201005227 九、發明說明 【發明所屬之技術領域】 本發明，是有關導光體及線狀光源裝置，使用於：傳 真機、影印機、掃描機、讀條碼機等中的畫像讀取裝置用 的照明用光源、及設有液晶面板的導光板的背部光源用的 端緣照明用光源等。 φ 【先前技術】 近年來，對於個人傳真機等的畫像讀取裝置，因爲發 光二極管（以下稱LED)的高輸出化及作爲受光元件的CCD 型感測器的高靈敏度化，小型且低消耗電力的LED已被 作爲讀取光源裝置的光源使用。已知將這種LED作爲光 源的習知的線狀光源裝置，爲了降低光源的個數且獲得均 一的照明強度的目的，而使用導光體，並將從光源放射的 光入射至導光體讓光朝所期的方向被導光。 〇 第8圖，是顯示習知的線狀光源裝置的曰本特開平9- 1 63 080號公報所揭示的線狀光源裝置的結構的圖。 線狀光源裝置是具備：由透明樹脂等構成的導光體1 、由LED構成的光源2。導光體1，是在軸方向的一端設 有光取入部3，於另一端設有形成反射膜的平滑面4。光 源2，是配置成對峙於光取入部3。且，在導光體1的照 射方向相反側的外周面，設有朝軸方向延伸的壓花溝5。 壓花溝5，其切入方向是與軸方向垂直，沿著軸方向的剖 面是成爲二等邊三角形形狀。 -5- 201005227 光源2的射出光，是從光取入部3入射至導光體1的 內部，在導光體1內返覆反射，並反射至壓花溝5的反射 面6後，以預定的角度從導光體1射出。 光源2的射出光之中，對於光取入部3的入射角較大 的光αΐ，是被接近光取入部3的壓花溝5的反射面6所 反射（光α 2)。對於光取入部3的入射角較大的光〇:1，因 爲對於壓花溝5的反射面6的入射角較小（光α 2)，所以能 φ 以接近垂直的（朝平滑面4方向若干傾斜）射出角度從導光 體1射出（光α 3)。 另一方面，光源2的射出光之中，對於光取入部3的 入射角較小的光/31，是沿著導光體1的軸方向進入，並 被由遠離光取入部3但接近平滑面4的壓花溝5的反射面 6所反射（光Θ 2)。對於光取入部3的入射角較小的光万1 ，因爲對於壓花溝5的反射面6的入射角較大（光沒2)，所 以以具有朝平滑面4方向傾斜的角度從導光體1射出（光 ❹ 0 3)。 [專利文獻1]日本特開平9-163080號公報 【發明內容】 (本發明所欲解決的課題） 但是，如第8圖所示的線狀光源裝置，因爲是射出具 有朝平滑面4方向傾斜的角度的光^3，所以在讀取畫像 中會有產生黑紋的情況。第9圖，是爲了說明影44而顯 示讀取對象42及光線的畫像讀取裝置的一部分剖面圖。 -6- 201005227 在畫像讀取裝置中，設有相面對於線狀光源裝置的光 射出面9且由光透過性構件構成的載置面41，將記載有欲 取入的畫像的讀取對象42載置於載置面41來使用。從導 光體1的光射出面9射出的光是對於載置面41進行照射 ，將檢出的讀取對象42的投影像作爲讀取畫像。 書籍等具有厚度的讀取對象42時，會在讀取對象42 的光照射面及原稿蓋43之間產生厚度。因爲光不會透過 φ 讀取對象42，所以照射讀取對象42的端部的光0 3a不會 照射原稿蓋43。從照射讀取對象42的端部的光^ 3a朝軸 方向稍爲偏離照射的光；3 3b，雖是照射原稿蓋43，但是因 爲具有角度，所以會從讀取對象42的端朝軸方向偏離地 照射。因此，光33a及光03b之間，不會被光照射而產 生影44，在讀取畫像會顯示黑紋。 且，同樣地於讀取對象42具有曲折線等的段差的情 況時也會發生。 φ 本發明，是鑑於上述的問題點，其目的爲提供一種光 導光體及線狀光源裝置，即使在讀取對象具有厚度或段差 的情況，也能由不會在讀取畫像出現黑紋的方式放射光。 (解決上述課題的手段） 本案第1發明，是一種導光體，是棒狀的導光體，其 軸方向的一方的端部是成爲光取入部，且在側面形成朝軸 方向延伸的壓花溝，其特徵爲：前述壓花溝具有複數溝部 ，前述溝部的光取入部側的側面是成爲反射面，前述溝部 -7- 201005227 之中至少1條溝部的反射面是由1次反射面及2次反射面 所構成。 且，本案第2發明，是如第1發明，在前述1次反射 面的軸方向端部形成前述2次反射面，前述2次反射面的 傾斜角度是比前述1次反射面的傾斜角度大。 且，本案第3發明，是如第1發明，前述溝部’是由 前述反射面、平坦面及透光面所構成，具有由前述1次反 φ 射面及前述2次反射面構成的前述反射面的前述溝部的前 述透光面，是由1次透光面及2次透光面所構成。 且，本案第4發明，是如第3發明，在前述2次透光 面的軸方向端部形成前述1次透光面，前述2次透光面的 傾斜角度是比前述1次透光面的傾斜角度大。 且，本案第5發明，是如第1發明，前述溝部，是由 前述反射面、平坦面及透光面所構成，前述平坦面是從軸 方向朝逆時針方向傾斜。 φ 且，本案第6發明，是一種線狀光源裝置，其特徵爲 ，具有：如第1〜5項之中任一項的導光體、及相面對設 置於前述導光體的前述光取入部之光源。 [發明的效果] 依據本發明的導光體及線狀光源裝置，因爲壓花溝的 溝部的反射面藉由1次反射面及2次反射面構成，而可從 線狀光源裝置朝向讀取對象射出在軸方向具有不同的2個 角度成分的光，所以即使在讀取對象具有厚度或段差的情 -8- 201005227 況也不會在原稿蓋發生影’就不會在讀取畫像出現黑紋。 【實施方式】 說明本發明的第1實施例。第1圖，是顯示本發明的 線狀光源裝置的結構的立體圖。 線狀光源裝置是具備：由透明樹脂等構成的導光體1 ，由LED構成的光源2。導光體1，是由圓柱狀的零件’ φ 在軸方向的一端設有光取入部3’另一端是成爲平滑面4 。在成爲導光體1側面的外周面，設有朝軸方向延伸的壓 花溝5，相面對於壓花溝5的位置是成爲光射出面9。壓 花溝5，是複數形成有切入方向與導光體1的軸方向垂直 的溝部7。 光源2，是在例如由樹脂藉構成的封裝盒內部，配置 1至複數個藍色LED元件，藉由塑模材固定藍色LED保 護使與外氣遮斷，藉由螢光體層將來自藍色LED的藍色 φ 光變換成白色光。又，一般，LED元件對於光輸出會參差 不一，但是在光源2配置複數LED元件的情況時，光源2 的光輸出，不會影響各LED元件的光輸出，而可以確保 一定的光輸出。光源2，是對峙於光取入部3地配置。 從光源2射出的光，是具有完全擴散面光源的配光分 布，朝向導光體1照射。來自光源2的射出光是入射至高 曲折質媒體的情況時，依據反射法則，成爲曲折角度較小 的光線。例如，來自光源2的射出光，是通過空氣入射至 曲折率n= 1.49的導光體1時’入射面是對於導光體1的 -9- 201005227 中心軸爲垂面的話，入射角度即使是89°的光線，對於導 光體1的軸的42°傾斜光線，即對於導光體1的側面（外周 面）的入射角度是成爲48°，超過臨界角。因此，導光體的 側面是由鏡面對於軸平行的話，入射至導光體1的光，可 全部被全反射而無損失地被導光。 第2圖，是顯示將本發明的線狀光源裝置朝軸方向X 切斷的擴大剖面圖。 φ 壓花溝5，是與導光體的軸方向X垂直，且設有複數 從壓花溝5朝光射出面9前進的徑方向Y切入的溝部7, 在各溝部7的頂部形成平坦面8。在導光體1內被導光的 光量，因爲是隨著從光取入部3遠離而減少，所以平坦面 8的軸方向X的長度會隨著遠離光取入部3而變短，由壓 花溝5反射的光量，可橫跨軸方向整體皆均一。且，爲了 讓光量更均一，也有使各溝部7的徑方向Y的長度隨著從 光取入部3附近接近平滑面4附近漸深地形成，且溝部7 φ 的寬度漸廣。 從光源2入射的光，是一邊反射導光體1內壁，一邊 到達壓花溝5，對於反射面6的入射角是超過臨界角的情 況時是全反射進入光射出面9，從導光體1朝外部射出。 對於光取入部3的入射角較大的光A1，是被接近光取入 部3的壓花溝5的反射面6所反射。入射光A1，因爲是 對於壓花溝5的反射面6的入射角較小，所以對於光射出 面9幾乎朝垂直方向被全反射。對於光取入部3的入射角 較小的光B1，是沿著導光體1的軸方向X前進，並遠離 -10- 201005227 光取入部3，由接近平滑面4的壓花溝5的反射面6所反 射。入射光B1’因爲是對於壓花溝5的反射面6的入射 角較大，所以是由具有從光取入部3朝平滑面4前進的軸 方向X傾斜的角度被反射。 第3圖，是顯示將本發明的導光體1沿著如第2圖所 示的線A-A’朝徑方向Y切斷的投影圖。實線是顯示線A-A·的導光體1的形狀，虛線是顯示壓花溝5的溝部7。 φ 導光體1的徑方向的剖面，不是完全圓形，一部分設 有直線部。由導光體1整體來看的話，在外周面設有朝軸 方向延伸的水平面。壓花溝5，是設在此水平面。因爲該 水平面可以容易進行高精度的溝加工。 壓花溝5，是形成橫跨寬度方向Z朝徑方向Y以同一 長度切入的溝部7。在徑方向Y及寬度方向Z的平面的投 影圖中，溝部7是成爲梯形狀。 第4圖，是顯示將本發明的導光體的壓花溝5朝軸方 φ 向X切斷的各溝部7的擴大剖面圖。 各溝部7的光取入部3側的側面是成爲反射面6，平 滑面4側的側面是成爲透光面10。反射面6，是由1次反 射面11及2次反射面12所構成，在1次反射面11的軸 方向X端部形成2次反射面12。溝部7，是在從光取入部 3前進平滑面4的軸方向X，形成朝徑方向Y沒入的1次 反射面11，延續1次反射面11形成2次反射面12，延續 2次反射面12形成平坦面8，延續平坦面8形成朝徑方向 Y的相反方向突出的透光面10。即，溝部7，是朝向軸方 -11 - 201005227 向X依序形成1次反射面11、2次反射面12、平坦面8、 透光面1 0。 Θ1是表示從軸方向X直到1次反射面n爲止朝逆 時針旋轉時的角度’ 02是表示從軸方向X的180。的相反 方向直到透光面10爲止朝順時針旋轉時的角度，03是表 示從軸方向X直到2次反射面12爲止朝逆時針旋轉時的 角度。 φ 爲了使來自光源2的光至少一半以上被導光體1全反 射而同行’有需要使從光源2以45。射出的光，即使在導 光體1內對於導光體1的軸具有28。的傾斜的光被全反射 。因此，1次反射面11的傾斜角度01，是在光取入部3 附近形成20°。且，透光面1〇的傾斜角度02，是不與具 有28°傾斜的光接觸地形成28°以上。 2次反射面12的傾斜角度03是比1次反射面11的 傾斜角度01大。因此’由1次反射面11所反射的光會發 生再度反射至2次反射面12的情況。 入射至位於遠離2次反射面12位置的1次反射面11 的光A1’是作爲具有朝軸方向X傾斜的角度的光A2被反 射。另一方面’入射至2次反射面12附近的1次反射面 11的光B1’是由2次反射面12再度被反射，作爲具有朝 軸方向X的相反方向傾斜的角度的光B2被反射。傾斜角 度Θ 3是75°〜90°的話，射出光B2會朝較佳方向前進。 因爲反射面6是由1次反射面11及2次反射面12所 構成’所以從光源朝導光體內部以單一方向前進的光A1 -12- 201005227 、B1即使被導光，也會被反射面6所反射而成爲朝2方 向前進的光A2、B2。爲了讓光A2及光B2的光量具有適 當的比率，雖可適宜地進行調整，但是2次反射面12的 高度是可讓具有15°〜20°傾斜的光的一半程度可碰撞於2 次反射面1 2較佳。 第5圖，是顯示光線A2、B2照射於讀取對象42的狀 態的畫像讀取裝置的一部分剖面圖。 φ 如第4圖所示由反射面6所反射的光A2、B2，是透 過光射出面9朝導光體1的外部射出，照射第5圖所示的 讀取對象42。在畫像讀取裝置中，設有相面對於線狀光源 裝置的光射出面9且由光透過性構件構成的載置面41，將 記載有欲取入的畫像的讀取對象42載置於載置面41來使 用。從導光體1的光射出面9射出的光是對於載置面41 進行照射。畫像讀取裝置，是將記載有欲取入的畫像的讀 取對象42載置於載置面41 ’檢出被載置於載置面41的讀 • 取對象42的投影像作爲讀取畫像。 書籍等具有厚度的讀取對象42時，會在讀取對象42 的光照射面及原稿蓋43之間產生厚度。