200822695 九、發明說明 【發明所屬之技術領域】 本發明係關於照射原稿讀取面以讀取其反射光之圖像 感測器等所使用之線狀照明裝置、圖像感測器及使用此之 畫像讀取裝置。 【先前技術】 以往，在圖像掃描器、傳真機或影印機等畫像讀取裝 置所使用之圖像感測器中，有縮小型、密接型等種類。其 中，密接型圖像感測器（以下稱爲C I S )，係由照明裝置、 等倍成像光學裝置、以及光電轉換元件等所構成。又，該 c I S，一般而言，相較於利用縮小光學系統之圖像感測器 ，由於光路長度較短因此具有機器易於小型化的特徵。因 此容易組裝於機器’而逐漸廣泛使用於薄型之平台畫像讀 取裝置等以取代縮小光學系統。對使用於該c I S之線狀照 明裝置，則要求能以必要以上之照度來照射原稿面，使來 自原稿之反射光具有足夠之光量以到達光電轉換元件。 圖9係習知密接型圖像感測器之構成剖面圖。此處係 表示導光體42爲一支之情形。該密接型圖像感測器具有供 照射原稿之線狀照明裝置，並通過透鏡4 4將來自原稿4 9之 反射光以由光電轉換元件所形成之線感測器4 5接收來轉換 成電氣訊號。 圖9中，4 3係支撐構成構件之構架、44係使原稿之光 學像成像於線感測器4 5上之透鏡陣列、4 5係將具備複數個 200822695 使原稿之光學像光電轉換爲電氣訊號之受光部配置成線狀 的線感測器。又，4 6係裝載有線感測器4 5之感測器基板。 41r，41g，41b係由供照明原稿之發光二極體（以下稱爲 LED)所構成之發光元件41，並配置在往長邊方向延伸之 導光體42的端面。線狀照明裝置具有以取入來自LED之 放射光並使照明光量大致均一地擴及原稿讀取部之1條線 長度之方式設計的導光體42。47係感測器訊號與外部機器 連接之連接器、4 8係支撐原稿4 9之透明玻璃製的原稿支持 台。 一般而言，從配置於導光體42之端面的發光元件所放 射之光，係被導引至丙烯酸製之導光體42中，並在其內部 一邊經複雜之反射一邊從射出面射出至外部以照明原稿49 〇 已使用各種形狀者作爲該種線狀照明裝置，最近亦使 用如圖1 〇所示之角柱形者（專利文獻1)。 圖1 〇係表示習知線狀照明裝置之構成的圖。 該線狀照明裝置10之導光體20，係以***於與LED 光源單元30—體形成之導光體安裝框31之方式構成。此外 ，導光體20於其外側配置有導光體蓋（未圖示）。 專利文獻1:日本特開2005 — 23 6940號公報 【發明內容】 [發明欲解決之課題] 然而，圖10之構成中，LED光源單元30之構成複雜， 200822695 且LED並非一般市售品而是須訂製之LED。又，必須依 導光體之形狀增大導光體安裝框31，隨之必須增大LED 光源單元30之形狀。 本發明之目的在於解決上述習知技術的問題點。 又’本申請案發明之特徵在於提供以相同導光體蓋覆 蓋發光元件與導光體，以使來自發光元件之放射光能高效 率射入於導光體內的線狀照明裝置。 又，亦在於提供使用此線狀照明裝置之圖像感測器、 畫像讀取裝置。 [用以解決課題之手段] 爲達成上述目的，本發明形態之線狀照明裝置具備以 下之構成。亦即，其特徵爲，具有： 發光元件； 長條狀導光體，從端面接受來自前述發光元件所放射 之光，並將所接受之該光導引至長邊方向且將光自射出面 射出；以及 導光體蓋，覆蓋前述導光體且具有供使自前述導光體 之射出面所放射之光通過的開口部，並越過前述導光體之 前述端面以與前述發光元件嵌合。 [發明效果] 根據本發明，具有以下效果。 由於以相同導光體蓋覆蓋發光元件與導光體，因此可 -7- 200822695 使來自發光元件之放射光以高效率射入於導光體。 不須爲防止漏光而考量將導光體嵌插於發光元件側所 產生的複雜構造。 易於進行發光元件與導光體之定位。 【實施方式】 以下，參照附加圖式以詳細說明本發明之最佳實施形 態。此外，以下實施形態並非用來將本發明限於專利申請 之範圍，又，以本實施形態所說明之特徵的所有組合並非 一定爲本發明必要之解決方法。 〔實施形態1〕 圖1係槪略表示本發明之實施形態1之線狀照明裝置 100的立體圖，圖2係沿圖1之I-Ι線的剖面圖。 本實施形態之發光元件1 0 1，係使用市售之白色led ( 日亞化學工業株式會社製之型號：NFSW036B)。該LED 封裝之形狀爲厚度0.8mm、長寬3.5mm。又，該LED係配 置於供散熱之厚度爲2mm的銅製基板102上。 此外’該發光元件（光源）1 0 1，係連接多數個一般亮 度之LED ’由複數個晶片形成亦可。又，亦可使用紅綠藍 之3種L E D以取代白色l E D。 本實施形態中，導光體1 06係將光透過性較高之丙烯 酸樹脂形成爲既定形狀。又，導光體蓋1 〇 3係使用摻練白 色顏料之聚碳酸酯樹脂成型者。該導光體106在使用於〜照 200822695 射A4尺寸原稿之用途時，其長度一般爲230 mm左右。又 ，其剖面形狀爲約30平方mm之扇形（參照圖3)，整體形 狀爲長條棒狀。 103係覆蓋該導光體106之導光體蓋，呈覆蓋至包含發 光元件1 0 1的構成。此處，導光體蓋1 03係覆蓋發光元件 101與導光體10 6間之空氣層104，並具有抵接於構裝發光 元件101之基板102的延長部110，且以包圍發光元件101本 身之方式嵌合。108係來自導光體106之光的射出口，此部 分成爲導光體蓋103的開口部。111係沿導光體106之長邊 方向設置之反射/擴散面，射入於該反射/擴散面1 1 1之光 便被擴散，且其一部分通過與反射/擴散面1 1 1相對向之射 出面107、射出口 108，而照射原稿。105係該導光體106之 受光端面，以該端面105接受從發光元件101所發出之光， 以導引至導光體106之內部。 圖3係本實施形態之導光體1 〇 6的剖面圖，並以相同記 號來表示與前述圖式共通之部分。 圖4係本發明之實施形態1之線狀照明裝置丨〇 〇之發光 元件1 〇 1附近的放大剖面圖。 如圖4所示，本實施形態之線狀照明裝置1 〇 〇中，發光 元件10 1之大小係小於導光體106之剖面。又，延伸至發光 元件101之導光體蓋103，具有覆蓋空氣層1〇4並抵接於構 裝有發光元件101之基板102的延長部110。再者，該導光 體蓋1 0 3係以包圍發光元件1 〇 1之側面（本實施形態中係 LED封裝本身）的方式嵌合。 200822695 從發光元件1 ο 1放射之放射光1 1 2，係由直接到達導光 體106之受光端面105的光線、與因放射角較大而到達導光 體蓋1 03之內側面1 1 3的光線所構成。到達導光體蓋1 03之 內側面1 1 3的光線，在白色聚碳酸酯製之導光體蓋1 03的內 側面1 13反射，或進一步在該導光體蓋103內側面1 13反覆 反射之後，到達導光體106之受光端面105及導光體106。 如上述，以一體覆蓋發光元件101與導光體106之方式形成 導光體蓋103，藉此可使來自發光元件101之放射光高效率 射入於導光體106。 已測量在本實施形態1之線狀照明裝置1 〇〇之射出口 108之長邊方向的照度分布。又，將圖4所示之導光體蓋 103之延長部1 10製作成相當於在先前技術所說明之圖10之 習知線狀照明裝置之導光體安裝框3 1的比較框1 1 5，以作 爲比較例，並設爲圖1 1例示之比較用線狀照明裝置1 1 6。 圖1 1係將本實施形態1之線狀照明裝置設置於圖1 〇所 示之導光體安裝框作爲該比較框之比較用線狀照明裝置之 一部分放大剖面圖。 圖1 1中，比較框1 1 5係使用與實施形態1之導光體蓋 1 0 3相同材質，並從基板1 0 2側加以延長，以呈包圍發光元 件101、空氣層104、及導光體106之受光端面105附近爲止 之框形。此處，導光體蓋103與比較框115係透過邊界117 大致抵接。 以與前述實施形態相同條件測量了該比較用線狀照明 裝置η 6之射出口 1 〇 8的照度分布，並以平均値與實施形態 -10- 200822695 1之照度分布相比較。其結果，可確認本實施形態1之照度 約筒5 %。 又，根據本實施形態1亦具有以下優點。 丙烯酸製之導光體106因吸濕等其長邊方向之長度多 少會膨脹/收縮，並在空氣層104發光元件101與導光體106 之受光端面105的距離會變動。因此，受光端面105能直接 從來自發光元件101之放射光112受光的放射光量會改變， 導光體106能直接受光之光量會變化。 對此，本實施形態1之線狀照明裝置100的構成中，由 於射入光量對導光體1 06幾乎不會變化，因此無法觀察到 從線狀照明裝置1 〇〇射出之光量的變化。 再者，本實施形態1之線狀照明裝置100中，由於延長 至導光體蓋103抵接於基板102的延長部110係呈包圍發光 元件101外形的構造，因此使用於發光元件101之LED可 直接使用市售品。藉此，容易選擇發光元件1 〇 1之零件， 對線狀照明裝置100之製造成本面亦有利。 此外，圖4中雖以直線表示內側面1 1 3之形狀，但亦可 將該內側面η 3設爲以發光元件101之發光點爲焦點之拋物 面形狀。以此方式由於可提高聚光效果並提升來自發光元 件1 0 1之光的利用效率因此非常合適。 〔實施形態2〕 圖5係本發明之實施形態2之線狀照明裝置1 0 0之發光 元件1 〇 1附近的放大剖面圖。該實施形態2中，係表示發光 -11 - 200822695 元件101之尺寸大於導光體106之受光端面105的情形。