201235718 六、發明說明： 【發明所屬之技術領域】 本發明係關於-種導光板、面光源裝置及透過型圖像顯 示裝置。 【先前技術】 液晶顯示裝i等透過型圖像顯示纟置通常係酉己置於液晶 顯示面板等透過型圖像顯示部之背面側。透過型圖像顯示 裝置具有對透過型圖像顯示部供給背光之面光源裝置。作 為此種面光源裝置’已知有邊緣照明型之面光源裝置（例 如，參照專利文獻1)。 邊緣照明型之面光源褒i包括具有透光性之導光板及 配置於導光板之側方且用以對導光板之側面供給光之光 源。於導光板之背面侧，設置有用以使光反射之白點。於 該構成中’自光源輸出之光自與光源對向之導光板之側面 入射至導光板内。人射至導光板内之光於導光板内一面進 .行全反射一面傳播。於導光板之背面側，形成有複數個白 點（例如，參照專利文獻丨），因而由白點反射之光自導光板 之透過型圖像顯示部側之出射面出射。 先前，於透過型圖像顯示裝置中，為了將自導光板之出 射面出射之光沿正面方向聚光並使其高效地人射至透過型 圖像顯示部’而於導光板與透過型圖像顯示部之間配置有 禮鏡板》作為此種稜鏡板，有於透過型圖像顯示部側之面 並列配置有複數個稜鏡部而成者。 先前技術文獻 161699.doc 201235718 專利文獻 專利文獻1:曰本專利特開2005-38768號公報 【發明内容】 發明所欲解決之問題 • 然而’對於具有白點之導光板，於如上所述於導光板之 . 相反側之面配置形成有稜鏡部之稜鏡板之情形時，無法充 分地謀求正面方向之亮度之提高。 因此，本發明之目的在於提供一種可謀求正面方向之亮 度之提高之導光板以及包含該導光板之面光源裝置及透過 型圖像顯示裝置。 解決問題之技術手段 本發明之導光板係設置於包含形成於單面之複數個稜鏡 部之與上述單面相反之側即背面側者，複數個上述稜鏡部 之各者沿一方向延伸，且複數個稜鏡部沿與稜鏡部之延伸 方向大致正交之方向並列配置。該導光板包括：位於稜鏡 部側之第1面，位於第1面之相反側之第2面，與第i及第2 面交叉且入射光之入射面，以及形成於第2面且向第丨面之 相反側凸出之複數個透鏡部。複數個透鏡部之各者具有出 • 射光之第2光量相對於第1光量之比大於〇·252%之外形，上 • 述出射光為自入射面入射且自第1面出射之光；第丨光量為 自第1面之一點出射之總出射光之每單位時間之量，第2光 量為自上述一點向特定區域出射之出射光之每單位時間之 量，特定區域具有25。以上35。以下之相對於第1面之法線 之角度範圍，並且相對於與上述棱鏡部之延伸方向大致正 161699.doc 201235718 交之方向具有±5。之圍繞法線之角幅。 本發明之面光源裝置係對包含形成於單面之複數個梭鏡 部之稜鏡板之與上述單面相反之側之面供給光者，上述稜 鏡板，複數個上述稜鏡部之各者沿一方向延伸，且複數個 稜鏡部沿與稜鏡部之延伸方向大致正交之方向並列配置。 面光源裝置包括：（1)導光板，其包括：（la)板狀之本體 部’該板狀之本體部具有位於稜鏡部側之第1面、位於第i 面之相反側之第2面、以及與第1及第2面交又且入射光之 入射面；及（lb)複數個透鏡部，該複數個透鏡部形成於第2 面’且向第1面之相反側凸出；以及（2)光源部，其配置於 導光板之入射面之側方且對入射面供給光。複數個透鏡部 之各者具有出射光之第2光量相對於第丨光量之比大於 0.2 5 2%之外形，該出射光為自入射面入射且自第丨面出射 之光；第1光量為自第1面之一點出射之總出射光之每單位 時間之量’第2光量為自上述一點向特定區域出射之出射 光之每單位時間之量，特定區域具有25。以上35。以下之相 對於第1面之法線之角度範圍，並且相對於與上述稜鏡部 之延伸方向大致正交之方向具有±5。之圍繞法線之角幅。 又，本發明之透過型圖像顯示裝置包括：（A)稜鏡板， 其包含形成於單面之複數個稜鏡部，複數個上述稜鏡部之 各者沿一方向延伸，且複數個稜鏡部沿與稜鏡部之延伸方 向大致正交之方向並列配置；（B)導光板，其相對於稜鏡 板而設置於單面之相反側即背面側，且包括：（B1)板狀之 本體部，該板狀之本體部具有位於稜鏡部側之第丨面、位 I61699.doc 201235718 於第1面之相反侧之第2面、以及與第丨及第2面交又且入射 光之入射面，及（B2)複數個透鏡部，該複數個透鏡部形成 於第2面，且向第i面之相反側凸出；（c)光源部，其設置 於導光板之入射面之側方且對入射面供給光；以及（〇)透 過型圖像顯示部，其設置於稜鏡板之單面側，藉由自稜鏡 板出射之光照明而顯示圖像。複數個透鏡部之各者具有出 射光之第2光量相對於第！光量之比大於〇 252%之外形，上 述出射光為自入射面入射且自第丨面出射之光；第丨光量為 自第1面之一點出射之總出射光之每單位時間之量第2光 里為自上述一點向特定區域出射之出射光之每單位時間之 量，特定區域具有25。以上35。以下之相對於第1面之法線 之角度範圍，ϋ且相對於與上述稜鏡部之延伸方向大致正 交之方向具有±5。之圍繞法線之角幅。 以下，於稜鏡板中將與導光板對向之面（上述單面之相 反側之面）稱作背面。 於上述構成之導光板、面光源裝置及透過型圖像顯示裝 置中’自導光板之人射面人射之光於導光板内—面進行全 反射-面傳播。若於導光板内傳播之光入射至設置於第2 面上之透鏡部’則於導歧内傳播之光藉由透鏡部而在與 全反射條件不同之條件下反射。由此，由透鏡部反射之光 自本體部之第1面出射。如此自第1面出射之光因形成於第 2面之複數個透鏡部之各者形成為滿足上述條件之形狀， 故易於以25。以上35。以下之範圍之出射角出射。導光板係 設置於上述稜鏡板之背面側，因而自導光板出射之光自棱 161699.doc 201235718 鏡板之背面入射至稜鏡板。向稜鏡板之光之入射角與來自 導光板之光之出射角大致相等。由此，來自第1面之出射 光之向稜鏡板之入射角易成為25。以上35。以下之範圍。以 此種入射角入射之光於自稜鏡部出射時，更多地沿正面方 向出射。其結果’正面方向之亮度提高。而且，本發明之 透過型圖像顯示裝置中，棱鏡板上設置有透過型圖像顯示 部’因而可以正面方向之亮度更高之光照明透過型圖像顯 示部。其結果’可謀求由透過型圖像顯示部顯示之圖像之 亮度提高。 發明之效果 根據本發明’可提供一種能謀求正面方向之亮度之提高 之導光板以及包含該導光板之面光源裝置及透過型圖像顯 示裝置。 【實施方式】 以下’參照圖式對本發明之實施形態進行說明。於圖式 之說明中，對相同要素標註相同符號，並省略重複之說 明。圖式之尺寸比率不一定與說明之内容一致。 圖1係表不應用本發明之導光板之一實施形態之透過型 圖像顯示裝置之概略構成之模式圖。於圖丨中，分解表示 出透過型圖像顯示裝置10之剖面構成。於圖i中，光係作 為光線而模式性地表示。透過型圖像顯示裝置10可較佳地 用作行動電活或各種電子機器之顯示裝置、電視裝置。 透過型圖像顯示裝置1G包括透過型圖像顯示部20、輸出 用以向透過型圆像顯示部20供給之面狀之光之面光源裝置 161699.doc 201235718 30、及配置於透過型圖像顯示部2〇與面光源裝▼ 30之間之 稜鏡板40。以下’為了便於說明，如圖i所示，相對於面 光源裝置30，將排列有稜鏡板40及透過型圖像顯示部2〇之 方向稱作Z方向或正面方向。將與z方向正交之2個方向稱 作X方向及Y方向。X方向及γ方向正交。 透過型圖像顯示部20由自導光板50出射之面狀之光照明 而顯示圖像。透過型圖像顯示部2〇之例為於液晶單元21之 兩面配置有直線偏光板22、23之作為偏光板貼合體之液晶 顯示面板。於該情形時’透過型圖像顯示裝置1〇為液晶顯 示裝置（或液晶電視）。液晶單元21及偏光板22、23可使用 先前之液晶顯示裝置等透過型圖像顯示裝置中所使用者。 液日日皁元21之例為TFT( thin film transistor，薄膜電晶體） 型之液b日單元或STN(Super Twisted Nematic，超扭轉向列） 型之液晶單元等》 稜鏡板40用以將自導光板5〇出射之光向正面方向聚光。 棱鏡板40為複數個稜鏡部41形成於透過型圖像顯示部2〇侧 之單面即表面40a之光學薄片。稜鏡板4〇之俯視形狀為大 致矩形狀。 稜鏡部41沿一方向（於圖丨中為γ方向）延伸。複數個稜鏡 部41於稜鏡部41之延伸方向上並列配置。稜鏡部41呈三稜 柱狀，與稜鏡部41之延伸方向正交之剖面之形狀為頂角以 呈大致直角之直角二角形。頂角〇只要為8〇〇以上丨〇〇〇以下 之範圍内之角度即可。頂角α更佳為8〇0以上9〇0以下，進 而較佳為90。。稜鏡部4 1之剖面形狀較佳為直角等腰三角 161699.doc 201235718 形。稜鏡部41之頂部4la之形狀亦可為因製造誤差等而產 生之程度之彎曲形狀。 稜鏡板40包含透光性材料（或透明材料）。透光性材料之 折射率之例為1.46〜1.62。透光性材料之例為透光性樹脂 材料、透光性玻璃材料。透光性樹脂材料之例為聚碳酸酯 樹脂（折射率：1.59)、MS樹脂（甲基丙烯酸甲酯-苯乙烯共 聚物樹脂 ’ methyl methacrylate-styrene copolymer resin)(折射率：1.56〜1.59)、聚苯乙烯樹脂（折射率： 1.59)、AS樹脂（丙烯腈-苯乙烯共聚物樹脂，acryi〇nitrile· styrene copolymer resin)(折射率：ι·56〜1.59)、丙烯酸系 紫外線硬化樹脂（折射率：丨46〜1 58)、聚甲基丙烯酸甲 0 曰（PMMA，polymethyl methacrylate)(折射率：1.49)等。 於棱鏡板40上，只要為不損害棱鏡板4〇之聚光功能之程 度，則亦可添加有擴散劑等。稜鏡板4〇之背面4〇b通常為 平滑之面。然而，背面40b亦可為具有不會顯著地損害稜 鏡板40之聚光功能之程度之粗糙度的粗面。於背面4〇b為 上述之粗面之情形時，例如，於稜鏡板4〇與導光板5〇之間 配置有另一光學構件之情形’可防止該光學構件與稜鏡板 40之相互黏附。 稜鏡板40之厚度可為稜鏡部41之頂部41&與稜鏡板4〇之 大致平坦之背面40b(表面4〇a之相反側之面）之間之距離。 植鏡板40之厚度之例為〇 ! mm以上5 mm以下。 面光源裝置30為對透過型圖像顯示部2〇供給背光之邊緣 照明型之背光單元。面光源裝置3〇包括導光板5〇、以及配 161699.doc •10· 201235718 置於導光板50之彼此對向之側面50a及側面5〇b之側方的光 源部60、60。 光源部6 0、6 0具有排列成線狀（於圖1中，沿γ方向排列） 之複數個點狀光源61。點狀光源61之例為發光二極體。為 - 了將光咼效地入射至導光板50 ’光源部6〇亦可於導光板5〇 • 之相反側，具備作為使光反射之反射部之反射器，此處， 例示出具有複數個點狀光源61之光源部6〇，光源部6〇亦可 為螢光燈等線狀光源。 面光源裝置30亦可具備相對於導光板5〇而位於透過型圖 像顯示部20之相反侧之反射部70。反射部7〇係用以使自導 光板50出射至反射部70側之光再次入射至導光板5〇者。反 射部70可如圖1所示為薄片狀。反射部7〇為收容導光板％ 之面光源裝置30之框體底面，亦可為實施鏡面加工之底 面。 參照圖1及圖2,對導光板50進行說明。圖2係自背面側 觀察圖1所示之導光板50之情形時之平面圖。導光板5〇之 俯視形狀可為大致矩形。 導光板50包括板狀之本體部51、及形成於本體部51之複 數個透鏡52。本體部51包含透光性材料（或透明材料）。 • €光性材料之折射率之例為146〜i仏透光性材料之例 為透光性樹脂材料、透光性玻璃材料。透光性樹脂材料之 •i為聚碳酉文g曰树脂（折射率：i 59)、⑽樹脂（甲基丙稀酸 y酉曰-本乙稀共聚物樹脂）(折射率：【义叫Μ)、聚苯乙烯 树月曰（折射率.i.59)、AS樹脂（丙稀腈-苯乙稀共聚物樹 161699.doc -11 - 201235718 脂）（折射率：1.56〜1.59)、丙烯酸系紫外線硬化樹脂（折射 率：1.46〜1.58)、聚甲基丙烯酸曱酯（PMMA)(折射率： 1.49)等。作為透光性樹脂材料，自透明性之觀點而言更佳 為 PMMA。 如圖1所示，本體部51包括於板厚方向上彼此對向之出 射面（第1面）5 la、及背面（第2面）5 lb。出射面51 a及背面 51b大致平坦。本體部51包括與出射面51 a及背面51b交又 之4個側面51c、51d、51e、51f。於圖1中，表示有於X方 向上彼此對向之2個側面5 1 c及5 1 d。側面5 1 c及側面51 d亦 為與光源部60對向之上述側面50a及側面50b。本體部51所 具有之4個側面5 1 c、5 1 d、5 1 e、5 1 f中剩餘2個側面5 1 e、 5 1 f(參照圖3)於Y方向上彼此對向》於圖1中，作為側面5 i c 及側面51d與出射面51 a及背面51b之配置關係之一例，表 示有側面51c及側面51 d大致與出射面51a及背面51b正交之 狀態。於本實施形態中，對本體部51之其他側面51e、51f 亦與出射面51 a及背面51b正交之形態進行說明。 如圖1及圖2所示’複數個透鏡部52形成於背面511)上。 透鏡部52係透明，用以將於導光板5〇内傳播之光自出射面 5 la側出射者。各透鏡部52之外形形狀為圓頂狀。 對各透鏡部52之形狀進行說明。為了說明之簡化，對複 數個透鏡部52之大小相同之形態進行說明。 透鏡部52具有如下之外形形狀：於自出射面5u上之任 意點（一點）？出射光之情形時，自出射位置即點p出射之第2 光量相對於第1光量之比（比率）大於0.252%。第！光量為自 161699.doc -12- 201235718 點P出射之總出射光之每單位時間之量。第2光量為自點p 向特定區域出射之出射光之每單位時間之量。上述特定區 域為如下區域’即，點p處之相對於出射面5 la之法線之角 度之範圍為2 5。以上3 5。以下，且圍繞法線之角幅以X方向 作基準為±5。。參照圖3對透鏡部52之形狀更具體地進行說 明。 圖3係用以說明透鏡部52之形狀之圖式。圖3(a)係表示出 射面5 1 a上之局部之座標系之設定狀態之圖式。圖3(b)係用 以說明自圖3(a)所示之座標系中之z軸及乂轴算起之角度之 規定方法的圖式。圖3〇)係用以說明特定區域之圖式。 如圖3(a)所示設定以出射面5 i a上之任意點p作為原點之 局部之xyz座標系，假定以原點為中心之單位球。於xyz座 標系中Z轴與出射面51a正交。即，z軸之軸線對應於出射 面51a之法線。X轴大致平行於χ方向。即，χ軸為大致與作 為入射面之側面51c、51d正交之方向。於該情形時，^軸 與Y方向大致一致^ X軸、y軸及2軸對應於χ方向、γ方向 及Ζ方向之情況於圖3(b)及圖3(c)中亦相同。 如圖3(b)所示，將自點p出射之出射光之方向與2軸之間 所形成之角度（偏角）設為θ，將出射光之方向與χ軸所形^ 之角度（偏角）設為卜於該設定中，點ρ處之相對於出射面 51a之法線之角度之範圍對應於自2軸之偏角即㊀之角戶範 圍，圍繞法線之角幅對應於0所滿足之角度範圍之角巾:： 進而’將於0。寝90。且〇。“咖。之範圍(圖3所示：球 之上半球）内出射之所有光之每單位時間之量即第i光量讯 16l699.doc -13· 201235718 為Qi ’將如圖3(c)所示，於作為25°$θ$35。且-5。$0$5〇 之範圍之特定區域（圖3所示之球之表面之影線區域）内出射 之光之每單位時間之量即第2光量設為Q厂又，將光量Q2 相對於光量Q】之比即光量比設為q(=q2/qiX1〇〇)(%)。 此時，透鏡部52之外形形狀為滿足201235718 VI. Description of the Invention: [Technical Field] The present invention relates to a light guide plate, a surface light source device, and a transmissive image display device. [Prior Art] A transmissive image display device such as a liquid crystal display device is usually placed on the back side of a transmissive image display unit such as a liquid crystal display panel. The transmissive image display device has a surface light source device that supplies backlight to the transmissive image display unit. For this type of surface light source device, an edge illumination type surface light source device is known (for example, see Patent Document 1). The edge illumination type surface light source 褒i includes a light-transmitting light guide plate and a light source disposed on the side of the light guide plate for supplying light to the side surface of the light guide plate. On the back side of the light guide plate, a white point for reflecting light is provided. In this configuration, the light output from the light source enters the light guide plate from the side surface of the light guide plate facing the light source. The light that is emitted into the light guide plate by one person enters the light guide plate and propagates on the side of the total reflection. A plurality of white spots are formed on the back side of the light guide plate (for example, see Patent Document ,), and light reflected by the white dots is emitted from the exit surface of the light guide type image display unit side of the light guide plate. In the transmission type image display device, in order to condense light emitted from the exit surface of the light guide plate in the front direction and efficiently radiate it to the transmissive image display portion 'on the light guide plate and the transmission pattern A mirror plate is disposed between the display portions, and the plurality of crotch portions are arranged side by side on the side of the transmissive image display unit. Prior Art Document 161699.doc 201235718 Patent Document Patent Document 1: Japanese Patent Laid-Open No. Hei. No. 2005-38768 SUMMARY OF THE INVENTION Problems to be Solved by the Invention • However, for a light guide plate having a white point, as described above, In the case where the surface of the opposite side is arranged with the seesaw of the crotch portion, the brightness in the front direction cannot be sufficiently improved. Accordingly, it is an object of the present invention to provide a light guide plate and a surface light source device and a transmissive image display device including the light guide plate which can improve the brightness in the front direction. Means for Solving the Problem The light guide plate of the present invention is provided on a side of a plurality of crotch portions formed on one side opposite to the one side, that is, a back side, and each of