200940899 九、發明說明 【發明所屬之技術領域】 本發明係有關面光源裝置，更詳細者係有關以LED ( 發光二極體）作爲光源使用之面光源裝置。 【先前技術】 作爲組裝於液晶電視所使用之面光源裝置（3 )者， 〇 通常使用具備如圖1所示之光擴散板（1)與配置於其背 面側之光源（2)者，作爲光擴散板（1)者，由其無色、 薄型化之觀點視之，其厚度頂多2mm，且作爲光源（2 ) 者，使用冷陰極螢光管，近來由其省能源之觀點視之，亦 被提出以LED (發光二極體）作爲光源（2)之使用[「液 晶顯示用背光技術-液晶照明系統與構件一」、CMC出版 、2006 年 8 月 31 日發行、ρ·148~149]。 使用LED作爲光源時，同時使用對應光之三原色之 〇 紅色LED、綠色LED及藍色LED，由此等各LED之光係 透過光擴散板時進行混色，呈白色光，於面光源裝置（3 )之前面側進行出射。 惟，使用先行技術之光擴散板之面光源裝置時，其三 原色之光的混色不足。 【發明內容】 因此，本發明者爲開發一種以LED作爲光源之使用 ，使光的三原色充份混色之白色光可進行出射之面光源裝 -5- 200940899 置而進行精密硏討後結果，進而完成本發明。 亦即，本發明係提供一種具備光擴散板（1)、與配 置於該光擴散板（1)之背面側的LED光源（2 )，該光 擴散板（1)其總光線透光率（Tt)爲50~6 7%、厚度爲 2_5mm以上者爲其特徵之面光源裝置（3 )。 藉由本發明之面光源裝置，作成由LED之三原色的 光充份混色之白色光進行出射。 〇 【實施方式】 [發明實施之最佳形態] 作爲用於本發明面光源裝置（3)之光擴散板（1)者 ，通常使用未著色之無色（白色）者，其大小依其目的之 背光裝置、直立型液晶顯示裝置進行適度選擇，一般爲20 型（縱30cm、橫40cm)以上之較大面積者宜。 光擴散板（1)之厚度爲2.5mm以上，通常爲5mm以 下。當厚度未達2.5mm時，三原色之光混色不足，反之起 〇 出5mm則無法取得所期待之效果，對於薄型化之觀點不 利。 該光擴散板，例如將透明樹脂與擴散劑混練後，藉由 擠壓成形之擠壓成形法、射出成形之射出成形法、熱加壓 之熱加壓法等之一般的成形方法進行成形，所製造的。 作爲透明樹脂者如：聚碳酸酯樹脂、ABS樹脂（丙烯 腈-苯乙烯-丁二烯共聚物樹脂）、甲基丙烯酸樹脂、MS 樹脂（甲基丙烯酸甲酯-苯乙烯共聚物樹脂）、聚苯乙烯 -6- 200940899 樹脂、AS樹脂（丙烯腈-苯乙烯共聚物樹脂）' 聚乙烯、 聚丙烯等之聚烯烴樹脂等例。 作爲擴散劑例者，只要是構成光擴散板之透光性樹脂 與折射率爲不同之粒子，擴散透過光所得者即可，並未特 別限定，一般如：無機玻璃粒子、玻璃纖維、矽粒子 '氫 氧化鋁、碳酸鈣粒子、硫酸鋇粒子、氧化鈦粒子、滑石等 之無機粒子、亦可如：苯乙烯系聚合物粒子、丙烯酸系聚 ❹ 合物粒子、聚矽氧系聚合物粒子等之有機粒子。 光擴散劑的粒徑以重量平均粒徑計一般爲〇.8μιη以上 、ΙΟμιη以下者宜、較佳者爲2~3μιη。 光擴散板之總光線透光率（Tt)爲50%~67%。當未達 5 0%則亮度不足，超出67%則由LED之光混色不足。總光 線透光率（Tt )如所添加之光擴散劑之添加量愈多則Tt 愈小。總光線透光率（Tt )係依JIS K736 1 - 1 ( 1 997年） 爲基準所測定。 © 光源（2 )爲LED。作爲LED者，係使用其發光二極 體晶片以環氧樹脂製之樹脂所被覆之構造者，其指向性模 型可任意爲 Lambertian type、Batwing type、Side emitter type，較佳者爲 Lambertian type。 [實施例] 以下，藉由實施例，針對本發明進行詳細的說明。 [實施例1] 200940899 使用具備如圖1所示之光擴散板（1)、與配置於其 背面側之LED(2)之面光源裝置（3)。作爲光擴散板（ 1)者’係使用於100質量份之聚苯乙烯樹脂[東洋苯乙烯 公司製「東洋苯乙稀HRM40」、折射率1.59]中，加入2 質量份之光擴散劑[丙烯酸系交聯樹脂粒子、積水化成品 工業公司製「ΜΒΧ-2Η」、重量平均粒徑3μιη、折射率 1.49]進行混合後，以擠壓機「螺旋徑40mm」，2 1 0 〜250 °C下進行熔融混煉，經由給料裝置，由245 °C〜255 t Q 之T模擠壓成板狀所調製者。所使用之光擴散板之總光線 透光率（Tt )爲55%，厚度爲3mm。作爲LED ( 2 )者， 使用1個紅色LED。將此LED ( 2 )進行點燈，測定透過 光擴散板（1)之透過光的亮度外形，如圖2所示。圖2 所示之亮度外形中，横軸代表以LED ( 2 )之正上方爲原 點之測定位置爲止之距離（Distance )，縱軸代表測定位 置之亮度（Luminiance)。該面光源裝置（3)即使由 LED ( 2 )之正上方位置相隔20mm之位置中，仍顯示充份❹ 的亮度，其由LED之光充份擴散，因此使用對應光之三 原色之紅色LED、綠色LED、及藍色LED爲光源（3 )時 ，由此等LED之光充份混色後可作成白色光。 [實施例2] 將光擴散劑之使用量作成0 · 8 9質量份，與實施例1 同法，作成總光線透光率（Tt )爲55%、厚度爲4mm之光 擴散板（1)。接著’使用此之外’與實施例1作成相同 -8- 200940899 的面光源裝置（3)。此面光源裝置之亮度外形示於圖2。 該面光源裝置（3)即使於由LED (2)之正上方位置相隔 2 0 mm之位置中，仍顯示充份的亮度，由LED之光充份擴 散，因此使用紅色LED、綠色LED及藍色LED爲光源（3 )時，將由此等LED之光充份混色後，可作成白色光。 [比較例1] φ 將光擴散劑之使用量作成10質量份，與實施例1同 法，作成總光線透光率（Tt)爲55%、厚度爲1.5mm之光 擴散板（1)。接著’使用此之外’與實施例1同法作成 面光源裝置（3)。此面光源裝置之亮度外形示於圖2。該 面光源裝置其由LED (2)之正上方位置相通20mm之位 置之亮度低，故由LED之光擴散不足，使用紅色LED、 綠色LED及藍色LED爲光源時，由此等LED之光的混色 呈現不足，未能完全呈現白色光。 ❹ [比較例2] 將光擴散之使用量作成4·1質量份’與實施例1同法 ，作成總光線透光率（Tt)爲55 %、厚度爲2mm之光擴散 板（1)。接著，使用此之外’與實施例1同法作成相同 的面光源裝置。該面光源裝置之亮度外形示於圖2°該面 光源裝置其由LED (2)正上方之位置相隔20mm位置之 亮度低，故由LED之光擴散不足’使用紅色LED、綠色 LED、及藍色LED爲光源時’由此等LED之光混色呈現 200940899 不足者，未能完全呈現白色光。 [實施例3及實施例4] 將光擴散劑之使用量作成1.3質量份[實施例3]、及 0.7質量份[實施例4]，與實施例1同法，分別作成總光線 透光率（Tt)爲60%、厚度爲3 mm之光擴散板[實施例3] 及總光線透光率（Tt)爲60%、厚度爲4mm之光擴散板[ 實施例4]。接著，使用其之外，與實施例1同法作成相同 ❹ 的面光源裝置（3)。該面光源裝置之亮度外形示於圖3。 該面光源裝置（3)即使於由LED ( 2 )正上方之位置相隔 2 0mm位置中，仍顯示充足的亮度，由LED之光充份擴散 ，因此使用紅色LED、綠色LED、及藍色LED爲光源（3 )時，由此等之LED之光充份混色後，可作成白色光。 [比較例3及比較例4] 將光擴散劑之使用量作成4.5質量份[比較例3]、及 ❹ 2.4質量份[比較例4]，與實施例1同法，分別作成總光線 透光率（Tt)爲60%、厚度爲1.5mm之光擴散板[比較例 3]及總光線透光率（Tt)爲60%、厚度爲2 mm之光擴散板 [比較例4]。接著，使用其之外，與實施例1同法，作成 相同的面光源裝置（3)。該面光源裝置之亮度外形示於 圖3。