1339294 九、發明說明： 【發明所屬之技術領域】 本發明係關於一種背光模組，特別係關於一種直下式背光模組。 【先前技術】 近年來，液晶顯示器由於其輕、薄、小與耗電低等特點，得到了廣 泛應用。由於液晶本身不具備發光特性，因此需背光模組為其提供背光 源，以實現液晶之顯示功能。 背光模組分為侧光式與直下式兩種。對於中小尺寸之液晶顯示器， 侧光式背光模組具有輕、薄及耗電低等優點。.然而，隨著科技之發展， 對大尺寸液晶顯示器之需求日趨增多，而側光式背光模組難以滿足大尺 寸液晶顯示器之亮度要求’因而直下式背光模組迅速發展起來。 一般直下式背光模組均於一密閉空間内之底面採用了複數光源，光 源於作業時產生大量之熱易造成累積，從而導致光源壽命及擴散片變形 等問題，影響背光模組發光之均勻性及亮度，因而背光模組需設置散熱 機構，以降低其内部溫度。 請參閱第一圖’其係先前技術之直下式背光模組。該直下式背光模 組100包括一腔體110、一擴散片120、一反射板130及複數光源150。 該反射板130設置於該腔體110底部’其用於將光源產生之光線向 上反射以增加光之使用率。該擴散片120係將光進一步均勻分散，該腔 體110係將該擴散片120'反射板130及複數光源15〇收容並使之與外界 隔絕，防止灰塵進入。為了散熱之需要，該直下式背光模組1〇〇常常還 包括一設置於底部之複數散熱鰭片111，而該散熱鰭片1U通常導致背光 模組100之厚度增加。 【發明内容】 有鑒於此’有必要提供一種厚度薄且可有效散熱之直下式背光模組。 一種直下式背光模組，其包括：一擴散片；至少一設置於該擴散片 側邊下方之光源固定座，該光源固定座包括一設置於其内表面之光源固 定面及複數設置於其外表面之散熱鰭片；至少一設置於該光源固定面之 5 1339294 光源，以及一反射板’其一端設置於該光源固定座底部並且其另一端向 該擴散片f曲延伸，且該反射板具有—朝向該光源及擴散片之反射面。 相較於先前技術，具有散熱鰭片及光源固定面之光源固定座設置於 該擴散片側邊下方’光源設置於該光源固定面以提供光線，複數散熱鰭 片設置於該光源固定座外表面，有效避免了因為散熱鰭片及光源設置於 擴散片之正下方而造成背光模組厚度增加。同時，光源產生之熱量藉由 光源固定座及散熱鰭片傳出’大幅降低了背光模組之工作溫度。並且， 該反射板及光源反射罩可有效提高該背光模組之光利用率。 【實施方式】 下面將結合附圖及多個實施例對本發明之直下式背光模組作進一步 詳細說明。 請一並參閱第二圖、第三圖及第四圖，本發明第一實施例提供之直 下式背光模組200包括：一擴散片210、至少一光源固定座220、複數光 源230及一反射板240。 該光源固定座220呈一長條狀，其設置於該擴散片210側邊下方。 該光源固定座220包括一設置於其内表面之光源固定面221及複數設置 於其外表面之散熱鰭片225。該光源230設置於該光源固定座220之光源 固定面221。該反射板240 —端設置於該光源固定座220之底部，另一端 向所述擴散片210彎曲延伸，形成一朝向該光源230及擴散片210之反 射面241 ’該灰射板240之反射面241爲一孤形曲面。 該光源固定座220係採用具有高導熱性能之金屬材料製成，本實施 例可優選鋁合金、鎂合金或銅合金製成》該光源230可包括發光二極體、 冷陰極燈管及外部電極螢光燈管。 該反射板240可透過金屬板拋光或貼附金屬薄膜製得，亦可透過真 空沉積一金屬或合金反射層製得，其主要作用係將該光源230所發出之 部份光線反射至該擴散片210以提高光利用率。 該擴散片210相對該反射板240之部位設置有複數散射結構，該散 射結構可將源自光源230及反射板240之光線加以擴散，以提高該背光 6 1339294 模組200之發光均勻性及亮度。 該光源230於工作時同時發出光與熱。該光源230所發出光之一部 分直接經由該擴散片210並發散出去，另一部分到達該反射板240之反 射面241上，經由其反射後透過該擴散片210並發散出去。該光源230 所發出之熱主要藉由該散熱鰭片225散發出去。 可以理解，為增加該背光模組200之散熱性能，可於該光源固定座 220與該光源230之間進一步設置一導熱介質層26〇.，該導熱介質層26〇 係一具有導熱功能之導熱片或導熱膏。 另外，該背光模組200可進一步包括一具有散熱功能之鋁基電路板 270 ’該鋁基電路板27〇設置於該光源23〇與該導熱介質層26〇之間以增 加該光源230之組裝方便性。 此外，該背光模組200還可包括一殼體280，該殼體280為一方形框 架，其包括一底面281及一端與該底面281相連之三側面283，該三側面 283之另一端形成一開口 285 ’且其中相對兩側面283及底面281形成一 側開口 287。所述光源固定座220置於該殼體280靠近側開口 287之底面 28卜該殼體280之大小與該擴散片210相配，該擴散片210可設置於該 殼體280之開口 285處。該殼體280可收容並固定該光源固定座220、複 數光源230及反射板240 » 清參閱第五圖’本發明第二實施例與本發明之第一實施例相似，其 不同在於：該光源固定座320之光源固定面321與該反射板340之水平 底面形成一夾角，該夾角6>,為60度。本實施例中之鋁基電路板370 係一可選元件。 凊參閱第六圖’本發明第三實施例與本發明之第二實施例相似，其 不同在於：該光源固定座420之光源固定面421與該反射板440之水平 底面所形成夹角02為丨20度。 由本發明第一實施例、第二實施例及第三實施例不難看出，為增加 該背光模組結構設計之便利性及發光之均勻性，該光源固定座之光源固 定面與該反射板之水平底面可形成一夹角，該夾角之優選取值範圍為30 至150度。 7 1339294 為增加背光模組之光利用率，本發明亦可於背光模組之光源固定面 上设置反射部，請參閱第七圖，本發明第四實施例與本發明之第三實施 例相似，其不同在於：該背光模組5〇〇之光源固定座52〇之光源固定面 521之上端延伸形成有一上反射部5211，該上反射部5211靠近該光源53〇 一側具有一朝向該反射板540之上反射面5213。該光源固定面521之下 端延伸形成有朝向該擴散片510之下反射部5215,該下反射部5215具有 一朝向該擴散片510之下反射面5217，該下反射面52Π與該上反射面 5213相對並與該反射面541相連。該上反射部5211可將該光源530向上 發出之部分光綫反射至反射板540之反射面541，再經底其反射後進入該 擴散片510以增加發光均勻性，該下反射部5215可將該光源530向下發 出之部分光綫反射至擴散片51〇以增加光利用率 當然，為增加背光模組之光利用率，本發明亦可於背光模組之光源 固疋面上設置光源反射罩，請參閱第八圖，本發明第五實施例與本發明 之第二貫施例相似，其不同在於：該背光模組還包括一光源反射罩 680 ’該光源反射罩680設置於該光源固定座62〇與該光源630之間，其 具有一朝向該光源630之反射面68卜該反射面681可將光源63〇所發部 份光反射至反射板640及擴散片610。 為增加背光模組之發光功率，本發明亦可於背光模組中設置一與所 述光源固疋座相對之第二光源固定座，請參閱第九圖，本發明第六實施 例與本發明之第四實施例相似，其不同在於：該背光模組還包括— 第二光源固定座723及設置於該第二光源固定座723上之複數光源7犯。 該第二光源固定座723與所述光賴定座721具有相同結構，該第二光 源固定座723之光源固定面7231與所述光源固定座721之光源固定面 7211相對設置^>該反射板74〇設置於該兩光源固定座之間。該反射板74〇 具有-長條形凸起742 ’該凸起742之長度方向與該兩光源固定座721 及723相平行，且該凸起742兩側之反射面741及了奶分別朝向該兩光 源固定座之光源731及733。可以理解，該背光模組糊還可包括一殼體 780，該殼體780為-方形框架，其包括一底面781及一端與該底面781 相連之兩相對側面（圖未標），該兩相對側面之另—端形成_開口（圖未 8 1339294 標），且該兩相對側面及底面781形成兩側開口（圖未標）。