the plurality of crotch portions extends in one direction And the plurality of crotch portions are arranged side by side in a direction substantially orthogonal to the extending direction of the crotch portion. The light guide plate includes a first surface on the side of the crotch portion, a second surface on the opposite side of the first surface, an incident surface that intersects the i-th and second surfaces, and is incident on the second surface, and is formed on the second surface. a plurality of lens portions protruding from opposite sides of the second side. Each of the plurality of lens portions has a shape in which the ratio of the second light amount of the emitted light to the first light amount is larger than 〇·252%, and the above-described outgoing light is light that is incident from the incident surface and is emitted from the first surface; The amount of light is the amount per unit time of the total outgoing light emitted from one point of the first surface, and the second amount of light is the amount per unit time of the outgoing light that is emitted from the point to the specific area, and the specific area has 25. Above 35. The following angular range with respect to the normal to the first surface is ±5 with respect to the direction perpendicular to the direction in which the prism portion extends substantially 161699.doc 201235718. It is around the corner of the normal. The surface light source device according to the present invention supplies light to a surface of a side plate including a plurality of shuttle mirror portions formed on one side opposite to the one surface, and the plurality of sides of the plurality of the top portions The first direction extends, and the plurality of crotch portions are arranged side by side in a direction substantially orthogonal to the direction in which the crotch portion extends. The surface light source device includes: (1) a light guide plate including: (1) a plate-shaped main body portion. The plate-shaped main body portion has a first surface on the crotch portion side and a second surface on the opposite side of the i-th surface a surface, and an incident surface that is incident on the first and second surfaces and incident on the light; and (lb) a plurality of lens portions formed on the second surface and protruding toward the opposite side of the first surface; And (2) a light source unit disposed on a side of the incident surface of the light guide plate and supplying light to the incident surface. Each of the plurality of lens portions has a shape in which the ratio of the second light amount of the emitted light to the third light amount is more than 0.252%, and the emitted light is light that is incident from the incident surface and is emitted from the second surface; the first light amount is The amount per unit time of the total outgoing light emitted from one point of the first surface 'the second light amount is the amount per unit time of the outgoing light emitted from the one point to the specific area, and the specific area has 25. Above 35. The angle range with respect to the normal to the first surface is ±5 with respect to the direction substantially orthogonal to the direction in which the crotch portion extends. It is around the corner of the normal. Further, the transmissive image display device of the present invention comprises: (A) a seesaw including a plurality of crotch portions formed on one side, each of the plurality of crotch portions extending in one direction, and a plurality of ribs The mirror portion is arranged side by side in a direction substantially perpendicular to the direction in which the crotch portion extends; (B) the light guide plate is disposed on the opposite side of the single side, that is, the back side, with respect to the seesaw, and includes: (B1) a plate shape In the main body portion, the plate-shaped main body portion has a second surface on the side of the crotch portion, a second surface on the opposite side of the first surface of the position I61699.doc 201235718, and an incident light incident on the second and second sides And (B2) a plurality of lens portions formed on the second surface and protruding toward the opposite side of the i-th surface; (c) the light source portion disposed on the incident surface of the light guide plate Light is supplied to the incident surface on the side, and a transmissive image display portion is provided on one side of the seesaw, and an image is displayed by illumination from the light emitted from the seesaw. Each of the plurality of lens portions has a second amount of light emitted relative to the first! The ratio of the amount of light is larger than the shape of 〇252%, and the emitted light is light that is incident from the incident surface and is emitted from the second surface; the amount of the first light is the amount per unit time of the total outgoing light that is emitted from one point of the first surface. The light is the amount of time per unit time of the outgoing light that is emitted from the above point to a specific area, and the specific area has 25. Above 35. The following angular range with respect to the normal to the first surface is ±5 with respect to a direction substantially orthogonal to the direction in which the crotch portion extends. It is around the corner of the normal. Hereinafter, the surface facing the light guide plate (the surface opposite to the one side of the single surface) in the fascia plate is referred to as a back surface. In the light guide plate, the surface light source device, and the transmissive image display device having the above configuration, the light emitted from the human face of the light guide plate is totally reflected-surface-transmitted in the light guide plate. When the light propagating in the light guide plate is incident on the lens portion provided on the second surface, the light propagating in the guide is reflected by the lens portion under conditions different from the total reflection condition. Thereby, the light reflected by the lens portion is emitted from the first surface of the body portion. Since the light emitted from the first surface is formed into a shape satisfying the above conditions by the plurality of lens portions formed on the second surface, it is easy to be 25. Above 35. The exit angle of the following range is emitted. The light guide plate is disposed on the back side of the above-mentioned seesaw, so that light emitted from the light guide plate is incident on the seesaw from the back surface of the mirror plate 161699.doc 201235718. The angle of incidence of the light toward the raft is substantially equal to the angle of exit of the light from the light guide. Thereby, the incident angle of the outgoing light from the first surface to the raft is easily 25 . Above 35. The following range. When the light incident at such an incident angle exits from the crotch portion, it is emitted more in the front direction. As a result, the brightness in the front direction is improved. Further, in the transmissive image display device of the present invention, the transmissive image display portion is provided on the prism plate, so that the transmissive image display portion can be illuminated by the light having a higher brightness in the front direction. As a result, the brightness of the image displayed by the transmissive image display unit can be improved. Advantageous Effects of Invention According to the present invention, a light guide plate capable of improving the brightness in the front direction, a surface light source device including the light guide plate, and a transmissive image display device can be provided. [Embodiment] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and the repeated description is omitted. The dimensional ratio of the schema is not necessarily consistent with the description. Fig. 1 is a schematic view showing a schematic configuration of a transmissive image display device of an embodiment in which a light guide plate of the present invention is not applied. In the figure, the decomposition shows the cross-sectional configuration of the transmissive image display device 10. In Figure i, the light system is schematically represented as light. The transmissive image display device 10 can be preferably used as a display device or a television device for mobile electric activities or various electronic devices. The transmissive image display device 1G includes a transmissive image display unit 20, a surface light source device 161699.doc 201235718 30 that outputs planar light for supply to the transmissive circular image display unit 20, and a transmissive image. The seesaw 40 between the display unit 2〇 and the surface light source mounting ▼ 30. Hereinafter, for convenience of explanation, as shown in Fig. 1, the direction in which the seesaw 40 and the transmissive image display unit 2 are arranged with respect to the surface light source device 30 is referred to as a Z direction or a front direction. The two directions orthogonal to the z direction are referred to as the X direction and the Y direction. The X direction and the γ direction are orthogonal. The transmissive image display unit 20 illuminates the surface light emitted from the light guide plate 50 to display an image. In the example of the transmissive image display unit 2, a liquid crystal display panel as a polarizing plate