因爲光不會透過 讀取對象42，所以，具有朝軸方向X傾斜的角度成分的 光A2會照射讀取對象42的端部而不會照射原稿蓋43。 但是，具有朝軸方向X相反方向傾斜的角度成分的光B2 ，可照射到光A2無法照射到原稿蓋43的位置，所以不會 發生光未被照射的影。 同樣地於讀取對象42具有曲折線等的段差的情況也 -13- 201005227 適用。 因此，因爲藉由讓壓花溝5的溝部7的反射面6由1 次反射面11及2次反射面12構成’可以從線狀光源裝置 將在軸方向X具有2個不同角度成分的光朝向讀取對象 42射出，所以即使在讀取對象42具有厚度或段差的情況 也不會在原稿蓋43發生影，就不會在讀取畫像中出現黑 紋。 φ 說明本發明的第2實施例。第6圖，是顯示本發明的 導光體的壓花溝5的各溝部7的擴大剖面圖。 第2實施例，是對於第1實施例的線狀光源裝置，變 更壓花溝5的溝部7形狀。形成有由一面構成的反射面6 之溝部7a、及形成有由1次反射面11及2次反射面12構 成的反射面6之溝部7b是交互地形成。溝部7b，是從溝 部7a的平坦面8朝徑方向Y沒入的矩形狀的溝。形成於 溝部7b的2次反射面12與第1實施例的2次反射面12 0 相比’朝徑方向Y的沒入長度變大，其表面積也變大。且 ’形成於溝部7b的透光面10也由1次透光面13及2次 透光面14所構成。1次透光面13的傾斜角度04，是表示 從軸方向X的相反方向直到1次透光面13爲止的順時針 旋轉時的角度’與溝部7a的透光面1〇的傾斜角度略 同一。2次透光面14’是設成相面對於2次反射面12。2 次透光面14的傾斜角度05’是表示從軸方向X的相反方 向直到2次透光面14爲止的順時針旋轉時的角度，比1 次透光面13的傾斜角度04大。 -14 - 201005227 溝部7a，是在軸方向X形成朝徑方向γ沒入的反射 面6，延續反射面6形成平坦面8，延續平坦面8形成朝 徑方向Υ的相反方向突出的透光面10。即，溝部7a，是 朝向軸方向X依序形成反射面6、平坦面8、透光面10。 另一方面，溝部7b，是在軸方向X形成朝徑方向γ 沒入的1次反射面11，延續1次反射面11形成續2次反 射面12，延續2次反射面12形成平坦面8，延續平坦面8 φ 形成朝徑方向Y的相反方向突出的2次透光面14，延續2 次透光面14形成1次透光面13。即，溝部7b，是朝向軸 方向X依序形成1次反射面11、2次反射面12、平坦面8 、2次透光面14、1次透光面13。 入射至溝部7a的反射面6的光A1，是作爲具有朝軸 方向X傾斜的角度的光A2被反射。另一方面，入射至溝 部7b的1次反射面11的光B1，是藉由加長2次反射面 12的朝徑方向Y沒入的長度（高度）就可無關朝1次反射面 φ 11的入射角度或入射位置，大致再度被反射，作爲具有朝 軸方向X的相反方向傾斜的角度的光B2被反射。光A1 入射至反射面6的高度、及光B1入射至1次反射面丨丨的 筒度是略同一，但是被反射的光A2、B2是朝不同方向前 進。 且，從比光Al、B1高的位置照射至溝部7b的光C1 ，是入射至2次反射面12»因爲2次反射面12的傾斜角 度大，所以光C1的入射角度比臨界角小，光C1會透過2 次反射面12。光C1的透過光會從2次透過面14再度入 -15- 201005227 射至導光體內部，成爲朝軸方向X被導光的光C2。 如此，形成有由一面構成的反射面6之溝部7a、及形 成有由1次反射面11及2次反射面12構成的反射面6之 溝部7b藉由交互地形成，即使從光源朝導光體內部以單 —方向前進的光Al、B1被導光，仍可將由溝部7a的反射 面6所反射的光A2、及由溝部7b的1次反射面11及2 次反射面12所反射的光B2，即具有朝軸方向X不同2方 φ 向的角度成分的光A2、B2朝向讀取對象42射出。且，因 爲透過2次反射面12的光C1也再度入射至導光體內部， 成爲朝軸方向X被導光的光C2，所以可以效率佳地利用 光。 又，形成有由一面構成的反射面6之溝部7a、及形成 有由1次反射面11及2次反射面12構成的反射面6之溝 部7b之間的形成間隔，不是交互形成也可以，在複數形 成有由一面構成的反射面6之溝部7a形成處只適當插入 φ 形成有由1次反射面11及2次反射面12構成的反射面6 之溝部7b的數量的壓花溝5也可以。且，相反也可能。 對於原稿蓋爲了防止在讀取對象的端部發生影，而在 導光體的軸方向X的平滑面側的一部分的壓花溝5的溝部 7，具有上述形成有由1次反射面11及2次反射面12構 成的反射面6之溝部7b也可以。 對於本發明的第3實施例說明。第7圖是顯示本發明 的導光體的壓花溝5的溝部7的一部分擴大剖面圖。第7 圖（a)是顯示如第6圖所示溝部7a的將平坦面8從軸方向 -16- 201005227 X朝逆時針傾斜形成的情況，第7圖（b)是顯示如第6圖 示溝部7b的2次反射面12及2次透過面14的傾斜角 爲9(Γ以下的情況。 如第7圖（a)所示，第3實施例，是對於第2實施例 線狀光源裝置，將溝部7a的平坦面8從軸方向X朝逆 針傾斜形成。平坦面8，是以與反射面6的接點爲支點 軸方向X朝逆時針稍爲旋轉的狀態的方式形成。光A1 φ 入射至平坦面8時，與平坦面8朝軸方向X平行的情況 比，入射角度0a變小。光A1是在平坦面8由對應於 射角度0a的角度被全反射而成爲光A2。光A2的與軸 向X的角度0b，是比平坦面8與軸方向X平行的情況 比較大，光A2是可以加大徑方向Y的角度成分。 如第7圖（b)所示，第3實施例，是對於第2實施例 線狀光源裝置，溝部7b的2次反射面12及2次透過面 的傾斜角度爲90°以下。2次反射面12的傾斜角度03 φ 90°以下的話，光B1反射至1次反射面11並入射至2 反射面12時，對於2次反射面12的入射角度0d，與 次反射面12的傾斜角度03爲90°的情況相比變大。2 反射面12的射出光B2，因爲射出角度也對應入射角度 d，所以與徑方向Y的角度0 e變小。光B 2，與傾斜角 0 3爲90°的情況相比，因爲軸方向X的相反方向的角 成分變小，徑方向Y的角度成分變大，所以成爲朝接近 方向Y的方向前進。 所 度 的 時 從 是 相 入 方 相 的 14 爲 次 2 次 Θ 度 度 徑 -17- 201005227 【圖式簡單說明】 [第1圖]本發明的線狀光源裝置的結構的立體圖 [第2圖]本發明的線狀光源裝置的擴大剖面圖 [第3圖]將本發明的導光體朝徑方向切斷的投影圖 [第4圖]本發明的導光體的壓花溝的各溝部的擴大剖 面圖 [第5圖]光線照射於讀取對象的狀態的畫像讀取裝置 φ 的一部分剖面圖 [第6圖]本發明的導光體的壓花溝的各溝部的擴大剖 面圖 [第7圖（a)(b)]本發明的導光體的壓花溝的溝部的一部 分擴大剖面圖 [第8圖]習知的線狀光源裝置的結構的剖面圖 [第9圖]光線照射於讀取對象的狀態的畫像讀取裝置 的一部分剖面圖 【主要元件符號說明】 1 :導光體 2 :光源 3 :光取入部 4 :平滑面 5 :壓花溝 6 :反射面 7 :溝部 -18- 201005227 7a :溝部 7b :溝部 8 :平坦面 9 :光射出面 10 :透光面 1 1 : 1次反射面 1 2 : 2次反射面 1 3 : 1次透光面 14 : 2次透光面 4 1 :載置面 42 :讀取對象 43 :原稿蓋 44 :影201005227 IX. OBJECT OF THE INVENTION [Technical Field] The present invention relates to a light guide and a linear light source device for use in an image reading device such as a facsimile machine, a photocopying machine, a scanner, a bar code reader, or the like. A light source for illumination, and a light source for edge illumination for a back light source provided with a light guide plate of a liquid crystal panel. φ [Prior Art] In recent years, the image reading device such as a personal facsimile machine has a high output of a light-emitting diode (hereinafter referred to as LED) and a high sensitivity of a CCD sensor as a light-receiving element, and is small and low-consumption. Electric power LEDs have been used as light sources for reading light source devices. A conventional linear light source device using such an LED as a light source is known, and a light guide body is used for the purpose of reducing the number of light sources and obtaining uniform illumination intensity, and light emitted from the light source is incident on the light guide body. Let the light be guided in the direction of the desired direction. Fig. 8 is a view showing the configuration of a linear light source device disclosed in Japanese Laid-Open Patent Publication No. Hei 9-136080. The linear light source device includes a light guide 1 made of a transparent resin or the like, and a light source 2 made of an LED. The light guide 1 is provided with a light taking portion 3 at one end in the axial direction, and a smooth surface 4 for forming a reflecting film at the other end. The light source 2 is disposed to face the light taking portion 3. Further, an embossed groove 5 extending in the axial direction is provided on the outer peripheral surface of the light guide 1 on the side opposite to the irradiation direction. The embossed groove 5 has a cutting direction perpendicular to the axial direction, and a