所述光源固 定座了21及第二光源固定座723分別設置於靠近該兩側開口之底面781。 該殼體780之大小與該擴散片710相配，該擴散片710可設置於該殼體 780之開口處。該殼體780可收容並固定所述光源固定座721與固定於其 上之光源731、第二光源固定座723與固定於其上之光源733以及反射板 740。 本發明之直下式背光模組，具有散熱鰭片及光源固定面之光源固定 座設置於該擴散片側邊下方，光源設置於該光源固定面以提供光線，複 數散熱鰭片設置於該光源固定座外表面，有效避免了因為散熱鰭片及光 源設置於擴散片之正下方而造成背光模組厚度增加。同時，光源產生之 熱量藉由光源固定座及散熱鰭片傳出，大幅降低了背光模組之工作溫 度。並且，該反射板及光源反射罩可有效提高該背光模組之光利用率。 綜上所述，本發明符合發明專利要件，爰依法提出專利申請。惟， 以上所述者僅為本發明之較佳實施例，舉凡熟悉本案技藝之人士，在爰 依本發明精神所作之等效修飾或變化，皆應涵蓋於以下之申請專利範圍 内。 【圖式簡要說明】 第一圖係先前技術之直下式背光模組截面示意圖； 第二圖係本發明第-實施例之直下式背光模之組件示意圖； 第三圖係第二騎示之直下式背紐組之組裝示意圖； 第四圖係第三圖所示之直下式絲模組沿IV_IV線之截面示意圖； 第五圖係本發明第二實施例之直下式背光模組截面示意圖； 第/、圖係本發明第三實施例之直下式背光模喊面示意圖； 第七圖係本發明第四實施例之直下式背光模組截面示意圖； 第八圖係本發明第五實施例之直下式背光模組戴面示意圖； 第九圖係本發明第六實施例之直下式背光模組截面示意圖。 【主要元件符號說明】 9 1339294 擴散片 210 、 510 、 610 ' 710 光源固定座 220、320、420、520、620、721、723 光源固定面 221 ' 321 ' 421 ' 521 ' 7211 ' 7231 散熱鰭片 225 反射部 5211 ' 5215 反射面 241、5213、5217、541、681、741、745 光源 230、530、630、731、733 反射板 240、340、440、540、640、740 凸起 742 導熱介質層 260 鋁基電路板 270 、 370 殼體 280 ' 780 底面 281 、 781 側面 283 開口 285 侧開口 287 光源反射罩 680 夹角 Θ、、Θ1 101339294 IX. Description of the Invention: [Technical Field] The present invention relates to a backlight module, and more particularly to a direct type backlight module. [Prior Art] In recent years, liquid crystal displays have been widely used due to their characteristics of being light, thin, small, and low in power consumption. Since the liquid crystal itself does not have the illuminating property, the backlight module is required to provide a backlight for the liquid crystal display function. The backlight module is divided into two types: side light type and direct type. For small and medium size LCD monitors, the edge-lit backlight module has the advantages of lightness, thinness and low power consumption. However, with the development of technology, the demand for large-size liquid crystal displays is increasing, and the edge-lit backlight modules are difficult to meet the brightness requirements of large-size liquid crystal displays. Thus, the direct-lit backlight modules have rapidly developed. Generally, the direct type backlight module adopts a plurality of light sources on the bottom surface of a sealed space, and the light source generates a large amount of heat during operation, which is easy to accumulate, thereby causing problems such as the life of the light source and the deformation of the diffusion sheet, and affecting the uniformity of illumination of the backlight module. And brightness, so the backlight module needs to be equipped with a heat dissipation mechanism to reduce its internal temperature. Please refer to the first figure, which is a direct-lit backlight module of the prior art. The direct type backlight module 100 includes a cavity 110, a diffusion sheet 120, a reflection plate 130, and a plurality of light sources 150. The reflector 130 is disposed at the bottom of the cavity 110. It is used to reflect the light generated by the light source to increase the usage rate of light. The diffusion sheet 120 further uniformly disperses light, and the cavity 110 accommodates the diffusion sheet 120' reflection plate 130 and the plurality of light sources 15A to prevent it from entering the outside. For the purpose of heat dissipation, the direct-type backlight module 1 often includes a plurality of heat-dissipating fins 111 disposed at the bottom, and the heat-dissipating fins 1U generally cause an increase in the thickness of the backlight module 