使 用於本實施形態之發光元件1〇1係LED(日亞化學工業株式 會社製型號：NFSW083)，尺寸爲長寬6.5mmx5.0mm、厚 度爲1.3 5mm。該發光元件101之外形尺寸係大於導光體 106之剖面（受光端面105)。 本實施形態2中，來自發光元件1 〇 1之光線係擴大導光 體蓋1 03之延長部1 1 〇的開口形狀以與圖4同樣地嵌合發光 元件1 0 1。藉此，使來自發光元件1 〇 1之放射光以高效率射 入於導光體106。 又，亦適合以透明樹脂層形成發光元件1 0 1與受光端 面1 05間之區域以取代空氣層1 04。此時之透明樹脂層藉由 適切選擇發光元件1 0 1與受光端面1 0 5之距離或形狀，即可 獲得對導光體1 06之高效率入光。使用於該樹脂層之樹脂 ，係與導光體1 06光學性質相近之例如聚碳酸酯樹脂、丙 烯酸樹脂、或環氧樹脂較爲合適。 本實施形態2之導光體蓋1 03，能易於收容覆蓋以此方 式形成之透明樹脂層。通過該透明樹脂層，可使到達導光 體蓋1 03之內側面1 1 3之來自光源的放射光不會洩漏至外部 而反射/散射，或進一步在該內側面1 1 3反覆反射中入光於 受光端面1 〇 5。 射入於導光體106內之光，在導光體1〇6內反覆全反射 並被導引至導光體106之長邊方向。於該導光體1〇6之一部 分，沿導光體1 〇 6之長邊方向設有反射/擴散面1 1 1。光射 入反射/擴散面η 1時，該射入之光即被擴散，其一部分會 -12- 200822695 通過與反射/擴散面1 1 1相對向之射出面107，而照射原稿 讀取線205 (參照圖6)。 藉由該種構成可形成以高效率利用從發光元件1 0 1放 射之光的線狀照明裝置1 〇〇。 再者，與前述實施形態1同樣地，由於將發光元件1 0 1 設爲嵌合於導光體蓋103之形狀，因此導光體蓋103不會偏 離各發光元件101與導光體106之中心位置，而呈射入於導 光體106之光量不易產生變化的構造。 又，對導光體蓋1 03之內側面η 3藉由無電鍍等進行具 有金屬光澤面之金屬薄膜的表面處理、或塗鍍氧化鈦，由 於可提升來自發光元件1 〇 1之光的反射效率以有效利用放 射光因此係有效。 又，另一種導光體蓋1 03之內側面1 1 3的表面處理，亦 可藉由對成形該導光體蓋103之模具與導光體蓋103之內側 面1 1 3抵接的面進行鏡面加工，以對成形後之導光體蓋1 03 之內側面1 1 3進行鏡面加工。 藉此，可提升在內側面1 1 3之光的反射率，並可使來 自發光元件1 〇 1之放射光以高效率射入於導光體1 〇6。此外 ，以內側面1 1 3整面或僅限於受光端面1 05附近來進行導光 體蓋103之內側面113的表面處理，可考量成本與效果等來 決定。 再者，亦可於導光體蓋103之延長部110之外側以金屬 板設置包覆，以取代對導光體蓋103之內側面113進行表面 處理。藉此，可使通過導光體蓋103但洩漏之光返回導光 -13· 200822695 體蓋103側，並進而使其一部分進入導光體106。 此外，已對上述實施形態1及2均以導光體106—側之 端面爲受光端面，並將發光元件1 0 1配置於該受光端面側 的情形進行了說明。然而，本發明之線狀照明裝置並不限 於該情形。例如，亦可於導光體1 06之另一側端面設置發 光元件，並同樣地亦對該發光元件延長成形製作導光體蓋 亦可。 圖6係槪略表示使用上述線狀照明裝置100之密接型圖 像感測器200的立體圖，圖7係沿圖6之II-II線的剖面圖。 如圖6及圖7所示，該密接型圖像感測器200，係將上 述線狀照明裝置1 〇〇、長軸型透鏡陣列202、以及感測器陣 列基板203收納於箱形構架201而構成。該密接型圖像感測 器2 00，係照明擺置於其上部之玻璃等原稿台（未圖示）上 的原稿，並接收原稿對該照明光之反射光以進行光電轉換 〇 具體而言，密接型圖像感測器200中，線狀照明裝置 1 0 0係以線狀來照明原稿讀取線2 05。以此方式照明之光會 從原稿反射，該讀取位置之光資訊即由長軸型透鏡陣列 2 〇2受光，並成像在配置於感測器陣列基板203之線感測器 2 04上。該線感測器204係將該成像之光轉換成電氣訊號並 輸出，藉此以讀取原稿之構造。 藉由使用該種線狀照明裝置1 〇〇，即可提供能抑制使 用環境所造成之照度特性變化的密接型圖像感測器。 圖8係使用裝載有本發明之實施形態之線狀照明裝置 -14- 200822695 100之密接型圖像感測器200之平台型圖像掃描器（畫像讀 取裝置）300的外觀立體圖。 該畫像讀取裝置3〇〇，係將圖6所示之密接型圖像感測 器2 00收納於筐體301之內部。再者，於該筐體301內設有 供使密接型圖像感測器200移動之驅動馬達3 02及導線303 。又，於該筐體3 〇 1之上面設有玻璃板3 0 4作爲原稿支持體 。又，於該筐體3 0 1之端部安裝有可開閉之供將載置於玻 璃板3 04上之原稿按壓於玻璃板3 04的壓板3 05。 以此方式構成之圖像掃描器中，將原稿以面朝下載置 於玻璃板3 04上並關閉壓板3 05後，驅動驅動馬達3 02並使 導線3 0 3機械性移動。藉此，可使密接型圖像感測器2 0 0往 讀取方向（掃描方向）移動，以讀取原稿畫像。 該密接型圖像感測器200係以一體組裝前述線狀照明 裝置1 0 0之感測器單元而構成。以來自該線狀照明裝置1 〇 〇 之光照射原稿所產生之反射光，藉由密接型圖像感測器 2 00中之長軸型透鏡陣列，聚光於光電轉換元件（線感測器 )，以輸出每條掃描線作爲畫像資訊。該畫像資訊係透過 例如U S B、IE E E 1 3 9 4等介面輸出至所連接之外部機器。 又，或藉由藍芽等無線通訊輸出至外部機器。 以此方式’能提供可讀取片狀原稿之畫像資訊並予以 輸出的圖像掃描器。 如上述使用本實施形態之線狀照明裝置的密接型圖像 感測器或畫像讀取裝置，可得到既不受使用環境影響且穩 定的畫像品質。 -15- 200822695 【圖式簡單說明】 [圖1 ]係槪略表示本發明之實施形態1之線狀照明裝置 100的立體圖。 [圖2]係沿圖1之I-Ι線的剖面圖。 [圖3 ]係本實施形態之線狀照明裝置之導光體的剖面 圖。 [圖4]係本發明之實施形態丨之線狀照明裝置之發光元 件附近的放大剖面圖。 [圖5]係本發明之實施形態2之線狀照明裝置之發光元 件附近的放大剖面圖。 [圖6]係槪略表示使用本實施形態之線狀照明裝置之 密接型圖像感測器的立體圖。 [圖7 ]係沿圖6之11 -11線的剖面圖。 [圖8]係使用裝載有本發明之實施形態之線狀照明裝 置之密接型圖像感測器之平台型圖像掃描器的外觀立體圖 〇 [圖9]係習知密接型圖像感測器之構成剖面圖。 [圖1〇]係表示習知線狀照明裝置之構成的圖。 [圖11 ]係將本實施形態1之線狀照明裝置設置於圖1 〇 所矛:之導光體安裝框作爲該比較框之比較用線狀照明裝置 的一部分放大剖面圖。 【主要元件符號說明】 -16- 200822695 100 :線狀照明裝置 1 〇 1 :發光元件 102 :基板 103 :導光體蓋 104 :空氣層 105 :受光端面（端面） 106 :導光體 1 〇 8 :光射出口 1 1 0 :延長部200822695 IX. The present invention relates to a linear illumination device, an image sensor, and the like for use in an image sensor or the like that illuminates an original reading surface to read reflected light thereof. Image reading device. [Prior Art] In the image sensor used in an image reading device such as an image scanner, a facsimile machine, or a photocopier, there are various types such as a reduced type and an adhesive type. Among them, a close-contact type image sensor (hereinafter referred to as C I S) is composed of an illumination device, a magnification imaging optical device, and a photoelectric conversion element. Further, in general, the IC I has a feature that the machine is easy to be miniaturized because the optical path length is short compared to an image sensor using a reduction optical system. Therefore, it is easy to assemble in a machine', and is gradually used in a thin platform image reading device or the like instead of reducing