cross-sectional shape along the axial direction is a two-sided triangular shape. -5-201005227 The light emitted from the light source 2 enters the inside of the light guide 1 from the light taking portion 3, is reflected back in the light guide 1, and is reflected to the reflecting surface 6 of the embossing groove 5, and is predetermined. The angle is emitted from the light guide 1. Among the light beams emitted from the light source 2, the light α 较大 having a large incident angle with respect to the light taking-in portion 3 is reflected by the reflecting surface 6 of the embossing groove 5 close to the light taking portion 3 (light α 2 ). The pupil having a large incident angle with respect to the light taking-in portion 3 is 1 because the incident angle to the reflecting surface 6 of the embossed groove 5 is small (light α 2 ), so that φ can be nearly vertical (toward the smooth surface 4) A plurality of tilting) exit angles are emitted from the light guide 1 (light α 3). On the other hand, among the light emitted from the light source 2, the light/31 having a small incident angle with respect to the light taking-in portion 3 enters along the axial direction of the light guide 1, and is moved away from the light take-in portion 3 but is close to smooth. The reflecting surface 6 of the embossed groove 5 of the surface 4 is reflected (the aperture 2). Since the incident angle of the light incident portion 3 is small, since the incident angle to the reflecting surface 6 of the embossed groove 5 is large (the light is not 2), the light is guided at an angle inclined toward the smooth surface 4 Body 1 is emitted (light ❹ 0 3). [Patent Document 1] Japanese Laid-Open Patent Publication No. Hei 9-163080 (Explanation of the Invention) (The problem to be solved by the present invention) However, the linear light source device shown in Fig. 8 has an inclination toward the smooth surface 4 The angle of the light ^3, so there will be black streaks in the reading of the image. Fig. 9 is a partial cross-sectional view showing the image reading device for reading the object 42 and the light for explaining the shadow 44. -6-201005227 The image reading device is provided with a mounting surface 41 which is formed of a light-transmitting member on the light-emitting surface 9 of the linear light source device, and the object to be read is described. 42 is placed on the mounting surface 41 for use. The light emitted from the light exit surface 9 of the light guide 1 is irradiated onto the mounting surface 41, and the projected image of the read target 42 is taken as a read image. When a reading object 42 having a thickness such as a book is used, a thickness is generated between the light-irradiating surface of the reading object 42 and the document cover 43. Since light does not read the object 42 through φ, the light 0 3a that illuminates the end of the reading object 42 does not illuminate the document cover 43. The light 3 3a from the end portion of the illumination reading object 42 slightly deviates from the irradiated light in the axial direction; 3 3b illuminates the document cover 43 but has an angle from the end of the reading object 42 toward the axial direction Deviated from the ground. Therefore, between the light 33a and the light 03b, the shadow 44 is not generated by the light, and the black image is displayed when the image is read. Further, similarly, the reading object 42 also has a step of a zigzag line or the like. φ The present invention has been made in view of the above problems, and an object thereof is to provide a light guiding body and a linear light source device capable of not appearing black streaks in a read image even when a reading object has a thickness or a step. Way to emit light. (Means for Solving the Problem) The light guide according to the first aspect of the present invention is a rod-shaped light guide, and one end portion in the axial direction is a light take-in portion, and a side surface is formed to extend in the axial direction. The flower groove is characterized in that the embossed groove has a plurality of groove portions, and a side surface on the light-receiving portion side of the groove portion is a reflection surface, and a reflection surface of at least one of the groove portions -7-201005227 is a primary reflection surface And the second reflecting surface is composed of. According to a second aspect of the present invention, in the first aspect of the present invention, the secondary reflection surface is formed at an axial end portion of the primary reflection surface, and an inclination angle of the secondary reflection surface is larger than an inclination angle of the primary reflection surface. . According to a third aspect of the invention, the groove portion (the groove portion ′) is configured by the reflection surface, the flat surface, and the light transmission surface, and has the reflection formed by the primary reverse φ radiation surface and