bonding body in which the linear polarizing plates 22 and 23 are disposed on both surfaces of the liquid crystal cell 21 is used. In this case, the transmissive image display device 1 is a liquid crystal display device (or a liquid crystal television). As the liquid crystal cell 21 and the polarizing plates 22 and 23, a user of a transmissive image display device such as a liquid crystal display device of the prior art can be used. The example of the liquid daily soap element 21 is a TFT (thin film transistor) type liquid b day unit or an STN (Super Twisted Nematic) type liquid crystal cell, etc. The light emitted from the light guide plate 5 converges in the front direction. The prism sheet 40 is an optical sheet in which a plurality of crotch portions 41 are formed on one surface of the transmissive image display unit 2, that is, the surface 40a. The top view of the seesaw 4 is generally rectangular. The crotch portion 41 extends in one direction (in the direction of γ in the figure). A plurality of jaws 41 are arranged side by side in the direction in which the jaws 41 extend. The crotch portion 41 has a triangular prism shape, and the shape of the cross section orthogonal to the extending direction of the crotch portion 41 is a vertex angle at a right angle to a right angle. The apex angle 〇 is only required to be within an angle of 8 〇〇 or more. The apex angle α is more preferably 8 〇 0 or more and 9 〇 0 or less, and further preferably 90. . The cross-sectional shape of the crotch portion 4 1 is preferably a right-angled isosceles triangle 161699.doc 201235718 shape. The shape of the top portion 4la of the crotch portion 41 may be a curved shape to a degree that is caused by a manufacturing error or the like. The seesaw 40 contains a light transmissive material (or a transparent material). An example of the refractive index of the light transmissive material is 1.46 to 1.62. Examples of the light transmissive material are a translucent resin material and a translucent glass material. Examples of the light transmissive resin material are polycarbonate resin (refractive index: 1.59), MS resin (methyl methacrylate-styrene copolymer resin) (refractive index: 1.56 to 1.59), Polystyrene resin (refractive index: 1.59), AS resin (acrylonitrile-styrene copolymer resin, acryi〇nitrile styrene copolymer resin) (refractive index: ι·56 to 1.59), acrylic ultraviolet curable resin (refractive index : 丨 46~1 58), polymethyl methacrylate (PMMA, refractive index: 1.49), and the like. The prism plate 40 may be provided with a diffusing agent or the like as long as it does not impair the light collecting function of the prism plate 4. The back of the fascia 4〇4〇b is usually a smooth surface. However, the back surface 40b may also be a rough surface having a roughness that does not significantly impair the concentrating function of the prism sheet 40. In the case where the back surface 4〇b is the above-described rough surface, for example, a case where another optical member is disposed between the seesaw 4〇 and the light guide plate 5A, the optical member and the seesaw 40 are prevented from adhering to each other. The thickness of the seesaw 40 may be the distance between the top 41& of the crotch portion 41 and the substantially flat back surface 40b of the crotch panel 4 (the opposite side of the surface 4?a). An example of the thickness of the mirror plate 40 is 〇 ! mm or more and 5 mm or less. The surface light source device 30 is an edge illumination type backlight unit that supplies backlight to the transmissive image display unit 2A. The surface light source device 3A includes a light guide plate 5A, and a light source portion 60, 60 disposed on the side of the light guide plate 50 opposite to the side surface 50a and the side surface 5b of the light guide plate 50, and 161699.doc • 10·201235718. The light source units 60 and 60 have a plurality of point light sources 61 arranged in a line shape (arranged in the γ direction in Fig. 1). An example of the point light source 61 is a light emitting diode. Therefore, the light source is incident on the light guide plate 50. The light source unit 6 can also be provided on the opposite side of the light guide plate 5?, and has a reflector as a reflection portion for reflecting light. Here, a plurality of the reflectors are illustrated. The light source unit 6 of the point light source 61 may be a linear light source such as a fluorescent lamp. The surface light source device 30 may include a reflection portion 70 located on the opposite side of the transmissive image display portion 20 with respect to the light guide plate 5A. The reflecting portion 7 is for causing the light emitted from the light guide plate 50 to the side of the reflecting portion 70 to enter the light guide plate 5 again. The reflecting portion 70 can be in the form of a sheet as shown in Fig. 1. The reflection portion 7A is a bottom surface of the frame body of the surface light source device 30 that houses the light guide plate %, and may be a bottom surface on which the mirror surface processing is performed. The light guide plate 50 will be described with reference to Figs. 1 and 2 . Fig. 2 is a plan view showing the light guide plate 50 shown in Fig. 1 from the back side. The shape of the light guide plate 5's plan view may be substantially rectangular. The light guide plate 50 includes a plate-shaped body portion 51 and a plurality of lenses 52 formed on the body portion 51. The body portion 51 includes a light transmissive material (or a transparent material). • An example of the refractive index of the optical material is 146 to i. The light transmissive material is a translucent resin material or a translucent glass material. The light-transmitting resin material is i: polycarbon 曰 曰 曰 曰 ( (refractive index: i 59), (10) resin (methacrylic acid y 酉曰 - the present ethylene copolymer resin) (refractive index: Μ), polystyrene tree 曰 (refractive index. i.59), AS resin (acrylonitrile-styrene copolymer tree 161699.doc -11 - 201235718 grease) (refractive index: 1.56~1.59), acrylic acid It is an ultraviolet curing resin (refractive index: 1.46 to 1.58), polymethyl methacrylate (PMMA) (refractive index: 1.49), and the like. As the light-transmitting resin material, PMMA is more preferable from the viewpoint of transparency. As shown in Fig. 1, the main body portion 51 includes an emitting surface (first surface) 5 la and a back surface (second surface) 5 lb which face each other in the thickness direction. The exit surface 51a and the back surface 51b are substantially flat. The main body portion 51 includes four side faces 51c, 51d, 51e, and 51f that intersect the exit surface 51a and the back surface 51b. In Fig. 1, two side faces 5 1 c and 5 1 d which face each other in the X direction are shown. The side surface 5 1 c and the side surface 51 d are also the side surface 50a and the side surface 50b facing the light source unit 60. The remaining two side faces 5 1 e, 5 1 f (see FIG. 3 ) of the four side faces 5 1 c, 5 1 d, 5 1 e, and 5 1 f of the main body portion 51 are opposed to each other in the Y direction. In Fig. 1, as an example of the arrangement relationship between the side surface 5 ic and the side surface 51d and the emission surface 51 a and the back surface 51 b , the side surface 51 c and the side surface 51 d are substantially perpendicular to the emission surface 51 a and the back surface 51 b. In the present embodiment, the other side faces 51e and 51f of the main body portion 51 are also orthogonal to the exit surface 51a and the back surface 51b. As shown in Figs. 1 and 2, a plurality of lens portions 52 are formed on the back surface 511). The lens portion 52 is transparent for emitting light propagating inside the light guide plate 5 from the exit surface 5 la side. Each of the lens portions 52 has a dome shape. The shape of each lens portion 52 will be described. For the sake of simplification of the description, the configuration in which the plurality of lens portions 52 have the same size will be described. The lens portion 52 has an outer shape: any point (one point) from the exit surface 5u? In the case of emitting light, the ratio (ratio) of the second light amount emitted from the exit position, that is, the point p, to the first light amount is more than 0.252%. The first! The amount of light is the amount per unit time of the total outgoing light emitted from point 161699.doc -12- 201235718 point P. The second amount of light is the amount per unit time of the outgoing light that is emitted from the point p to the specific area. The above specific region is a region where the angle of the point at the point p with respect to the normal to the exit surface 5 la is 25 . Above 3 5 . Hereinafter, the angular width around the normal line is ±5 in the X direction. . The shape of the lens portion 52 will be more specifically described with reference to Fig. 3 . FIG. 3 is a view for explaining the shape of the lens portion 52. Fig. 3(a) is a view showing a setting state of a local coordinate system on the exit surface 51a. Fig. 3(b) is a diagram for explaining a method of specifying the angle from the z-axis and the x-axis in the coordinate system shown in Fig. 3(a). Figure 3 is a diagram illustrating a specific area. As shown in Fig. 3(a), an arbitrary point p on the exit surface 5 i a is set as a partial xyz coordinate system of the origin, and a unit ball