該面光源裝置其由LED ( 2 )正上方位置相隔20mm 位置之亮度低，故由 LED之光擴散不足，使用紅色LED 、綠色LED、及藍色LED爲光源時，由此等LED之光的 -10- 200940899 混色呈現不足，未能完全呈現白色光。 [實施例5及實施例6] 將光擴散劑之使用量作成〇.8質量份[實施例5]及 0.5 5質量份[實施例6]，與實施例1同法，分別作成總光 線透光率（Tt)爲65%、厚度爲3mm之光擴散板[實施例 5]及總光線透光率（Tt)爲65%、厚度爲4mm之光擴散板 ❹ [實施例6]。接著，使用此等之外’與實施例1同法作成 相同之面光源裝置（3)。該面光源裝置之亮度外形示於 圖4。該面光源裝置（3 )即使於由LED ( 2 )正上方位置 相隔20mm位置中，仍顯示充足的亮度，由LED之光充份 擴散，因此使用紅色LED、綠色LED及藍色LED作爲光 源（3 )時，由此等LED之光充份混色後可作成白色光。 [比較例5及比較例6 ] φ 將光擴散劑之使用量作成3質量份[比較例5]及2質 量份[比較例6]，與實施例1同法，分別作成總光線透光 率（Tt)爲65%、厚度爲1.5mm之光擴散板[比較例5]及 總光線透光率（Tt)爲65%、厚度爲2mm之光擴散板[比 較例6]。接著，使用此等之外，與實施例1同法，作成相 同的面光源裝置（3)。該面光源裝置之亮度外形示於圖4 。該面光源裝置其由LED ( 2 )正上方位置相隔20mm位 置之亮度低，故由LED之光的擴散不足，使用紅色LED 、綠色LED及藍色LED爲光源時，由此等LED之光的混 200940899 色不足，未能完全呈現白色光。 [比較例7及比較例8] 將光擴散劑之使用量作成08質量份[比較例7]，及 0.53質量份[比較例8]，與實施例1同法，分別作成總光 線透光率（Tt)爲70%、厚度爲2mm之光擴散板[比較例 7]及總光線透光率（Tt)爲70%、厚度爲4mm之光擴散板 [比較例8]。接著，使用此等之外，與實施例1同法作成 ❹ 相同的面光源裝置（3)。該面光源裝置之亮度外形示於 圖5。該面光源裝置其由LED ( 2 )正上方位置相隔20mm 位置之亮度低，由LED之光擴散不足，故使用紅色LED 、綠色LED、及藍色LED爲光源時，由此等LED之光的 混色不足，未能完全呈現白色光。 [產業上可利用性] 藉由本發明面光源裝置，使用LED三原色之光充份 © 混色呈白色光進行出射。 【圖式簡單說明】 圖1代表本發明面光源裝置一例之模式的截面圖。 圖2代表實施例〗〜實施例2及比較例〗〜比較例2取 得之面光源裝置之亮度縱切面圖。 圖3代表實施例3〜實施例4及比較例3〜比較例4取 得之面光源裝置之亮度縱切面圖。 -12- 200940899 圖4代表實施例5〜實施例6及比較例5〜比較例6取 得之面光源裝置之亮度縱切面圖。 圖5代表比較例7~比較例8取得之面光源裝置之亮度 縱切面圖。 【主要元件符號說明】 1 :光擴散板 © 2 :光源（LED ) 3 :面光源裝置 -13-200940899 IX. Description of the Invention [Technical Field] The present invention relates to a surface light source device, and more particularly to a surface light source device using an LED (Light Emitting Diode) as a light source. [Prior Art] As a surface light source device (3) used for a liquid crystal television, a light diffusing plate (1) as shown in Fig. 1 and a light source (2) disposed on the back side thereof are generally used as The light diffusing plate (1) is viewed from the viewpoint of colorlessness and thinning, and has a thickness of at most 2 mm, and as a light source (2), a cold cathode fluorescent tube is used, which is recently viewed from the viewpoint of energy saving. It is also proposed to use LED (Light Emitting Diode) as the light source (2) ["LCD backlighting technology - LCD lighting system and component one", CMC Publishing, August 31, 2006, ρ·148~149 ]. When an LED is used as the light source, the magenta LED, the green LED, and the blue LED corresponding to the three primary colors of the light are simultaneously used, and when the light of each of the LEDs passes through the light diffusion plate, color mixing is performed, and white light is emitted to the surface light source device (3). ) The front side is emitted. However, when the surface light source device of the light diffusing plate of the prior art is used, the color mixture of the three primary colors is insufficient. SUMMARY OF THE INVENTION Therefore, the inventors of the present invention have developed a method in which the use of an LED as a light source and the white light of the three primary colors of the light can be mixed and emitted, and the surface light source is mounted in the light source -5 - 200940899. The present invention has been completed. That is, the present invention provides an LED light source (2) provided with a light diffusing plate (1) and disposed on the back side of the light diffusing plate (1), the light diffusing plate (1) having a total light transmittance ( Tt) is a surface light source device (3) characterized by 50 to 6 7% and a thickness of 2_5 mm or