200817793 九、發明說明： 【發明所屬之技術領域】 本發明是關於一種邊緣光方式（edge-light type)的面光 源元件、使用於其之光控制部件及使用其之畫像顯示裝置 〇 【先前技術】 在使用於畫像顯示裝置的面光源元件，雖有邊緣光方 式及正下方式（direct type)之兩種方式，但邊緣光方式的面 光源元件係線狀光源位於導光板的側面，因此與正下方式 之面光源元件相比較，具備有效地謀求薄型化之特徵，故 廣泛地使用作爲攜帶用筆記型個人電腦或監視器等之顯示 部。 在此種邊緣光方式的面光源元件，係使用以透明樹脂 等製作而具有通常爲矩形狀之主面之導光板。此導光板在 屬於主面之一方的出射面及屬於與此出射面對向之另一主 面的底面之間，具有配置線狀光源或點狀光源等之一次光 源的入射端面。 從一次光源射出的光，經過：自導光板的入射端面射 入導光板內部，而導光於導光板內部，藉由形成在導光板 之底面的散亂點（白色點）而散亂，或者一度從導光板之底 面射出，藉由對向於底面且配置反射面的反射片而散亂， 再度射入導光板等之過程’從出射面朝向液晶顯示元件部 射出。 將散亂點（白色點）印刷於導光板之底面的印刷點方式 200817793 之導光板係藉由調整此點（dot)之大小、密度等，以使視認 方向的亮度分布變成均勻的方式來予以調整。藉此，從一 次光源射出的光從入射端面射入導光板，此入射光一面在 導光板內部傳導，一面從出射面朝向液晶顯示元件部射出 0 使用此種印刷點方式的導光板之面光源元件係利用在 散亂點之光散亂，因此從導光板出射的光顯示擴散爲廣角 度的配光分布，而無法充分獲得作爲面光源元件上很重要 的向正面方向之配向及亮度。因而，爲了使從導光板出射 的光聚光於正面方向以謀求高亮度化，而使用多片擴散片 ，除了擴散片之外，更使用稜鏡片（指向性片）。 擴散片係利用將已分散擴散性微粒的液體塗布在片的 單面或雙面，已使微粒分散的樹脂成型爲片狀而製作的內 部或表面已分散有擴散性微粒的片，使入射至片的光藉由 已隨機分散之擴散性微粒而進行擴散。 例如，當觀察表面塗布型之擴散片的表面時，微觀上 塗布有擴散性微粒之區域及未塗布有擴散性微粒的平坦面 係混雜在一起。此種擴散片被發現，對於從擴散片之正面 方向入射的光之散亂效果小，而對於以大的入射角入射於 正面方向的光則有大的散亂效果。 從印刷點方式之導光板之出射面射出的光，在所有的 方向大致都一*樣地分布。將一片上述擴散片載置於該導光 板之上時，射出於正面方向附近的光保持原狀地透過’相 對於正面方向以40。以上射出的光之一部分，因爲會由於該 200817793 擴散片而偏向於正面方向，故正面方向之亮 〇 然而，擴散片之微粒將光朝隨機的方向 擴散片將入射的光功能性分配於目的方向之 ，不易有效地提高朝所希望的正面方向之出 即使爲了期待更朝正面方向之偏向而重 散片時，從擴散片出射的光之配光分布卻更 因此無益於視角特性之改善，且招致亮度之 另一方面，稜鏡片可更有效地提高正面 稜鏡片之出射光，一般爲如第14圖所示，宅 急遽地降低，在50°以上產生亮度高的區域， 爲較佳畫像品質、能源效率降低等的問題。 因此，在配置稜鏡片之情況，爲了使這 布變更爲隨著朝斜方向成爲廣角而單調地亮 分布，及爲了防止稜鏡片受傷，必須使擴散 片之出射面側。因此，在配置稜鏡片之情況 因而招致亮度之降低，生產效率之降低及成 著這些光學片之零件點數之增加而有元件之 問題。因此，雖然這些薄片使用100〜300 // m 卻易起皺而成爲在組合製程之不良品發生之 鏡片之起皺，使面光源元件之照明品質顯著 又，在配置棱鏡片之情況，亦有棱鏡之 受傷而成爲外觀品質降低的原因的問題，雖 問題而開發將頂部變更爲曲面的稜鏡片，但 度可增加若干 擴散，故此種 能力爲低。即 光比率。 疊使用多片擴 成爲等方性， 降低。 亮度。但是， E 30°附近亮度 因此有無法成 些不自然的分 度降低的自然 片配置在棱鏡 須要擴散片， 本提高。更隨 薄型化不易之 之薄型者，但 原因，尤其棱 地降低。 尖銳頂部容易 然爲了解決此 此情況會降低 200817793 提高正面亮度之功能。 另一方面，近年來在高亮度化過程爲了避 點數之增加，而提案有藉由在導光板之出射面 射面的底面等形成稜鏡片，使從出射面射出的 方向（例如，參照專利文獻1〜4)。 例如，在專利文獻1中提出一種導光板， 於入射端面爲直角或傾斜的凸條（或凹條之溝5 射面，在對向於出射面的底面配置印刷點或凹 種導光板中，藉由使導入於導光板內的光被導 深處，可省略以相對於入射端面爲使溝列形成 的方式所設置的下側安裝用之稜鏡片（指向性少 照此專利文獻1，係提出藉由使上述之凸條（或[ 作成交叉，可省略2片稜鏡片。 又，在專利文獻2、3中，揭示有稜鏡光學 導光板。在此種稜鏡光學元件一體型導光板中 及底面分別具有交叉方向的V字狀之溝列。藉 射端面射入的光取入於底面，而使其反射光有 出射面方向。又，經由形成於出射面的稜鏡片 射出時，在垂直於入射端面之方向射入的入射 出射面或與其相近的角度射出。 又，在專利文獻4中，揭示有一種導光板 別以預定之間距交互排列的凸條及凹狀之圖案 及底面互相地直行而配置，根據此種導光板時 種極度地省略稜鏡片等之指向性片的使用，且 免此種零件 、對向於出 光朝向視認 其係使相對 ϋ )配置於出 凸點。在此 至導光板的 於直角方向 f )。又，依 3條之溝列） 元件一體型 ，在出射面 此，將從入 效地反射到 而從出射面 光能以垂直 ，其係使分 ，在出射面 ，可提供一 在不減少筆 200817793 直方向的亮度之情況可確保視角的導光板。 專利文獻1 :日本專利申請公開平9-61631號公報（第 6,8圖及段落003 8) 專利文獻2:日本專利申請公開平10-282342號公報 專利文獻3 :日本專利申請公開2003 - 1 1 4432號公報 專利文獻 4 : WO/2006/0 1 3969 【發明内容】、 【發明欲解決之課題】 然而’根據專利文獻1所記載的導光板時，雖然揭示 藉由使凸條或凹條交叉而形成，可省略2片指向性片之使 用，但是產生無法避免某種程度之發散光的課題。 又，在專利文獻2或3所記載的稜鏡光學元件一體型 導光板中，在出射面及底面形成的凸條或凹條，係頂角爲 銳角之V字條的溝列。在使用具有此種V字條之溝列的稜 鏡光學元件一體型導光板之邊緣光方式的面光源元件中， 除了光不易朝筆直方向（法線方向）射出之外，更有視角狹 窄的課題。又，視情況而定，由於視認角度而使亮度之明 暗爲顯著，因此有不僅在表面眩光很顯著，而且當從斜向 視認矩形狀之導光板的角落部時會看到暗線狀之線而使畫 面品質降低的課題。因而，在此種稜鏡光學元件一體導光 板中，需要使用1片至2片之擴散片，以一面確保筆直方 向的亮度一面擴大視角’因此有全體之亮度減少的課題。 又，根據專利文獻4所記載的導光板時，在出射面或 底面之至少一方的面交互地配置梯形形狀之凸條及梯形形 200817793 狀之凹條，雖然提高筆直方向的亮度且可某種程度確保視 角，但是仍期望可更進一步提高。 因而，本發明之目的在提供一種面光源元件及畫像顯 示裝置，可提高正面方向的亮度’且可謀求視角之增大。 又，本發明之另一目的在提供使用於此種面光源元件的光 控制部件。 【解決課題之辦法】 在本發明中，藉由在出射面及與出射面對向的底面具 有分別正交之凸條的圖案之導光板、及在出射面具有特定 之壟狀凸部的光控制片之組合，而解決上述課題。 即，本發明之面光源元件，係將至少1個線狀光源配 置在導光板之至少1個側面的邊緣光方式之面光源元件， 其特徵爲：該導光板具有出射面、對向於該出射面的底面 、及使從上述線狀光源射出的光射入之入射端面，在上述 導光板的底面側具備反射光的反射手段，在上述導光板的 出射面側具備有控制從上述導光板射出的光之方向的光控 制部件，將以X軸、及正交於X軸之γ軸構成的X - γ平面 之法線作爲z軸，上述線狀光源係配置成平行於X軸，上 述反射手段、上述導光板、及上述光控制部件係配置成平 行於上述X-Y平面而朝Z軸方向依上述反射手段、上述導 光板、及上述光控制部件之順序構成，上述導光板之入射 端面係平行於X軸，在上述出射面及上述底面形成凸條之 圖案，形成於上述出射面之圖案係平行於Y軸，形成於上 述底面之圖案係平行於X軸，上述光控制部件係在光主要 -10- 200817793 出射之側形成平行於X軸之多個壟狀之凸部，在平行於以 Y軸及Z軸構成的Y-Z平面之上述凸部的截面之輪廓線具 有至少包含頂部之曲線部，該輪廓線之切線和Y軸交叉之 傾角0在以上述凸部之頂點爲中心朝兩方向單調地增加之 範圍內，分別滿足下列之公式： 0.450 maxS 0 0.75(9 max 0.25p^ I Ymaxl 其中， 0 max :從輪廓線之頂點單調增加之0的最大値 Ymax :從輪廓線之頂點單調增加之0取爲0 max時之 Y軸方向的位置 Y?= Ymax/2 0 ’ ：在Y軸方向的位置爲Y ’之位置的輪廓線之切線 的相對於Υ軸之傾角 Ρ :輪廓線之與Υ軸平行之方向的寬度 又，本發明之上述面光源元件係如申請專利範圍第1 項之面光源兀件’其特徵爲上述光控制部件之上述凸部之 Υ-Ζ平面的截面形狀，係由將橢圓之長軸的一端作爲頂點 之橢圓的一部分形成的局部橢圓形狀，上述局部橢圓形狀 的切線相對於Υ軸的傾角之最大値係從6 0度至8 0度之範 圍內，且高度h對上述局部橢圓形狀之與γ軸平行的方向 之寬度P的比之所§胃局寬比（aspect ratio)係從0.39至0.53 之範圍內。 又，本發明之上述面光源元件係如申請專利範圍第1 -11 - 200817793 項之面光源元件，其特徵爲在上述光控制部件之上述凸部 之Y-Z平面的截面形狀，係由包含拋物線之頂點的拋物線 之一部分形成的局部拋物線形狀，上述局部拋物線形狀的 切線對Y軸之傾角的最大値係從5 2度至6 2度之範圍內， 且高度h對上述局部拋物線形狀之與γ軸平行的方向之寬 度P的比之所謂高寬比係從0.32至0.47之範圍內。 又’本發明係上述之面光源元件，其特徵爲在上述導 光板之出射面側之上述圖案之以X軸與Z軸構成之X - Z平 面的截面，係形成具有與X軸平行之上底部及連結至該上 底部之2個斜邊部的梯形形狀之凸條，該梯形形狀之高度 係在1 // m〜1 0 0 // m之範圍內，斜邊部之對X軸的傾斜角爲 在15°〜70°之範圍內，上底部之寬度係在1/zin〜500 //rn之範 圍內’在上述導光板之底面的上述圖案之γ_Ζ平面的截面 ’係形成具有與Y軸平行之上底部及連結至該上底部之2 個斜邊部的梯形形狀之凸條，該梯形形狀之高度係在}从 m〜1 0 0 // m之範圍內，斜邊部之對γ軸的傾斜角爲在3 2.5。 〜45°之範圍內，上底部之寬度係在3/z m〜1600# m之範圍內 〇 又’本發明係使用於上述面光源元件的光控制部件。 又’本發明係一種畫像顯示裝置，其特徵爲：在上述 面光源元件之光控制部件的出射面側具備透過型顯示元件 【發明之效果】 依照本發明時，可提供一種面光源元件及畫像顯示裝 -12- 0 200817793 置，一面可提高正面方向的亮度，且一面可謀求視角之增 大。 【實施方式】 以下將說明用於實施本發明的最佳形態。此外，在以 下的圖式中，爲了說明方便起見，藉由任意變更各部之縱 橫的縮小尺寸的示意圖來說明。 首先，本發明之面光源元件10，如第1圖、第2圖所 示，係大致由下列構成的邊緣光方式之面光源元件：導光 板1，由透明樹脂等形成的平板狀（面板狀）之透明構造體； 一次光源4，配置於此導光板1之一側面；反射片5，配置 於導光板1之下面；及光控制片1 1，由配置於導光板1之 上面的透明樹脂等形成而作爲光控制部件。 在此種面光源元件10中，將X軸及正交於X軸之Y 軸構成的X_Y平面之法線作爲Z軸，導光板1具有平行於 X軸之入射端面8、平行於Χ-Υ平面之出射面6、及底面7 ，一次光源4係平行地配設於導光板1之入射端面8，從入 射端面8射入的光從導光板1之出射面6射出，透過光控 制片1 1朝Ζ軸方向射出。 光控制部件亦可支撐於導光板。藉此，不需要用以固 定光控制部件的機構，且因爲不必固定而不會有由於裝置 之熱等引起在光控制部件上產生對固定部之應力集中，故 可抑制破損或光控制部件的顯著變形。又，即使將光控制 部件作成薄型時亦能以導光板支撐，因此不易產生撓曲。 [導光板1之說明] -13- 200817793 本發明所使用的導光板，係使用於邊緣光方式的面光 源元件，藉由出射面之凸條及與出射面對向之底面的凸條 的圖案，而一面保持寬廣的視角特性，一面具有可獲得高 亮度之功能。 本發明所使用的導光板1，可由透光率高的透明樹脂 構成。此種透明樹脂方面，例如可廣泛採用甲基丙烯酸樹 脂、丙烯酸樹脂、聚碳酸酯樹脂、聚酯樹脂、環狀聚烯烴 樹脂等。 在本發明中，導光板1之一面係作爲出射面6，底面7 對向於此出射面6而配置。又，在此導光板1之至少一側 面配置一次光源4，此側面係作爲入射端面8。 在本發明中，雖然此入射端面 8，如圖示，只要有至 少一處即可，但是亦可爲多處，入射端面8爲一處之情況 ，在入射端面8以外之側面形成反射端面8a。 入射端面8爲二處之情況的典型例，如後述之實施例 所示，係在互相對向之面有作爲一次光源之線狀光源之例 ’反射端面形成於兩側面。二處之入射端面8必須滿足： 任一個需與形成於出射面6的圖案正交，與形成於底面7 之圖案平行的條件。 一次光源配設成朝向此入射端面8。此種一次光源爲 線狀光源時，雖可使用任何型式者，但是亦可爲所謂線狀 光源或由LED光源等之點狀光源多數排列而成爲線狀的光 源（線狀光源）。 本發明中，在導光板的出射面6及底面7之兩面以既 -14- 200817793 定間距形成的凸條2、9之圖案係互相正交而形成。此等凸 條2、9包含以下將欽述之梯形形狀之凸條2、9，亦可使用 與習知之面光源元件所使用的凸條2、9實質上相同或均等 者。 此等凸條2、9係形成截面突出的凸（突）部朝一方向延 伸。此等凸條之截面形狀可爲三角形、楔狀、其他之多角 形、波狀、或半橢圓狀等所希望之形狀。 在此，雖然形成於出射面6之凸條2可排列爲相同的 間距及形狀，但形成於底面7的凸條9亦可隨著遠離一次 光源而縮短間距排列，又，可隨著遠離光源而使凸條之高 度逐漸變高。又，亦可構成隨著遠離一次光源而形狀逐漸 相異。此種形狀逐漸相異的構成包含，例如，在截面具備 梯形狀之凸條之情況下，梯形之上底及/或下底之長度爲逐 漸相異之情況。在任何一種情況，係使利用底面7及反射 片5而折射的光從出射面6以所希望之強度射出用以控制 底面7之構造者，此等之調整可互相地加以組合或與其他 之調整手段倂用而進行。 在本發明之面光源元件1 0所具備的導光板1，在出射 面6及底面7具備的圖案係截面爲梯形形狀的凸條2、9時 ，在屬視認方向之正面亮度變成更高，且視角特性變成更 廣之點，係更佳之形態。 在此，所謂梯形形狀的凸條2、9是指從導光板朝表面 側突設成梯形形狀而向長邊方向延伸的突條。 例如，在第3圖所示之導光板1之表面，在其一表面 -15- 200817793 1 a以符號A、B、C及D作爲各頂點的截面爲梯形的凸條2 、9係和以符號A ’、B ’、C ’及D ’作爲各頂點的截面爲梯形 狀的凸條2 ’、9 ’間隔而配置。 而所謂本發明之梯形，如圖面所示，並不限定於嚴謹 意義的梯形。由後面將敘述的說明可了解，只要使平行於 X-Y平面而高度相異的平面之上底及下底將連結爲山形之 斜面加以挾持而連續的話，例如即使上底或下底與斜面之 連結部爲曲面狀亦無妨。具有此種曲面狀之連結部的梯形 形狀，因爲在成型上比較容易，不僅在生產上有利，且不 易引起連結部之破損而較佳。又，亦可使上底、下底之至 少一部分具有相對於X-Y平面之傾角，例如上底及下底係 將X軸方向作爲長邊方向的緩和的波狀，或可藉由具有微 細的凹凸而提高出光的均句性。該傾角之平均相對於X-Y 平面以不具有角度爲較佳。又該傾角爲1 0°以下的部分以佔 全體的5 0 %以上爲較佳。 又，使多個上底 2a、2a’，9a、9a’下底，各自互相在 同一 χ-γ平面內，不僅可有效地將光導出，而且可使導光 板的重心穩定。藉擠出成型等在工業上可使有利的連續生 產變爲容易，可達成實際應用上有用的作用效果。 其次，針對此種梯形之功能，以出射面6爲例將使用 第3圖來說明。雖使用「上底」、「下底」之用語，但其 並不意味係上下方向，係爲了說明。梯形的平行之對邊之 中，將短邊作爲「上底」、將長邊作爲「下底」而說明。 首先，在此第3圖中，設直線AD之長度（凸條2之下底的 -16- 200817793 寬度）爲W1，設直線BC之長度（凸條2之上底2a的寬度） 爲W2，設直線AD’之長度（凹條3之上底3a的寬度）爲W3 ，設凸條2之高度（或凹條3之深度）爲Η，將直線AD與直 線ΑΒ(傾斜面2b)所成的角度作爲al，將直線AD與直線 DC(傾斜面2c)所成的角度作爲a2，且將直線DD’之長度作 爲間距P。間距P係等於凸條2之下底的寬度（直線AD之 長度）W1與凹條3之上底3 a的寬度W 3的和，又等於凸條 2之上底2a的寬度（直線BC之長度）W2與凹條3之下底的 寬度（直線BC’之長度）的和。 在本發明之面光源元件所具備的導光板1之出射面6 中，將凸條2之截面形狀作成梯形，並在凸條2設成適宜 的寬度W2，藉此擔當使從入射端面8射入的光導向導光板 之中央的角色，而且可提高在從出射面6出射的亮度分佈 中正交於出射面6的筆直方向（法線方向）之亮度。 又，在本發明之面光源元件所具備的導光板1之出射 面6中，將凹條3之截面形狀作成梯形，並在凹條3設成 所希望的寬度W3，藉此與上述之W2同樣地擔當使從入射 端面8射入的光沿著Y軸方向傳導至導光板內部的角色， 而且可提高在從出射面6出射的亮度分佈中正交於出射面 6的筆直方向（法線方向）之亮度。 當此寬度W2太狹窄而使傾斜面2b、2c的貢獻變成太 大時，不易充分地發揮提高筆直方向的亮度之效果。 又，當此寬度W3太狹窄而使傾斜面2b、2c的貢獻變 成太大時，不易充分地發揮提高筆直方向的亮度之效果。 -17- 200817793 又，相對於此，將寬度W2及/或寬度W3相對傾斜面 2b、2c設定爲相對地太寬時，傾斜面2b、2c的貢獻相對地 變少。然後，雖然能謀求筆直方向的亮度之提高，但視角 變狹窄，而無法充分地滿足極度省略指向性片、且在不降 低筆直方向的亮度下足以確保視角的課題。 在本發明之面光源元件所具備的導光板1之出射面6 中，凸條2或凹條3之形狀及大小及間距P，係考慮與導 光板1之大小、面光源元件1 〇之顯示性能及規格等的關係 而決定。藉此，可適度地保持從導光板1之出射面6射出 的光之亮度，且可獲得適當的視角。 此種凸條2(或凹條3)之一般的高度H，係從1 // m〜100 // m的範圍內選擇，更佳的高度Η係5 // m〜50 // m，最佳的 局度Η係從10// m〜30// m的範圍內選擇。又，一*般的傾斜 角al及傾斜角a2分別自15°〜70°的範圍內選擇，更佳的傾 斜角al及傾斜角a2爲分別自15°〜60°的範圍內選擇。尤其 在重視視角特性的情況，最好在1 5 °〜3 5 °的範圍內選擇；在 重視亮度特性的情況，最好在3 5 °〜6 0 °的範圍內選擇。 又，一般之下底的寬度W1在10//m〜500//m的範圍內 選擇，更佳爲在15//m〜270/zm的範圍內選擇，最佳爲在 15// m〜180// m的範圍內選擇。 又，上底的寬度W2爲在1/zm〜500//m的範圍內選擇 ’更佳的寬度W2爲在l//m〜100//m的範圍內選擇，最佳 爲在5/zm〜5〇//m的範圍內選擇。 又，一般之寬度W3爲在0.1/zm〜500/zm的範圍內選 -18 - 200817793 擇，更佳的寬度W3爲在0.1//m〜300/zm的範圍內選擇， 最佳爲在l//m〜150//m的範圍內選擇。 本發明中，導光板1之出射面6由於寬度Wl、W2、 W3與間距P的關係，以具有保持特定之比率而形成的梯形 狀之圖案爲較佳。 即，本發明中，較佳在爲導光板1之出射面6，形成 於凹條3之上底的寬度W3對形成於此等凸條2之上底的 寬度W2的比（W3/W2)，以在0.01〜200的範圍內爲較佳，更 佳爲在0.02〜100的範圍內，最佳爲在〇.1〜1〇的範圍內。 又，（？-\¥2-，3)對（^¥2 + \\^3)的比，以在〇.〇4〜4 00的範圍 內較佳，更佳爲在0.2〜200的範圍內，最佳爲在0.3〜150的 範圍內。 在本發明之面光源元件所具備的導光板1之出射面6 中，使W 3對W 2的比保持於這些範圍內，藉以適度地保持 從導光板1之出射面6射出的光之亮度，且使爲了獲得適 當的視角的條件設定變成容易。 在此，當W3對W2的比爲在〇.1〜1〇的範圍內之時， 可謀求筆直方向之亮度的提高。又，當（P-W2-W3)對（W2 + W3) 的比在0 · 3〜1 5 0的範圍內時，可一方面抑制筆直方向之亮 度的降低，一方面增大視角特性。 另一方面.，在本發明之面光源元件所具備的導光板丄 之底面7，截面爲梯形狀的凸條9及凸條9 ’係將W 3設爲0 而互相接觸且平行於入射端面8排列。藉由逐漸調整此梯 形狀的凸條9之大小，可調整從出射面6射出的光之光量 -19- 200817793 分佈。 形成於此導光板1之底面7的梯形狀之凸條9的截面 形狀，較佳爲將傾斜角al及傾斜角a2設定在32.5°〜4 5°的 範圍內，更佳爲在35°〜45°的範圍內，最佳爲在37.5°〜42.5° 的範圍內。高度較佳爲設定在1 // m〜1〇〇 μ m的範圍內，更 佳爲在5//m〜50//m的範圍內，最佳爲在l〇//m〜20//m的 範圍內。上底部的寬度較佳爲設定在3// m〜1600// m的範 圍內，更佳爲在10//m〜800//m的範圍內，最佳爲在15// m〜3 5 0 // m的範圍內。下底部的寬度較佳爲設定在6 // m〜1800//m的範圍內，更佳爲在i5//m〜1000//m的範圍內 ，最佳爲在25/zm〜400//m的範圍內。 [光控制部件之說明] 本發明之光控制部件1 1具有：將來自導光板1的出射 光，擴大水平方向的視角，且將上下方向之視角聚焦而朝 向正面的功能。 本發明中，光控制部件1 1係，如第1圖所示，由透明 樹脂等形成片狀、薄膜狀、面板狀等之平板狀，在本體1 4 之一表面側（出射面）具有以既定之間距形成的特定之壟狀 凸部1 5。所謂此壟狀凸部1 5係平行於X軸而延伸的凸形 狀之圖案，且平行於Y -Z平面之截面的輪廓線1 5 a具有至 少包含頂部的曲線部。此壟狀凸部1 5係成爲在細長的直線 上隆起的形態。 在此，如第1圖之詳細所示，此輪廓線1 5 a之在Y-Z平 面之切線與Y軸所成的角度Θ，在以凸部之頂點作爲中心的 -20- 200817793 兩方向單調地增加之範圍，係滿足下列公式⑴及（π)。 0.45 Θ max ^ Θ 1 S〇.750max …公式（I) 0.25p S I Ymax | ···公式（η) 在此’ Ymax係爲從原點單調增加之θ取爲0 max時之 Y軸方向的位置（從原點到γ軸之距離），即在Ymax之輪廓 線1 5 a之切線的傾角爲0 m a X。又，0 ’係將Y ’設爲Y m a X 之1 /2的情況之在Y ’的位置之輪廓線1 5 a對γ軸的傾角，p 係輪廓線1 5 a與Y軸平行之方向的寬度（間距）。 從而，在輪廓線1 5 a有反曲點之情況，γ m a X係爲從原 點到反曲點之距離，在此位置之傾角係爲0 max。 在此，在公式（I)中，係意味著Y，爲Ymax之1/2之時 在Y ’的位置之輪廓線1 5 a對Y軸的傾角0，之取得形狀。 從而’在公式（I)中，係意味著取得在γ，爲Ymax之1/2 之時在Y ’的位置之輪廓線1 5 a對Y軸的傾角0 ’之形狀。 又，在公式（II)中，即使有反曲點之情況時，位置Ymax 顯示爲間距P之1 /4，即顯示經常位於自輪廓線1 5 a之單側 1 /2算起的外側。藉此，例如僅頂部形成圓形的光控制片（ 稜鏡片）不在此限。 此外，此圖係說明用圖，雖圖面上顯示反曲點而加以 說明，但是如後面將敘述之實施例般，亦可無此反曲點。 [作用之說明] 接著，將說明藉著採用在出射面及與出射面對向的底 面具有相互正交之凸條的圖案之導光板、及在該導光板的 出射面側、在其出射側具有特定之壟狀凸部的光控制片之 -21 - 200817793 組合，一方面提高正面方向之亮度，且一方面可確保視角 的原理。 [垂直（上下）方向之改善] 首先，自本發明之面光源元件所具備之導光板朝上下 方向（Y軸方向）出射之光的角度亮度分布係顯示在第6圖 。即，此第6圖是在第1圖中未具備以符號1 1所示之光控 制片的情況，從出射面6射出的出射光之角度分布圖。顯 示由導光板1射出的光爲朝與正面方向爲45°附近的出射成 分有較多的分布。 其次，第7圖是顯示相對於光控制片1 1之入射面1 1 a 的法線平行地射入之光1 2a的一部分之進行方向。在此第7 圖中，相對於光控制片1 1之入射面1 1 a的法線平行地入射 之光12a的一部分穿過入射面而在凸部曲面15a折射，如 以符號1 3 A所示，在正面方向附近射出。 其次，第8圖是顯示從相對於光控制片1 1之入射面 11a的法線傾斜地（45°附近）射入之光12b的一部分之進行 方向。在此第8圖中，從相對於光控制片1 1之入射面1 1 a 的法線傾斜地射入之光丨2b的一部分在入射面1 1 a及凸部 曲面1 5 a折射，如符號1 3 B所示，在正面方向附近射出， 其他一部分如符號丨3C所示，全反射再回到導光板1。 依此方式，根據本發明時，在上下方向（Y軸方向）之 45°附近擴散的從導光板丨射出的光係向正面方向被聚焦， 光板1向正面方向射出的光，由於保持向正面方向射 ’而與有效地提高亮度習習相關。依此方式，穿透光控 -22- 200817793 制片1 1之從本發明的面光源元件射出的光在上下方向（Υ 軸方向）之角度亮度分布係顯示於第9圖。 [水平方向之改善] 其次，從本發明之面光源元件所具備之導光板朝水平 方向（X軸方向）出射的光的角度亮度分布係顯示於第10圖 。從本發明之面光源元件所具備之導光板射出的光，係朝 正面方向射出之成分爲多的分布。 光控制片之凸部係平行於X軸方向配置，以X軸爲水 平方向而設置本發明之面光源元件之情況時，從導光板射 出的光，在光控制片之入射面及凸部曲面折射，水平方向 之角度亮度分布係相對於正面方向朝更分散的方向射出。 因此，當除了本發明的導光板之外、更在導光板之出射面 側配置本發明之光控制部件時，水平方向之視角會擴大， 可改善視角特性。第1 1圖是顯示自本發明之面光源元件出 射的光在水平方向的角度亮度分布。 艮Ρ，本發明所使用的導光板，係使用邊緣光方式的面 光源元件，藉由出射面之凸條及與出射面對向之底面的凸 條之圖案，具有用以一方面保持廣視角特性，一方面獲得 高売度之功能。 又，支撐於導光板的光控制片在出射面具有凸部，導 光板之至少一個入射端面平行於X軸設置之情況，該光控 制片之凸部配置成平行於X軸，當將X軸方向設爲水平方 向，將與X軸正交的Υ軸方向設爲上下方向時，在來自導 光板的出射光’具有將水平方向的視角擴大’且將上下方 -23- 200817793 向之視角聚焦而朝向正面的功能。 又，藉由使用具有梯形狀的凸部之導光板及光控制片 ，可降低光之吸收或朝不要之方向的出光，故光的利用效 率提高，可實現省能源化。 本發明之面光源元件所具備的導光板，係使從一次光 源射入的光，藉由配置於與出射面對向之底面的凸條的圖 案，進行朝出射面方向之方向轉換及控制從出射面射出的 光量，藉由出射面的凸條的圖案，而控制光之出光分布。 光控制片的凸部，由於可將導光板的出射光有效率地 更朝向正面，故可獲得高的正面亮度。又，從光控制片射 出的光，係爲隨著從正面向斜方向成爲廣角度而亮度單調 地降低之分布，由於光控制片的凸部之形狀係爲平滑的曲 面而不易受傷。因此，不必爲了修正出射光的亮度分布、 防止受傷而將擴散片配置於光控制片的出射面側，而使高 的生產效率及低成本化爲可能。 藉此，本發明之光控制片的凸部配置成平行於X軸， 而可使Y軸方向的光聚焦而偏向至正面，同時具有將平行 於X軸方向的光加以廣角化的功能。 一般，在使用監視器等之畫面顯示裝置的情況，在水 平方向希望有寬的視角。因此，在以光控制片將視角變窄 ，聚光於正面方向之情況，與其進行水平方向的聚光，不 如聚光於上下方向爲較佳。由於本發明之光控制片的凸部 係配置成平行於X軸，以使X軸方向成爲水平方向的方式 設置本發明之面光源元件，藉此可有效地實現此種希望的 -24- 200817793 聚光。 滿足此種條件之光控制片的凸部，平行於X軸方向且 平行於以Y軸及Z軸構成的Y-Z平面之凸部的截面之輪廓 線對Y軸的傾角0，必須具有具備朝以凸部之頂點爲中心 的兩方向單調地增加之範圍的平滑的曲面。藉此，被折射 而射出的光之角度亦在正面附近分散，而獲得從正面方向 朝斜方向單調地亮度降低之平滑的出射光之角度亮度分布 。又，由於在頂部具有曲面，頂部不易產生缺口，不須要 爲了防止受傷而放置擴散片，可獲得高的生產性。 又，在輪廓線之對Y軸的傾角0滿足上述公式（I)及公 式（II)之情況，可有效地使從導光板射出的光朝向正面。 當0 ’比此範圍小之時，則凸部的光偏向正面的比率 變小，又當0 ’爲大之時，從正面傾斜地射出之光變多， 使光之利用效率降低。 又，光控制片的凸部平行於X軸方向，且平行於以Y 軸及Z軸構成的Y-Z平面之凸部的截面形狀，係以橢圓之 長軸的一端爲頂點的橢圓之一部分所形成的局部橢圓形狀 ，且局部橢圓形狀之切線對Y軸之傾角的絕對値爲60°至 8 0 °的範圍內之時，使傾斜地射入之光偏向正面，可獲得在 廣角度側亮度降低的平滑的亮度之角度分布。 又，高度h對部分橢圓形狀之與Y軸平行之寬度p的 比之所謂高寬比’係由局部橋圓形狀之切線之傾角的最大 値與凸部之頂部的高寬比來決定，此比値在0 · 3 9至0 · 5 3的 範圍內之時，朝正面方向射入的光亦可有效率地朝正面附 -25- 200817793 近射出，因此可獲得更高的光利用效率。 又，光控制片的凸部平行於X軸方向且平行於以Y軸 及Z軸構成的Y - z平面之凸部的截面形狀，係爲由包含拋 物線之頂點的拋物線之一部分形成的局部拋物線形狀，局 部拋物線形狀之切線對Y軸之傾角的最大値爲自52°至62° 的範圍內之時，可使於傾斜方向入射之光更多地偏向正面 方向。