centered on the origin is assumed. The Z axis is orthogonal to the exit surface 51a in the xyz coordinate system. That is, the axis of the z-axis corresponds to the normal to the exit surface 51a. The X axis is approximately parallel to the χ direction. That is, the χ axis is substantially perpendicular to the side faces 51c and 51d which are the incident faces. In this case, the ^ axis is substantially coincident with the Y direction. The X axis, the y axis, and the 2 axis correspond to the χ direction, the γ direction, and the Ζ direction, and are the same in Figs. 3(b) and 3(c). As shown in Fig. 3(b), the angle (offset) formed between the direction of the outgoing light emitted from the point p and the two axes is set to θ, and the direction of the outgoing light and the angle of the x-axis are set ( The angle of the yaw is set in the setting, and the angle of the angle ρ with respect to the normal line of the exit surface 51a corresponds to the angle of the angle from the 2 axes, that is, the angular range of the corner, and the angular width around the normal corresponds to The angle range of the angle range that is satisfied by 0:: and then 'will be 0. Sleeping 90. And hehe. "The range of the light per unit time of the light emitted by the scope of the coffee (shown in Figure 3: the upper hemisphere of the ball) is the amount of the i-th light signal 16l699.doc -13· 201235718 for Qi 'will be as shown in Figure 3(c) The amount of light per unit time of the light emitted in a specific region (the hatched region of the surface of the ball shown in FIG. 3) of 25°$θ$35 and -5.$0$5〇 is the second light amount. In the Q factory, the ratio of the light amount Q2 to the light amount Q], that is, the light amount ratio is q (= q2 / qiX1 〇〇) (%). At this time, the shape of the lens portion 52 is satisfied.
〇-252(%)< Q 之形狀。 圖4係用以說明透鏡部52之外形形狀之例之圖式。圖4係 包含透鏡部52之中心轴線C之導光板5〇之剖面構成之模式 圖。 於透鏡部52中，將位於背面51b之相反侧之透鏡部52之 頂部稱作透鏡部52之前端部52a，將透鏡部52之背面51b侧 稱作透鏡部52之底部52b。於本實施形態中，假設透鏡部 52之形狀為將圖4所示之剖面形狀以中心軸線c為旋轉軸旋 轉所得之形狀。由此，透鏡部52之形狀於包含中心軸線^ 之任意剖面中左右對稱。透鏡部52具有如下外形形狀， 即，相接於透鏡部52之接面與背面51b所形成之角度自透 鏡部52之底部52b側至前端部52a側單調減小。 參照圖4，對透鏡部52之外形形狀之各種例子進行說 明。於圖4中，設定透鏡部52之寬度（直徑）gwaaim)、透鏡 部52之最大高度為1ι3(μπι)。 當⑴設定最大高度ha相對於寬度％之比即縱橫比為 ha/wa ’（II)於將透鏡部52之前端部52a之曲率半經設為 Γ(μπι)之情形時，設定曲率半徑r相對於寬度％之比為 161699.doc 14 201235718 r/wa，及（in)設定透鏡部52之底部5汕相對於背面51b之角 度（以下，稱為底部角度）為γ(。）時，光量比Q(%)滿足上述 範圍之透鏡部52之外形形狀可設為由ha/wa、r/wa及γ為圖5 所示之圖表内之組合之任一者而規定之形狀。 以下，與基於圖5之圖表所示之縱橫比[ha/wa]之情形區 分對應地對透鏡部52所滿足之形狀之條件具體地進行例 示0 (!)於 0.29$ ha/wa< 0.31之情形時 透鏡部52之形狀只要r/wa及γ滿足以下條件之任—者即 〇 (la) 〇< r/Wa$ 0.23且 31.57$γ$ 39.63 (lb) 0.44$1*/貿^0.48且51.66$丫$54.72 (lc) 0.52 $ r/waS 0.56且 58.03 $ 61.59 (ld) 0.60 $ r/waS 0.79且 65.41 S 85.24 (2) 於 0.27$ha/wa< 0.29 之情形時 透鏡部52之形狀之只要r/wa及γ滿足以下條件之任—者艮 *〇J* ο (2a) 0< r/waS 0.290且29.83 S 39.70 (2b) 0.5 13 S r/waS 0.848且 52.84 S 84·9〇 (3) 於 0.25Sha/wa< 0.27 之情形時 透鏡部52之形狀只要r/wa及γ滿足以下條件 '、卞 < 任一者即 -口〇 (3a) 0< r/wa^ 0.361 JL28.03 ^ 39.79 (3b) 0.601 $ r/waS 0.913且 54.24 $ 84.5 i 161699.doc •15· 201235718 (4) 於 0.23$ ha/wa< 0.25之情形時 透鏡部52之形狀只要r/wa及γ滿足以下條杜 π I卞疋任一者即 可。 (4a) 〇< r/waS 0.443且 26.17 39.89 (4b) 0.75 5 $ r/waS 0.990且 60.24S 84·〇5 (5) 於 0.21 $ ha/wa< 0.23之情形時 透鏡部52之形狀只要r/wa及γ滿足以下條件之任— 即 "5J" 〇 (5a) 〇< r/waS 0.597且 24.25 S 42.85 (5b) 0.881 $ r/waS 1.080且 62.98 S γ盔 83.52 (6) 於0.19S ha/wa< 0.21之情形時 透鏡部52之形狀只要r/wa及γ滿足以下條件之任一者即 〇 (6»)0<!：/^$〇.719且22.27$丫$43.32 (6b) 0.969S r/waS 1.031 且 60.71 S 66.44 (6c) 1.094$ r/waS 1.188且 72.70S 82.87 (7) 於0.17$1^&3<0.19之情形時 透鏡部52之形狀只要r/wa及γ滿足以下條件之任一者即 可。 (7a) 〇< r/Wa$ 0.868且 20.23 S 43.90 (7b) 1.215 S r/waS 1.285且 70.93 S 78.28 (8) 於0.15$113/你3<0.17之情形時 透鏡部52之形狀只要滿足〇.586蕊!>/诃$1133且 27.14$γ$ 49.42 即可。 161699.doc -16 - 201235718 (9) 於〇.13$11&/'^<〇.15之情形時 透鏡部52之形狀只要滿足0.938S r/wa$ 1.473且 30.57$ 58.14即可。 (10) 於 0.11$ha/wa<〇.l3 之情形時 透鏡部52之形狀只要滿足1.302Sr/wag 1.719且 32.70S 54.09即可。 (11) 於 0.09$ha/wa<〇.ii 之情形時 透鏡部52之形狀只要滿足i.8i3$r/Wa$2 〇63且 36.17$ 49.07即可。 前端部52a之曲率半徑Wa表示作為透鏡部52之頂部之前 端部52a之彎曲情況。例如，前端部52&之曲率半徑如圖4 所不’為假定有相接於前端部52a之圓（圖4中之虛線所示 之圓）之情形時之圓之半徑。底部角度係指通過中心轴線c 之剖面上之透鏡部52之輪廓線與背面5113之交點之位置處 的透鏡部52之接面p與背面51b之間所形成之角度。該底部 角度γ對應於將透鏡部52視為液滴之情形時之接觸角。相 對於前端部52a底部亦為透鏡部52之下端部。由此，底部 角度亦為下端部角度。 寬度wa為5 μιη以上i mm以下，較佳為1〇 μιη以上5〇〇 μιη 以下。此種尺寸之透鏡部52即所謂之微透鏡。 圖4表示出包含透鏡部52之中心軸線c之剖面之構成，故 而寬度wa對應於透鏡部52之最大寬度。匕為透鏡部52之前 端邛52a之位置處之厚度。從而，上述縱橫比[、㈤對應 於月j端部52a之位置處之透鏡部52之厚度（或高度）相對於透 16I699.doc 201235718 鏡部52之最大寬度，即，[前端部位置處之厚度]/[透鏡部 之最大寬]。通常’前端部52a之位置處之透鏡部52之厚度 最大，因而前端部52a之位置處之透鏡部52之厚度亦為透 鏡部52之最大厚度。上述（11)所記載之比對應於曲率半徑r 與透鏡部52之最大寬度之比’即，[曲率半徑]/[透鏡部之 最大寬]» 透鏡部52之材料可設定為與本體部51相同之材料。透鏡 部52之材料只要為透明材料，亦可與本體部5丨之材料不 同。 上述構成之導光板50之本體部51既可為由單獨之透光性 材料構成之單層之板狀體，亦可為積層有由彼此不同之透 光性材料構成之層之多層構造之板狀體。當透鏡部52之材 料與本體部51相同之情形時，導光板5〇為由單獨之透光性 材料構成之板狀體。 立進而，當使用透光性樹脂材料作為構成本體部51及透鏡 部52之透光性材料之情形時，亦可於該透光性樹脂材料中 添加紫外線吸收劑、帶電防止劑、抗氧化劑、加工穩定 劑、阻燃劑、潤滑劑等添加劑。該等添加劑可分別單獨 地、或組合2種以上而使用。於導光板別上添加有紫外線 吸收劑之形態中’當自光源部60輸出之光中含有大量紫外 線之情形等時’為了可防止由於紫外線而造成之導光板^ 之劣化，較佳為於導光板5〇上添加紫外線吸收劑。 作為紫外線吸㈣，例如可列舉：苯并三Μ紫外線吸 收劑 '二苯甲綱系紫外線吸收劑、氛基丙婦酸醋系紫外線 161699.doc 201235718 吸收劑、丙二酸酯系紫外線吸收劑、草醯苯胺系紫外線吸 收劑、三畊系紫外線吸收劑等。紫外線吸收劑之較佳例為 苯并三唑系紫外線吸收劑、三p井系紫外線吸收劑。 透光性樹脂材料通常不添加光擴散劑作為添加劑而使 用’但只要於不脫離本發明主旨之範圍内，即，只要為不 損害本發明之目的之少量，則亦可於透光性樹脂材料中添 加光擴散劑。 作為光擴散劑，通常使用與主要構成導光板50,具體而 言，本體部51及透鏡部52之如上所述之透明材料之折射率 不同之粉末，使其分散於透明材料中而使用。作為該光擴 政劑’例如可使用苯乙稀樹脂粒子、曱基丙稀樹脂粒子等 有機粒子、碳酸钟粒子、二氧化石夕粒子等無機粒子，其粒 子徑通常為〇. 8 μπι〜5 0 μπι。 出射面5 1 a較佳為平坦。然而，為了細紋之減少出射面 5 la亦可略微具有表層擴散功能。 具備上述透鏡部52之導光板50可藉由喷墨印刷（嘴墨 法）、感光聚合法、擠壓成型或射出成型等而製造。 於使用喷墨印刷（喷墨法）或感光聚合法製造導光板50 時，作為透鏡部52之材料，可利用紫外線硬化樹脂。於該〇-252 (%) < Q shape. FIG. 4 is a view for explaining an example of the outer shape of the lens portion 52. Fig. 4 is a schematic view showing a cross-sectional configuration of a light guide plate 5A including a central axis C of the lens portion 52. In the lens portion 52, the top of the lens portion 52 on the opposite side of the back surface 51b is referred to as the front end portion 52a of the lens portion 52, and the side of the back surface 51b of the lens portion 52 is referred to as the bottom portion 52b of the lens portion 52. In the present embodiment, the shape of the lens portion 52 is a shape obtained by rotating the cross-sectional shape shown in Fig. 4 with the central axis c as a rotation axis. Thereby, the shape of the lens portion 52 is bilaterally symmetrical in any cross section including the central axis ^. The lens portion 52 has an outer shape in which the angle formed by the contact surface of the lens portion 52 and the back surface 51b monotonously decreases from the bottom portion 52b side to the front end portion 52a side of the lens portion 52. Various examples of the outer shape of the lens portion 52 will be described with reference to Fig. 4 . In Fig. 4, the width (diameter) gwaaim of the lens portion 52 is set, and the maximum height of the lens portion 52 is 1 ι 3 (μπι). When (1) sets the ratio of the maximum height ha to the width %, that is, the aspect ratio is ha/wa '(II), when the curvature of the front end portion 52a of the lens portion 52 is half set to Γ (μπι), the radius of curvature r is set. The ratio with respect to the width % is 161699.doc 14 201235718 r/wa, and (in) the amount of light when the angle of the bottom 5 透镜 of the lens portion 52 with respect to the back surface 51 b (hereinafter referred to as the bottom angle) is γ (.) The outer shape of the lens portion 52 whose ratio Q (%) satisfies the above range may be a shape defined by any combination of ha/wa, r/wa, and γ in the graph shown in FIG. 5. Hereinafter, the condition of the shape satisfied by the lens portion 52 correspondingly to the case of the aspect ratio [ha/wa] shown in the graph of FIG. 5 is specifically exemplified by 0 (!) at 0.29 $ ha/wa < 0.31 In the case, the shape of the lens portion 52 is such that r/wa and γ satisfy any of the following conditions: 〇(la) 〇<r/Wa$ 0.23 and 31.57$γ$ 39.63 (lb) 0.44$1*/trade^0.48 and 51.66$丫$54.72 (lc) 0.52 $ r/waS 0.56 and 58.03 $ 61.59 (ld) 0.60 $ r/waS 0.79 and 65.41 S 85.24 (2) In the case of 0.27$ha/wa< 0.29, the shape of the lens portion 52 As long as r/wa and γ satisfy any of the following conditions—艮*〇J* ο (2a) 0< r/waS 0.290 and 29.83 S 39.70 (2b) 0.5 13 S r/waS 0.848 and 52.84 S 84·9〇 ( 3) In the case of 0.25 Sha/wa < 0.27, the shape of the lens portion 52 is as long as r/wa and γ satisfy the following condition ', 卞 < either one - mouth 〇 (3a) 0< r/wa^ 0.361 JL28. 03 ^ 39.79 (3b) 0.601 $ r/waS 0.913 and 54.24 $ 84.5 i 161699.doc •15· 201235718 (4) In the case of 0.23$ ha/wa< 0.25, the shape of the lens portion 52 is satisfied as long as r/wa and γ are satisfied. Any of the following can be used. (4a) 〇< r/waS 0.443 and 26.17 39.89 (4b) 0.75 5 $ r/waS 0.990 and 60.24S 84·〇5 (5) In the case of 0.21 $ ha/wa< 0.23, the shape of the lens portion 52 is as long as r/wa and γ satisfy the following conditions—that is, "5J" 〇(5a) 〇< r/waS 0.597 and 24.25 S 42.85 (5b) 0.881 $ r/waS 1.080 and 62.98 S γ helmet 83.52 (6) 0.19S ha/wa<2> The shape of the lens portion 52 in the case of 0.21, as long as r/wa and γ satisfy any of the following conditions: 〇(6»)0<!:/^$〇.719 and 22.27$丫$43.32 ( 6b) 0.969S r/waS 1.031 and 60.71 S 66.44 (6c) 1.094$ r/waS 1.188 and 72.70S 82.87 (7) In the case of 0.17$1^&3<0.19, the shape of the lens portion 52 is only r/wa and γ can satisfy any of the following conditions. (7a) 〇< r/Wa$ 0.868 and 20.23 S 43.90 (7b) 1.215 S r/waS 1.285 and 70.93 S 78.28 (8) In the case of 0.15$113/you 3<0.17, the shape of the lens portion 52 is only satisfied. .586 蕊!>/诃$1133 and 27.14$γ$ 49.42. 