the secondary reflection surface The light transmitting surface of the groove portion of the surface is composed of a primary light transmitting surface and a secondary light transmitting surface. According to a third aspect of the present invention, in the third aspect of the present invention, the primary light-transmissive surface is formed at an end portion of the secondary light-transmissive surface in the axial direction, and the oblique angle of the secondary light-transmissive surface is larger than the primary light-transmitting surface. The angle of inclination is large. According to a fifth aspect of the invention, the groove portion is configured by the reflection surface, the flat surface, and the light transmission surface, wherein the flat surface is inclined counterclockwise from the axial direction. The present invention provides a linear light source device, comprising: the light guide according to any one of items 1 to 5, and the light facing the light guide; Take in the light source of the part. Advantageous Effects of Invention According to the light guide and the linear light source device of the present invention, since the reflection surface of the groove portion of the embossed groove is constituted by the primary reflection surface and the secondary reflection surface, the light source device can be read from the linear light source device. The object emits light having two different angular components in the axial direction, so even if the reading object has a thickness or a step difference - 8 - 201005227, it will not appear on the original cover. Pattern. [Embodiment] A first embodiment of the present invention will be described. Fig. 1 is a perspective view showing the structure of a linear light source device of the present invention. The linear light source device includes a light guide 1 made of a transparent resin or the like, and a light source 2 composed of an LED. The light guide body 1 is provided with a light-receiving portion 3' at one end in the axial direction by a cylindrical member 'φ', and the other end is a smooth surface 4. The outer peripheral surface which is the side surface of the light guide 1 is provided with an embossed groove 5 extending in the axial direction, and the position of the opposing surface to the embossed groove 5 is the light exit surface 9. The embossing groove 5 is formed with a plurality of grooves 7 having a cutting direction perpendicular to the axial direction of the light guiding body 1. The light source 2 is disposed inside the package box made of, for example, a resin, and is arranged with a plurality of blue LED elements, and the blue LED protection is fixed by the molding material to block the external air, and the phosphor layer will come from the blue The blue φ light of the color LED is converted into white light. Further, in general, the LED elements are different in light output. However, when the light source 2 is provided with a plurality of LED elements, the light output of the light source 2 does not affect the light output of each LED element, and a certain light output can be ensured. The light source 2 is disposed opposite to the light taking portion 3. The light emitted from the light source 2 is a light distribution distribution having a completely diffused surface light source, and is irradiated toward the light guide 1. When the emitted light from the light source 2 is incident on a highly meandering medium, it is a light having a small meander angle according to the reflection rule. For example, when the light emitted from the light source 2 is incident on the light guide 1 having a tortuosity of n= 1.49 through the air, and the incident surface is a vertical plane with respect to the central axis of the light guide body -9-201005227, the incident angle is even The light of 89°, the incident angle of 42° to the axis of the light guide 1, that is, the incident angle to the side surface (outer peripheral surface) of the light guide 1 is 48°, exceeding the critical angle. Therefore, when the side surface of the light guide body is parallel to the mirror surface, the light incident on the light guide body 1 can be totally reflected and totally guided without loss. Fig. 2 is an enlarged cross-sectional view showing the linear light source device of the present invention cut in the axial direction X. The φ embossed groove 5 is perpendicular to the axial direction X of the light guide, and is provided with a plurality of groove portions 7 cut in the radial direction Y from the embossed groove 5 toward the light exit surface 9, and a flat surface is formed on the top of each groove portion 7. 