100. SUMMARY OF THE INVENTION In view of the above, it is necessary to provide a direct type backlight module which is thin and can effectively dissipate heat. A direct type backlight module includes: a diffusion sheet; at least one light source fixing seat disposed under the side of the diffusion sheet, the light source fixing base includes a light source fixing surface disposed on the inner surface thereof and a plurality of outer surface disposed outside the light source fixing base a heat dissipating fin of the surface; at least one light source disposed on the fixing surface of the light source; and a reflecting plate having one end disposed at the bottom of the light source fixing seat and the other end of which extends to the diffusion piece f, and the reflecting plate has - a reflecting surface facing the light source and the diffusion sheet. Compared with the prior art, a light source fixing seat having a heat dissipating fin and a light source fixing surface is disposed under the side of the diffusing sheet. The light source is disposed on the light source fixing surface to provide light, and the plurality of heat dissipating fins are disposed on the outer surface of the light source fixing seat. The effective avoidance of the thickness of the backlight module is caused by the fins and the light source being disposed directly under the diffusion sheet. At the same time, the heat generated by the light source is transmitted by the light source fixing seat and the heat dissipation fins to greatly reduce the operating temperature of the backlight module. Moreover, the reflector and the light source reflector can effectively improve the light utilization efficiency of the backlight module. [Embodiment] Hereinafter, a direct type backlight module of the present invention will be further described in detail with reference to the accompanying drawings and embodiments. Referring to the second, third, and fourth figures, the direct-lit backlight module 200 of the first embodiment of the present invention includes: a diffusion sheet 210, at least one light source holder 220, a plurality of light sources 230, and a reflection. Board 240. The light source fixing base 220 has an elongated shape and is disposed below the side of the diffusion sheet 210. The light source holder 220 includes a light source fixing surface 221 disposed on an inner surface thereof and a plurality of heat dissipation fins 225 disposed on an outer surface thereof. The light source 230 is disposed on the light source fixing surface 221 of the light source fixing base 220. The reflector 240 is disposed at the bottom of the light source holder 220, and the other end is bent and extended toward the diffusion sheet 210 to form a reflective surface 241 of the light source 230 and the diffusion sheet 210. 241 is an orphaned surface. The light source fixing base 220 is made of a metal material having high thermal conductivity. The embodiment may be preferably made of an aluminum alloy, a magnesium alloy or a copper alloy. The light source 230 may include a light emitting diode, a cold cathode fluorescent tube and an external electrode. Fluorescent tube. The reflector 240 can be made by polishing or attaching a metal film through a metal plate, or can be formed by vacuum depositing a metal or alloy reflective layer, and its main function is to reflect part of the light emitted by the light source 230 to the diffusion sheet. 