more. According to the surface light source device of the present invention, white light which is sufficiently mixed with light of the three primary colors of the LED is formed. [Embodiment] [Best Mode for Carrying Out the Invention] As the light diffusing plate (1) used in the surface light source device (3) of the present invention, an uncolored colorless (white) is usually used, and its size depends on its purpose. The backlight device and the upright liquid crystal display device are appropriately selected, and are generally suitable for a large area of 20 type (length 30 cm, width 40 cm) or more. The light diffusing plate (1) has a thickness of 2.5 mm or more, usually 5 mm or less. When the thickness is less than 2.5 mm, the color mixing of the three primary colors is insufficient, and when the thickness is 5 mm, the desired effect cannot be obtained, and the viewpoint of thinning is disadvantageous. The light-diffusing sheet is formed by, for example, kneading a transparent resin and a diffusing agent, and then molding by a general molding method such as an extrusion molding method, an injection molding injection molding method, or a hot pressurization hot press method. Made by. As a transparent resin, for example, polycarbonate resin, ABS resin (acrylonitrile-styrene-butadiene copolymer resin), methacrylic resin, MS resin (methyl methacrylate-styrene copolymer resin), poly Examples of styrene-6-200940899 resin, AS resin (acrylonitrile-styrene copolymer resin), polyolefin resin such as polyethylene or polypropylene. The diffusing resin constituting the light diffusing plate is not particularly limited as long as it is a particle having a refractive index different from that of the light-diffusing sheet, and is generally limited to, for example, inorganic glass particles, glass fibers, and cerium particles. The inorganic particles such as aluminum hydroxide, calcium carbonate particles, barium sulfate particles, titanium oxide particles, and talc may be, for example, styrene polymer particles, acrylic polymer particles, or polyoxymethylene polymer particles. Organic particles. The particle diameter of the light diffusing agent is generally 〇.8 μmη or more, ΙΟμιη or less, and preferably 2 to 3 μmη, based on the weight average particle diameter. The total light transmittance (Tt) of the light diffusing plate is 50% to 67%. When it is less than 50%, the brightness is insufficient. When it exceeds 67%, the color of the LED is insufficient. The total light transmittance (Tt) is as small as the added amount of the light diffusing agent added. The total light transmittance (Tt) is measured in accordance with JIS K736 1 - 1 (1999). © Light source (2) is an LED. As the LED, a structure in which a light-emitting diode wafer is coated with a resin made of an epoxy resin is used, and the directivity model can be arbitrarily a Lambertian type, a Batwing type, or a Side emitter type, preferably a Lambertian type. [Examples] Hereinafter, the present invention will be described in detail by way of examples. [Embodiment 1] 200940899 A surface light source device (3) including a light diffusing plate (1) as shown in Fig. 1 and an LED (2) disposed on the back side thereof is used. As a light diffusing plate (1), it is used in 100 parts by mass of a polystyrene resin [Toyo Phenylene Ethylene HRM40 manufactured by Toyo Styrene