8. Since the amount of light guided in the light guide 1 decreases as it goes away from the light taking portion 3, the length of the flat surface 8 in the axial direction X becomes shorter as it goes away from the light taking portion 3, and is embossed. The amount of light reflected by the groove 5 can be uniform across the entire axis. Further, in order to make the amount of light more uniform, the length of the radial direction Y of each of the groove portions 7 is gradually increased from the vicinity of the smoothing surface 4 from the vicinity of the light taking portion 3, and the width of the groove portion φ is gradually increased. The light incident from the light source 2 reflects the inner wall of the light guide 1 and reaches the embossed groove 5, and when the incident angle of the reflecting surface 6 exceeds the critical angle, the total reflection enters the light exit surface 9 and is guided by the light. Body 1 is shot toward the outside. The light A1 having a large incident angle with respect to the light taking-in portion 3 is reflected by the reflecting surface 6 of the embossed groove 5 which is close to the light taking portion 3. Since the incident light A1 has a small incident angle with respect to the reflecting surface 6 of the embossed groove 5, the light emitting surface 9 is totally totally reflected in the vertical direction. The light B1 having a small incident angle with respect to the light taking-in portion 3 is advanced along the axial direction X of the light guide 1, and is away from the light-actracting portion 3 of -10-201005227, and is reflected by the embossed groove 5 close to the smooth surface 4. Reflected by face 6. Since the incident light B1' has a large incident angle with respect to the reflecting surface 6 of the embossed groove 5, it is reflected by an angle having an inclination in the axial direction X from the light taking-in portion 3 toward the smooth surface 4. Fig. 3 is a projection view showing the light guide 1 of the present invention taken along the line A-A' shown in Fig. 2 in the radial direction Y. The solid line is the shape of the light guide 1 of the display line A-A·, and the broken line is the groove 7 showing the embossed groove 5. The cross section of the φ light guide 1 in the radial direction is not completely circular, and a part is provided with a straight portion. When viewed from the entire light guide body 1, a horizontal plane extending in the axial direction is provided on the outer peripheral surface. The embossed groove 5 is located at this level. Because the horizontal plane can be easily processed with high precision grooves. The embossed groove 5 is formed into a groove portion 7 which is cut into the radial direction Y in the width direction Z and cut at the same length. In the projection view of the plane in the radial direction Y and the width direction Z, the groove portion 7 has a trapezoidal shape. Fig. 4 is an enlarged cross-sectional view showing each of the groove portions 7 in which the embossed grooves 5 of the light guide of the present invention are cut toward the axis φ to X. The side surface on the side of the light-receiving portion 3 of each of the groove portions 7 serves as the reflecting surface 6, and the side surface on the side of the smooth surface 4 serves as the light-transmitting surface 10. The reflecting surface 6 is composed of a primary reflecting surface 11 and a secondary reflecting surface 12, and a secondary reflecting surface 12 is formed at an end portion of the primary reflecting surface 11 in the axial direction X. The groove portion 7 is formed in the axial direction X of the smooth surface 4 from the light taking-in portion 3, and forms a primary reflecting surface 11 that is immersed in the radial direction Y. The primary reflecting surface 11 continues to form the secondary reflecting surface 12, and the secondary reflecting surface 12 is continued. The surface 12 forms a flat surface 8, and the continuous flat surface 8 forms a light-transmissive surface 10 that protrudes in the opposite direction of the radial direction Y. In other words, the groove portion 7 forms the primary reflecting surface 11, the secondary reflecting surface 12, the flat surface 8, and the light transmitting surface 10 in order toward the axis -11 - 201005227. Θ1 is an angle θ when the counterclockwise rotation is performed from the axial direction X to the primary reflection surface n. 02 is 180 indicating the axial direction X. The opposite direction is the angle when the light transmitting surface 10 is rotated clockwise, and 03 is the angle when the counterclockwise rotation is performed from the axial direction X to the secondary reflecting surface 12. φ In order to cause at least half of the light from the light source 2 to be totally reflected by the light guide 1, it is necessary to make the slave light source 2 at 45. The emitted light has 28 for the axis of the light guide 1 even in the light guide 1. The slanted light is totally reflected. Therefore, the inclination angle 01 of the primary reflecting surface 11 is formed at 20° in the vicinity of the light taking portion 3. Further, the inclination angle 02 of the light transmitting surface 1〇 is 28° or more without coming into contact with light having