對局部拋物線形狀之與Y軸平行之寬度p的比，係 由局部拋物線形狀之切線之傾角的最大値來決定，當傾角 的最大値爲自52°至62°的範圍內之時，此比値在0.32至 0.4 7的範圍內。 又，本發明之光控制片可效率良好地提高本發明之面 光源元件的正面亮度。又，與稜鏡片比較，凸部不易受傷 ，且可獲得平滑的出光分布。 在此’在公式（I)中，設置於光控制片的出射面之壟狀 之凸部，較佳爲0.450 maxS (9 ’$0.700 max。此時可更有 效地將光朝正面方向偏向，故可獲得高的正面亮度。 又’較佳爲 0.450 maxS 0’SO.680 ，更佳爲 0.460 maxS Θ ’ S 0.65 0 max。此時，可使光更有效地朝正面偏向 ’而獲得高的正面亮度及高的亮度均勻性。 本發明中，此光控制片之凸部的Y-Z平面之截面形狀 係’例如’以橢圓之短軸的一端爲頂點的橢圓之一部分所 形成的局部橢圓形狀，或者由包含拋物線之頂點的拋物線 之一部分形成的局部拋物線形狀爲較佳。 當光控制片之凸部爲局部橢圓形狀之情況，0 max爲 -26- 200817793 自6 3 °至8 0 °，高寬比爲〇 · 4 2至〇 . 5 2爲較佳。此時，使光效 率良好地偏向正面，而能獲得高的亮度均勻性。又’爲了 製作凸部而將凸部反轉後的溝狀凹部作爲母模而使用的情 況’爲了提高母模的強度而獲得高的生產效率，0 max爲 自69°至75°，高寬比爲0.43至0.48爲較佳。 當光控制片之凸部爲局部拋物線形狀之情況，0 max 爲自53°至58°，且高寬比爲0.34至0.43爲較佳。此時，可 使朝斜方向射入的光朝正面方向聚光，而獲得高的亮度均 勻性。又，0max爲自55°至57。，高寬比爲〇·36至0.39時 ，更可獲得高的正面亮度爲較佳。 光控制片之凸部係凸部的寬度p以1 // m〜500 # m爲較 佳。當大於5 Ο Ο /Z m時，從出射面可視認此圖案，故外觀品 質降低。當小於1 // m時，由於繞射現象而著色，故而招致 外觀品質降低。更佳爲20// m〜300// m，最佳爲在30//m〜200 # m。在此範圍中不易觀察圖案之視認，又凸部之製作變成 容易且生產性提筒。 本發明中雖然並未限定光控制片的厚度，但考慮光控 制片本身的強度、生產性等仍以設定光控制片的厚度爲宜 。雖厚度係視面光源元件的大小而不同，但以0.05 // m〜1mm 爲宜。當比此更薄時，由於光控制片本身的強度降低、變 形等更使品質降低。又，當比此更厚時，面光源元件變厚 ’且重量亦增加。又，爲了防止由於光控制片之熱等引起 的變形，且爲了以擠出成型等獲得生產性，在0· 1mm〜0.7mm 的範圍內較佳，又，在0.2mm〜0.5mm的範圍內更佳。 -27- 200817793 光控制片的製造方法可舉出擠出成型、射出成型、2P 成型等，但只要考慮凸部之大小、凸部之形狀、量產性等 而選擇適當的成型方法即可。主面的短邊、長邊均超過 4 0 0 m m等，大型的面光源元件用之情況，以擠出成型爲適 宜。又，厚度小於1 mm之薄的情況，以擠出成型、2P成型 爲適宜。 其次，將參照圖面說明本發明之面光源元件的變形例 〇 首先，第4圖是使用將在導光板1之對向兩側面的各 2條線狀光源4 a作爲一次光源4而配置的本發明之面光源 元件1 0之例來顯示大型的液晶畫像顯示裝置之構成。在此 ，第4(a)、（b)圖分別爲從平行於X-Z平面之側向Y軸方向 觀察時之側面圖、及從平行於Y-Z平面之側向X軸方向觀 察時之側面圖。 在出射面6及底面7之兩側面配置有一次光源4，其 係在反射器4b內分別配置一對線狀光源4a。爲了充分確保 從線狀光源4 a射入到導光板1內的光量，而使用厚度厚的 導光板1。藉此，配置此等一次光源4的兩側面係作爲入 射端面8，與此入射端面8交叉的兩側面係作爲反射端面 8b ° 又，第4圖之面光源元件，在出射面6的上方配置有 擴散片5 a及本發明之光控制片1 1。擴散片5 a配置於導光 板1與光控制片1 1之間，能藉以使面光源元件10的出射 光適度地均勻化而提高品質。又，藉著選擇適當的擴散片 -28- 200817793 5a亦可更進一步提高正面亮度。 在第4圖之面光源元件1 〇中，截面爲梯形狀的凸條2 及與此凸條2之梯形爲上下反轉的梯形狀之凹條3係交互 地排列在出射面6上。此等之凸條2及凹條3係與上述第1 圖、第2圖所示之凸條2的梯形之表面1 a實質上相同，因 此其詳細說明省略。依此方式，與入射端面8正交的截面 爲梯形形狀的凸條及凹條係多數個配置在此出射面6。 另一方面，截面爲梯形狀的凸條9互相接觸而平行地 排列在底面7。藉著逐步地調整此梯形狀的凸條9的大小 ，可調整從出射面6射出的光之光量分布。 線狀光源4 a的光從導光板1的入射端面8入射到導光 板1內，在出射面6與底面7之間反覆進行全反射同時於 縱方向傳播。 其後，此光之一部分藉由形成於底面7的梯形狀之凸 條9及反射片5而導向出射面6，形成於出射面6的截面藉 由梯形形狀的稜鏡（凸條2及凹條3)而聚光，以射出到所要 的視角內。 依此方式，藉由在出射面6形成截面爲梯形形狀的稜 鏡，與在出射面6形成V溝之稜鏡的情況比較，可抑制筆 直方向之亮度降低，且可擴大視角。 作爲此種導光板或光控制片的材料，只要係通常的光 學透明材料的話便可使用。例如可舉出甲基丙烯酸樹脂、 聚碳酸酯樹脂、環烯烴樹脂、聚苯乙烯樹脂、甲基丙烯酸-本乙細共聚合樹脂、运儲煙-鍵細共聚合物樹脂。此等透明 -29- 200817793 樹脂大致具有大於1.4之折射率。作爲滿足本發明之條件 的折射率，以1.42至1.65的範圍內爲較佳。 又，爲了更提高亮度的均勻性，亦可在本發明之面光 源元件所具備的導光板及/或光控制片設置光擴散手段。作 爲光擴散手段可舉出如：在導光板或光控制片的主面設置 凹凸紋或凸起等之隨機的凹凸的方法、將使少量的光擴散 的微粒子設置於構造物之內部的方法、將擴散片設置於導 光板或光控制片的入射面側及/或出射面側的方法、或將此 等加以組合的方法。隨機之凹凸可藉由將微粒子已分散的 溶液以噴灑等對主面塗布、將微粒子已分散的樹脂擠出而 成型、由凹凸之已成型的模具進行轉印而實現。凹凸的程 度以算術平均粗度R a爲3 // m以下爲較佳。大於此値時， 擴散效果變得太大，因此正面亮度降低。 例如，梯形形狀之圖案，如第12(a)圖所示，雖然係以 天頂面（上底）2a及傾斜面2b均爲鏡面之例，但是亦可將此 等之表面加以粗面化。 例如，如第12(c)圖所示，將梯形稜鏡（凸條2)之傾斜 面2b加以粗面化時，與第12(a)圖所示全面爲鏡面之情況 比較，視角更擴大，且可達成作爲面光源元件1 〇緩和表面 的眩光感，或從斜方向視認導光板之角落部時產生的暗線 狀之線條等的表面品質之提高。 又’如第12(d)圖所示，將梯形棱鏡（凸條2)之天頂面 2a及傾斜面2b之全面加以粗面化時，與第12(c)圖所示僅 將傾斜面2b加以粗面化之情況比較，雖然表面亮度多少會 -30- 200817793 降低’但是可達成作爲面光源元件緩和表面的眩光感，或 暗線狀之線條等的表面品質之更進一步提高，適於將視角 及表面品質視爲重要的面光源元件。又，依此方式獲得的 液晶顯示裝置，表面品質變成優異。 如此的粗面化，例如根據ns B 060 1之算術平均粗度 (Ra)爲0.1// m〜10// m的範圍內爲較佳。更佳爲在0.15// m〜5 // m的範圍內，特佳爲在〇.2 # m〜2 // m的範圍內。又，如 此的粗面化，如第1 2 (b)圖所示，雖然可僅在凸條2之上底 (天頂面）2a實施，但是如第12(d)圖所示，亦可在天頂面2a 及傾斜面2b之雙方實施（全面擴散面）。又，如第12(c)圖所 示，亦可僅在側面部（傾斜面2b)實施。再者，此粗面化亦 可在凹條3之上底（天頂面）3a實施。藉由將表面加以粗面 化而形成擴散面，藉此使出射的光無論在任何情況均可期 待表面品質之提高。 又，本發明之畫像顯示裝置係藉由在面光源元件上設 置透過型之顯示裝置而實現，作爲顯示裝置可舉出透過型 之液晶面板等。藉此，可獲得顯示面的亮度高，且亮度均 勻性優異的畫像顯示裝置。 在此情況下，在本發明之面光源元件的出射面側設置 透過型顯示裝置的畫像顯示裝置，較佳爲透過型顯示裝置 之畫素間距的1/100至1/1.5。大於此値時，會產生畫素間 距的干涉條紋而使外觀品質降低。 實施例 以下，藉實施例具體地說明本發明之效果。 -31- 200817793 (實施例1) 將東京應化工業股份有限公司製作的負型光IS齊!1 (C A 3 0 00)塗布於清潔的玻璃上’在110°C的熱板上溫熱2分 鐘之後冷卻到室溫。將此玻璃基板與以既定間隔設置狹縫 的光罩加以緊貼’以用1 2 0秒進行從-3 5 °至+ 3 5 °的旋轉的速 度進行動作，在此期間照射1 400ml之UV光。將光罩剝離 後，將此基板顯像。將所製成的原盤依照常法在表面形成 錬導電化膜’在此錄導電化膜上將錬作爲電繪用金屬而進 行電禱以形成錬電繪層。又’從錬導電化膜將原盤加以剝 離，而製作出成型爲高度〇.〇imm、在頂上部分具有寬度約 1 0 // m的平坦部、傾斜角爲5 5 °之梯形形狀圖案的出射面側 的壓模（stamper)I。 另一方面，以鑽石切刀在直接模具套件上進行切削加 工而製作頂角100°、高度0.01mm之V字狀的溝條，由此 切削套件進行直接電鑄，而形成鎳電鑄層。將原盤剝離， 而製作出成型爲高度0.01mm、頂角爲100°之稜鏡圖案以既 定間隔排列而成的底面側之壓模II。 將此等之壓模I及壓模II作爲轉印模具而組裝到射出 成型機之模具固定側腔室及模具可動側腔室中，利用射出 成型法而得到具有1 7英吋顯示器用之微細構造的導光板1 ( 板厚6mm)。 製成的導光板1具備截面形狀爲梯形形狀的凸條隔開 間隔而配置的出射面，及截面形狀爲梯形形狀的凸條連結 而配置的底面。此出射面之梯形凸狀形狀，高度Η爲1 0 // -32- 200817793 m、天頂部寬度W2爲l〇//m、底面寬度W1爲24//m，底 面之梯形凸狀形狀高度爲10// m、底角al及a2爲40° ’又 下底爲從冷陰極管側到中央部爲逐漸從1 80 // m調整變更 爲 6 0 // m 〇 又，本發明之光控制片，係藉由切削加工在滾筒狀模 具上使光控制片的壟狀凸部（間距p80// m)加以反轉之形狀 的溝狀凹部平行地連續而製作，使用所製成的滾筒狀模具 ，藉由已使苯乙烯-丁二烯橡膠狀共聚合物約10重量％分散 的甲基丙烯酸甲酯-苯乙烯共聚合物樹脂（折射率1.54)擠出 成型而製作。 在此，本實施例之光控制片11係厚度〇.4mm，其凸部 之 Y-Z平面的截面形狀係依照下式，此等之係數是爲 C = 3.24xl0·2、K = -0.44、hmax = 41.7 〇 %m) = /2inax~ C¥2BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an edge-light type surface light source element, a light control member used therewith, and an image display device using the same. The surface light source element used in the image display device has two methods of edge light type and direct type. However, the edge light type surface light source element is a linear light source located on the side surface of the light guide plate. In comparison with the surface light source element of the direct type, it is characterized in that it is effectively thinned. Therefore, a display unit such as a portable notebook type personal computer or a monitor is widely used. In the edge light type surface light source element, a light guide plate made of a transparent resin or the like and having a main surface having a generally rectangular shape is used. The light guide plate has an incident end face of a primary light source such as a linear light source or a point light source between an exit surface belonging to one of the main surfaces and a bottom surface belonging to the other main surface facing the exit surface. The light emitted from the primary light source is incident on the inside of the light guide plate through the incident end surface of the light guide plate, and is guided inside the light guide plate, and is scattered by the scattered point (white point) formed on the bottom surface of the light guide plate, or The film is once ejected from the bottom surface of the light guide plate, and is scattered by the reflection sheet facing the bottom surface and disposed on the reflection surface, and is incident on the light guide plate or the like, and is emitted from the emission surface toward the liquid crystal display element portion. The light guide plate of the printed dot method 200817793 which prints the scattered dots (white dots) on the bottom surface of the light guide plate is adjusted by adjusting the size, density, and the like of the dots so that the brightness distribution in the viewing direction becomes uniform. Adjustment. Thereby, the light emitted from the primary light source enters the light guide plate from the incident end surface, and the incident light is transmitted inside the light guide plate while emitting light from the emission surface toward the liquid crystal display element portion. The surface light source of the light guide plate using the printing dot method is used. Since the light is scattered by the components at the scattered points, the light emitted from the light guide plate is diffused into a wide-angle light distribution, and the alignment and brightness which are important in the front direction on the surface light source element cannot be sufficiently obtained. Therefore, in order to condense the light emitted from the light guide plate in the front direction to increase the luminance, a plurality of diffusion sheets are used, and a slab (directivity sheet) is used in addition to the diffusion sheet. The diffusion sheet is formed by applying a liquid in which the diffusing fine particles have been dispersed to one side or both sides of the sheet, and the resin in which the fine particles are dispersed is formed into a sheet shape, and the inner or surface sheet in which the diffusing fine particles are dispersed is incident on the sheet. The light of the sheet is diffused by the diffusing particles that have been randomly dispersed. For example, when the surface of the surface-coated type diffusion sheet is observed, a region where the diffusing fine particles are microscopically coated and a flat surface not coated with the diffusing fine particles are mixed. Such a diffusion sheet was found to have a small scattering effect on light incident from the front direction of the diffusion sheet, and a large scattering effect on light incident on the front direction at a large incident angle. The light emitted from the exit surface of the light guide plate of the printing dot method is distributed substantially in all directions. When one of the above-mentioned diffusion sheets is placed on the light guide plate, the light emitted in the vicinity of the front direction is transmitted as it is as it is 40 with respect to the front direction. A part of the above-mentioned light is deflected in the front direction due to the 200817793 diffuser, so the front direction is bright. However, the particles of the diffuser distribute the light toward the random direction to distribute the incident light functionally to the destination. Therefore, it is not easy to effectively improve the direction of the desired front direction. Even if the sheet is re-dispersed in order to expect a more forward direction, the light distribution of the light emitted from the diffusion sheet is not advantageous for the improvement of the viewing angle characteristics. On the other hand, the enamel film can more effectively improve the light emitted from the front cymbal. Generally, as shown in Fig. 14, the squad is lowered, and the area with high brightness is generated above 50°, which is a better image quality. Problems such as reduced energy efficiency. Therefore, in the case where the cymbal is disposed, in order to change the cloth to be monotonously brightly distributed in a wide angle toward the oblique direction, and to prevent the cymbal from being injured, it is necessary to make the exit surface side of the diffusion sheet. Therefore, in the case of arranging the ruthenium, there is a problem that the luminance is lowered, the production efficiency is lowered, and the number of parts of the optical sheets is increased. Therefore, although these sheets are easily wrinkled by using 100 to 300 // m, they become wrinkles of the lens which occurs in the defective product of the combined process, and the illumination quality of the surface light source element is remarkably improved. The problem of the deterioration of the appearance of the prism is a cause of a decrease in the appearance quality. However, the problem is to develop a cymbal that changes the top to a curved surface, but the degree can be increased by a certain amount of diffusion, so the ability is low. That is, the light ratio. The use of multiple sheets in the stack is expanded to be isotropic and reduced. brightness. However, the brightness near E 30° therefore has a natural sheet that cannot be reduced by some unnatural indexing, and the prism is required to diffuse the sheet, which is improved. It is thinner than thinner, but the cause is especially low. A sharp top is easy to solve. This will reduce the ability to increase the front brightness of 200817793. On the other hand, in recent years, in order to increase the number of avoidance points in the high-brightness process, it is proposed to form a cymbal on the bottom surface of the surface of the light-emitting surface of the light guide plate, and to emit the light from the exit surface (for example, refer to the patent). Documents 1 to 4). For example, Patent Document 1 proposes a light guide plate in which a right angle or a slanted ridge (or a groove 5 of a concave groove) is formed on an incident end surface, and a printed dot or a concave light guide plate is disposed on a bottom surface opposite to the exit surface. When the light introduced into the light guide plate is guided deep, it is possible to omit the cymbal for the lower side mounting which is provided so as to form the groove with respect to the incident end surface (the directionality is less as described in Patent Document 1 It is proposed that the above-mentioned ridges can be omitted (or [two slabs can be omitted. Further, in Patent Documents 2 and 3, a 稜鏡 optical optical illuminator is disclosed. In this 稜鏡 optical element integrated type light guide plate The middle and the bottom surfaces each have a V-shaped groove row in the intersecting direction, and the light incident from the end face is taken in the bottom surface, so that the reflected light has the direction of the exit surface, and when the film is formed on the exit surface, The incident exit surface incident in a direction