210 to improve light utilization. A diffusing structure is disposed on the portion of the diffuser 210 opposite to the reflector 240. The diffusing structure diffuses light from the light source 230 and the reflector 240 to improve the uniformity and brightness of the backlight of the backlight module 1 1339294. . The light source 230 emits light and heat simultaneously during operation. A part of the light emitted from the light source 230 is directly diffused through the diffusion sheet 210, and the other portion reaches the reflection surface 241 of the reflection plate 240, is reflected by the diffusion sheet 210, and is diffused through the diffusion sheet 210. The heat emitted by the light source 230 is mainly emitted by the heat dissipation fins 225. It can be understood that, in order to increase the heat dissipation performance of the backlight module 200, a heat conducting medium layer 26 is further disposed between the light source fixing base 220 and the light source 230. The heat conducting medium layer 26 is a heat conducting function having a heat conducting function. Sheet or thermal paste. In addition, the backlight module 200 can further include an aluminum-based circuit board 270 having a heat dissipation function. The aluminum-based circuit board 27 is disposed between the light source 23 and the heat conductive medium layer 26 to increase the assembly of the light source 230. Convenience. In addition, the backlight module 200 can further include a housing 280. The housing 280 is a square frame including a bottom surface 281 and three sides 283 connected to the bottom surface 281 at one end. The other end of the three sides 283 form a square. The opening 285' and the opposite side 283 and the bottom surface 281 form a side opening 287. The light source holder 220 is disposed on the bottom surface 28 of the housing 280 adjacent to the side opening 287. The housing 280 is sized to match the diffusion sheet 210. The diffusion sheet 210 can be disposed at the opening 285 of the housing 280. The housing 280 can receive and fix the light source fixing base 220, the plurality of light sources 230 and the reflecting plate 240. Referring to the fifth figure, the second embodiment of the present invention is similar to the first embodiment of the present invention, and the difference is that the light source The light source fixing surface 321 of the fixing base 320 forms an angle with the horizontal bottom surface of the reflecting plate 340, and the angle 6> is 60 degrees. The aluminum-based circuit board 370 in this embodiment is an optional component. Referring to the sixth figure, the third embodiment of the present invention is similar to the second embodiment of the present invention, except that the angle between the light source fixing surface 421 of the light source fixing base 420 and the horizontal bottom surface of the reflecting plate 440 is丨 20 degrees. According to the first embodiment, the second embodiment, and the third embodiment of the present invention, in order to increase the convenience of the design of the backlight module and the uniformity of illumination, the light source fixing surface of the light source fixing seat and the reflecting plate are The horizontal bottom surface may form an included angle, and the angle preferably ranges from 30 to 150 degrees. 