the optical system. For the linear illumination device used in the cIS, it is required to illuminate the original surface with an illuminance of more than necessary, so that the reflected light from the original has a sufficient amount of light to reach the photoelectric conversion element. Fig. 9 is a cross-sectional view showing the structure of a conventional close-contact type image sensor. Here, the case where the light guide body 42 is one is shown. The close-contact type image sensor has a linear illumination device for illuminating the original, and converts the reflected light from the original 49 by the lens 44 to the line sensor 45 formed by the photoelectric conversion element to be converted into an electric Signal. In Fig. 9, 4 3 is a frame for supporting the constituent members, 44 is a lens array for imaging the optical image of the original on the line sensor 45, and the 45 series will have a plurality of 200822695 for photoelectrically converting the optical image of the original into electrical The light receiving portion of the signal is configured as a line sensor. Further, the 4 6 series is a sensor substrate on which the wired sensor 45 is mounted. 41r, 41g, and 41b are light-emitting elements 41 composed of light-emitting diodes (hereinafter referred to as LEDs) for illuminating the original, and are disposed on the end faces of the light guides 42 extending in the longitudinal direction. The linear illumination device has a light guide body 42 designed to take in the light from the LED and spread the illumination light amount substantially uniformly to the length of one line of the document reading portion. The 47-series sensor signal is connected to an external device. The connector and the 48-piece original support table made of transparent glass that supports the original document 49. Generally, the light emitted from the light-emitting element disposed on the end surface of the light guide body 42 is guided to the light guide body 42 made of acrylic, and is emitted from the exit surface to the inside through the complicated reflection. The externally illuminated original 49 has been used as a linear illumination device, and a prismatic shape as shown in FIG. Fig. 1 is a view showing the configuration of a conventional linear illumination device. The light guide 20 of the linear illumination device 10 is configured to be inserted into the light guide mounting frame 31 formed integrally with the LED light source unit 30. Further, the light guide body 20 is provided with a light guide cover (not shown) on the outer side thereof. [Patent Document 1] Japanese Laid-Open Patent Publication No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. 2005-23-23. SUMMARY OF THE INVENTION [Problem to be Solved by the Invention] However, in the configuration of Fig. 10, the configuration of the LED light source unit 30 is complicated, and 200822695 and the LED is not a general commercial item but LEDs to be ordered. Further, it is necessary to increase the light guide mounting frame 31 in accordance with the shape of the light guide body, and it is necessary to increase the shape of the LED light source unit 30. It is an object of the present invention to solve the above problems of the prior art. Further, the invention of the present application is characterized in that a linear illumination device that covers a light-emitting element and a light guide with the same light guide cover so that the emitted light from the light-emitting element can be efficiently incident into the light guide body is provided. Further, it is also an image sensor and an image reading device that use the linear illumination device. [Means for Solving the Problem] In order to achieve the above object, the linear illumination device of the embodiment of the present invention has the following configuration. That is, it is characterized in that it has: a light-emitting element; a long strip-shaped light