Co., Ltd., refractive index: 1.59], and 2 parts by mass of a light diffusing agent [acrylic acid] is added. The crosslinked resin particles, "ΜΒΧ-2Η" manufactured by Sekisui Kogyo Co., Ltd., weight average particle diameter 3μιη, refractive index 1.49] were mixed, and then the extruder "spiral diameter 40mm", 2 1 0 to 250 °C The mixture was melt-kneaded and extruded into a plate shape by a T die of 245 ° C to 255 t Q via a feeding device. The light diffusing plate used had a total light transmittance (Tt) of 55% and a thickness of 3 mm. As the LED (2), one red LED is used. This LED (2) was turned on, and the brightness profile of the transmitted light transmitted through the light diffusing plate (1) was measured, as shown in Fig. 2. In the luminance profile shown in Fig. 2, the horizontal axis represents the distance (Distance) from the measurement position directly above the LED (2), and the vertical axis represents the luminance (Luminiance) of the measurement position. The surface light source device (3) displays a sufficient brightness even if it is separated by a position of 20 mm from the position directly above the LED (2), and is sufficiently diffused by the light of the LED, so that a red LED corresponding to the three primary colors of light is used. When the green LED and the blue LED are the light source (3), the light of the LEDs can be whitened after being sufficiently mixed. [Example 2] A light diffusing plate (1) having a total light transmittance (Tt) of 55% and a thickness of 4 mm was prepared in the same manner as in Example 1 using a light diffusing agent in an amount of 0·89 parts by mass. . Next, the surface light source device (3) of the same -8-200940899 was created as in Example 1 except that 'the outside of this' was used. The brightness profile of this surface light source device is shown in Figure 2. The surface light source device (3) displays sufficient brightness even in a position separated by 20 mm from the position directly above the LED (2), and is sufficiently diffused by the light of the LED, so that the red LED, the green LED, and the blue are used. When the color LED is the light source (3), the light of the LEDs can be mixed and colored, and white light can be formed. [Comparative Example 1] φ The amount of the light diffusing agent used was 10 parts by mass, and a light diffusing plate (1) having a total light transmittance (Tt) of 55% and a thickness of 1.5 mm was prepared in the same manner as in Example 1. Then, the surface light source device (3) was fabricated in the same manner as in the first embodiment. The brightness profile of this surface light source device is shown in Figure 2. The surface light source device has a low luminance at a position where the position directly above the LED (2) is 20 mm, so that light diffusion from the LED is insufficient, and when the red LED, the green LED, and the blue LED are used as the light source, the LED light is thereby used. The color mixture is not enough to render white light completely. [Comparative Example 2] The amount of light diffusion used was changed to 4.1 parts by mass. In the same manner as in Example 1, a light diffusing plate (1) having a total light transmittance (Tt) of 55 % and a thickness of 2 mm was prepared. Then, the same surface light source device as that of the first embodiment was used. The