a 28° inclination. The inclination angle 03 of the secondary reflecting surface 12 is larger than the inclination angle 01 of the primary reflecting surface 11. Therefore, the light reflected by the primary reflecting surface 11 is reflected again to the secondary reflecting surface 12. The light A1' incident on the primary reflecting surface 11 located away from the secondary reflecting surface 12 is reflected as light A2 having an angle inclined in the axial direction X. On the other hand, the light B1' incident on the primary reflecting surface 11 in the vicinity of the secondary reflecting surface 12 is again reflected by the secondary reflecting surface 12, and is reflected as the light B2 having an angle inclined in the opposite direction to the axial direction X. . When the inclination angle Θ 3 is 75° to 90°, the emitted light B2 advances in a preferred direction. Since the reflecting surface 6 is composed of the primary reflecting surface 11 and the secondary reflecting surface 12, the light A1 -12-201005227 and B1 which are advanced from the light source toward the inside of the light guiding body in a single direction are reflected even if they are guided. The surface 6 is reflected and becomes light A2 and B2 which advance in two directions. In order to make the light amount of the light A2 and the light B2 have an appropriate ratio, the adjustment can be suitably performed, but the height of the secondary reflecting surface 12 is such that half of the light having a tilt of 15° to 20° can collide with the second reflection. Face 1 2 is preferred. Fig. 5 is a partial cross-sectional view showing the image reading device in which the light beams A2 and B2 are irradiated onto the object 42 to be read. φ As shown in Fig. 4, the lights A2 and B2 reflected by the reflecting surface 6 are emitted to the outside of the light guiding body 1 through the light emitting surface 9, and the reading target 42 shown in Fig. 5 is irradiated. The image reading device is provided with a mounting surface 41 which is formed of a light-transmitting member on the light-emitting surface 9 of the linear light source device, and the reading object 42 in which the image to be taken in is placed is placed. The mounting surface 41 is used. The light emitted from the light exit surface 9 of the light guide 1 is irradiated to the mounting surface 41. In the image reading device, the reading target 42 on which the image to be taken in is placed is placed on the mounting surface 41', and the projection image of the reading object 42 placed on the mounting surface 41 is detected as a reading image. . When a reading object 42 having a thickness such as a book is used, a thickness is generated between the light-irradiating surface of the reading object 42 and the document cover 43. Since the light does not pass through the reading target 42, the light A2 having the angular component inclined in the axial direction X illuminates the end of the reading target 42 without irradiating the original cover 43. However, the light B2 having an angular component inclined in the opposite direction to the axial direction X can be irradiated to a position where the light A2 cannot be irradiated onto the document cover 43, so that the light is not irradiated. Similarly, the case where the reading object 42 has a step of a meander line or the like is also applicable to -13-201005227. Therefore, since the reflecting surface 6 of the groove portion 7 of the embossed groove 5 is constituted by the primary reflecting surface 11 and the secondary reflecting surface 12, it is possible to have two different angular components in the axial direction X from the linear light source device. Since the reading object 42 is emitted, even if the reading object 42 has a thickness or a step, the original cover 43 does not appear, and black streaks do not appear in the read image. φ illustrates a second embodiment of the present invention. Fig. 6 is an enlarged cross-sectional view showing each groove portion 7 of the embossed groove 5 of the light guide of the present invention. In the second embodiment, the linear light source device of the first embodiment is changed in the shape of the groove portion 7 of the embossed groove 5. The groove portion 7a formed with the reflecting surface 6 formed of one surface and the groove portion 7b formed with the reflecting surface 6 composed of the primary reflecting surface 11 and the secondary reflecting surface 12 are alternately formed. The groove portion 7b is a rectangular groove that is immersed in the radial direction Y from the flat surface 8 of the groove portion 7a. The secondary reflecting surface 12 formed in the groove portion 7b has a smaller immersion length in the radial direction Y than the secondary reflecting surface 12 0 of the first embodiment, and the surface area thereof also becomes large. Further, the light transmitting surface 10 formed on the groove portion 7b is also composed of the primary