161699.doc -16 - 201235718 (9) In the case of 〇.13$11&/'^<〇.15, the shape of the lens portion 52 is only required to satisfy 0.938S r/wa$ 1.473 and 30.57$58.14. (10) In the case of 0.11$ha/wa<〇.l3, the shape of the lens portion 52 may be as long as 1.302 Sr/wag 1.719 and 32.70 S 54.09 are satisfied. (11) In the case of 0.09$ha/wa<〇.ii, the shape of the lens portion 52 may be as long as i.8i3$r/Wa$2 〇63 and 36.17$49.07 are satisfied. The radius of curvature Wa of the front end portion 52a indicates the bending of the end portion 52a before the top of the lens portion 52. For example, the radius of curvature of the front end portion 52 & as shown in Fig. 4 is a radius of a circle assuming that a circle of the front end portion 52a (a circle indicated by a broken line in Fig. 4) is formed. The bottom angle refers to an angle formed between the joint surface p of the lens portion 52 and the back surface 51b at a position passing through the intersection of the contour line of the lens portion 52 on the cross section of the center axis c and the back surface 5113. This bottom angle γ corresponds to the contact angle when the lens portion 52 is regarded as a droplet. The bottom portion of the front end portion 52a is also the lower end portion of the lens portion 52. Thus, the bottom angle is also the lower end angle. The width wa is 5 μm or more and i mm or less, preferably 1 〇 μηη or more and 5 〇〇 μιη or less. The lens portion 52 of such a size is a so-called microlens. Fig. 4 shows a configuration including a cross section of the central axis c of the lens portion 52, and therefore the width wa corresponds to the maximum width of the lens portion 52.匕 is the thickness at the position of the front end 52a of the lens portion 52. Therefore, the aspect ratio [, (5) corresponds to the thickness (or height) of the lens portion 52 at the position of the end portion 52a of the month j relative to the maximum width of the mirror portion 52 of the 16I699.doc 201235718, that is, [at the position of the front end portion] Thickness] / [Maximum width of the lens portion]. Generally, the thickness of the lens portion 52 at the position of the front end portion 52a is the largest, and therefore the thickness of the lens portion 52 at the position of the front end portion 52a is also the maximum thickness of the lens portion 52. The ratio described in the above (11) corresponds to the ratio of the radius of curvature r to the maximum width of the lens portion 52, that is, the [curvature radius] / [the maximum width of the lens portion] » the material of the lens portion 52 can be set to be the body portion 51 The same material. The material of the lens portion 52 may be different from the material of the body portion 5 as long as it is a transparent material. The main body portion 51 of the light guide plate 50 having the above-described configuration may be a single-layer plate-like body made of a single light-transmitting material, or a multi-layered structure in which a layer composed of a light-transmitting material different from each other is laminated. Shape. When the material of the lens portion 52 is the same as that of the main body portion 51, the light guide plate 5' is a plate-like body composed of a single light-transmitting material. Further, when a light-transmitting resin material is used as the light-transmitting material constituting the main body portion 51 and the lens portion 52, an ultraviolet absorber, a charge inhibitor, an antioxidant, or the like may be added to the light-transmitting resin material. Processing stabilizers, flame retardants, lubricants and other additives. These additives may be used singly or in combination of two or more kinds. In the case where an ultraviolet absorber is added to the light guide plate, 'when the light output from the light source unit 60 contains a large amount of ultraviolet rays, etc.', in order to prevent deterioration of the light guide plate due to ultraviolet rays, it is preferable to guide An ultraviolet absorber is added to the light plate 5〇. Examples of the ultraviolet absorption (four) include a benzotriazole ultraviolet absorber, a diphenylmethyl group ultraviolet absorber, and an ultraviolet phenate 161699.doc 201235718 absorbent, a malonate ultraviolet absorber, Grasshopper aniline UV absorber, three tillage UV absorber, etc. Preferred examples of the ultraviolet absorber are a benzotriazole-based ultraviolet absorber and a triple-p-system ultraviolet absorber. The light-transmitting resin material is generally used without using a light-diffusing agent as an additive. However, as long as it does not deviate from the gist of the present invention, it may be a light-transmitting resin material as long as it is a small amount which does not impair the object of the present invention. Add a light diffusing agent. As the light diffusing agent, a powder which mainly constitutes the light guide plate 50, specifically, the refractive index of the transparent material as described above, of the main body portion 51 and the lens portion 52 is used, and is dispersed and used in a transparent material. As the light diffusing agent, for example, organic particles such as styrene resin particles or mercapto propylene resin particles, carbonic acid particles, and particles such as cerium oxide particles can be used, and the particle diameter is usually 〇. 8 μπι 5 0 μπι. The exit surface 51a is preferably flat. However, in order to reduce the fine lines, the exit surface 5 la may also have a surface diffusion function. The light guide plate 50 including the lens portion 52 can be manufactured by inkjet printing (mouth ink method), photopolymerization method, extrusion molding, injection molding, or the like. When the light guide plate 50 is manufactured by inkjet printing (inkjet method) or photopolymerization method, as the material of the lens portion 52, an ultraviolet curable resin can be used. In this
It形時，作為紫外線硬化樹脂，可使用丙烯酸系紫外線硬 化樹脂。 對以丙烯酸系紫外線硬化樹脂作為透鏡部52之材料且利 用噴墨印刷之情形時之導光板50之製造方法之一例進行說 明。於該情形時，作為板狀體之本體部51係藉由擠壓成型 161699.doc 201235718 或射出成型等而形成。其次，於應成為本體部51之背面 51b之面，一面操作喷墨頭，一面滴下（印刷）紫外線硬化樹 脂。繼而，對紫外線硬化樹脂照射紫外線，使紫外線硬化 樹脂硬化’由此所滴下之紫外線硬化樹脂成為透鏡部52。 由紫外線硬化樹脂形成透鏡部52之情形時之紫外線硬化 樹脂之例’例如為丙烯酸系紫外線硬化樹脂。 此處’例示了利用噴墨印刷之製造方法，但如上所述， 亦可藉由擠壓成型或射出成形等製造直接形成透鏡部52之 導光板50。於該情形時，透鏡部52之材料與本體部51之材 料相同。 其次’以如圖1所示採用導光板50作為面光源裝置30之 一部分’且將導光板50應用於透過型圖像顯示裝置1〇中之 情形為例，對上述導光板50之作用效果進行說明。圖6係 圖1所示之透過型圖像顯示裝置10之一部分放大圖。在圖6 中’於圖1中將側面50a(側面5 lc)側放大表示。 若光源部60所具有之點狀光源61發光，則來自點狀光源 61之光自與點狀光源61對向之導光板50之側面50a入射至 導光板50。入射至導光板5 0之光一面於導光板50内全反射 一面於導光板50内傳播。若於導光板50内傳播之光入射至 透鏡部52，則於透鏡部52内光於全反射條件以外之條件下 反射。故而，反射光自出射面51a出射。 透鏡部52具有光量比Q大於0·252°/〇之形狀，故而自出射 面51a出射之光之出射角Θ。約為30°左右，更具體而言，易 於成為25°以上35。以下之範圍。其結果，經過稜鏡板40而 161699.doc •20· 201235718 出射至透過型圖像顯示部20之光之亮度提高。 以白點81代替透鏡部52形成於背面51b之導光板80之情 形為例，對該點進行說明。圖7係表示複數個白點81形成 於背面51b之導光板80之構成之一例之模式圖》於圖7中， 為了進行說明，亦一併表示出點狀光源61及稜鏡板40。導 光板80之構成除於背面51b形成有白點81代替透鏡部52之 點以外’其他與導光板50之構成相同。於導光板80之要素 中’對與導光板50相同之要素標註相同之符號。 於導光板80之情形時，自點狀光源61輸出且入射至導光 板80内之光亦一面於導光板内全反射一面於導光板内 傳播。當於導光板80内傳播之光於白點81之位置處反射之 情形時，於全反射條件以外亦產生反射之光。故而，藉由 白點81反射之光自出射面51a出射。此時，如圖8所示，有 出射角Θ。變成約60。左右之傾向。圖8係表示相對於出射角 之出射光之強度分佈之測定結果之曲線圖。圖8之橫軸 為來自出射面51a之出射光之出射角θ。，縱軸為光度（cd)。 自導光板80出射之光以與出射角0〇大致相同之角度入射至 稜鏡板40。從而，以約6〇〇之出射角0。出射之出射光以約 60°之入射角入射至稜鏡板4〇。 然而，入射角60。左右而入射至稜鏡板4〇之光於自稜 鏡部41出射時，易於如圖7所示沿自z方向偏離之方向出 射。其結果，有入射至透過型圖像顯示部2〇之光減少之傾 向。 另一方面，於導光板50中，光易於以3〇0±5〇(即，25〇以 161699.doc 201235718 上35。以下）之範圍内之出射角θ〇出射。於該情形時，光以 3〇 ±5。之入射角θί入射至稜鏡板4〇。於向稜鏡板4〇之光之 入射角θι為30。左右之情形時，自稜鏡部41出射之光如圖6 所不，易於沿板厚方向（z方向）出射。換而言之，自導光 板50出射之光沿板厚方向即正面方向更多地聚光。 再者’亦存在構成稜鏡部41之一對側面42a、42b中，自 面42a出射之光沿板厚方向出射，而自另一面42b出射之 光自板厚方向偏離之情形。然而，由於易於自一側面42a 沿板厚方向出射，故而較入射角h為約6〇。之情形時，朝向 透過型圖像顯示部2〇出射之光量變多。因此，正面方向之 亮度提高’作為結果’可藉由透過型圖像顯示部2〇顯示更 加明亮之圖像。 其次’根據模擬結果，對於透鏡部52滿足圖5所示之條 件之情形時，出射角θ。為3〇。左右之出射光變得更多之點 進行說明。 圖9係表示模擬模型之模式圖。為了便於說明，對與圖工 所示之構成要素對應之構成要素如以導光板5〇m之形式標 廑有Μ而記載。模擬係於如圖9所示於導光板5〇m之側面 5〇Ma、50Mb之側方分別配置有點狀光源61m、61m，且於導 光板50M之下方配置有作為反射部7〇m之反射片之模型中， 使用光線追蹤法而進行。點狀光源61m、61m配置於側面 5〇Ma及側面5〇Mb之側方。點狀光源61^、61m於導光板5~ 之短邊方向上，位於短邊方向之中央部》 模擬條件如下所述。 161699.doc 22· 201235718 .導光板50m之構成材料：假定本體部51m及透鏡部52m 均為PMMA(折射率：1.49) 導光板50M之俯視形狀（自板厚方向觀察之形狀長方 形 •導光板50M之長邊之長度wi : 500 mm •導光板50M之短邊之長度W2:20mm •本體部51m之厚度t: 4 mm .導光板50m之透鏡部52Mi前端部52Ma與反射部70m2 間之距離：0.1 mm .反射部70M :假定反射鏡（反射率ι〇〇〇/〇) •點狀光源61 μ之特性：作為點光源，假定等向出射 .自點狀光源61 μ出射之光之波長：假定5 5 0 nm •點狀光源6丨!^與導光板5〇M之距離：0.1 mm 再者’於本體部51 μ之侧面5 1 Me及側面5 1 Mf假定週期性 邊界條件。即，假設於侧面5lMe及側面5lMf光全部反射並 返回至導光板50内。 模擬中’於如圖4所示包含透鏡部52M之中心軸線c之透 鏡部52M之剖面構成中，以圓錐曲線表示透鏡部52m之輪廓 線。具體而言’如圖1〇所示，設定uv(ultraviolet，紫外線） 座標系’透鏡部52m之剖面形狀藉由式（1)所示之圓錐曲線 v(u)而規定。uv座標系之v軸對應於圖4中之透鏡部52]^之 中心軸線C。u軸對應於圖4所示之X方向。 