容凹處 18 燈 管反射器 20 ^ 24 、50 : 擴散板（片） 21、 26 光: 擔散圖案 22 構成 要素 23 粗 面 25 反射 構件 27 光 吸收圖案 28 上面 30 光 吸收要素 51 螢光 燈 57、 62 導 光板 21 314883[Effects of the Invention] As described above, according to the present invention, since the second light guide plate is housed in the light guide plate engagement recess of the back surface of the first light guide plate, the surface light source device and the surface light source device can be provided. The image display device is reduced in size and weight. Moreover, it is not the same as the two sides of the opposite side of the 彳 彳 彳 丄 丄 丄 丄 疋攸 疋攸 疋攸 疋攸 疋攸 疋攸 疋攸 疋攸 疋攸 疋攸 疋攸 疋攸 疋攸 丄 丄 丄 丄 丄 丄 丄 丄 丄 丄 丄 丄 丄 丄 丄 丄 丄 丄 丄The back-reading surface V of the light guide plate enters the light from the light source of the 3rd light source into the #M?m silly, and the first side of the first light guide plate of the first light guide plate is the first of the exit surface of the first board, so the first source can be effectively utilized. To the light of the 3 light source. Bright surface illumination. ...................................................................................................................................................................................................................................................... Fig. 3 is a front view of the surface light source device used in the first embodiment, and Fig. 4 is a plan view taken from a in Fig. 3; The view in the direction of the view is a view of the surface light source, and is an oblique view of the appearance of the removal device. Fig. 5 is a view of the surface light source device viewed from the back side after viewing from the B direction in Fig. 3. Fig. 6 is a front surface light source of the second embodiment. 314883 19 1293709 Fig. 7 is a front elevational view of the surface light source device of the third embodiment. Fig. 8(a) is a perspective view showing the appearance of a diffusion sheet used in the surface light source device of the fourth embodiment, and Fig. 8(b) is a plan view showing the diffusion sheet. Fig. 9 is a perspective view showing the appearance of a second light guide plate used in the surface light source of the fifth embodiment. Fig. 1 is a front view of the surface light of the sixth embodiment and the Zhouguyi Jiuyuan device. Fig. 11 is a front elevational view showing a surface light source device according to a modification of the sixth embodiment. Fig. 12 is a front view of the vestibule of the seventh embodiment. Fig. 3 is a view showing a light-emitting sheet used in the first example of the seventh embodiment. A partially exploded perspective of the light-expanding device used in the modification. Fig. 14 is a perspective view showing the appearance of the second fragment of the seventh embodiment. Fig. 15 is a front view of the eighth embodiment. Fig. 1 is a front view of the surface light source normalizing device of the first conventional example. The brother 1 7 is a front view of the surface light source 奘 展 of the second conventional example. Brother 1 8 Figure 3 The front view of the face light source lacking the clothing. 1, 60, 64 image display device 3 reflective sheet 4a, 4b split sheet 6 second light guide plate 8a, 8b incident surface (side) 2 N 5 4, 5 6 6 , 61 surface light source device 4 Chu # 1 light guide plate 5 ' 11 ' 63 Back 7-way light board assembly 314883 20 1293709 10 Fluorescent light (1st light source / 2nd light source) 12 Fluorescent light (3rd light source) 13, 16, 52, 5 8 Exit surface 14, 53 LCD panel (illuminated member) 15 Space (light guide housing recess) 17 Light source housing recess 18 Lamp reflector 20 ^ 24, 50 : Diffuser (plate) 21, 26 Light: Pattern 2 Component 23 rough surface 25 reflection member 27 light absorption pattern 28 upper surface 30 light absorbing element 51 fluorescent lamp 57, 62 light guide plate 21 314883