perpendicular to the incident end surface is emitted at an angle close thereto. Further, Patent Document 4 discloses a ridge and a concave pattern and a bottom surface in which the light guide plates are alternately arranged at a predetermined interval. Mutual In the case of such a light guide plate, the use of the directional sheet such as a cymbal sheet is extremely omitted, and such a component and the opposite light illuminating direction are disposed so as to be opposite to each other. To the light guide plate in the direction of the right angle f). In addition, according to the three grooves, the component is integrated. On the exit surface, the light will be reflected from the effective surface and the light energy from the exit surface will be vertical. The exit surface provides a light guide that ensures viewing angle without reducing the brightness of the pen in the straight direction of 200817793. Patent Document 1: Japanese Patent Application Laid-Open No. Hei 9-61631 (Patent No. 6, No. 8 and No. 003 8) Patent Document 2: Japanese Patent Application Laid-Open No. Hei 10-282342 Japanese Unexamined Patent Application Publication No. Publication No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No It is formed by crossing, and the use of two directional sheets can be omitted, but there is a problem that a certain amount of diverging light cannot be avoided. Further, in the 稜鏡-optical element-integrated light guide plate described in Patent Document 2 or 3, the ridges or the grooves formed on the exit surface and the bottom surface are grooves of the V-shaped strip whose apex angle is an acute angle. In the edge light source element type light-emitting device using the 稜鏡-optical element-integrated light guide plate having the groove of such a V-shaped strip, the light source is less likely to be emitted in the straight direction (normal direction), and the angle of view is narrower. . Further, depending on the situation, the brightness of the brightness is conspicuous due to the viewing angle. Therefore, not only the surface glare is noticeable, but also when the corner portion of the rectangular light guide plate is viewed obliquely, a dark line is observed. The problem of reducing the picture quality. Therefore, in such a 稜鏡-optical element-integrated light guide plate, it is necessary to use one to two diffusion sheets, and the angle of view is widened while ensuring the brightness in the straight direction. Therefore, there is a problem that the overall brightness is reduced. Further, according to the light guide plate described in Patent Document 4, the trapezoidal ridges and the trapezoidal shape 200817793-shaped recesses are alternately arranged on at least one of the exit surface and the bottom surface, and the brightness in the straight direction can be increased. The degree ensures the angle of view, but it is still expected to be further improved. Accordingly, an object of the present invention is to provide a surface light source element and an image display device which can improve the brightness in the front direction and increase the viewing angle. Further, another object of the present invention is to provide a light control member for use in such a surface light source element. [Means for Solving the Problem] In the present invention, the light guide plate having the pattern of the ridges that are orthogonal to each other on the exit surface and the bottom surface facing the exit surface, and the light having the specific ridge-like convex portion on the exit surface The combination of the control pieces solves the above problems. That is, the surface light source element of the present invention is an edge light type surface light source element in which at least one linear light source is disposed on at least one side surface of the light guide plate, wherein the light guide plate has an exit surface and is opposite thereto. a bottom surface of the emission surface and an incident end surface into which the light emitted from the linear light source is incident, a reflection means for reflecting light on the bottom surface side of the light guide plate, and a control unit from the light guide plate on the emission surface side of the light guide plate The light control member in the direction of the emitted light has a normal axis of the X-γ plane formed by the X-axis and the γ-axis orthogonal to the X-axis, and the linear light source is arranged parallel to the X-axis. The reflection means, the light guide plate, and the light control member are disposed in parallel with the XY plane in the Z-axis direction in the order of the reflection means, the light guide plate, and the light control member, and the incident end surface of the light guide plate is Parallel to the X-axis, a pattern of ridges is formed on the exit surface and the bottom surface, and the pattern formed on the exit surface is parallel to the Y-axis, and the pattern formed on the bottom surface is parallel to the X-axis. The light control member forms a plurality of ridge-shaped convex portions parallel to the X-axis on the side where the light main -10-200817793 is emitted, and a contour of a cross section of the convex portion parallel to the YZ plane formed by the Y-axis and the Z-axis. The line has a curved portion including at least a top portion, and the inclination angle 0 at which the tangent line of the contour line and the Y-axis intersect are monotonously increased in the two directions centering on the apex of the convex portion, respectively satisfying the following formula: 450 maxS 0 0. 75 (9 max 0. 25p^ I Ymaxl where 0 max : the maximum 値Ymax of monotonically increasing from the vertex of the contour line: the position of the Y-axis direction when the monotonically increasing 0 from the vertex of the contour is taken as 0 max Y?= Ymax/2 0 ' : the inclination angle of the tangent of the contour line at the position of Y ' in the Y-axis direction with respect to the Υ axis: the width of the contour line in the direction parallel to the Υ axis, and the above-mentioned surface light source element of the present invention is applied for The surface light source element of the first aspect of the patent is characterized in that the cross-sectional shape of the Υ-Ζ plane of the convex portion of the light control member is a partial ellipse formed by a part of an ellipse having one end of the major axis of the ellipse as a vertex. a shape in which the maximum entanglement of the tangent of the partial elliptical shape with respect to the Υ axis is in a range from 60 degrees to 80 degrees, and the ratio of the height h to the width P of the partial elliptical shape parallel to the γ axis The § stomach aspect ratio is from 0. 39 to 0. Within the scope of 53. Further, the above-mentioned surface light source element of the present invention is a surface light source element according to the first aspect of the invention, wherein the cross-sectional shape of the convex portion of the light control member in the YZ plane is comprised of a parabola. a partial parabola shape formed by a portion of the parabola of the apex, the maximum entanglement of the tangent of the local parabolic shape to the Y-axis from the range of 52 degrees to 62 degrees, and the height h versus the local parabolic shape and the γ-axis The ratio of the width P of the parallel directions is the ratio of the so-called aspect ratio from 0. 32 to 0. Within the scope of 47. Further, the present invention is directed to the surface light source device described above, characterized in that the cross section of the X-axis plane formed by the X-axis and the Z-axis of the pattern on the exit surface side of the light guide plate is formed to be parallel to the X-axis. a bottom portion and a trapezoidal shaped rib connected to the two oblique portions of the upper bottom portion, the height of the trapezoidal shape being in the range of 1 // m to 1 0 0 // m, and the oblique portion being on the X-axis The inclination angle is in the range of 15° to 70°, and the width of the upper bottom is in the range of 1/zin to 500 // rn. 'The cross section of the γ_Ζ plane of the above pattern on the bottom surface of the light guide plate is formed with a Y-axis parallel to the upper bottom and a trapezoidal shaped rib connected to the two oblique sides of the upper bottom. The height of the trapezoidal shape is in the range of m~1 0 0 // m, and the oblique portion The tilt angle to the γ axis is at 3 2. 5. In the range of ~45°, the width of the upper bottom is in the range of 3/z m to 1600# m. 本 The present invention is a light control member used in the above-described surface light source element. Further, the present invention provides an image display device comprising a transmissive display element on an exit surface side of a light control member of the surface light source element. [Effects of the Invention] According to the present invention, a surface light source element and an image can be provided. Display -12- 0 200817793, while increasing the brightness in the front direction, while increasing the viewing angle. [Embodiment] Hereinafter, the best mode for carrying out the invention will be described. Further, in the following drawings, for the sake of convenience of explanation, a schematic diagram of arbitrarily changing the vertical and horizontal dimensions of the respective portions will be described. First, as shown in Fig. 1 and Fig. 2, the surface light source element 10 of the present invention is an edge light type surface light source element which is mainly composed of a light guide plate 1 and a flat plate formed of a transparent resin or the like (panel shape). a transparent structure; the primary light source 4 is disposed on one side of the light guide plate 1; the reflective sheet 5 is disposed under the light guide plate 1; and the light control sheet 1 1 is made of a transparent resin disposed on the upper surface of the light guide plate 1 It is formed as a light control member. In such a surface light source element 10, the X-axis and the normal line of the X_Y plane orthogonal to the Y-axis of the X-axis are taken as the Z-axis, and the light guide plate 1 has an incident end face 8 parallel to the X-axis, parallel to the Χ-Υ. The exit surface 6 and the bottom surface 7 of the plane, the primary light source 4 is disposed in parallel with the incident end surface 8 of the light guide plate 1, and the light incident from the incident end surface 8 is emitted from the exit surface 6 of the light guide plate 1, and the light transmission sheet 1 is transmitted. 1 Shoot in the direction of the Ζ axis. The light control member can also be supported on the light guide plate. Thereby, a mechanism for fixing the light control member is not required, and since stress concentration on the fixed portion is caused on the light control member due to heat of the device or the like without being fixed, the damage or the light control member can be suppressed. Significant deformation. Further, even when the light control member is made thin, it can be supported by the light guide plate, so that the deflection is less likely to occur. [Description of Light Guide Plate 1] -13- 200817793 The light guide plate used in the present invention is used for the edge light type surface light source element, and the pattern of the ridges of the exit surface and the ridges facing the bottom surface of the exit surface While maintaining a wide viewing angle, one side has the function of obtaining high brightness. The light guide plate 1 used in the present invention can be composed of a transparent resin having a high light transmittance. As such a transparent resin, for example, a methacrylic resin, an acrylic resin, a polycarbonate resin, a polyester resin, a cyclic polyolefin resin or the like can be widely used. In the present invention, one surface of the light guide plate 1 serves as an exit surface 6, and the bottom surface 7 is disposed to face the exit surface 6. Further, the primary light source 4 is disposed on at least one side of the light guide plate 1, and the side surface serves as the incident end surface 8. In the present invention, the incident end face 8 may be at least one place as shown in the drawing, but may be plural, and the incident end face 8 may be one place, and the reflective end face 8a may be formed on the side other than the incident end face 8. . A typical example of the case where the incident end faces 8 are two, as shown in the later-described embodiment, is an example in which a linear light source as a primary light source is formed on the surface facing each other. The reflection end faces are formed on both side