guide body that receives light emitted from the light-emitting element from an end surface, and guides the received light to a long-side direction and emits light from the exit surface. And a light guide cover that covers the light guide and has an opening through which light emitted from the light exit surface of the light guide passes, and passes over the end surface of the light guide to be fitted to the light emitting element . [Effect of the Invention] According to the present invention, the following effects are obtained. Since the light-emitting element and the light guide are covered by the same light guide cover, the light emitted from the light-emitting element can be incident on the light guide with high efficiency. It is not necessary to consider the complicated structure in which the light guide body is inserted into the side of the light emitting element in order to prevent light leakage. It is easy to position the light-emitting element and the light guide. [Embodiment] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Further, the following embodiments are not intended to limit the invention to the scope of the patent application, and all combinations of the features described in the embodiments are not necessarily the necessary solutions of the invention. [Embodiment 1] Fig. 1 is a perspective view showing a linear illumination device 100 according to Embodiment 1 of the present invention, and Fig. 2 is a cross-sectional view taken along line I-Ι of Fig. 1. In the light-emitting element 101 of the present embodiment, a commercially available white led (Model: NFS W036B manufactured by Nichia Corporation) is used. The shape of the LED package is 0.8 mm in thickness and 3.5 mm in length and width. Further, the LED was placed on a copper substrate 102 having a thickness of 2 mm for heat dissipation. Further, the light-emitting element (light source) 101 may be formed by connecting a plurality of LEDs having a plurality of general luminances. Further, three kinds of L E D of red, green and blue may be used instead of white l E D . In the present embodiment, the light guide body 106 is formed into a predetermined shape of an acrylic resin having high light transmittance. Further, the light guide cover 1 〇 3 is formed by molding a polycarbonate resin blended with a white pigment. When the light guide body 106 is used for an A4 size original for use in 200822695, the length of the light guide body 106 is generally about 230 mm. Further, the cross-sectional shape is a sector shape of about 30 mm 2 (see Fig. 3), and the overall shape is a long rod shape. The 103 covers the light guide cover of the light guide body 106 and covers the light-emitting element 110. Here, the light guide cover 103 covers the air layer 104 between the light-emitting element 101 and the light guide 106, and has an extension 110 that abuts against the substrate 102 on which the light-emitting element 101 is disposed, and surrounds the light-emitting element 101. It is chiseled in its own way. 108 is an exit port of light from the light guide 106, and this portion serves as an opening of the light guide cover 103. 111 is a reflection/diffusion surface provided along the longitudinal direction of the light guide 106, and light incident on the reflection/diffusion surface 11 1 is diffused, and a part thereof passes through the reflection/diffusion surface 11 1 The injection surface 107 and the ejection opening 108 are irradiated to the original. 