161699.doc -23- 201235718 [數1]In the case of the It shape, an acrylic ultraviolet curable resin can be used as the ultraviolet curable resin. An example of a method of manufacturing the light guide plate 50 in the case where an acrylic ultraviolet curable resin is used as the material of the lens portion 52 and inkjet printing is used will be described. In this case, the body portion 51 as a plate-like body is formed by extrusion molding 161699.doc 201235718 or injection molding. Next, the ultraviolet curable resin is dropped (printed) while operating the ink jet head on the surface of the back surface 51b of the main body portion 51. Then, the ultraviolet curable resin is irradiated with ultraviolet rays to cure the ultraviolet curable resin. The ultraviolet curable resin thus dropped becomes the lens portion 52. An example of the ultraviolet curable resin in the case where the lens portion 52 is formed of the ultraviolet curable resin is, for example, an acrylic ultraviolet curable resin. Here, the manufacturing method by inkjet printing is exemplified, but as described above, the light guide plate 50 directly forming the lens portion 52 may be manufactured by extrusion molding or injection molding. In this case, the material of the lens portion 52 is the same as that of the body portion 51. Next, the case where the light guide plate 50 is used as a part of the surface light source device 30 as shown in FIG. 1 and the light guide plate 50 is applied to the transmissive image display device 1 is taken as an example, and the effect of the light guide plate 50 is performed. Description. Fig. 6 is a partially enlarged view of a transmissive image display device 10 shown in Fig. 1. In Fig. 6, the side 50a (side surface 5 lc) side is shown enlarged in Fig. 1 . When the point light source 61 of the light source unit 60 emits light, the light from the point light source 61 enters the light guide plate 50 from the side surface 50a of the light guide plate 50 opposed to the point light source 61. The light incident on the light guide plate 50 is totally reflected on the light guide plate 50 and propagates in the light guide plate 50. When the light propagating in the light guide plate 50 is incident on the lens portion 52, the light is reflected in the lens portion 52 under conditions other than the total reflection condition. Therefore, the reflected light is emitted from the exit surface 51a. The lens portion 52 has a shape in which the light amount ratio Q is larger than 0·252°/〇, and thus the exit angle Θ of the light emitted from the exit surface 51a. It is about 30°, and more specifically, it is easy to become 25° or more 35. The following range. As a result, the brightness of the light emitted to the transmissive image display unit 20 is increased by the seesaw 40 and 161699.doc • 20·201235718. This point will be described by taking a white point 81 instead of the case where the lens portion 52 is formed on the light guide plate 80 of the back surface 51b. Fig. 7 is a schematic view showing an example of a configuration in which a plurality of white dots 81 are formed on the light guide plate 80 on the back surface 51b. In Fig. 7, the point light source 61 and the seesaw 40 are also shown together. The light guide plate 80 is configured in the same manner as the light guide plate 50 except that the back surface 51b is formed with a white dot 81 instead of the lens portion 52. In the elements of the light guide plate 80, the same elements as those of the light guide plate 50 are denoted by the same reference numerals. In the case of the light guide plate 80, the light output from the point light source 61 and incident on the light guide plate 80 also propagates in the light guide plate while being totally reflected in the light guide plate. When the light propagating in the light guide plate 80 is reflected at the position of the white point 81, the reflected light is generated in addition to the total reflection condition. Therefore, the light reflected by the white point 81 is emitted from the exit surface 51a. At this time, as shown in Fig. 8, there is an exit angle Θ. It becomes approximately 60. The tendency to influence. Fig. 8 is a graph showing the measurement results of the intensity distribution of the outgoing light with respect to the exit angle. The horizontal axis of Fig. 8 is the exit angle θ of the outgoing light from the exit surface 51a. The vertical axis is luminosity (cd). The light emitted from the light guide plate 80 is incident on the raft 40 at an angle substantially the same as the exit angle 0 。. Thus, the exit angle of 0 is about 6 。. The exiting light exiting is incident on the raft 4 at an incident angle of about 60°. However, the angle of incidence is 60. When the light incident on the side plate 4 of the right and left sides is emitted from the prism portion 41, it is easy to be emitted in the direction deviated from the z direction as shown in Fig. 7 . As a result, there is a tendency for the light incident on the transmissive image display unit 2 to decrease. On the other hand, in the light guide plate 50, light is easily emitted at an exit angle θ 范围 within a range of 3 〇 0 ± 5 〇 (i.e., 25 〇 to 161699.doc 201235718 above 35 Å). In this case, the light is 3 〇 ±5. The incident angle θί is incident on the seesaw 4〇. The incident angle θι of the light to the 稜鏡4 is 30. In the case of the left and right, the light emitted from the dam portion 41 is not as shown in Fig. 6, and is easily emitted in the thickness direction (z direction). In other words, the light emitted from the light guide plate 50 is more concentrated in the thickness direction, that is, the front direction. Further, in one of the side faces 42a and 42b constituting the crotch portion 41, the light emitted from the surface 42a is emitted in the thickness direction, and the light emitted from the other surface 42b is deviated from the thickness direction. However, since it is easy to exit from the one side surface 42a in the thickness direction, the incident angle h is about 6 较. In this case, the amount of light emitted toward the transmissive image display unit 2 is increased. Therefore, the luminance in the front direction is increased as a result, and a brighter image can be displayed by the transmissive image display unit 2〇. Next, according to the simulation result, when the lens portion 52 satisfies the condition shown in Fig. 5, the angle θ is emitted. It is 3 〇. The point where the left and right outgoing lights become more is explained. Fig. 9 is a schematic view showing a simulation model. For the sake of convenience of explanation, the constituent elements corresponding to the constituent elements shown in the drawing are described in the form of the light guide plate 5〇m. In the simulation, the spot light sources 61m and 61m are disposed on the side surfaces 5〇Ma and 50Mb of the light guide plate 5〇m as shown in FIG. 9, and the reflection as the reflection portion 7〇m is disposed below the light guide plate 50M. In the model of the film, the ray tracing method is used. The point light sources 61m and 61m are disposed on the side of the side surface 5〇Ma and the side surface 5〇Mb. The point light sources 61^ and 61m are located at the center of the short side direction in the short side direction of the light guide plate 5~. The simulation conditions are as follows. 161699.doc 22·201235718. constituting material of the light guide plate 50m: It is assumed that the main body portion 51m and the lens portion 52m are both PMMA (refractive index: 1.49). The shape of the light guide plate 50M (the rectangular shape viewed from the plate thickness direction; the light guide plate 50M) The length of the long side wi: 500 mm • the length of the short side of the light guide plate 50M W2: 20 mm • the thickness t of the main body portion 51m: 4 mm. The distance between the front end portion 52Ma of the lens portion 52Mi of the light guide plate 50m and the reflection portion 70m2: 0.1 mm. Reflecting part 70M: Assume mirror (reflectance ι〇〇〇/〇) • Characteristics of point light source 61 μ: As a point source, assume an isotropic emission. The wavelength of light emitted from the point source 61 μ: Assume that the 5 5 0 nm • point light source 6丨!^ is spaced from the light guide plate 5〇M: 0.1 mm. Further, 'the side boundary of the body 51 μ1 5 1 Me and the side surface 5 1 Mf assume periodic boundary conditions. It is assumed that all of the side surface 5lMe and the side surface 51Mf are reflected and returned to the light guide plate 50. In the simulation, in the cross-sectional configuration of the lens portion 52M including the central axis c of the lens portion 52M as shown in Fig. 4, the lens portion is represented by a conic curve. 52m outline. Specifically, as shown in Figure 1,, set uv (ult Raviolet, ultraviolet light) The cross-sectional shape of the coordinate portion 'the lens portion 52m is defined by the conic curve v(u) shown in the formula (1). The v-axis of the uv coordinate system corresponds to the center of the lens portion 52 in FIG. The axis C. The u axis corresponds to the X direction shown in Fig. 4. 161699.doc -23- 201235718 [Number 1]