faces. The incident end faces 8 of the two places must satisfy: either one of which is orthogonal to the pattern formed on the exit face 6, and which is parallel to the pattern formed on the bottom face 7. The primary light source is disposed to face the incident end face 8. When the primary light source is a linear light source, any type may be used. However, a linear light source or a point light source such as an LED light source may be used to form a linear light source (linear light source). In the present invention, the patterns of the ridges 2 and 9 formed at a predetermined interval of -14 to 200817793 on both sides of the exit surface 6 and the bottom surface 7 of the light guide plate are formed to be orthogonal to each other. These ribs 2, 9 include the ribs 2, 9 of the trapezoidal shape which will be described below, and may be substantially the same or equal to the ridges 2, 9 used in the conventional surface light source elements. These ribs 2, 9 are formed so that the convex portions protruding in a cross section extend in one direction. The cross-sectional shape of the ridges may be a desired shape such as a triangle, a wedge, another polygon, a wave, or a semi-ellipse. Here, although the ridges 2 formed on the exit surface 6 can be arranged in the same pitch and shape, the ridges 9 formed on the bottom surface 7 can be arranged in a shorter pitch away from the primary light source, and can be separated from the light source. The height of the ridges is gradually increased. Further, the shape may be gradually different as it is away from the primary light source. Such a configuration in which the shapes are gradually different includes, for example, in the case where the cross-section has a trapezoidal shape, the lengths of the trapezoidal upper bottom and/or the lower bottom are gradually different. In either case, the light refracted by the bottom surface 7 and the reflection sheet 5 is emitted from the exit surface 6 at a desired intensity for controlling the structure of the bottom surface 7, and the adjustments can be combined with each other or with others. Adjustment measures are used. When the light guide plate 1 provided in the surface light source element 10 of the present invention has the projections 2 and 9 having a trapezoidal shape in the cross section of the light-emitting surface 6 and the bottom surface 7, the front surface brightness in the visible direction becomes higher. And the viewing angle characteristics become a wider point, which is a better form. Here, the trapezoidal ribs 2 and 9 are ridges which are formed in a trapezoidal shape from the light guide plate toward the front side and extend in the longitudinal direction. For example, on the surface of the light guide plate 1 shown in FIG. 3, on one surface -15-200817793 1 a, the symbols A, B, C, and D are used as the ridges of the apexes with the trapezoidal ribs 2, 9 and The symbols A ', B ', C', and D' are arranged as the ridges 2', 9' in which the cross-section of each vertex is trapezoidal. The trapezoid of the present invention is not limited to a trapezoidal shape as shown in the figure. As will be understood from the description which will be described later, as long as the upper and lower bottoms of the plane which are different in height from the XY plane are connected and held in a mountain-shaped inclined plane, for example, even if the upper or lower bottom is connected to the inclined surface, It is also possible to have a curved surface. The trapezoidal shape having such a curved connecting portion is preferable because it is easy to form, which is advantageous not only in production but also in that the joint portion is not easily broken. Further, at least a part of the upper bottom and the lower bottom may have an inclination with respect to the XY plane, for example, the upper bottom and the lower bottom may have a gentle wave shape in which the X-axis direction is the longitudinal direction, or may have fine irregularities. And improve the uniformity of the light. The average of the inclination angles is preferably not angled with respect to the X-Y plane. Further, it is preferable that the portion having an inclination angle of 10 or less is 50% or more of the total. Further, the plurality of upper bases 2a, 2a', 9a, and 9a' are lowered to the bottom, and each of them is in the same χ-γ plane, and not only the light can be efficiently extracted, but also the center of gravity of the light guide plate can be stabilized. Industrially, advantageous continuous production can be facilitated by extrusion molding, and a useful effect in practical use can be achieved. Next, for the function of such a trapezoid, the exit surface 6 will be described as an example using Fig. 3. Although the terms "upper bottom" and "lower bottom" are used, they do not mean that they are in the up and down direction for the sake of explanation. Among the parallel sides of the trapezoid, the short side is referred to as "upper bottom" and the long side is referred to as "lower bottom". First, in this third figure, the length of the straight line AD (the width of the bottom of the rib 2 is -16-200817793) is W1, and the length of the straight line BC (the width of the upper base 2a of the ridge 2) is W2. Let the length of the straight line AD' (the width of the upper bottom 3a of the concave strip 3) be W3, and the height of the convex strip 2 (or the depth of the concave strip 3) be Η, and the straight line AD and the straight line ΑΒ (inclined surface 2b) The angle is a1, the angle formed by the straight line AD and the straight line DC (inclined surface 2c) is taken as a2, and the length of the straight line DD' is taken as the pitch P. The pitch P is equal to the sum of the width of the lower base of the rib 2 (the length of the straight line AD) W1 and the width W 3 of the upper base 3 a of the concave strip 3, and is equal to the width of the upper base 2a of the ridge 2 (straight line BC) The length) is the sum of the width of W2 and the bottom of the concave strip 3 (the length of the straight line BC'). In the exit surface 6 of the light guide plate 1 provided in the surface light source element of the present invention, the cross-sectional shape of the ridge 2 is formed into a trapezoidal shape, and the ridge 2 is provided with a suitable width W2, thereby causing the incident end face 8 to be shot. The entrance light guides the role of the center of the light guide plate, and the brightness in the straight direction (normal direction) orthogonal to the exit surface 6 in the luminance distribution emitted from the exit surface 6 can be increased. Further, in the exit surface 6 of the light guide plate 1 included in the surface light source element of the present invention, the cross-sectional shape of the concave strip 3 is formed in a trapezoidal shape, and the concave strip 3 is formed to have a desired width W3, thereby achieving the above-mentioned W2. Similarly, the role of the light incident from the incident end face 8 to the inside of the light guide plate in the Y-axis direction is performed, and the straight direction orthogonal to the exit surface 6 in the luminance distribution emitted from the exit surface 6 can be improved (normal) The brightness of the direction). When the width W2 is too narrow and the contribution of the inclined faces 2b and 2c becomes too large, it is difficult to sufficiently exhibit the effect of improving the brightness in the straight direction. Further, when the width W3 is too narrow and the contribution of the inclined faces 2b and 2c becomes too large, it is difficult to sufficiently exhibit the effect of improving the brightness in the straight direction. In contrast, when the width W2 and/or the width W3 are set to be relatively too wide with respect to the inclined faces 2b and 2c, the contributions of the inclined faces 2b and 2c are relatively small. Then, although the brightness in the straight direction can be improved, the viewing angle becomes narrow, and the problem that the directivity sheet is extremely omitted and the viewing angle is sufficiently ensured without lowering the brightness in the straight direction cannot be sufficiently satisfied. In the exit surface 6 of the light guide plate 1 provided in the surface light source element of the present invention, the shape, size, and pitch P of the rib 2 or the recess 3 are considered to be the same as the size of the light guide plate 1 and the surface light source element 1 〇 The relationship between performance and specifications is determined. Thereby, the brightness of the light emitted from the exit surface 6 of the light guide plate 1 can be appropriately maintained, and an appropriate viewing angle can be obtained. The general height H of such a rib 2 (or the recess 3) is selected from the range of 1 // m to 100 // m, and the preferred height is 5 // m to 50 // m, most The best degree is selected from the range of 10//m~30//m. Further, a general inclination angle a1 and an inclination angle a2 are selected from the range of 15° to 70°, and a preferred inclination angle a1 and an inclination angle a2 are selected from the range of 15° to 60°, respectively. Especially in the case of paying attention to the characteristics of the viewing angle, it is preferable to select it in the range of 1 5 ° to 3 5 °; in the case of paying attention to the brightness characteristic, it is preferable to select it in the range of 3 5 ° to 60 °. Further, generally, the width W1 of the lower bottom is selected in the range of 10//m to 500//m, more preferably in the range of 15//m to 270/zm, and most preferably 15//m~ Choose within the range of 180//m. Further, the width W2 of the upper base is selected in the range of 1/zm to 500//m. The more preferable width W2 is selected in the range of l//m to 100//m, and most preferably 5/zm. Choose from a range of ~5〇//m. Also, the general width W3 is at 0. 1 / zm ~ 500 / zm range -18 - 200817793 choice, better width W3 is at 0. The range of 1//m to 300/zm is selected, and it is preferably selected within the range of l//m to 150//m. In the present invention, the exit surface 6 of the light guide plate 1 is preferably a trapezoidal pattern formed by maintaining a specific ratio due to the relationship between the widths W1, W2, W3 and the pitch P. That is, in the present invention, it is preferable that the ratio of the width W3 formed on the upper surface of the concave strip 3 to the width W3 formed on the upper surface of the ribs 2 (W3/W2) is the exit surface 6 of the light guide plate 1. To 0. The range of 01 to 200 is preferably, more preferably 0. Within the range of 02~100, the best is in 〇. Within the range of 1 to 1 。. Also, the ratio of (?-\¥2-,3) to (^¥2 + \\^3) is in 〇. It is preferably in the range of 〇4 to 4 00, more preferably in the range of 0. Within the range of 2 to 200, the best is at 0. 3 to 150 within the range. In the exit surface 6 of the light guide plate 1 provided in the surface light source element of the present invention, the ratio of W 3 to W 2 is maintained within these ranges, whereby the brightness of light emitted from the exit surface 6 of the light guide plate 1 is moderately maintained. And it is easy to set the conditions for obtaining an appropriate viewing angle. Here, when the ratio of W3 to W2 is in 〇. When it is within the range of 1 to 1 ,, the brightness in the straight direction can be improved. Further, when the ratio of (P-W2-W3) to (W2 + W3) is in the range of 0 · 3 to 150, the luminance in the straight direction can be suppressed from being lowered, and the viewing angle characteristics can be increased. on the other hand. In the bottom surface 7 of the light guide plate 具备 provided in the surface light source element of the present invention, the ridges 9 and the ridges 9' having a trapezoidal shape in cross section are placed in contact with each other and arranged parallel to the incident end surface 8 with W 3 being 0. By gradually adjusting the size of the ridges 9 of the trapezoidal shape, the amount of light emitted from the exit surface 6 can be adjusted to be -19-200817793. The cross-sectional shape of the ridges 9 of the trapezoidal shape formed on the bottom surface 7 of the light guide plate 1 is preferably set at an inclination angle a1 and an inclination angle a2 of 32. In the range of 5° to 4 5°, more preferably in the range of 35° to 45°, and most preferably at 37. 