105 is a light-receiving end surface of the light guide body 106, and the light emitted from the light-emitting element 101 is received by the end surface 105 to be guided to the inside of the light guide body 106. Fig. 3 is a cross-sectional view of the light guide body 〇 6 of the present embodiment, and the same reference numerals are used to show the same portions as the above-mentioned drawings. Fig. 4 is an enlarged cross-sectional view showing the vicinity of the light-emitting element 1 〇 1 of the linear illumination device according to the first embodiment of the present invention. As shown in Fig. 4, in the linear illumination device 1 of the present embodiment, the size of the light-emitting element 10 1 is smaller than the cross section of the light guide 106. Further, the light guide cover 103 extending to the light-emitting element 101 has an extension portion 110 which covers the air layer 1〇4 and abuts against the substrate 102 on which the light-emitting element 101 is mounted. Further, the light guide cover 203 is fitted so as to surround the side surface of the light-emitting element 1 〇 1 (in the present embodiment, the LED package itself). 200822695 The radiation 1 1 2 radiated from the light-emitting element 1 ο 1 is the light that reaches the light-receiving end surface 105 of the light guide 106 directly, and reaches the inner side surface 1 1 3 of the light guide cover 103 due to the large radiation angle. Made up of light. The light reaching the inner side surface 113 of the light guide cover 103 is reflected on the inner side surface 13 of the white polycarbonate light guide cover 103, or further on the inner side surface 13 of the light guide cover 103. After the reflection, the light receiving end surface 105 of the light guide body 106 and the light guide body 106 are reached. As described above, the light guide cover 103 is formed so as to integrally cover the light-emitting element 101 and the light guide 106, whereby the emitted light from the light-emitting element 101 can be efficiently incident on the light guide 106. The illuminance distribution in the longitudinal direction of the ejection opening 108 of the linear illumination device 1 of the first embodiment has been measured. Further, the extension portion 110 of the light guide cover 103 shown in Fig. 4 is formed as a comparison frame 11 corresponding to the light guide mounting frame 31 of the conventional linear illumination device of Fig. 10 described in the prior art. 5, as a comparative example, the comparative linear illumination device 1 16 illustrated in Fig. 11 is used. Fig. 1 is an enlarged cross-sectional view showing a portion of the linear illumination device in which the linear illumination device of the first embodiment is placed on the light guide mounting frame shown in Fig. 1 as a comparison frame. In Fig. 11, the comparison frame 1 1 5 is made of the same material as the light guide cover 10 3 of the first embodiment, and is extended from the substrate 10 side to surround the light-emitting element 101, the air layer 104, and the guide. The frame shape of the light body 106 near the light receiving end surface 105 is formed. Here, the light guide cover 103 and the comparison frame 115 are substantially in contact with each other through the boundary 117. The illuminance distribution of the exit port 1 〇 8 of the comparative linear illumination device η 6 was measured under the same conditions as the above-described embodiment, and compared with the average 値 and the illuminance distribution of the embodiment -10- 200822695 1 . As a result, it was confirmed that the illuminance of the first embodiment was about 5%. Further, according to the first embodiment, the following advantages are also obtained. The light guide body made of acrylic acid 106 expands/contracts in length in the longitudinal direction due to moisture absorption, and the distance between the light-emitting element 101 of the air layer 104 and the light-receiving end surface 105 of the light guide body 106 fluctuates. Therefore, the amount of light that the light receiving end face 105 can receive directly from the emitted light 112 from the light emitting element 101 changes, and the amount of light that the light guiding body 106 can directly receive light changes. On the other hand, in the configuration of the linear illumination device 100 of the first embodiment, since the amount