light transmitting surface 13 and the secondary light transmitting surface 14. The angle of inclination 04 of the primary light-transmissive surface 13 is the same as the angle of inclination of the light-transmissive surface 1〇 of the groove portion 7a when the clockwise rotation from the opposite direction of the axial direction X to the primary light-transmissive surface 13 is slightly the same. . The secondary light transmissive surface 14' is formed as a phase opposite to the secondary reflecting surface 12. The inclined angle 05' of the secondary light transmitting surface 14 is a clockwise direction from the opposite direction of the axial direction X up to the secondary light transmitting surface 14. The angle at the time of rotation is larger than the inclination angle 04 of the primary light transmission surface 13. -14 - 201005227 The groove portion 7a is a reflection surface 6 that is immersed in the radial direction γ in the axial direction X, and the continuous reflection surface 6 forms a flat surface 8, and the continuous flat surface 8 forms a light-transmissive surface that protrudes in the opposite direction of the radial direction Υ. 10. In other words, the groove portion 7a sequentially forms the reflecting surface 6, the flat surface 8, and the light transmitting surface 10 in the axial direction X. On the other hand, the groove portion 7b is formed with the primary reflection surface 11 which is immersed in the radial direction γ in the axial direction X, and the secondary reflection surface 11 is formed by the primary reflection surface 11 to continue the secondary reflection surface 12, and the secondary reflection surface 12 is continued to form the flat surface 8 The continuation of the flat surface 8 φ forms the secondary light-transmissive surface 14 that protrudes in the opposite direction to the radial direction Y, and the secondary light-transmissive surface 14 continues to form the primary light-transmissive surface 13 once. In other words, the groove portion 7b sequentially forms the primary reflecting surface 11, the secondary reflecting surface 12, the flat surface 8, the secondary light transmitting surface 14, and the primary light transmitting surface 13 in the axial direction X. The light A1 incident on the reflecting surface 6 of the groove portion 7a is reflected as light A2 having an angle inclined in the axial direction X. On the other hand, the light B1 incident on the primary reflecting surface 11 of the groove portion 7b is made to lengthen the length (height) which is immersed in the radial direction Y of the secondary reflecting surface 12, irrespective of the primary reflecting surface φ 11 . The incident angle or the incident position is substantially reflected again, and is reflected as light B2 having an angle inclined in the opposite direction to the axial direction X. The height of the light A1 incident on the reflecting surface 6 and the contraction of the light B1 incident on the primary reflecting surface 略 are slightly the same, but the reflected light A2, B2 advances in different directions. Further, the light C1 irradiated to the groove portion 7b from the position higher than the light beams A1 and B1 is incident on the secondary reflection surface 12» because the inclination angle of the secondary reflection surface 12 is large, the incident angle of the light C1 is smaller than the critical angle. Light C1 will pass through the secondary reflection surface 12. The transmitted light of the light C1 is again incident from the secondary transmission surface 14 to -15-201005227, and is incident on the inside of the light guide body, and becomes light C2 guided in the axial direction X. In this manner, the groove portion 7a formed with the reflection surface 6 formed of one surface and the groove portion 7b formed with the reflection surface 6 composed of the primary reflection surface 11 and the secondary reflection surface 12 are alternately formed, even from the light source toward the light guide. The light A1 and B1 which are advanced in the single direction in the body are guided, and the light A2 reflected by the reflecting surface 6 of the groove portion 7a and the primary reflecting surface 11 and the secondary reflecting surface 12 of the groove portion 7b can be reflected. The light B2, that is, the light A2, B2 having an angular component having two φ directions in the axial direction X is emitted toward the reading target 42. Further, since the light C1 that has passed through the secondary reflecting surface 12 is again incident on the inside of the light guiding body and becomes the light C2 that is guided in the axial direction X, the light can be efficiently used. Further, the formation interval between the groove portion 7a of the reflection surface 6 formed of one surface and the groove portion 7b formed with the reflection surface 6 composed of the primary reflection surface 11 and the secondary reflection surface 12 