201235196 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種決定光學構件之凹凸形狀之方法。 又’本發明係關於一種製造利用有該方法之光學構件之方 法。 【先前技術】 導光板、光擴散板等光學片材於其表面具有用以發揮所 需之光學特性而設計之凹凸形狀。作為製造具有凹凸形狀 之光學片材之方法，已知有於連續樹脂片材之表面轉印轉 印模之形狀之方法（例如專利文獻”。 先前技術文獻 專利文獻 專利文獻1:日本專利特開20〇9·22〇555號公報 【發明内容】 發明所欲解決之問題 如光學片材之光學構件之凹凸形狀通常係藉由模擬對凹 凸形狀進行設計，且谁抖目士〜 遇仃具有所設計之凹凸形狀之試製品 之製作及其評價，而最伟仆 ^ ^ 取彳圭化°為達到所需之光學特性必需 精密地對凹凸形狀進扞網 订調整，因此為了凹凸形狀之最佳 化，會存在較多之對試劁0 a表。。之製作及其評價進行反覆試誤 之情形。 但是，利用先前之方沐立 & 在每次製作試製品時均須重新製作 轉印模，因此實際狀況3五 疋馬了凹凸形狀之最佳化需要極大 之費用及時間。 161653.doc 201235196 因此，本發明之主要目的在於提供一種用以 定光學構件之凹凸形狀之方法。 簡早地决 解決問題之技術手段 本發明係關於一種決定光學構件之凹凸形狀之方法，其 包含：將試製用轉印模之形狀以不同之轉印率進行轉印， 藉此成形複數個具有相互不同之凹凸形狀之光學構件試製 品之步驟；對光學構件試製品各自之光學特性進行評價之 步驟；及基於光學特性決定光學構件之凹凸形狀之步驟。 根據上述本發明之方法，藉由使成形時之轉印率產生變 化而準備複數個凹凸形狀不同之試製品，因此為準備試製 品無須重新製作試製用轉印模。因此，較先前可更簡單地 決定光學構件之凹凸形狀。 於其他態樣中，本發明係關於一種光學構件之製造方 法。本發明之製造方法包含藉由自光學構件製造用轉印模 之轉印而成形光學構件之步驟，該光學構件製造用轉印模 具有與藉由上述方法而決定之凹凸形狀相對應之反轉形 狀。 根據上述本發明之製造方法，可簡單地準備光學構件製 造用轉印模，因此可更有效率地製造具有優良之光學特性 之光學構件。 為了穩定地製造光學構件，光學構件製造用轉印模較佳 為具有於以90。/。以上之轉印率進行轉印時形成光學構件之 凹凸形狀之反轉形狀。 發明之效果 161653.doc 201235196 根據本發明，提供一種用以更簡單地決定光學構件之凹 λ形狀之方法。 【實施方式】 以下，對本發明之較佳實施形態詳細地進行說明。但 是，本發明並不限定於以下實施形態。 圖1係表示光學構件即光學片材之一實施形態之立體 圖°圖1中所示之光學片材30包括具有俯視形狀為矩形之 一對主面。一側之主面S1形成有具有複數個凸狀部35之凹 凸形狀。凸狀部35於沿光學片材30之主面之一邊之方向延 伸’且正交於凸狀部35之延伸方向之剖面之形狀為山型。 複數個凸狀部35並列配置於垂直於其延伸方向之方向上。 具有凸狀部35之凹凸形狀藉由自轉印模之轉印而形成。 光學片材30例如可作為搭載於透過型圖像裝置中之面光 源裝置（背光裝置）之導光板，或用以將來自光源之光均勻 地擴散之光擴散板而使用。於將光學片材3〇作為導光板而 使用之情形時，例如，將來自光源之光自側面33射入至光 牟片材30内，且將面狀之光自具有凹凸形狀之主面Si射 出於將光學片材3 0作為光擴散板而使用之情形時，例 如，將光源配置於主面s 1之反面之背面S2側。 光學片材30主要係包含透明材料之透光性片材。透明材 料之折射率通常為L48以上i.62以下或156以上162以下。 作為透明材料，可例示透明樹脂及透明玻璃。 於光擴散板之情形時’透明樹脂較佳為自聚碳酸醋樹脂 (折射率：咖㈣）樹脂（甲 161653.doc 201235196 基丙稀酸曱酯-苯乙烯共聚物樹脂）(折射率：丨56〜丨59) AS(Acrylonitrile Styrene)樹脂（丙烯腈-苯乙烯共聚合體樹 脂）（折射率：1.56〜1.59)、聚苯乙烯樹脂（折射率：j 59)、 及環烯樹脂（折射率1.51〜1.55)中選擇。於導光/ ' U似·疋情形 時’透明樹脂較佳為聚甲基丙婦酸甲醋（pmma， PolymethylMethacrylate)樹脂。 於使用透明樹脂作為透明材料之情形時，光學片材扣亦 可包含紫外線吸收劑、抗靜電劑、抗氧化劑、加工穩定 劑、阻燃劑及潤滑劑等添加劑。該些添加劑可分別單獨使 用’或可將2種以上加以組合而使用。 作為紫外線吸收劑，例如可例舉苯并三唑系紫外線吸收 劑、二苯甲酮系紫外線吸收劑、氰基丙烯酸酯系紫外線吸 收知]丙一酸酯系紫外線吸收劑、草酸醯替苯胺系紫外線 吸收劑、三畊系紫外線吸收劑等。該些中較佳為笨并三唑 系紫外線吸收劑及三啡系紫外線吸收劑。 光學片材30亦可包含光擴散劑。作為光擴散劑，可較佳 地使用折射率與主要構成光學片材％之上述透明材料不同 之粒子。作為光擴散劑，例如可使用苯乙烯樹脂粒子、甲 稀酉夂樹月曰粒+等有機粒子，碳酸奸粒子、石夕粒子等益 機粒子。光擴散劑之粒徑通常為Ο—〜’’’、 圖1係表示製造光學片材之方法之一實施形態之模式 圖》精由圖2令所示之光學片材製造裝置5〇,具有凹凸形 =光學片材3G藉由樹脂之擠壓成形而成形。光學片材製 、置50主要包括：對加熱炫融狀態之樹脂進行擠廢之擠 161653.doc 201235196 壓機58 ;安裝於擠壓機58上且用以將樹脂投入之樹脂投入 口 57 ;將藉由擠壓機58而擠壓出之樹脂排出並形成連續樹 脂片材3之壓模51 ;於壓模51之下游側相互隔開而依序配 置有之預壓軋輥52 '第1擠壓軋輥52A及第2擠壓軋輥 52B。於第2擠壓軋輥52B之周面形成有對應於光學片材3〇 之凹凸形狀之轉印模53。 自壓模51排出之連續樹脂片材3通過預壓軋輥52d與第1 擠壓軋輥52A之間。連續樹脂片材3之厚度主要係藉由預壓 軋輥52D與第1擠壓軋輥52A之間隔而控制。於連續樹脂片 材3傳送至該些軋輥之間之位置上，形成經熔融之樹脂滯 留之熔融壁4之情況較多。 通過預壓軋輥52D與第1擠壓軋輥52a之間之連續樹脂片 材3於第1擠壓軋輥52A之周面上被搬送至於第2擠壓軋輥 52A與第2擠壓軋輥52B之間受到擠壓之位置。 連續Μ月曰片材3於通過第1擠壓乾輥52a與第2擠壓軋報 52B之間時受到自厚度方向之兩側擠壓，從而使轉印模53 之形狀轉印至連續樹脂片材3之表面（主面）81上。形狀經 轉印之連續樹脂片材3於第2擠壓軋輥52B之周面上一面被 冷卻-面被搬送之後，作為光學片材3〇拉取。