7 1339294 In order to increase the light utilization efficiency of the backlight module, the present invention can also provide a reflecting portion on the light source fixing surface of the backlight module. Referring to the seventh figure, the fourth embodiment of the present invention is similar to the third embodiment of the present invention. The difference is that the upper end of the light source fixing surface 521 of the light source fixing base 52 of the backlight module 5 extends to form an upper reflecting portion 5211, and the upper reflecting portion 5211 has a side facing the light source 53 朝向 facing the reflection. A reflective surface 5213 is above the plate 540. The lower end of the light source fixing surface 521 is formed with a reflecting portion 5215 facing the diffuser 510. The lower reflecting portion 5215 has a reflecting surface 5217 facing the diffuser 510. The lower reflecting surface 52 Π and the upper reflecting surface 5213 It is opposite to and connected to the reflecting surface 541. The upper reflecting portion 5211 can reflect a part of the light emitted from the light source 530 to the reflecting surface 541 of the reflecting plate 540, and then enter the diffusing sheet 510 through the bottom to increase the uniformity of the light, and the lower reflecting portion 5215 can The light emitted from the light source 530 is reflected to the diffusion sheet 51 to increase the light utilization efficiency. Of course, in order to increase the light utilization efficiency of the backlight module, the present invention can also provide a light source reflection on the light source solid surface of the backlight module. Referring to the eighth embodiment, the fifth embodiment of the present invention is similar to the second embodiment of the present invention. The difference is that the backlight module further includes a light source reflector 680. The light source reflector 680 is disposed on the light source. Between the fixing base 62〇 and the light source 630, there is a reflecting surface 68 facing the light source 630. The reflecting surface 681 reflects the light emitted by the light source 63〇 to the reflecting plate 640 and the diffusion sheet 610. In order to increase the illuminating power of the backlight module, the present invention can also provide a second light source fixing base opposite to the light source fixing base in the backlight module. Referring to the ninth embodiment, the sixth embodiment of the present invention and the present invention The fourth embodiment is similar in that the backlight module further includes a second light source fixing base 723 and a plurality of light sources 7 disposed on the second light source fixing base 723. The second light source fixing base 723 has the same structure as the light source fixing seat 721, and the light source fixing surface 7231 of the second light source fixing base 723 is opposite to the light source fixing surface 7211 of the light source fixing base 721. The plate 74 is disposed between the two light source fixing seats. The reflector 74 has a long strip-shaped protrusion 742'. The length of the protrusion 742 is parallel to the two light source holders 721 and 723, and the reflective surface 741 and the milk on both sides of the protrusion 742 face the same The light sources 731 and 733 of the two light source fixing seats. It can be understood that the backlight module paste can further include a housing 780, which is a square