may not be formed alternately. The number of the embossed grooves 5 in which the number of the grooves 7b of the reflecting surface 6 including the primary reflecting surface 11 and the secondary reflecting surface 12 is formed by φ is appropriately formed in the formation of the groove portion 7a of the reflecting surface 6 formed of one surface. can. And, on the contrary, it is possible. In the groove portion 7 of the embossed groove 5 on the smooth surface side in the axial direction X of the light guide body, the original cover has the primary reflection surface 11 formed thereon, and the original cover has a shadow on the end portion of the reading target. The groove portion 7b of the reflecting surface 6 formed by the secondary reflecting surface 12 may be used. Description will be given of the third embodiment of the present invention. Fig. 7 is a partially enlarged cross-sectional view showing the groove portion 7 of the embossed groove 5 of the light guide of the present invention. Fig. 7(a) is a view showing a state in which the flat surface 8a of the groove portion 7a is inclined counterclockwise from the axial direction-16-201005227X as shown in Fig. 6, and Fig. 7(b) is a view as shown in Fig. 6 The inclination angle of the secondary reflection surface 12 and the secondary transmission surface 14 of the groove portion 7b is 9 (the case of Γ or less. As shown in Fig. 7(a), the third embodiment is the linear light source device of the second embodiment. The flat surface 8 of the groove portion 7a is formed to be inclined from the axial direction X toward the reverse needle. The flat surface 8 is formed such that the contact with the reflecting surface 6 is slightly rotated counterclockwise as the fulcrum axis direction X. Light A1 When φ is incident on the flat surface 8, the incident angle 0a is smaller than when the flat surface 8 is parallel to the axial direction X. The light A1 is totally reflected by the flat surface 8 at an angle corresponding to the incident angle 0a to become the light A2. The angle 0b of the light A2 with respect to the axial direction X is larger than the case where the flat surface 8 is parallel to the axial direction X, and the light A2 is an angular component which can increase the radial direction Y. As shown in Fig. 7(b), In the embodiment, in the linear light source device of the second embodiment, the inclination angle of the secondary reflection surface 12 and the secondary transmission surface of the groove portion 7b is 90 or less. When the inclination angle of 12 is φ 90° or less, when the light B1 is reflected to the primary reflection surface 11 and is incident on the second reflection surface 12, the angle of incidence 03 with respect to the secondary reflection surface 12 and the inclination angle 03 of the secondary reflection surface 12 are The case of 90° is larger than that of the case of 90°. 2 Since the emission light B2 of the reflection surface 12 corresponds to the incident angle d, the angle 0 e with the radial direction Y becomes small. The light B 2 and the inclination angle 0 3 are 90. In the case of °, since the angular component in the opposite direction to the axial direction X becomes smaller, the angular component in the radial direction Y becomes larger, and therefore the direction is advanced in the direction of the approaching direction Y. The time is from the phase of the phase 14 [Second view] FIG. 1 is a perspective view showing a configuration of a linear light source device according to the present invention. FIG. 2 is an enlarged cross-sectional view showing a linear light source device according to the present invention. [Fig. 3] A projection view in which the light guide of the present invention is cut in the radial direction. [Fig. 4] An enlarged cross-sectional view of each groove portion of the embossed groove of the light guide of the present invention [Fig. 5] A partial cross-sectional view of the image reading device φ for reading the state of the object [Fig. 6] Guide of the present invention Expanded cross-sectional view of each groove portion of the embossed groove of the body [Fig. 7 (a) (b)] A partially enlarged cross-sectional view of the groove portion of the embossed groove of the light guide of the present invention [Fig. 8] Cross-sectional view of the structure of the light source device [Fig. 9] A partial cross-sectional view of the image reading device in which the light is irradiated on the reading target [Description of main components] 1 : Light guide 2: Light source 3: Light take-in portion 4: Smooth surface 5: embossed groove 6: reflecting surface 7: groove portion -18- 201005227 7a: groove portion 7b: groove portion 8: flat surface 9: light exit surface 10: light transmitting surface 1 1 : 1st reflecting surface 1 2 : 2 times Reflecting surface 1 3 : 1st light transmitting surface 14 : 2nd light transmitting surface 4 1 : Mounting surface 42 : Reading target 43 : Original cover 44 : Shadow
-19--19-