於光學片材 3〇之一側之主面S1上，形成有自轉印模53轉印之凹凸形 狀。 於光學片材30成形為光學構件試製品之情形時，使用試 製用轉印模53’ 一面改變轉印率一面進行複數次成形，藉 此製作複數個具有相互不同之凹凸形狀之試製品。 I61653.doc 201235196 圖3係表示成形作為光學構件試製品之光學片材3 〇之步 驟之一實施形態之模式圖。如圖3(a)所示，轉印模53具有 與光學構件30之具有凹凸形狀之凸狀部35相對應且形成有 深度hi之槽即凹部53a之反轉形狀。如圖3(b)所示，將連續 樹脂片材3進行擠壓並填充至凹部53&内。以樹脂密接於轉 印模53之狀態而形成於凹部53a内之凸狀部35之高度h2小 於最大深度hi，因此於樹脂與轉印模53之間殘留有空隙。 亦有將樹脂全部填充至凹部53a内之後，成為hl = h2之情 形。將樹脂溫度降低某個程度之後，光學片材3 〇自轉印模 53脫離°其後’樹脂由於熱彈性變形而收縮，故而樹脂固 化狀態之光學片材3 〇之凸狀部3 5之高度h3變為小於高度 h2。於填充率（112/111)較小時，亦有較多之最終之凸狀部35 之邊緣部形狀正確反映轉印模之形狀之情形。 轉印率（°/〇)可定義為藉由式：（h3/hl)xl〇〇而算出之值。 藉由使§亥轉印率於例如3 〇〜i 〇〇%之範圍内進行變化，可簡 單地且於短期時間内自一種轉印模製作複數種具有多樣化 凹凸形狀之試製品。 為使本領域技術人員理解，根據轉印模之形狀之轉印率 可藉由適當調整光學片材之成形條件而控制。例如，存在 有者眼於向轉印模之凹部53a填充之樹脂之填充率（h2/hl) 而"又疋條件之方法。藉由該方法，例如，於提昇自壓模排 出之樹脂之溫度時，於提昇產線速度時，於縮小熔融壁 時，或者於提昇具有轉印模之擠壓軋輥之溫度時，填充時 之樹脂之流動性變大，因此存在轉印率變大之傾向。或 161653.doc 201235196 者，亦可著眼於脫模後之樹脂之熱彈性變形之程度（h3/h2) 而設定軋輥溫度、產線速度等條件。 於圖3所示之實施形態中，雖然轉印模之凹部之剖面形 狀為包含曲線之山型，但是轉印模之形狀並不限定於此。 例如，可較佳地使用具有剖面形狀為三角稜鏡形狀之凹部 之轉印模。藉由使用複數種三角稜鏡形狀之底角不同之轉 印模，可於短期時間内簡單地製作光學特性不同之多樣化 試製品。 亦可準備複數種具有不同之凹凸形狀之轉印才莫，且對各 個轉印模以不同之轉印率成形試製品。亦可使用包含複數 個凹凸形狀不同之區域之轉印模。因事先準備複數種具有 不同之凹凸形狀之轉印帛’故可於設計新的《學片材時不 重新製作轉印模而於短期時間内製作多樣化凹凸形狀之試 製品。 進而可於製作試製品時藉由使構成光學 片材之材料等 產生變化而更有效率地使光學片材最佳化。例如，可調整 光擴散劑之折射率、粒徑及濃度，進而光學片材表面之壓 紋加工之特性。 與對忒製各自之光學特性進行評價，且將各試製品之光 子特I·生及作為目標之光學特性進行比較，可將良好地達成 所而之光學特性之凹凸形狀決定為於製造產品之光學構件 時設定為目標之凹凸形狀。4見需要，一面改變轉印模之形 狀及轉印率箸 f 曲反覆進行成形試製品之步驟及評價各試 製品之光學特· 之步驟’而將光學片材之凹凸形狀最佳化 161653.doc 201235196 及根據情形將材料構成、壓紋加工等最佳化 自試製品中選擇合格品並自例如。 Λ ^ 射出光之不均勻性、宾 度、總透光率及霧度中選擇作為用以決定凹凸形狀之^ 之光學特性。通常，較理想的是射出光之面内不均勾性^ 小（均勻性較高）者’而亮度較理想的是於射出光之均= 無顯者受損之範圍内較高者。光學特性之評價亦可於组入 至設想使用之面光源裝置等中之狀態下進行。視需要：併 用剖面形狀觀察、模擬等將光學片材最佳化。 藉由以上所述之方法，達成作為目標之光學特性之光學 片材之設計完成之後’準備具有對應於其凹凸形狀之反轉 形狀之光學構件製造用轉印模。例如，以如下方式製作轉 印模：即，藉由光學顯微鏡等對判斷為具有作為目標之凹 凸形狀且作為；^準品之試製品之剖面形狀進行觀察，並藉 由轉印形成具有所觀察之剖面形狀之凹凸形狀。或者，亦 可製=作為標準品之試製品之複製品，且製作該複製品之 複製时’進而製作其電鑄模。藉由自光學構件製造用轉印 模之轉印，製造作為產品之光學片材。 為了穩定地製造光學構件，光學構件製造用轉印模具有 於以較佳為90%以上，更佳為95%以上之轉印率進行轉印 夺形成作為目標之凹凸形狀之反轉形狀。若以轉印率較低 '、牛進行成形，則存在產品之不均變大之傾向。雖然於 試製階段未成為問題，但是強烈希望於量產時產品之不均 儘量小。 本發明並不限定於以上所說明之實施形態，於不脫離本 161653.doc 201235196 發明之主旨的範圍内可進行適當變形。例如光學片材之產 品或試製品之成形方法不限定於擠壓成形，亦可為射出成 形等其他成形方法。藉由本發明而決定之凹凸形狀並不限 定於如圖1之光學片材之1維雙凸透鏡，例如可藉由本發明 決定微透鏡、棱錐型棱鏡等2維凹凸形狀。又，藉由本發 明而決定凹凸形狀之光學片材並不限定於導光板及光擴散 板，例如亦可為其他面光源裝置用光學薄膜、Α(}(α^201235196 VI. Description of the Invention: [Technical Field of the Invention] The present invention relates to a method of determining the uneven shape of an optical member. Further, the present invention relates to a method of manufacturing an optical member using the method. [Prior Art] An optical sheet such as a light guide plate or a light diffusing plate has a concavo-convex shape designed to exhibit desired optical characteristics on its surface. As a method of producing an optical sheet having a concavo-convex shape, a method of transferring a shape of a transfer mold on the surface of a continuous