5°~42. Within 5°. The height is preferably set in the range of 1 // m to 1 μm, more preferably in the range of 5//m to 50//m, and most preferably in the range of l〇//m~20// Within the range of m. The width of the upper bottom is preferably set in the range of 3//m to 1600//m, more preferably in the range of 10//m to 800//m, and most preferably in the range of 15//m to 3 5 0 // in the range of m. The width of the lower bottom is preferably set in the range of 6 // m to 1800//m, more preferably in the range of i5//m to 1000//m, and most preferably in the range of 25/zm to 400// Within the range of m. [Description of Light Control Member] The light control member 11 of the present invention has a function of expanding the angle of view of the light emitted from the light guide plate 1 in the horizontal direction and focusing the angle of view in the vertical direction toward the front side. In the present invention, the light control member 11 is formed into a flat plate shape, a film shape, a panel shape or the like by a transparent resin or the like as shown in Fig. 1, and has a surface side (exit surface) on one of the main bodies 14 A specific ridge-like projection 15 formed at a predetermined distance. The ridge-like convex portion 15 is a convex pattern extending parallel to the X-axis, and the contour line 15 5 a parallel to the Y-Z plane has a curved portion including at least the top portion. This ridge-like convex portion 15 is in a form of being raised on an elongated straight line. Here, as shown in detail in FIG. 1, the angle Θ between the tangent line of the YZ plane and the Y-axis of the contour line 1 5 a is monotonously -20-200817793 centered on the apex of the convex portion. The range of increase is to satisfy the following formulas (1) and (π). 0. 45 Θ max ^ Θ 1 S〇. 750max ...Formula (I) 0. 25p SI Ymax | ···Formula (η) Here, 'Ymax is the position in the Y-axis direction when the θ is monotonically increasing from the origin as 0 max (distance from the origin to the γ-axis), that is, at Ymax The inclination of the tangent to the contour line 1 5 a is 0 ma X. Further, 0' is a case where Y' is set to 1 /2 of Y ma X, and the inclination of the contour line 1 5 a at the position of Y ' is γ axis, and the direction of the p-line contour 1 5 a is parallel to the Y-axis. Width (pitch). Thus, in the case where the contour line 15 a has an inflection point, γ m a X is the distance from the origin to the inflection point, and the inclination angle at this position is 0 max. Here, in the formula (I), Y means Y, and when it is 1/2 of Ymax, the shape of the contour line 1 5 a at the position of Y ' with respect to the Y-axis is 0. Therefore, in the formula (I), it means that the shape of the inclination angle 0 ′ of the contour line 1 5 a to the Y axis at the position of Y ′ at γ when γ is 1/2 is obtained. Further, in the formula (II), even in the case of the inflection point, the position Ymax is displayed as 1 / 4 of the pitch P, that is, the display is often located outside the one side 1 / 2 from the outline 1 5 a . Thereby, for example, only the light control sheet (the cymbal) in which the top is formed in a circular shape is not limited thereto. Further, this drawing is a description of the drawings, and although the inflection point is shown on the drawing, the inflection point may be absent as in the embodiment to be described later. [Explanation of the action] Next, a light guide plate having a pattern having mutually perpendicular ridges on the exit surface and the bottom surface facing the exit, and an exit side on the exit surface side of the light guide plate will be described. The combination of the light control sheet having a specific ridge-like convex portion - 21 - 1717793 improves the brightness of the front direction on the one hand and ensures the principle of the angle of view on the one hand. [Improvement of the vertical (upper and lower) directions] First, the angular luminance distribution of the light emitted from the light guide plate provided in the surface light source element of the present invention in the vertical direction (Y-axis direction) is shown in Fig. 6. In other words, Fig. 6 is an angular distribution diagram of the outgoing light emitted from the exit surface 6 in the case where the light control sheet shown by reference numeral 1 is not provided in Fig. 1. It is shown that the light emitted from the light guide plate 1 has a large distribution of the outgoing components in the vicinity of 45° in the front direction. Next, Fig. 7 is a view showing the direction in which a part of the light 1 2a incident in parallel with respect to the normal line of the incident surface 1 1 a of the light control sheet 11 is performed. In the seventh drawing, a part of the light 12a incident parallel to the normal line of the incident surface 11a of the light control sheet 11 passes through the incident surface and is refracted at the convex curved surface 15a, as indicated by the symbol 1 3 A. Shown, shot near the front direction. Next, Fig. 8 is a view showing the direction in which a part of the light 12b incident from the normal to the incident surface 11a of the light control sheet 11 is inclined (about 45°). In the eighth drawing, a part of the diaphragm 2b which is incident obliquely from the normal line of the incident surface 1 1 a of the light control sheet 11 is refracted at the incident surface 1 1 a and the convex curved surface 15 5 a as a symbol As shown by 1 3 B, it is emitted near the front direction, and the other portion is shown by the symbol 丨3C, and the total reflection is returned to the light guide plate 1. According to the present invention, the light emitted from the light guide plate 扩散 diffused in the vicinity of 45° in the vertical direction (Y-axis direction) is focused in the front direction, and the light emitted from the light plate 1 in the front direction is kept toward the front side. Directional shots are associated with an effective increase in brightness. In this manner, the angular luminance distribution of the light emitted from the surface light source element of the present invention in the vertical direction (the y-axis direction) of the light-transmitting light control -22-200817793 is shown in Fig. 9. [Improvement in the horizontal direction] Next, the angular luminance distribution of light emitted from the light guide plate provided in the surface light source element of the present invention in the horizontal direction (X-axis direction) is shown in Fig. 10. The light emitted from the light guide plate provided in the surface light source element of the present invention has a large distribution of components which are emitted in the front direction. When the convex portion of the light control sheet is disposed parallel to the X-axis direction and the surface light source element of the present invention is disposed with the X-axis as the horizontal direction, the light emitted from the light guide plate is incident on the incident surface and the convex surface of the light control sheet. The refractive, horizontal angular brightness distribution is emitted in a more dispersed direction with respect to the front direction. Therefore, when the light control member of the present invention is disposed on the exit surface side of the light guide plate in addition to the light guide plate of the present invention, the viewing angle in the horizontal direction is enlarged, and the viewing angle characteristics can be improved. Fig. 1 is a view showing the angular luminance distribution of light emitted from the surface light source element of the present invention in the horizontal direction. In other words, the light guide plate used in the present invention uses an edge light type surface light source element, and has a pattern for the convex surface of the exit surface and the convex strip facing the bottom surface to maintain a wide viewing angle. The feature, on the one hand, achieves high functionality. Further, the light control sheet supported on the light guide plate has a convex portion on the exit surface, and at least one incident end surface of the light guide plate is disposed parallel to the X axis, and the convex portion of the light control sheet is disposed parallel to the X axis, when the X axis is When the direction is set to the horizontal direction and the x-axis direction orthogonal to the X-axis is the up-down direction, the outgoing light 'from the light guide plate has an angle of view in the horizontal direction' and the upper and lower -23-200817793 are focused. And the function towards the front. Further, by using the light guide plate having the trapezoidal convex portion and the light control sheet, light absorption or light emission in an unnecessary direction can be reduced, so that the light utilization efficiency is improved, and energy saving can be achieved. The light guide plate provided in the surface light source device of the present invention is configured such that the light incident from the primary light source is switched and controlled in the direction of the exit surface by being arranged on the pattern of the ridges facing the bottom surface facing the exit. The amount of light emitted from the exit surface is controlled by the pattern of the ridges of the exit surface to control the light distribution. The convex portion of the light control sheet can obtain a high front luminance because the light emitted from the light guide plate can be efficiently directed toward the front surface. Further, the light emitted from the light control sheet is monotonously lowered in accordance with a wide angle from the front to the oblique direction, and the shape of the convex portion of the light control sheet is a smooth curved surface and is not easily injured. Therefore, it is not necessary to arrange the diffusion sheet on the exit surface side of the light control sheet in order to correct the luminance distribution of the emitted light and prevent the damage, and it is possible to achieve high production efficiency and low cost. Thereby, the convex portion of the light control sheet of the present invention is arranged parallel to the X-axis, and the light in the Y-axis direction can be focused to the front side, and has a function of widening the light parallel to the X-axis direction. In general, when a screen display device such as a monitor is used, a wide viewing angle is desired in the horizontal direction. Therefore, when the viewing angle is narrowed by the light control sheet and the light is concentrated in the front direction, it is preferable to collect the light in the horizontal direction as it is in the vertical direction. Since the convex portion of the light control sheet of the present invention is disposed parallel to the X-axis and the surface light source element of the present invention is disposed such that the X-axis direction is horizontal, the desired -24-200817793 can be effectively realized. Spotlight. The convex portion of the light control sheet satisfying such a condition, the inclination angle of the outline of the cross section parallel to the X-axis direction and parallel to the convex portion of the YZ plane formed by the Y-axis and the Z-axis, and the Y-axis must have The apex of the convex portion is a smooth curved surface in which the two directions in the center are monotonously increased. Thereby, the angle of the light which is refracted is also dispersed in the vicinity of the front surface, and the angular luminance distribution of the smooth outgoing light which is monotonously reduced in brightness from the front direction toward the oblique direction is obtained. Further, since the top portion has a curved surface, the top portion is less likely to be notched, and it is not necessary to place the diffusion sheet in order to prevent the injury, and high productivity can be obtained. Further, when the inclination angle 0 of the contour line to the Y-axis satisfies the above formula (I) and formula (II), the light emitted from the light guide plate can be effectively directed toward the front surface. When 0' is smaller than this range, the ratio of the light of the convex portion to the front surface becomes small, and when 0' is large, the light which is obliquely emitted from the front side is increased, and the light use efficiency is lowered. Further, the convex portion of the light control sheet is parallel to the X-axis direction, and the cross-sectional shape of the convex portion parallel to the YZ plane formed by the Y-axis and the Z-axis is formed by a part of an ellipse whose one end of the major axis of the ellipse is a vertex. The partial elliptical shape, and when the absolute entanglement of the tangential line of the partial elliptical shape with respect to the inclination angle of the Y-axis is in the range of 60° to 80°, the obliquely incident light is biased toward the front surface, and the luminance at the wide angle side can be reduced. Smooth angular distribution of brightness. Moreover, the ratio of the height h to the width p of the partial elliptical shape parallel to the Y-axis is determined by the maximum 値 of the inclination of the tangent of the local bridge circle shape and the aspect ratio of the top of the convex portion. When the ratio is in the range of 0 · 3 9 to 0 · 5 3 , the light incident in the front direction can be efficiently emitted toward the front side -25-200817793, so that higher light utilization efficiency can be obtained. Further, the convex portion of the light control sheet is parallel to the X-axis direction and is parallel to the cross-sectional shape of the convex portion of the Y-z plane formed by the Y-axis and the Z-axis, and is a partial parabola formed by a portion of the parabola including the apex of the parabola. The shape, the maximum tangent of the tangent of the partial parabola shape to the Y-axis is in the range of 52° to 62°, and the light incident in the oblique direction can be more biased toward the front direction. The ratio of the width p of the local parabolic shape parallel to the Y-axis is determined by the maximum 値 of the inclination of the tangent of the local parabolic shape, and when the maximum 値 of the inclination is in the range from 52° to 62°, the ratio Now at 0. 