卷動式2)中’、係表示式⑴所示之圓錐曲線之尖頂部之 :為。:=出透鏡部心前端部心之尖頂部。例如當 读㈣ 鏡〇P 52m之外形成為拋物線形狀，當kaA 1時， 之外形成為稜鏡形狀，當、為“時，透鏡部％ 之外形成為將橢圓切除一半所形成之形狀。 模擬模型中，於本體部51m之背面51以以固定間隔配置 有複數個透鏡部52m。具體而言’排列複數個正方形而形 成之正方格子相對於背面51以而設定，於作為正方格子之 構成單位之各正方形令配置有一個透鏡部％。透鏡部％ 相對於正方格子之構成單位之佔有率（透鏡部％相對於構 成單位之覆蓋率）設定為78.5。/£^作為正方格子之構成單位 之正方形之一邊之長度設定為500 μηι。 於模擬中，首先，設計具有藉由式（1)規定之外形之透 鏡部52Μ。假想對具有所設計之透鏡部52μ之導光板5〇μ， 自點狀光源61μ入射光之情形’於導光板5〇Μ2出射面HMa 之中央部假定作為光之出射位置之點p，計算光自點p出射 之情形時之出射光之輻射亮度。 然後’設定圖3(b)及（c)所示之局部之xyz座標系，算出 光量Q,及光量Q2。於模擬中’為了與下述之用於比較之實 161699.doc -24- 201235718 驗結果進行對比，於半球面上之複數個點算出於 02K90。及0%b 360。之範圍（相當於圖叫所示之單 位球之球面中zg〇之區域之半球面）内出射之出射光之輻 射亮度。其後’根據所算出之輻射亮度，#出半球面整體 之總輻射束及特定區域之輻射束。 算出轄射亮度之上述複數個點以包含特定區域内之點之 方式，沿Θ方向每5。的幅度設定一個’且沿多方向每ι〇。的 幅度設定-冑。根據輕#亮度算出總輕射束及輕射束係以 如下方式實施。 即，將各計算點之輻射亮度換算成每單位立體角之輻射 束。作為單位立體角設定為1/4;^其次，將各輻射束換算 成單位球面上之每個面要素之輻射束。其後，遍及半球面 整體地對單位球面上之每個面要素之輻射束進行數值積分 從而算出總輻射束。於25。$0$35。且_5。^卢。之範圍内 對單位球面上之每個面要素之輻射束進行數值積分從而算 出輻射束。於模擬中，算出為物理量之輻射束，輻射束對 應於所謂之心理物理量之光通量（每單位時間之光量）。由 此，特定區域之輻射束相對於所算出之總輻射束之比對應 於特定區域之光通量（每單位時間之光量）相對於總光通量 (每單位時間之總光量）之比。從而，將[特定區域之輻射 束]/ [總轄射束]設定為光量比Q。 藉由變更ka&ha/Wa，對所設定之複數個透鏡部52m之形 狀實施上述模擬，算出光量比Q。 為了進行比較，使用具有白點81之導光板8〇獲得基於實 161699.doc -25· 201235718 測值之光量比Q。於用以比較之實驗（以下，稱作「比較實 驗」）中，取出三星電子股份有限公司製造 「UN46B8000」中所使用之背光單元，將該背光單元之導 光板作為導光板80而使用。然後，使用導光板8〇與背光單 元之光源，並於導光板80之背面側設置銀蒸鍍反射膜，藉 此實現與圖9之構成相同之構成。比較實驗中所使用之導 光板80具有白點81。而且’於比較實驗中，與圖9所示之 模擬模型之情形同樣地，將白色光自導光板8〇之側面供給 至導光板80内，測定來自出射面51a之所定位置（導光板8〇 之中央位置）之亮度。測定係使用亮度計（T〇pc〇M公司製 造「色彩亮度計BM-5 AS」）而進行。具體而言，在相當於 圖3(b)所示之球面中之區域之半球面内之複數個測定 點處分別測定亮度。複數個測定點係以與模擬之輻射亮度 之算出點對應之方式設定。 根據所測定之亮度，與模擬之情形時同樣地算出總光通 量及特定區域之光通量。即，將各測定點之亮度換算成每 單位立體角之光通量。作為單位立體角設定為1/4π。其 -人’將各光通量換算成單位球面上之每個面要素之光通 量。其後’遍及半球面整體地對單位球面上之每個面要素 之光通量進行數值積分從而算出總光通量。於 25°$θ各35。且-5。^ 0^5。之範圍内對單位球面上之每個面 要素之光通量進行數值積分從而算出特定區域之光通量。 光通量對應於每單位時間之光量，故而總光通量對應於光 量Qi’特定區域之光通量對應於光量仏。由此，將光量^ 161699.doc •26- 201235718 除以光量Q! ’由此光算出量比Q。設置有白點81之情形時 之光量比Q為0.252%。 模擬結果如圖11及圖12所示之圖表。圖11及圖12係表示 由式（1)之1^及縱橫比[ha/wa]規定之透鏡形狀與光量比Q之 關係之圖表。圖11表示ka為〇以上至0.9之範圍，圖12表示 ka為-0.9以上且-〇·1以下之範圍。 於圖11及圖12中，表示光量比Q較大者於出射角30。附近 出射之光較多。即，於光量比q較大者與棱鏡板4〇μ組合 時，可謀求亮度提高。 圖13及圖14係表示由圖u及圖12所示之1^與縱橫比 [ha/wa]規定之透鏡形狀之前端部52Ma之曲率半徑r相對於 寬度wa之比[r/Wa]的圖表。又’圖15及圖16係表示由圖u 及圖12所示之ka與縱橫比[ha/Wa]規定之透鏡形狀之底部角 度之圖表。 於圖11及圖12所示之圖表中，對大於針對白點81算出之 光量比Q之值（0.252%)之光量比Q標註下劃線，於與圖丨丨對 應之圖13及圖15、以及與圖12對應之圖14及圖16中，對實 現圖11及圖12中標註有下劃線之光量比Q之透鏡部52的前 端部52a之曲率半徑相對於寬度％之[r/Wa]及底部角度γ標 註有下劃線。 因此’於圖11〜圖16中，於由標註有下劃線處之ha/Wa、 曲率半徑相對於寬度Wa2[r/Wa]及底部角度γ規定之透鏡部 52中，可實現較具有白點81之導光板8〇之情形時大之光量 比Q。 161699.doc •27- 201235718 而且，圖11〜圖16中標註有下劃線處之規定透鏡部52m 之形狀的縱橫比[ha/wa]、曲率半徑相對於寬度％之[r/Wa] 及底部角度γ為圖5所示之圖表所示之範圍内。 從而，於圖5所示之具備藉由ha/Wa、r/w及γ所示之組合 而規定之透鏡部52的導光板50中，出射角0。易於成為25。 以上35。以下。故而，如上所述，藉由採用本實施形態中 之導光板50，於具備棱鏡板4〇之透過型圖像顯示裝置1〇 中，可以更高之亮度照明透過型圖像顯示部2〇。其結果， 可謀求藉由透過型圖像顯示部2〇顯示之圖像之亮度提高。 以上，對本發明之實施形態進行了說明，但本發明並不 限疋於上述貫施形態，而可於不脫離發明主旨之範圍内進 行各種變更。 上述實施形態係假設形成於背面5 1 b上之複數個透鏡部 52具有光量比Q大於〇.252%之形狀而進行說明。然而，只 要在形成於背面51b上之複數個透鏡部中，至少一半以上 之透鏡部為上述實施形態中所說明之透鏡部5 2即可。換而 言之，形成於背面51b之複數個透鏡部亦可包含其一半為 作為上述透鏡部52之第1透鏡部、剩餘一半為不滿足上述 實施形態中所說明之條件之第2透鏡部。作為透鏡部52之 第1透鏡部之數量與上述第2透鏡部之數量之比亦可為6: 4 〇 透鏡部5 2之形狀較佳為如圖4所例示，具有如下形狀， 即，透鏡部52之接面與背面51|5所形成之角度自透鏡部52 之底部側至前端部側單調減小。然而，透鏡部5 2具有藉由 161699.doc -28- 201235718 圖5所不之ha/Wa、r/w&y所示之組合而規定之形狀等，由 此只要具有光量比Q大於0,252%之形狀，則即便透鏡部52 之接面與月面5 1 b所形成之角度並非至前端部52a側地單調 減小亦可。 進而，光源部60之數量並不限定於2個。例如，光源部 亦了為3個以上。於該情形時，例如，可對本體部$ 1所 具有之側面51e、5 If中之至少一個側面進而設置光源部 60。光源部60亦可對導光板設置一個❶於該情形時，光源 部60配置於圖i所示之側面51c及側面5id中之一者。 於圖1所示之透過型圖像顯示裝置1〇中，只要不損害本 發月之目的，則既可於導光板5 〇與稜鏡板之間配置另— 光學構件，亦可於稜鏡板4〇與透過型圖像顯示部1〇之間配 置另一光學構件。於導光板5〇與稜鏡板40之間設置之另一 光學構件之例為具有不損害本發明之目的之程度之光擴散 特性之光擴散薄片或微透鏡薄片。於稜鏡板4〇與透過型圖 像顯示部1〇之間設置之另一光學構件之例為反射型偏光分 離薄片、光擴散薄片或微透鏡薄片。 【圖式簡單說明】 圖1係表不應用本發明之導光板之一實施形態之透過型 圖像顯示裝置之概略構成之模式圖。 圖2係自$面側觀察圖丨所示之導光板之情形時之平面 圖。 圖3係用以說明透鏡部之形狀之圖式’圖3(幻係表示出射 面上之局#之座標系之設定狀態之圖式，圖3(b)係用以說 161699.doc -29· 201235718 明自圖3⑷所示之座標系中之z轴及χ軸算起之角度之規定 方法的圖式，圖3⑷係用以說明料區域之圖式。 圖4係用以說明透鏡部之外形形狀之例之圖式。 圖5係表示規定透鏡部之外形形狀之條件之圖表。 圖6係圖1所示之透過型圖像顯示裝置之-部分放大圖。 圖7係表示㈣個白點形成於背面之導光板之構成之一 例之模式圖。 圖8係表示㈣於出射W之出射光之強度分佈之測定 結果之曲線圖。 圖9係表示模擬模型之模式圖。 圖係表示模擬中所使用之透鏡部之外形形狀之圖式。 圖11係表不模擬中所使用之透鏡形狀與光量比之關係之 圖表。 圖12係表示模擬中所使用之透鏡形狀與光量比之關係之 圖表β 圖13係表示由圖u所示之、與縱橫比所規定之透 鏡形狀之前端部之曲率半徑Γ相對於寬度％之圖表。 圖14係表示由圖12所示之]^與縱橫比[ha/Wa]規定之透鏡 形狀之刖端部之曲率半徑Γ相對於寬度％之圖表。In the scrolling type 2), the line indicates the tip of the conic curve shown in the formula (1): . := The tip of the front end of the lens is out. For example, when reading (4) mirror 〇 P 52m, it is formed into a parabolic shape, and when kaA 1 is formed, it is formed into a 稜鏡 shape, and when it is “, the lens portion is formed to be formed by cutting the ellipse by half. A plurality of lens portions 52m are disposed at a fixed interval on the back surface 51 of the main body portion 51m. Specifically, a square lattice formed by arranging a plurality of squares is set with respect to the back surface 51, and is formed as a constituent unit of the square lattice. The square portion is arranged with one lens portion %. The occupancy ratio of the lens portion % to the constituent unit of the square lattice (the coverage ratio of the lens portion % to the constituent unit) is set to 78.5. /£^ is a square unit of the square lattice The length of one side is set to 500 μη. In the simulation, first, a lens portion 52 having an outer shape defined by the formula (1) is designed. Imagine a light guide plate 5 μ having a designed lens portion 52 μ, a self-point light source In the case where the incident light is 61 μ, the center portion of the light-emitting surface 5 〇Μ 2 exit surface HMa is assumed to be the point p at which the light is emitted, and the light is emitted from the point p. The radiance of the emitted light. Then set the local xyz coordinate system shown in Figures 3(b) and (c) to calculate the amount of light Q and the amount of light Q2. In the simulation, 'for comparison with the following 161699 .doc -24- 201235718 The results are compared. The multiple points on the hemisphere are calculated as 02K90 and 0%b 360. The range is equivalent to the hemisphere of the area in the sphere of the unit sphere shown in the figure. The radiance of the outgoing light emitted from the surface. Then, based on the calculated radiance, # is the total radiation beam of the hemispherical surface and the radiation beam of the specific area. The above multiple points of the radiance of the nucleus are calculated to include the specific area. In the way of the point, the amplitude is set every 5 degrees along the Θ direction and the amplitude is set to 胄 in every direction. The total light beam and the light beam system are calculated according to the light #luminance as follows. That is, the radiance of each calculated point is converted into a radiation beam per unit solid angle. The unit solid angle is set to 1/4; secondly, each radiation beam is converted into a radiation beam of each of the surface elements on the unit sphere. Thereafter, the whole is over the hemisphere The radiation beam of each surface element on the unit sphere is numerically integrated to calculate the total radiation beam. The value of the radiation beam of each surface element on the unit sphere is calculated in the range of 25.$0$35 and _5.^. Integral to calculate the radiation beam. In the simulation, the radiation beam is calculated as a physical quantity, and the radiation beam corresponds to the luminous flux of the so-called psychophysical quantity (the amount of light per unit time). Thus, the radiation beam of a specific region is relative to the calculated total radiation. The ratio of the beam corresponds to the ratio of the luminous flux (the amount of light per unit time) to the total luminous flux (the total amount of light per unit time) of a specific region. Thus, the [radiation beam of a specific region] / [total radiation beam] is set to Light amount ratio Q. By changing ka&ha/Wa, the above simulation is performed on the shape of the plurality of lens portions 52m to be set, and the light amount ratio Q is calculated. For comparison, a light amount ratio Q based on the measured value of 161699.doc -25·201235718 is obtained using the light guide plate 8 having the white point 81. In the experiment for comparison (hereinafter referred to as "comparative experiment"), the backlight unit used in "UN46B8000" manufactured by Samsung Electronics Co., Ltd. was taken out, and the light guide plate of the backlight unit was used as the light guide plate 80. Then, a light guide plate 8 and a light source of the backlight unit are used, and a silver vapor deposition reflective film is provided on the back side of the light guide plate 80, whereby the same configuration as that of Fig. 9 is realized. The light guide plate 80 used in the comparative experiment has a white point 81. Further, in the comparative experiment, white light was supplied from the side surface of the light guide plate 8 to the light guide plate 80 in the same manner as in the case of the simulation model shown in Fig. 9, and the position from the exit surface 51a was measured (light guide plate 8A). The brightness of the central position). The measurement was carried out using a luminance meter ("Color Luminance Meter BM-5 AS" manufactured by T〇pc〇M Co., Ltd.). Specifically, the luminance is measured at a plurality of measurement points in the hemispherical surface of the region corresponding to the spherical surface shown in Fig. 3(b). A plurality of measurement points are set so as to correspond to the calculated points of the simulated radiance. Based on the measured luminance, the total luminous flux and the luminous flux of the specific region were calculated in the same manner as in the case of the simulation. That is, the luminance of each measurement point is converted into a luminous flux per unit solid angle. The unit solid angle is set to 1/4π. The -person' converts the luminous flux into the luminous flux of each of the surface elements on the unit sphere. Thereafter, the luminous flux of each of the surface elements on the unit spherical surface is numerically integrated over the hemispherical surface to calculate the total luminous flux. 35 at 25°$θ. And -5. ^ 0^5. Within the range, the luminous flux of each of the surface elements on the unit sphere is numerically integrated to calculate the luminous flux of the specific area. The luminous flux corresponds to the amount of light per unit time, so that the luminous flux corresponding to the specific region of the luminous quantity Qi' corresponds to the amount of light 仏. Thus, the amount of light is calculated by dividing the amount of light 161699.doc •26-201235718 by the amount of light Q!'