resin sheet is known (for example, a patent document). PRIOR ART DOCUMENT Patent Document Patent Document 1: Japanese Patent Laid-Open 〇 · · · 〇 〇 【 【 【 【 【 【 【 【 【 【 【 【 【 【 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学The design and evaluation of the design of the concave-convex shape of the design, and the most versatile servant ^ ^ 彳 彳 彳 ° To achieve the required optical characteristics must be precisely adjusted for the concave and convex shape, so the best shape for the concave and convex There will be more cases of trials and tests. The production and evaluation of the trials will be repeated. However, with the previous party, Muli & must re-create the transfer mold every time the prototype is made. Therefore, the actual situation is that the optimization of the concave and convex shape requires a great cost and time. 161653.doc 201235196 Therefore, the main object of the present invention is to provide a BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining a concavo-convex shape of an optical member, comprising: transferring a shape of a transfer mold for trial production at a different transfer rate a step of forming a plurality of optical member prototypes having mutually different uneven shapes, a step of evaluating optical characteristics of the optical member prototypes, and a step of determining the uneven shape of the optical members based on the optical characteristics. According to the method of the present invention, a plurality of prototypes having different uneven shapes are prepared by changing the transfer rate during molding. Therefore, it is not necessary to reproduce the transfer mold for trial production in preparation for the prototype. In other aspects, the present invention relates to a method of manufacturing an optical member. The manufacturing method of the present invention includes the step of forming an optical member by transfer from a transfer mold for manufacturing an optical member. The transfer mold for manufacturing an optical member has a concave-convex shape determined by the above method According to the manufacturing method of the present invention described above, the transfer mold for optical member manufacturing can be easily prepared, so that an optical member having excellent optical characteristics can be more efficiently produced. In order to stably manufacture an optical member, optical The transfer mold for manufacturing a member preferably has an inverted shape in which the uneven shape of the optical member is formed at a transfer rate of 90% or more. Effect of the Invention 161653.doc 201235196 According to the present invention, a use is provided. The preferred embodiment of the present invention will be described in detail with reference to the preferred embodiments