32 to 0. Within the range of 4 7 . Further, the light control sheet of the present invention can efficiently improve the front luminance of the surface light source element of the present invention. Moreover, compared with the cymbal, the convex portion is not easily injured, and a smooth light distribution can be obtained. Here, in the formula (I), the convex portion of the ridge shape of the exit surface of the light control sheet is preferably 0. 450 maxS (9 ’$0. 700 max. At this time, the light can be more effectively deflected toward the front direction, so that a high front luminance can be obtained. Also, preferably 0. 450 maxS 0’SO. 680, more preferably 0. 460 maxS Θ ’ S 0. 65 0 max. At this time, the light can be more effectively deflected toward the front side to obtain high front luminance and high luminance uniformity. In the present invention, the cross-sectional shape of the YZ plane of the convex portion of the light control sheet is, for example, a partial elliptical shape formed by a portion of an ellipse having one end of the minor axis of the ellipse as a vertex, or a parabola including a vertex of a parabola. A partial parabolic shape formed is preferred. When the convex portion of the light control sheet has a partial elliptical shape, 0 max is -26-200817793 from 63 ° to 80 °, and the aspect ratio is 〇 · 4 2 to 〇. 5 2 is preferred. At this time, the light efficiency is favorably biased to the front side, and high brightness uniformity can be obtained. Further, 'the case where the groove-shaped recessed portion in which the convex portion is inverted is used as the master mold for producing the convex portion' has a high production efficiency in order to increase the strength of the master mold, and 0 max is from 69 to 75 °, and the width is wide. The ratio is 0. 43 to 0. 48 is preferred. When the convex portion of the light control sheet has a partial parabola shape, 0 max is from 53° to 58°, and the aspect ratio is 0. 34 to 0. 43 is preferred. At this time, the light incident in the oblique direction can be concentrated toward the front direction, and high brightness uniformity can be obtained. Also, 0max is from 55° to 57. The aspect ratio is 〇·36 to 0. At 39 o'clock, it is better to obtain a higher frontal brightness. The width p of the convex portion of the light control sheet is preferably 1 / m to 500 # m. When it is larger than 5 Ο Ο /Z m , the pattern is visible from the exit surface, so the appearance quality is lowered. When it is less than 1 // m, it is colored due to the diffraction phenomenon, so that the appearance quality is lowered. More preferably 20//m~300//m, the best is 30//m~200#m. In this range, it is difficult to observe the pattern, and the production of the convex portion becomes easy and productive. In the present invention, although the thickness of the light control sheet is not limited, it is preferable to set the thickness of the light control sheet in consideration of the strength, productivity, and the like of the light control sheet itself. Although the thickness is different depending on the size of the surface light source component, it is 0. 05 // m~1mm is appropriate. When it is thinner than this, the quality is lowered due to the strength reduction, deformation, and the like of the light control sheet itself. Further, when it is thicker than this, the surface light source element becomes thicker and the weight also increases. Further, in order to prevent deformation due to heat of the light control sheet, etc., and to obtain productivity by extrusion molding or the like, it is at 0·1 mm to 0. 7mm is better, and again, at 0. 2mm~0. Better in the range of 5mm. -27-200817793 The manufacturing method of the light control sheet may be extrusion molding, injection molding, 2P molding, etc., but an appropriate molding method may be selected in consideration of the size of the convex portion, the shape of the convex portion, mass productivity, and the like. The short side and the long side of the main surface are all over 400 mm, etc. For large-scale surface light source components, extrusion molding is suitable. Further, in the case where the thickness is less than 1 mm, extrusion molding and 2P molding are suitable. Next, a modification of the surface light source element of the present invention will be described with reference to the drawings. First, in Fig. 4, the two linear light sources 4a on the opposite sides of the light guide plate 1 are used as the primary light source 4. The configuration of the large-sized liquid crystal image display device is shown as an example of the surface light source element 10 of the present invention. Here, the fourth (a) and (b) drawings are side views when viewed from the side parallel to the X-Z plane in the Y-axis direction, and side views when viewed from the side parallel to the Y-Z plane in the X-axis direction. The primary light source 4 is disposed on both sides of the exit surface 6 and the bottom surface 7, and a pair of linear light sources 4a are disposed in the reflector 4b. In order to sufficiently ensure the amount of light incident from the linear light source 4a into the light guide plate 1, a light guide plate 1 having a large thickness is used. Thereby, the two side faces of the primary light sources 4 are arranged as the incident end faces 8, and the two side faces that intersect the incident end faces 8 serve as the reflecting end faces 8b°, and the surface light source elements of FIG. 4 are disposed above the exit surface 6. There are a diffusion sheet 5 a and a light control sheet 11 of the present invention. The diffusion sheet 5a is disposed between the light guide plate 1 and the light control sheet 1 1 so that the light emitted from the surface light source element 10 can be appropriately uniformized to improve the quality. Also, the front brightness can be further improved by selecting an appropriate diffusion sheet -28-200817793 5a. In the surface light source element 1 of Fig. 4, the ridges 2 having a trapezoidal shape in cross section and the trapezoidal strips 3 having the trapezoidal shape of the ridges 2 which are vertically inverted are arranged alternately on the exit surface 6. These ridges 2 and 3 are substantially the same as the surface 1a of the trapezoidal shape of the ribs 2 shown in Figs. 1 and 2, and therefore detailed description thereof will be omitted. In this manner, a plurality of ridges and concave strips having a trapezoidal shape in cross section perpendicular to the incident end surface 8 are disposed on the exit surface 6. On the other hand, the ridges 9 having a trapezoidal shape in cross section are in contact with each other and are arranged in parallel on the bottom surface 7. By gradually adjusting the size of the ridges 9 of the trapezoidal shape, the light amount distribution of the light emitted from the exit surface 6 can be adjusted. The light of the linear light source 4a is incident on the light guide plate 1 from the incident end surface 8 of the light guide plate 1, and is totally reflected and finally propagated in the longitudinal direction between the exit surface 6 and the bottom surface 7. Thereafter, a part of the light is guided to the exit surface 6 by the ladder-shaped ridges 9 and the reflection sheets 5 formed on the bottom surface 7, and the cross section formed on the exit surface 6 is formed by a trapezoidal shape (protrusion 2 and concave) Strip 3) and collect the light to shoot into the desired angle of view. In this manner, by forming a prism having a trapezoidal shape in cross section on the exit surface 6, it is possible to suppress a decrease in luminance in the straight direction and to increase the viewing angle as compared with a case where a V-groove is formed on the exit surface 6. The material of such a light guide plate or light control sheet can be used as long as it is a usual optically transparent material. For example, a methacrylic resin, a polycarbonate resin, a cycloolefin resin, a polystyrene resin, a methacrylic acid-this ethylene-co-polymerization resin, and a smoke-bonding fine-copolymer resin are mentioned. These transparent -29- 200817793 resins have a value greater than 1. 4 refractive index. As the refractive index satisfying the conditions of the present invention, 1. 42 to 1. A range of 65 is preferred. Further, in order to further improve the uniformity of brightness, a light diffusing means may be provided in the light guide plate and/or the light control sheet provided in the surface light source device of the present invention. Examples of the light-diffusing means include a method of providing random irregularities such as embossing or bumps on the main surface of the light guide plate or the light control sheet, and a method of providing fine particles having a small amount of light inside the structure. A method of providing a diffusion sheet on the incident surface side and/or the emission surface side of the light guide plate or the light control sheet, or a method of combining these. The random concavities and convexities can be realized by applying a solution in which fine particles have been dispersed to a main surface by spraying or the like, extruding a resin in which fine particles have been dispersed, and transferring the formed mold by a concave-convex mold. The degree of the unevenness is preferably an arithmetic mean roughness R a of 3 // m or less. When it is larger than this, the diffusion effect becomes too large, so the front luminance is lowered. For example, as shown in Fig. 12(a), the trapezoidal shape pattern is an example in which the zenith surface (upper bottom) 2a and the inclined surface 2b are mirror surfaces, but the surfaces thereof may be roughened. For example, as shown in Fig. 12(c), when the inclined surface 2b of the trapezoidal ridge (the ridge 2) is roughened, the angle of view is enlarged as compared with the case where the mirror surface is completely shown in Fig. 12(a). Further, it is possible to achieve an improvement in surface quality such as a glare feeling of the surface light source element 1 and a dark line which is generated when the corner portion of the light guide plate is viewed obliquely. Further, as shown in Fig. 12(d), when the entire surface of the zenith surface 2a and the inclined surface 2b of the trapezoidal prism (the rib 2) is roughened, only the inclined surface 2b is shown in Fig. 12(c). Compared with the case of roughening, although the surface brightness is somewhat reduced by -30-200817793, it is possible to achieve a glare feeling as a surface light source element, or a surface quality of a dark line, etc., which is suitable for the viewing angle. And surface quality is considered an important surface light source component. Further, in the liquid crystal display device obtained in this manner, the surface quality is excellent. Such roughening, for example, the arithmetic mean roughness (Ra) of ns B 060 1 is 0. A range of 1//m to 10//m is preferred. More preferably at 0. 