brightness profile of the surface light source device is shown in Fig. 2°. The surface light source device has a low brightness of 20 mm from the position directly above the LED (2), so the light diffusion from the LED is insufficient 'using red LED, green LED, and blue When the color LED is a light source, the light color mixture of the LEDs is not sufficient for the 200940899, and the white light is not completely displayed. [Example 3 and Example 4] The amount of the light diffusing agent used was 1.3 parts by mass [Example 3] and 0.7 parts by mass [Example 4], and the total light transmittance was respectively obtained in the same manner as in Example 1. (Tt) is a light diffusing plate of 60% and a thickness of 3 mm [Example 3] and a light diffusing plate having a total light transmittance (Tt) of 60% and a thickness of 4 mm [Example 4]. Next, using the same method as in Example 1, the same surface light source device (3) was used. The brightness profile of the surface light source device is shown in FIG. The surface light source device (3) displays sufficient brightness even in a position separated by 20 mm from the position directly above the LED (2), and is sufficiently diffused by the light of the LED, so that the red LED, the green LED, and the blue LED are used. When the light source (3) is used, the light of the LEDs thus obtained is sufficiently mixed, and white light can be formed. [Comparative Example 3 and Comparative Example 4] The amount of the light diffusing agent used was 4.5 parts by mass [Comparative Example 3] and ❹ 2.4 parts by mass [Comparative Example 4], and the total light was transmitted in the same manner as in Example 1. A light diffusing plate having a ratio (Tt) of 60% and a thickness of 1.5 mm [Comparative Example 3] and a light diffusing plate having a total light transmittance (Tt) of 60% and a thickness of 2 mm [Comparative Example 4]. Next, in the same manner as in Example 1, except that the same, the same surface light source device (3) was produced. The brightness profile of the surface light source device is shown in Fig. 3. The surface light source device has a low luminance at a position separated by 20 mm from the position directly above the LED (2), so that light diffusion from the LED is insufficient, and when the red LED, the green LED, and the blue LED are used as the light source, the light of the LED is thereby -10- 200940899 The color mixture is not enough to fully display white light. [Example 5 and Example 6] The amount of the light diffusing agent used was set to 8 parts by mass [Example 5] and 0.5 5 parts by mass [Example 6], and the same method as in Example 1 was used to prepare total light permeation. A light diffusing plate having a light transmittance (Tt) of 65% and a thickness of 3 mm [Example 5] and a light diffusing plate having a total light transmittance (Tt) of 65% and a thickness of 4 mm [Example 6]. Next, the same surface light source device (3) as that of the first embodiment was used except for the above. The brightness profile of the surface light source device is shown in Fig. 4. The surface light source device (3) displays sufficient brightness even in a position separated by 20 mm from the position directly above the LED (2), and is sufficiently diffused by the light of the LED, so that the red LED, the green LED, and the blue LED are used