frame, and includes a bottom surface 781 and two opposite sides (not labeled) connected to the bottom surface 781 at one end. The other end of the side forms an opening (not shown in Fig. 8 1339294), and the two opposite sides and the bottom surface 781 form openings on both sides (not shown). The light source fixing seat 21 and the second light source fixing seat 723 are respectively disposed on the bottom surface 781 of the two side openings. The housing 780 is sized to match the diffuser 710, and the diffuser 710 can be disposed at the opening of the housing 780. The housing 780 can house and fix the light source holder 721 and the light source 731, the second light source holder 723, and the light source 733 and the reflection plate 740 fixed thereto. In the direct type backlight module of the present invention, a light source fixing seat having a heat dissipating fin and a light source fixing surface is disposed under the side of the diffusion sheet, a light source is disposed on the light source fixing surface to provide light, and a plurality of heat dissipating fins are disposed on the light source. The outer surface of the seat effectively prevents the thickness of the backlight module from increasing due to the fins and the light source being disposed directly under the diffuser. At the same time, the heat generated by the light source is transmitted through the light source fixing seat and the heat dissipation fin, which greatly reduces the working temperature of the backlight module. Moreover, the reflector and the light source reflector can effectively improve the light utilization efficiency of the backlight module. In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. However, the above description is only the preferred embodiment of the present invention, and equivalent modifications or variations made by those skilled in the art will be included in the following claims. BRIEF DESCRIPTION OF THE DRAWINGS The first figure is a schematic cross-sectional view of a direct-lit backlight module of the prior art; the second figure is a schematic view of the components of the direct-lit backlight module of the first embodiment of the present invention; 4 is a schematic cross-sectional view of the straight-type wire module shown in the third figure along the line IV_IV; FIG. 5 is a schematic cross-sectional view of the direct-type backlight module according to the second embodiment of the present invention; FIG. 7 is a schematic cross-sectional view of a direct type backlight module according to a third embodiment of the present invention; FIG. 7 is a cross-sectional view of a direct type backlight module according to a fourth embodiment of the present invention; FIG. 9 is a schematic cross-sectional view of a direct type backlight module according to a sixth embodiment of the present invention. [Main component symbol description] 9 1339294 Diffusion sheet 210, 510, 610 ' 710 Light source holder 220, 320, 420, 520, 620, 721, 723 Light source fixing surface 221 ' 321 ' 421 ' 521 ' 7211 ' 7231 Heat sink fin 225 Reflecting portion 5211' 5215 Reflecting surface 241, 5213, 5217, 541, 681, 741, 745 Light source 230, 530, 630, 731, 733 Reflecting plate 240, 340, 440, 540, 640, 740 Projection 742 Thermal medium layer 260 aluminum-based circuit board 270, 370 housing 280 '780 bottom surface 281, 781 side 283 opening 285 side opening 287 light source reflector 680 angle Θ, Θ 1 10