of incident light hardly changes to the light guide body 106, the change in the amount of light emitted from the linear illumination device 1 cannot be observed. Further, in the linear illumination device 100 of the first embodiment, the extension portion 110 that is extended to the light guide cap 103 abutting on the substrate 102 has a structure that surrounds the outer shape of the light-emitting element 101, and therefore is used for the LED of the light-emitting element 101. Commercial products can be used directly. Thereby, it is easy to select the components of the light-emitting element 1 〇 1 and it is also advantageous for the manufacturing cost of the linear illumination device 100. Further, although the shape of the inner side surface 1 1 3 is shown by a straight line in Fig. 4, the inner side surface η 3 may be a paraboloid shape having a focus of the light-emitting element 101 as a light-emitting point. In this way, it is very suitable because it can improve the light collecting effect and improve the utilization efficiency of light from the light-emitting element 101. [Embodiment 2] Fig. 5 is an enlarged cross-sectional view showing the vicinity of a light-emitting element 1 〇 1 of a linear illumination device 100 according to a second embodiment of the present invention. In the second embodiment, the case where the size of the light-emitting -11 - 200822695 element 101 is larger than the light-receiving end surface 105 of the light guide body 106 is shown. The light-emitting element 1〇1 LED (Model: NFSW083, manufactured by Nichia Chemical Industry Co., Ltd.) of the present embodiment has a length of 6.5 mm x 5.0 mm and a thickness of 1.35 mm. The outer shape of the light-emitting element 101 is larger than the cross section of the light guide body 106 (light-receiving end surface 105). In the second embodiment, the light from the light-emitting element 1 〇 1 expands the opening shape of the extension portion 1 1 导 of the light guide cover 103, and the light-emitting element 110 is fitted in the same manner as in Fig. 4 . Thereby, the emitted light from the light-emitting element 1 〇 1 is incident on the light guide 106 with high efficiency. Further, it is also suitable to form a region between the light-emitting element 10 1 and the light-receiving end surface 156 with a transparent resin layer instead of the air layer 104. At this time, the transparent resin layer can obtain high-efficiency light input to the light guide body 106 by appropriately selecting the distance or shape of the light-emitting element 10 1 and the light-receiving end face 1 0 5 . The resin used for the resin layer is preferably a polycarbonate resin, an acrylic resin, or an epoxy resin similar to the optical property of the light guide 106. The light guide cover 203 of the second embodiment can easily accommodate and cover the transparent resin layer formed in this manner. With the transparent resin layer, the emitted light from the light source that reaches the inner side surface 1 1 3 of the light guide cover 103 can be reflected/scattered without leaking to the outside, or further reflected in the inner side surface 1 1 3 Light on the light receiving end face 1 〇5. The light incident on the light guide body 106 is totally totally reflected in the light guide body 1〇6 and guided to the longitudinal direction of the light guide body 106. A reflection/diffusion surface 11 is provided along a longitudinal direction of the light guide body 1 之一 6 in a part of the light guide body 〇6. When the light is incident on the reflection/diffusion surface η 1 , the incident light is diffused, and a part thereof -12-200822695 passes through the exit surface 107 opposite to the reflection/diffusion surface 1 1 1 to illuminate the original reading line 205. (Refer to Figure 6). With this configuration, the linear illumination device 1 利用 which utilizes the light emitted from the light-emitting element 110 can be formed