as the light source ( 3), when the light of the LED is sufficiently mixed, white light can be formed. [Comparative Example 5 and Comparative Example 6] φ The amount of the light diffusing agent used was 3 parts by mass [Comparative Example 5] and 2 parts by mass [Comparative Example 6], and the total light transmittance was respectively obtained in the same manner as in Example 1. (Tt) was a light diffusing plate of 65% and a thickness of 1.5 mm [Comparative Example 5] and a light diffusing plate having a total light transmittance (Tt) of 65% and a thickness of 2 mm [Comparative Example 6]. Then, the same surface light source device (3) was produced in the same manner as in Example 1 except using these. The brightness profile of the surface light source device is shown in Figure 4. The surface light source device has a low luminance at a position separated by 20 mm from the position directly above the LED (2), so that the light from the LED is insufficiently diffused, and when the red LED, the green LED, and the blue LED are used as the light source, the light of the LED is thereby Mixed 200940899 is not enough color to fully display white light. [Comparative Example 7 and Comparative Example 8] The amount of the light diffusing agent used was made into 08 parts by mass [Comparative Example 7] and 0.53 parts by mass [Comparative Example 8], and the total light transmittance was respectively obtained in the same manner as in Example 1. (Tt) was a light diffusing plate having a thickness of 70% and a thickness of 2 mm [Comparative Example 7] and a light diffusing plate having a total light transmittance (Tt) of 70% and a thickness of 4 mm [Comparative Example 8]. Next, the same surface light source device (3) as that of the first embodiment was used in the same manner as in the first embodiment. The brightness profile of the surface light source device is shown in Fig. 5. The surface light source device has a low luminance of 20 mm from the position directly above the LED (2), and the light diffusion of the LED is insufficient. Therefore, when the red LED, the green LED, and the blue LED are used as the light source, the light of the LED is thereby Insufficient color mixing, not fully white light. [Industrial Applicability] With the surface light source device of the present invention, the light of the three primary colors of the LED is used to make full use. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing an example of a surface light source device of the present invention. Fig. 2 is a longitudinal sectional view showing the brightness of the surface light source device obtained in Example ～ to Example 2 and Comparative Example ～ to Comparative Example 2. Fig. 3 is a longitudinal sectional view showing the brightness of the surface light source device obtained in Example 3 to Example 4 and Comparative Example 3 to Comparative Example 4. -12- 200940899 Fig. 4 is a longitudinal sectional view showing the brightness of the surface light source device obtained in Example 5 to Example 6 and Comparative Example 5 to Comparative Example 6. Fig. 5 is a longitudinal sectional view showing the brightness of the surface light source device obtained in Comparative Example 7 to Comparative Example 8. [Main component symbol description] 1 : Light diffuser © 2 : Light source (LED) 3 : Surface light source device -13-