. When the white point 81 is set, the light amount ratio Q is 0.252%. The simulation results are shown in the graphs shown in Figures 11 and 12. Fig. 11 and Fig. 12 are graphs showing the relationship between the lens shape and the light amount ratio Q defined by the equation (1) and the aspect ratio [ha/wa]. Fig. 11 shows that ka is in the range of 〇 or more to 0.9, and Fig. 12 shows that ka is in the range of -0.9 or more and -〇·1 or less. In FIGS. 11 and 12, the light amount ratio Q is larger than the exit angle 30. There are more lights coming out nearby. In other words, when the light amount ratio q is larger than the prism plate 4〇μ, the brightness can be improved. 13 and FIG. 14 show the ratio [r/Wa] of the radius of curvature r to the width wa of the end portion 52Ma of the lens shape defined by the angles [ha/wa] shown in FIGS. chart. Further, Fig. 15 and Fig. 16 are graphs showing the bottom angles of the lens shapes defined by ka and the aspect ratio [ha/Wa] shown in Figs. In the graphs shown in FIG. 11 and FIG. 12, the light amount ratio Q larger than the value (0.252%) of the light amount ratio Q calculated for the white point 81 is underlined, and FIG. 13 and FIG. 15 corresponding to FIG. In Fig. 14 and Fig. 16 corresponding to Fig. 12, the curvature radius of the distal end portion 52a of the lens portion 52 in which the light amount ratio Q is underlined in Figs. 11 and 12 is [r/Wa] and the bottom portion with respect to the width %. The angle γ is underlined. Therefore, in FIG. 11 to FIG. 16, in the lens portion 52 defined by the underlined ha/Wa and the radius of curvature with respect to the width Wa2 [r/Wa] and the bottom angle γ, a white point 81 can be realized. In the case of the light guide plate 8 大, the amount of light is larger than Q. 161699.doc •27- 201235718 Moreover, the aspect ratio [ha/wa] of the shape of the predetermined lens portion 52m underlined in FIGS. 11 to 16 and the [r/Wa] and the bottom angle of the curvature radius with respect to the width % are shown. γ is within the range shown in the graph shown in Fig. 5. Therefore, in the light guide plate 50 having the lens portion 52 defined by the combination of ha/Wa, r/w, and γ shown in Fig. 5, the exit angle 0 is obtained. Easy to become 25. Above 35. the following. As described above, by using the light guide plate 50 of the present embodiment, the transmissive image display unit 2 can be illuminated with higher brightness in the transmissive image display device 1 having the prism plate 4?. As a result, the brightness of the image displayed by the transmissive image display unit 2 can be improved. The embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit and scope of the invention. In the above embodiment, it is assumed that a plurality of lens portions 52 formed on the back surface 5 1 b have a shape in which the light amount ratio Q is larger than 252.252%. However, at least half or more of the plurality of lens portions formed on the back surface 51b may be the lens portion 52 described in the above embodiment. In other words, the plurality of lens portions formed on the back surface 51b may include a second lens portion in which half of the lens portion 52 is the first lens portion and the remaining half is a condition that does not satisfy the conditions described in the above embodiments. The ratio of the number of the first lens portions of the lens portion 52 to the number of the second lens portions may be 6: 4. The shape of the lens portion 52 is preferably as illustrated in FIG. 4 and has a shape, that is, a lens. The angle formed by the junction of the portion 52 and the back surface 51|5 monotonously decreases from the bottom side to the front end side of the lens portion 52. However, the lens portion 52 has a shape defined by a combination of ha/Wa, r/w & y which is not shown in FIG. 5 of 161699.doc -28-201235718, and thus has a light amount ratio Q greater than 0, 252%. The shape may be such that the angle formed by the contact surface of the lens portion 52 and the moon surface 51b is not monotonously reduced to the side of the front end portion 52a. Further, the number of the light source units 60 is not limited to two. For example, there are three or more light source sections. In this case, for example, the light source portion 60 may be further provided to at least one of the side faces 51e, 5 If which the body portion $1 has. The light source unit 60 may be provided with one of the light guide plates. The light source unit 60 is disposed in one of the side surface 51c and the side surface 5id shown in Fig. i. In the transmissive image display device 1 shown in FIG. 1, as long as the purpose of the present month is not impaired, another optical member may be disposed between the light guide plate 5 and the seesaw, or the seesaw 4 may be disposed. Another optical member is disposed between the 〇 and the transmissive image display unit 1A. Another example of the optical member provided between the light guide plate 5A and the dam plate 40 is a light diffusion sheet or a microlens sheet having a light diffusion property to the extent that the object of the present invention is not impaired. Another example of the optical member provided between the seesaw 4 and the transmissive image display unit 1 is a reflective polarized separation sheet, a light diffusion sheet or a microlens sheet. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing a schematic configuration of a transmissive image display device according to an embodiment of a light guide plate of the present invention. Fig. 2 is a plan view showing a state in which the light guide plate shown in Fig. 观察 is viewed from the side of the surface. Fig. 3 is a diagram for explaining the shape of the lens portion. Fig. 3 (the phantom system shows the setting state of the coordinate system of the station # on the exit surface, and Fig. 3(b) is used to say 161699.doc -29 · 201235718 A diagram showing the method of specifying the angle calculated from the z-axis and the x-axis in the coordinate system shown in Fig. 3 (4), Fig. 3 (4) is used to illustrate the pattern of the material region. Figure 4 is a diagram for explaining the lens portion. Fig. 5 is a view showing a condition for defining a shape outside the lens portion. Fig. 6 is a partially enlarged view of the transmissive image display device shown in Fig. 1. Fig. 7 is a view showing (four) white Fig. 8 is a graph showing the measurement results of the intensity distribution of the light emitted from the exiting W. Fig. 9 is a schematic diagram showing the simulation model. Fig. 11 is a graph showing the relationship between the lens shape and the light amount ratio used in the simulation. Fig. 12 is a graph showing the relationship between the lens shape and the light amount ratio used in the simulation. Figure β Figure 13 shows the aspect ratio shown in Figure u A graph showing the radius of curvature Γ with respect to the width % of the front end portion of the lens shape. Fig. 14 is a view showing the radius of curvature of the end portion of the lens shape defined by the angle ratio [ha/Wa] shown in Fig. 12 A chart of width %.
圖15係表示由圖Η所示之!^與縱橫比[ha/wa]規定之透鏡 形狀之底部角度之圖表Q 圖16係表示由圖12所示之1與縱橫比[ha/Wa]規定之透鏡 形狀之底部角度之圖表。 【主要元件符號說明】 161699.doc 30· 201235718 10 透過型圖像顯示裝置 20 透過型圖像顯示部 21 液晶早元 22 直線偏光板 • 23 直線偏光板 30 面光源裝置 40 稜鏡板 40a 表面（稜鏡板之單面） 40b 背面（稜鏡板之與單面為相反側之面） 41 稜鏡部 41a 稜鏡部之頂部 42a 側面 42b 側面 50 導光板 50a 側面 50b 側面 5 〇m 導光板 5 0 jvjb 側面 ' 51 本體部 51a 出射面（第1面） 51b 背面（第2面） 51c 側面（入射面） 51d 側面（入射面） 51e 側面 161699.doc -31 - 201235718 51f 側面 51m 本體部 5 1 m a 出射面 5 1 Mb 背面 5 lMc 側面 5 1 ivjd 側面 5 1 m6 側面 51Mf 側面 52 透鏡部 52a 前端部 52b 底部 52m 透鏡部 5 2]^a 前端部 60 光源部 6〇m 光源部 61 點狀光源 61m 點狀光源 70 反射部 7〇m 反射部 80 導光板 81 白點 C 中心軸線 ha 厚度 P 接面 -32- 16I699.doc 201235718 P 點 r 曲率半徑 t 本體部之厚度 W1 導光板之長邊之長度 W2 導光板之短邊之長度 wa 寬度 X 方向 X 座標軸 Y 方向 y 座標軸 z 方向 z 座標軸 a 頂角 Θ 角度（偏角） Φ 角度（偏角） y 角度 θ〇 出射角 0i 入射角 161699.doc -33-Fig. 15 is a graph showing the bottom angle of the lens shape defined by Fig. 与 and the aspect ratio [ha/wa]. Fig. 16 is a view showing the 1 and the aspect ratio [ha/Wa] shown in Fig. 12. A graph of the bottom angle of the lens shape. [Description of main component symbols] 161699.doc 30· 201235718 10 Transmissive image display device 20 Transmissive image display unit 21 Liquid crystal early element 22 Linear polarizing plate • 23 Linear polarizing plate 30 Surface light source device 40 Plate 40a Surface (rib One side of the mirror plate) 40b The back side (the side of the seesaw opposite to the single side) 41 稜鏡 41a 稜鏡 top 42a side 42b side 50 light guide 50a side 50b side 5 〇m light guide 5 0 jvjb side ' 51 Main body part 51a Exit surface (first surface) 51b Back surface (2nd surface) 51c Side surface (incident surface) 51d Side surface (incident surface) 51e Side surface 161699.doc -31 - 201235718 51f Side surface 51m Main body part 5 1 ma Exit surface 5 1 Mb Back 5 lMc Side 5 1 ivjd Side 5 1 m6 Side 51Mf Side 52 Lens 52a Front end 52b Bottom 52m Lens part 5 2) ^ Front end 60 Light source part 6〇m Light source part 61 Point light source 61m Point Light source 70 Reflecting part 7〇m Reflecting part 80 Light guide plate 81 White point C Center axis ha Thickness P Joint surface-32- 16I699.doc 201235718 P point r Curvature half Diameter t Thickness of the body part W1 Length of the long side of the light guide plate W2 Length of the short side of the light guide plate Width X Direction X coordinate axis Y direction y coordinate axis z direction z coordinate axis a apex angle 角度 angle (angular angle) Φ angle (angular angle y angle θ 〇 exit angle 0i incident angle 161699.doc -33-