with high efficiency. Further, in the same manner as in the first embodiment, since the light-emitting element 10 1 is formed in the shape of the light guide cover 103, the light guide cover 103 does not deviate from the light-emitting element 101 and the light guide 106. The center position is a structure in which the amount of light incident on the light guide body 106 is less likely to change. Further, the inner surface η 3 of the light guide cover 203 is subjected to surface treatment of a metal thin film having a metallic luster surface by electroless plating or plating of titanium oxide, thereby enhancing reflection of light from the light-emitting element 1 〇1. Efficiency is effective in effectively utilizing the emitted light. Further, the surface treatment of the inner side surface 113 of the other light guide cover 103 may be performed by a surface in which the mold for forming the light guide cover 103 and the inner surface 1 1 3 of the light guide cover 103 are in contact with each other. Mirror processing is performed to mirror-finish the inner side surface 1 1 3 of the formed light guide cover 103. Thereby, the reflectance of the light on the inner side surface 1 13 can be increased, and the emitted light from the light-emitting element 1 〇 1 can be incident on the light guide body 1 〇 6 with high efficiency. Further, the surface treatment of the inner side surface 113 of the light guide cover 103 by the entire inner side surface 1 1 3 or only in the vicinity of the light receiving end surface 105 can be determined in consideration of cost, effect, and the like. Further, instead of surface-treating the inner side surface 113 of the light guide cover 103, the outer surface of the extension portion 110 of the light guide cover 103 may be covered with a metal plate. Thereby, the light leaking through the light guide cover 103 can be returned to the side of the body cover 103 of the light guide -13. 200822695, and a part thereof can be further introduced into the light guide body 106. Further, in the above-described first and second embodiments, the end surface on the side of the light guide 106 is the light receiving end surface, and the light emitting element 110 is disposed on the light receiving end side. However, the linear illumination device of the present invention is not limited to this case. For example, a light-emitting element may be provided on the other end surface of the light guide body 106, and the light guide member may be formed by extending the light-emitting element in the same manner. Fig. 6 is a perspective view schematically showing a close-contact type image sensor 200 using the above-described linear illumination device 100, and Fig. 7 is a cross-sectional view taken along line II-II of Fig. 6. As shown in FIG. 6 and FIG. 7 , the close-contact image sensor 200 houses the linear illumination device 1 〇〇, the long-axis lens array 202 , and the sensor array substrate 203 in a box frame 201 . And constitute. The close-contact type image sensor 200 is configured to illuminate an original placed on a document table (not shown) such as glass on the upper portion thereof, and receive the reflected light of the original light on the illumination light for photoelectric conversion, specifically In the close-contact type image sensor 200, the linear illumination device 100 illuminates the original reading line 205 in a line shape. The light illuminating in this manner is reflected from the original, and the light information of the reading position is received by the long-axis lens array 2 〇 2 and imaged on the line sensor 208 disposed on the sensor array substrate 203. The line sensor 204 converts the imaged light into an electrical signal and outputs it, thereby reading the configuration of the original. By using such a linear illumination device 1, it is possible to provide a close-contact type image sensor capable of suppressing variations in illuminance characteristics