15// m~5 // m range, especially good for 〇. 2 # m~2 // within the range of m. Further, such a roughening, as shown in Fig. 12(b), can be performed only on the upper base (zenith surface) 2a of the ridge 2, but as shown in Fig. 12(d), Both the zenith surface 2a and the inclined surface 2b are implemented (full diffusion surface). Further, as shown in Fig. 12(c), it may be implemented only on the side surface portion (inclined surface 2b). Further, this roughening can also be carried out on the upper bottom (zenith surface) 3a of the concave strip 3. The diffusing surface is formed by roughening the surface, whereby the emitted light can be expected to have an improved surface quality in any case. Further, the image display device of the present invention is realized by providing a transmissive display device on the surface light source element, and a transmissive liquid crystal panel or the like is exemplified as the display device. Thereby, an image display device having high brightness on the display surface and excellent brightness uniformity can be obtained. In this case, the image display device of the transmissive display device is provided on the exit surface side of the surface light source element of the present invention, preferably 1/100 to 1/1 of the pixel pitch of the transmissive display device. 5. When it is larger than this, interference fringes between the pixels are generated to lower the appearance quality. EXAMPLES Hereinafter, the effects of the present invention will be specifically described by way of examples. -31- 200817793 (Example 1) A negative-type light IST of 1 (CA 3 0 00) manufactured by Tokyo Yinghua Industrial Co., Ltd. was applied to a clean glass to 'heat on a hot plate at 110 ° C. 2 After a minute, cool to room temperature. The glass substrate is brought into close contact with the photomask having slits at regular intervals to operate at a speed of from -5 5 ° to + 35 °° with 120 seconds, during which time 1 400 ml of UV is irradiated. Light. After the photomask was peeled off, the substrate was developed. The resulting master was formed into a conductive film on the surface in accordance with a conventional method. On the conductive film, ruthenium was used as an electrographic metal to perform electric prayer to form a patterned layer. Further, the original disk was peeled off from the conductive film to form a high degree of enthalpy. 〇imm has a flat portion having a width of about 10 // m at the top portion and a stamper I on the exit surface side of the trapezoidal pattern having an inclination angle of 5 5 °. On the other hand, a diamond cutter is used for cutting on a direct mold set to produce a top angle of 100° and a height of zero. A 01 mm V-shaped groove is used to directly electroform the cutting set to form a nickel electroformed layer. The original disc is peeled off and the shape is made to a height of 0. 01mm, the apex angle is 100°, and the dies are arranged at predetermined intervals on the bottom side of the stamper II. The stamper I and the stamper II are assembled as a transfer mold in the mold-fixing side chamber and the mold-movable side chamber of the injection molding machine, and the fineness for the display of the 17-inch display is obtained by the injection molding method. Light guide plate 1 (6 mm thick). The light guide plate 1 thus produced includes an exit surface in which the ridges having a trapezoidal cross-sectional shape are arranged at intervals, and a bottom surface in which the ridges having a trapezoidal cross-sectional shape are connected to each other. The trapezoidal convex shape of the exit surface has a height Η of 1 0 // -32-200817793 m, a top width W2 of l〇//m, a bottom width W1 of 24//m, and a trapezoidal convex shape height of the bottom surface. 10// m, the bottom angle a1 and a2 are 40°' and the lower bottom is gradually changed from 1 80 // m to 6 0 // m from the side of the cold cathode tube to the center. The sheet-like concave portion in which the ridge-shaped convex portion (pitch p80//m) of the light control sheet is reversed is continuously formed in parallel on the roll-shaped mold by cutting, and the formed roll shape is used. Mold, a methyl methacrylate-styrene copolymer resin having a refractive index of about 1.10% by weight of a styrene-butadiene rubbery copolymer (refractive index of 1. 54) Manufactured by extrusion molding. Here, the light control sheet 11 of the present embodiment is thick. 4mm, the cross-sectional shape of the convex portion of the Y-Z plane is in accordance with the following formula, and the coefficient of these is C = 3. 24xl0·2, K = -0. 44, hmax = 41. 7 〇 %m) = /2inax~ C¥2
此時，0 max : 79.3° Θ ， ： 36.6° P( = Ymax) : 80 // m Θ 5 / (9 max :0.462 高寬比 ：0.52 將此導光板1之兩端的入射端面配置成平行於X軸’ 沿著此入射端面使管面亮度39,000cd/m2(—定）之CCFL·光 源，如第5圖所示在左右各配設一對，在光源的背側配設 反射器。又，在導光板1之出射面上配設光控制片1 1 ’使 -33- 200817793 得光控制片1 1之壟狀凸部1 5與X軸成平行。 將反射片5(東麗股份有限公司E6SL)配設在底面7及 反射端面8b，以形成第5圖所示之背光裝置。測定依此方 式形成的背光裝置的亮度性能。此亮度測定係使用拓普康 股份有限公司製作的亮度計（TOPCON BM-7)，從樣本面離 開5 0cm而測定。又，求出背光面上之最低亮度對最大亮度 之比以作爲亮度不均。又，在導光板1之出射面中央點， 針對與成型於出射面的截面形狀爲梯形形狀的凸條之長邊 正交的垂直面，將亮度計從出射面筆直方向依序向兩側傾 斜來測定亮度之角度分布（此後稱爲水平方向角度亮度分 布）。同樣地，在導光板1之出射面中央點，針對與成型於 出射面的截面形狀爲梯形形狀的凸條之長邊平行，且垂直 於導光板1的面，將亮度計從出射面筆直方向依序向兩側 傾斜來測定亮度之角度分布（此後稱爲垂直方向角度亮度 分布）。由此水平方向角度亮度分布及垂直方向角度亮度分 布求出作爲視角特性指標的水平半値角及垂直半値角。 其結果，最大亮度爲4,785 cd/m2，亮度不均爲0.81， 水平半値角爲52.7°，垂直半値角爲38.7°。 (實施例2) 本實施例2係在使用於實施例1的導光板之出射面上 載設擴散片1片及光控制片1片之情況。 使與實施例1相同的導光板1之兩端的入射端面配置 成平行於X軸，沿著此入射端面使管面亮度39,000cd/m2( 一定）之CCFL光源，如第4圖所示在左右各配設一對，在 -34· 200817793 光源的背側配設反射器。又，在導光板1之出射面上配設 1片智積電（tsujiden)股份有限公司製之擴散片（商品名 :D124)5a，更在其上配設光控制片11(與在實施例1所用相 同之光控制片），使得壟狀凸部與X軸成平行。 將反射片5(東麗股份有限公司E6SL)配設在底面7及 反射端面8b，以形成第4圖所示之背光裝置。 以與實施例1相同的方法測定依此方式形成的背光裝 置的亮度性能，最大亮度爲5,070 cd/m2，亮度不均爲0.81 ，水平半値角爲51.8°，垂直半値角爲37.4°，亮度高且視角 特性亦良好。 (比較例1) 此比較例係在PMMA製之平板（板厚6mm)的底面上賦 予印刷點而製作導光板，在導光板之出射面側的平坦部上 載設擴散片1片及光控制片1片之情況。 在導光板之底面設置以離入光端面越遠越密的方式具 有疏密的白色印刷點（在導光板中央部的點密度大），將亮 度分布作成既定的分布。在此導光板的兩端沿著入光端面 配設光源，在光源的背側配設反射器4b ’在導光板之出射 面側的平坦部上配設1片智積電股份有限公司製之擴散片（ 商品名：D124)5a，更設置1片光控制片（與使用於實施例1 者爲相同的光控制片），使得其溝列相對於入光端面大致平 行，將反射片5(東麗股份有限公司E6SL)配設在底面及反射 端面，以形成第1 3圖所示之背光裝置。測定依此方式形成的 背光裝置的亮度性能，最大亮度爲4,398 cd/m2’亮度不均爲 -35- 200817793 0.79，水平半値角爲56.Γ，垂直半値角爲39.1°。 依此方式，即使在白色印刷點的導光板使用光控制片 ，亮度提高的效果亦低。 (比較例2) 此比較例係在使用於實施例1之導光板上載設擴散片 2片之情況。在與實施例1相同的導光板之平坦部上配設2 片智積電股份有限公司製之擴散片（商品名：DX2)5a，將反 射片5(東麗股份有限公司E6SL)配設在底面及反射端面， 以形成背光裝置。測定依此方式形成的背光裝置的亮度性 能，最大亮度爲4,7 66 cd/m2，亮度不均爲0.79，水平半値 角爲42.3°，垂直半値角爲42.Γ。 爲了消除亮度不均且提高筆直方向的亮度而使用2片 擴散片之情況，雖然藉由擴散片使光束向正面方向聚光， 但視角變窄且變成各向同性的角度亮度分布。 (比較例3) 此比較例係在比較例1中使用的PMMA製之平板（板厚 6mm)的底面上賦予印刷點，而在導光板之出射面側的平坦 部上載設光控制片（與實施例1使用者爲相同的光控制片）1 片之情況。 · 在已賦予該印刷點的導光板之兩端沿著入光端面配設 光源’在光源的背側配設反射器4b，在導光板之出射面側 的平坦部上設置1片光控制片，使得其溝列相對於入光端 面成爲大致平行，將反射片5(東麗股份有限公司E6SL)配 設在底面及反射端面，以形成背光裝置。測定依此方式形 -36- 200817793 成的背光裝置的亮度性能，最大亮度爲3,903 cd/m2，亮度 不均爲0.78，水平半値角爲69.2°，垂直半値角爲42.5°。 依此方式，即使在白色印刷點的導光板使用光控制片 ，從導光板射出的光亦無法充分地偏向正面方向，因此亮 度提高的效果和比較例1相比更低。 (比較例4) 此比較例係從滿足於本發明之光控制片的條件脫離之 情況。 此比較例之光控制片係藉由切削加工在滾筒狀模具使 光控制片的間距20 // m之壟狀凸部加以反轉之形狀的溝狀 凹部平行地連續而製作，使用上述滾筒狀模具，藉由已使 苯乙烯-丁二烯橡膠狀共聚合物約10重量％分散的甲基丙 烯酸甲酯-苯乙烯共聚合物樹脂（折射率1.54)擠出成型而製 作。 在此，本比較例之光控制片1 1係厚度爲〇.4mm，其凸 部之Y-Z平面的截面形狀係依照數式1，此等之係數爲 C 二 l.OOxlO·1、K = 0、hmax=10.0。此時，此凸部之 Y-Z 平面 的截面形狀成爲半圓形， Θ max :90·0〇 Θ ， ： 30.0° P( = Ymax) · 20 β m 0 ’係比下限値0.45 0 max = 40.5更小，而從滿足於本發 明之光控制片的條件脫離。 在使用於實施例1的導光板之平坦部上配設1片智積 -37- 200817793 電股份有限公司製之擴散片（商品名：DX2) ’更在其上配設 光控制片，使得光控制片之壟狀凸部與X軸成平行。將反 射片5(東麗股份有限公司E6SL)配設在底面及反射端面， 以形成第4圖所示之背光裝置。測定依此方式形成的背光 裝置的売度性能，最大売度爲4,816 cd/m2’売度不均爲0.81 ，水平半値角爲51.2°，垂直半値角爲37.2°。 與實施例2比較，由於該光控制片的凸部形狀使朝導 光板的回歸成分增大，且由於高出射角度成分的增大而降 低正面方向的亮度。 (比較例5) 此比較例係與從光控制部件的輪廓線之頂點的傾角單 調增加之情況相違者。即，與〇.25pS | Ymax丨之情況相違 ，從滿足於本發明之光控制片的條件脫離之情況。 本比較例之光控制片，係藉由切削加工在滾筒狀模具 使光控制片的間距20 // m之壟狀凸部加以反轉之形狀的溝 狀凹部平行地連續而製作，使用上述滾筒狀模具，藉由已 使苯乙烯-丁二烯橡膠狀共聚合物約1 0重量％分散的甲基 丙烯酸甲酯-苯乙烯共聚合物樹脂（折射率1.54)擠出成型而 製作。 在此，此比較例之光控制片1 1係厚度爲0 · 4 m m，其凸 部之Y-Z平面的截面形狀係爲高斯分布狀， I Y m a X I : 4 // m Θ max :68.0° θ ：42.3 -38- 200817793 P : 2 0 // mAt this time, 0 max : 79.3 ° Θ , : 36.6 ° P ( = Ymax ) : 80 // m Θ 5 / (9 max : 0.462 Aspect ratio: 0.52 The incident end faces of the both ends of the light guide plate 1 are arranged to be parallel to The X-axis 'CCFL light source with a tube surface brightness of 39,000 cd/m2 (--) along this incident end face is provided with a pair on the left and right as shown in Fig. 5, and a reflector is disposed on the back side of the light source. A light control sheet 1 1 ' is disposed on the exit surface of the light guide plate 1 such that the ridge-like convex portion 15 of the light control sheet 1 is parallel to the X axis. The reflection sheet 5 (Dongli Co., Ltd.) The company E6SL) is disposed on the bottom surface 7 and the reflective end surface 8b to form a backlight device as shown in Fig. 5. The brightness performance of the backlight device formed in this manner is measured. This brightness measurement is performed using the brightness produced by Topcon Co., Ltd. The measurement (TOPCON BM-7) was measured by leaving the sample surface at 50 cm. Further, the ratio of the lowest brightness to the maximum brightness on the backlight surface was determined as the brightness unevenness. Further, at the center point of the exit surface of the light guide plate 1, Luminance meter for a vertical plane orthogonal to the long side of the ridge formed in the trapezoidal shape of the exit surface The straight direction of the exit surface is inclined to both sides in order to measure the angular distribution of the luminance (hereinafter referred to as the horizontal angular luminance distribution). Similarly, at the center point of the exit surface of the light guide plate 1, the cross-sectional shape formed on the exit surface is The long sides of the trapezoidal shaped ribs are parallel and perpendicular to the surface of the light guide plate 1, and the luminance meter is measured by sequentially inclining the luminance meter from the straight direction of the exit surface to both sides (hereinafter referred to as a vertical direction angular luminance distribution). From the horizontal angular brightness distribution and the vertical angular brightness distribution, the horizontal half angle and the vertical half angle are obtained as the angle characteristics of the viewing angle. As a result, the maximum brightness is 4,785 cd/m2, the brightness is not 0.81, and the horizontal half angle is 52.7. °, the vertical half angle is 38.7°. (Embodiment 2) In the second embodiment, a diffusion sheet and a light control sheet are placed on the emission surface of the light guide plate of the first embodiment. 1 The incident end faces of the same light guide plate 1 are arranged parallel to the X axis, and the CCFL light source having a tube surface brightness of 39,000 cd/m 2 (certain) along the incident end face is as shown in Fig. 4 A pair of reflectors are provided on the right side of the light source, and a diffuser made of tsujiden Co., Ltd. (trade name) is placed on the exit surface of the light guide plate 1. :D124)5a, on which the light control sheet 11 (the same light control sheet as used in the embodiment 1) is disposed such that the ridge-like convex portion is parallel to the X-axis. The reflection sheet 5 (Dongli Co., Ltd.) E6SL) is disposed on the bottom surface 7 and the reflection end surface 8b to form a backlight device as shown in FIG. The luminance performance of the backlight device formed in this manner was measured in the same manner as in Example 1. The maximum luminance was 5,070 cd/m 2 , the luminance was not 0.81, the horizontal half angle was 51.8°, the vertical half angle was 37.4°, and the luminance was high. And the viewing angle characteristics are also good. (Comparative Example 1) In this comparative example, a light guide plate was formed by applying a printing dot to the bottom surface of a sheet made of PMMA (thickness: 6 mm), and a diffusion sheet and a light control sheet were placed on a flat portion on the exit surface side of the light guide plate. 1 case. The bottom surface of the light guide plate is provided with a dense white printed dot (large dot density in the central portion of the light guide plate) so as to be denser from the light incident end surface, and the brightness distribution is set to a predetermined distribution. A light source is disposed along the light incident end surface at both ends of the light guide plate, and a reflector 4b is disposed on the back side of the light source. A diffusion layer of the Chihiro Electric Co., Ltd. is disposed on the flat portion on the exit surface side of the light guide plate. A sheet (trade name: D124) 5a is further provided with one sheet of light control sheet (the same light control sheet as used in the embodiment 1) such that the groove row is substantially parallel with respect to the light incident end surface, and the reflection sheet 5 (east) E6SL) is disposed on the bottom surface and the reflective end surface to form a backlight device as shown in FIG. The luminance performance of the backlight device formed in this manner was measured, and the maximum luminance was 4,398 cd/m2', the luminance was not -35-200817793 0.79, the horizontal half-turn angle was 56.Γ, and the vertical half-turn angle was 39.1°. In this way, even if the light guide plate is used for the light guide plate of the white printed dot, the effect of improving the brightness is low. (Comparative Example 2) This comparative example was a case where two sheets of the diffusion sheet were placed on the light guide plate of Example 1. In the flat portion of the same light guide plate as in the first embodiment, two diffusion sheets (trade name: DX2) 5a manufactured by Chikaku Electric Co., Ltd. are disposed, and the reflection sheet 5 (Toray Co., Ltd. E6SL) is disposed on the bottom surface. And reflecting the end faces to form a backlight. The luminance performance of the backlight device formed in this manner was measured, and the maximum luminance was 4,7 66 cd/m2, the luminance was not 0.79, the horizontal half angle was 42.3, and the vertical half angle was 42. In order to eliminate luminance unevenness and increase the luminance in the straight direction and use two diffusion sheets, the light beam is concentrated in the front direction by the diffusion sheet, but the viewing angle is narrowed and becomes an isotropic angular luminance distribution. (Comparative Example 3) In this comparative example, a printing dot was applied to the bottom surface of a sheet made of PMMA (thickness: 6 mm) used in Comparative Example 1, and a light control sheet was placed on a flat portion on the exit surface side of the light guiding plate (and The case where the user of the first embodiment is the same light control sheet) is one piece. A light source is disposed along the light incident end surface at both ends of the light guide plate to which the printing dot is applied. A reflector 4b is disposed on the back side of the light source, and one light control sheet is disposed on the flat portion on the exit surface side of the light guide plate. The groove array is substantially parallel with respect to the light incident end surface, and the reflection sheet 5 (Toray Co., Ltd. E6SL) is disposed on the bottom surface and the reflection end surface to form a backlight. The brightness performance of the backlight device in the form of -36-200817793 was measured, and the maximum brightness was 3,903 cd/m2, the brightness was not 0.78, the horizontal half-turn angle was 69.2°, and the vertical half-turn angle was 42.5. In this manner, even if the light guide sheet is used for the light guide plate of the white printed dot, the light emitted from the light guide plate cannot be sufficiently deflected toward the front direction, so that the effect of improving the brightness is lower than that of Comparative Example 1. (Comparative Example 4) This comparative example was obtained from the condition that the light control sheet satisfying the present invention was separated. The light control sheet of this comparative example is produced by cutting a groove-shaped concave portion in which the shape of the ridge-shaped convex portion of the light control sheet having a pitch of 20 // m is reversed in parallel in the roll-shaped mold, and the above-mentioned drum shape is used. The mold was produced by extrusion molding a methyl methacrylate-styrene copolymer resin (refractive index: 1.54) in which a styrene-butadiene rubber-like copolymer was dispersed in an amount of about 10% by weight. Here, the light control sheet 11 of the comparative example has a thickness of 〇.4 mm, and the cross-sectional shape of the YZ plane of the convex portion is in accordance with the formula 1, and the coefficients of these are C 1.00×10·1, K = 0 , hmax = 10.0. At this time, the cross-sectional shape of the YZ plane of the convex portion becomes semicircular, Θ max : 90·0〇Θ , : 30.0° P (= Ymax) · 20 β m 0 ' is lower than the lower limit 値 0.45 0 max = 40.5 Small, and detached from the condition of the light control sheet satisfying the present invention. On the flat portion of the light guide plate used in the first embodiment, a diffusion sheet (trade name: DX2) manufactured by Chi-Chi-37-200817793 Electric Co., Ltd. is disposed, and a light control sheet is disposed thereon to enable light control. The ridge-like projections of the sheet are parallel to the X-axis. The reflection sheet 5 (Toray Co., Ltd. E6SL) was placed on the bottom surface and the reflection end surface to form a backlight device as shown in Fig. 4. The twist performance of the backlight device formed in this manner was measured, and the maximum twist was 4,816 cd/m2', the twist was not 0.81, the horizontal half-turn angle was 51.2, and the vertical half-turn angle was 37.2. In comparison with the second embodiment, the shape of the convex portion of the light control sheet increases the regression component toward the light guide plate, and the luminance in the front direction decreases due to the increase in the high exit angle component. (Comparative Example 5) This comparative example is in contradiction with the case where the inclination of the apex of the outline of the light control member is monotonously increased. That is, contrary to the case of 〇.25pS | Ymax丨, the condition that satisfies the light control sheet of the present invention is deviated. The light control sheet of the comparative example is produced by cutting a groove-shaped concave portion in which the shape of the ridge-shaped convex portion of the optical control sheet having a pitch of 20 // m is reversed in parallel by cutting in a roll-shaped mold, and the roller is used in parallel. The mold was produced by extrusion molding a methyl methacrylate-styrene copolymer resin (refractive index: 1.54) in which a styrene-butadiene rubber-like copolymer was dispersed in an amount of about 10% by weight. Here, the light control sheet 11 of this comparative example has a thickness of 0·4 mm, and the cross-sectional shape of the YZ plane of the convex portion is Gaussian, IY ma XI : 4 // m Θ max : 68.0 ° θ : 42.3 -38- 200817793 P : 2 0 // m
Ymax之絕對値係間距20 // m之1/4以下，從滿足於本發明 之光控制片的條件脫離。 在使用於實施例1的導光板之平坦部上配設1片智積 電股份有限公司製之擴散片（商品名：DX2)，更在其上配設 光控制片，使得上述光控制片之壟狀凸部與X軸成平行。 將反射片5(東麗股份有限公司E6SL)配設在底面及反射端 面，以形成第4圖所示之背光裝置。測定依此方式形成的 背光裝置的亮度性能，最大亮度爲4,5 3 3 cd/m2，亮度不均 爲0.80，水平半値角爲49.0°，垂直半値角爲37.3°。 測定垂直方向角度亮度分布，從相對於正面方向之高 出射角度被出射的光大幅地增大。因此與實施例2比較， 正面方向的亮度大幅地降低。 產業上之利用可行性 使用本發明之面光源元件具備的導光板及光控制片時 ，可將上下方向的視角聚焦，且使水平方向的視角擴大， 因此可高亮度化且改善視角特性，因此可合適地使用於面 光源元件。又，本發明之面光源元件係爲邊緣光方式，故 並未限定於裝設液晶背光裝置的監視器裝置，對筆記型電 腦、照明佈告板、交通標誌等之薄型的各種畫像顯示裝置 的應用亦可期待。 【圖式簡單說明】 第1圖是在組合本發明之面光源元件的光控制片之前 的分解示意圖、及說明突設於光控制片之出射面的壟狀凸 -39- 200817793 部之截面形狀之圖。 第2圖係顯示本發明之面光源元件之一例的示意圖。 第3圖是說明在使用於本發明之面光源元件的導光板 之出射面及底面上作爲圖案形成梯形形狀的示意圖。 第4(a)、（b)圖是顯示本發明之面光源元件的構成圖。 第5圖是顯示本發明之面光源元件的構成圖。 第6圖是來自本發明之面光源元件所具備之導光板的 上下方向之出射光的角度亮度分布。 第7圖是顯示對光控制片之入射面的法線平行地入射 之光的一部分之進行方向的圖。 第8圖是顯示對光控制片之入射面的法線傾斜地入射 之光的一部分之進行方向的圖。 第9圖是來自本發明之面光源元件之出射光的上下方 向的角度亮度分布圖。 第1〇圖是來自本發明之面光源元件所具備之導光板 的水平方向之出射光的角度亮度分布圖。 第11圖是是來自本發明之面光源元件之出射光在水 平方向的角度亮度分布圖。 第1 2圖是說明突設於本發明之面光源元件所具備之 導光板的出射面之梯形形狀的凸條之表面特性的圖。 第1 3圖是在施予印刷點之導光板的出射面上載置丨片 擴散片及1片光控制片之情況的構成圖。 第1 4圖是在施予白色點印刷之導光板上載置擴散片 、稜鏡片之面光源元件的上下方向之出射光的角度亮度分 -40- 200817793 布圖。 【主要元件符號說明】 1 導光板 2 凸條 3 凹條 4 一次光源 4a 線狀光源 4b 反射器 5 反射片 5 a 擴散片 6 出射面 7 底面 8 入射端面（側面） 8a 反射端面（側面） 8b 反射端面（側面） 9 梯形凸條 10 面光源元件 11 光控制片（光控制部件） 11a 入射面 12a 垂直於光控制片射入的光 12b 斜向於光控制片射入的光 13A， 13B 從光控制片射出的光 13C 在光控制片之壟狀凸部進行全反射的光 14 光控制片之本體 -41 - 200817793 15 15a 16 17 光控制片之壟狀凸部 凸部曲面（輪廓線） 在底面施以印刷點的導光板 印刷點The absolute 値 spacing of Ymax is 1/4 or less of 20 // m, which is deviated from the condition of the light control sheet satisfying the present invention. A diffusion sheet (trade name: DX2) manufactured by Chikaku Electric Co., Ltd. is disposed on the flat portion of the light guide plate used in the first embodiment, and a light control sheet is disposed thereon to make the light control sheet ridge. The convex portion is parallel to the X axis. The reflection sheet 5 (Toray Co., Ltd. E6SL) was disposed on the bottom surface and the reflection end surface to form a backlight device as shown in Fig. 4. The luminance performance of the backlight device formed in this manner was measured, and the maximum luminance was 4,5 3 3 cd/m 2 , the luminance unevenness was 0.80, the horizontal half-turn angle was 49.0°, and the vertical half-turn angle was 37.3°. The vertical direction angular luminance distribution is measured, and the light emitted from the exit angle with respect to the front direction is greatly increased. Therefore, the brightness in the front direction is greatly lowered as compared with the second embodiment. INDUSTRIAL APPLICABILITY When the light guide plate and the light control sheet provided in the surface light source element of the present invention are used, the viewing angle in the vertical direction can be focused and the viewing angle in the horizontal direction can be enlarged. Therefore, the brightness can be increased and the viewing angle characteristics can be improved. It can be suitably used for a surface light source element. Moreover, since the surface light source element of the present invention is an edge light type, it is not limited to a monitor device in which a liquid crystal backlight device is mounted, and is applied to various thin image display devices such as a notebook computer, a lighting signboard, and a traffic sign. I can also look forward to it. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an exploded perspective view showing a light control sheet of a surface light source element of the present invention, and a sectional shape of a ridge-shaped convex-39-200817793 portion which is projected from an exit surface of the light control sheet. Picture. Fig. 2 is a schematic view showing an example of the surface light source element of the present invention. Fig. 3 is a schematic view showing the trapezoidal shape formed as a pattern on the exit surface and the bottom surface of the light guide plate used in the surface light source element of the present invention. 4(a) and 4(b) are views showing the configuration of the surface light source element of the present invention. Fig. 5 is a view showing the configuration of a surface light source element of the present invention. Fig. 6 is an angular luminance distribution of the light emitted from the vertical direction of the light guide plate provided in the surface light source element of the present invention. Fig. 7 is a view showing a direction in which a part of light incident on the incident surface of the light control sheet is incident in parallel. Fig. 8 is a view showing a direction in which a part of light incident obliquely to the normal line of the incident surface of the light control sheet is made. Fig. 9 is an angular luminance distribution diagram of the upper and lower directions of the outgoing light from the surface light source element of the present invention. Fig. 1 is an angular luminance distribution diagram of light emitted from the horizontal direction of the light guide plate provided in the surface light source element of the present invention. Fig. 11 is a view showing the angular luminance distribution of the outgoing light from the surface light source element of the present invention in the horizontal direction. Fig. 1 is a view showing the surface characteristics of the trapezoidal ridges protruding from the exit surface of the light guide plate provided in the surface light source element of the present invention. Fig. 13 is a view showing a configuration in which a cymbal sheet diffusion sheet and a sheet of light control sheet are placed on the exit surface of the light guide plate to which the printing dot is applied. Fig. 14 is a diagram showing the angular brightness of the light emitted from the upper and lower directions of the surface light source element on the light guide plate to which the white dot printing is applied, and the surface of the light source element is -40-200817793. [Main component symbol description] 1 Light guide plate 2 Latlet 3 Recessed strip 4 Primary light source 4a Linear light source 4b Reflector 5 Reflective sheet 5 a Diffusion sheet 6 Exit surface 7 Bottom surface 8 Incident end surface (side surface) 8a Reflecting end surface (side surface) 8b Reflecting end face (side) 9 Ladder rib 10 Face light source element 11 Light control piece (light control part) 11a Incidence surface 12a Light 12b perpendicular to the light control piece is obliquely incident on the light control piece 13A, 13B The light emitted from the light control sheet 13C is totally reflected by the ridge-like convex portion of the light control sheet. 14 The light control sheet body -41 - 200817793 15 15a 16 17 The ridge-like convex portion convex surface of the light control sheet (outline) Light guide plate printing point with printed dots on the bottom