caused by the use environment. Fig. 8 is an external perspective view of a platform type image scanner (image reading device) 300 using the close-contact type image sensor 200 of the linear illumination device -14-200822695 100 of the embodiment of the present invention. In the image reading device 3, the close-contact type image sensor 200 shown in Fig. 6 is housed inside the casing 301. Further, a drive motor 312 and a lead wire 303 for moving the close-contact type image sensor 200 are provided in the casing 301. Further, a glass plate 340 is provided on the upper surface of the casing 3 〇 1 as a document support. Further, an end plate of the casing 301 is attached with a press plate 305 which can be opened and closed to press the original placed on the glass plate 384 against the glass plate 34. In the image scanner constructed in this manner, after the original is placed face-to-face on the glass plate 308 and the platen 305 is closed, the drive motor 312 is driven to mechanically move the wire 303. Thereby, the close-contact type image sensor 200 can be moved in the reading direction (scanning direction) to read the original image. The close-contact type image sensor 200 is configured by integrally assembling the sensor unit of the linear illumination device 100. The reflected light generated by the illumination from the original of the linear illumination device 1 is condensed on the photoelectric conversion element (line sensor) by the long-axis lens array in the close-contact type image sensor 200 ), to output each scan line as portrait information. The image information is output to the connected external device through interfaces such as U S B and IE E E 1 3 9 4 . Or, it can be output to an external device by wireless communication such as Bluetooth. In this way, an image scanner capable of reading image information of a sheet-shaped original and outputting it can be provided. As described above, the close-contact type image sensor or the image reading device using the linear illumination device of the present embodiment can obtain image quality that is not affected by the use environment and is stable. -15-200822695 [Brief Description of the Drawings] Fig. 1 is a perspective view showing a linear lighting device 100 according to the first embodiment of the present invention. Fig. 2 is a cross-sectional view taken along line I-Ι of Fig. 1. Fig. 3 is a cross-sectional view showing a light guide of the linear illumination device of the embodiment. Fig. 4 is an enlarged cross-sectional view showing the vicinity of a light-emitting element of a linear illumination device according to an embodiment of the present invention. Fig. 5 is an enlarged cross-sectional view showing the vicinity of a light-emitting element of the linear illumination device according to the second embodiment of the present invention. Fig. 6 is a perspective view showing a close-contact type image sensor using the linear illumination device of the embodiment. [Fig. 7] is a cross-sectional view taken along line 11-11 of Fig. 6. 8 is an external perspective view of a platform type image scanner using a close-contact type image sensor equipped with a linear illumination device according to an embodiment of the present invention. [FIG. 9] is a conventional close-contact type image sensing. A cross-sectional view of the structure of the device. 1A is a view showing a configuration of a conventional linear illumination device. Fig. 11 is a partially enlarged cross-sectional view showing the linear illumination device of the first embodiment in which the light guide mounting frame of Fig. 1 is used as a comparative comparative linear illumination device. [Description of main component symbols] -16- 200822695 100 : Linear illumination device 1 〇1 : Light-emitting element 102 : Substrate 103 : Light guide cover 104 : Air layer 105 : Light-receiving end face (end face) 106 : Light guide 1 〇 8 : Light exit 1 1 0 : Extension