of the present invention. However, the present invention is not limited to the following embodiments. That is, a perspective view of one embodiment of the optical sheet. The optical sheet 30 shown in Fig. 1 includes a pair of main faces having a rectangular shape in plan view. The main surface S1 of one side is formed with a concave convex shape having a plurality of convex portions 35. The shape of the cross section of the convex portion 35 extending in the direction of one side of the main surface of the optical sheet 30 and orthogonal to the extending direction of the convex portion 35 is a mountain shape. The plurality of convex portions 35 are arranged side by side in a direction perpendicular to the extending direction thereof. The uneven shape having the convex portion 35 is formed by transfer from a transfer mold. The optical sheet 30 can be used, for example, as a light guide plate of a surface light source device (backlight device) mounted in a transmissive image device, or as a light diffusing plate for uniformly diffusing light from a light source. When the optical sheet 3 is used as a light guide plate, for example, light from a light source is incident from the side surface 33 into the aperture sheet 30, and the planar light is self-contained from the main surface Si having the uneven shape. When the optical sheet 30 is used as a light diffusing plate, for example, the light source is disposed on the back surface S2 side of the reverse surface of the main surface s 1 . The optical sheet 30 is mainly a light transmissive sheet containing a transparent material. The refractive index of the transparent material is usually L48 or more and i.62 or less or 156 or more and 162 or less. As a transparent material, a transparent resin and a transparent glass can be illustrated. In the case of a light diffusing plate, the transparent resin is preferably a self-polycarbonate resin (refractive index: coffee (4)) resin (A 161653.doc 201235196 acrylic acid acrylate-styrene copolymer resin) (refractive index: 丨56~丨59) AS (Acrylonitrile Styrene) resin (acrylonitrile-styrene copolymer resin) (refractive index: 1.56 to 1.59), polystyrene resin (refractive index: j 59), and cycloolefin resin (refractive index 1.51) Choose from ~1.55). The transparent resin is preferably a pmma (polymethylMethacrylate) resin in the case of light guiding/'U-like 疋. In the case where a transparent resin is used as the transparent material, the optical sheet fastener may also contain additives such as an ultraviolet absorber, an antistatic agent, an antioxidant, a processing stabilizer, a flame retardant, and a lubricant. These additives may be used singly or in combination of two or more kinds. Examples of the ultraviolet absorber include, for example, a benzotriazole-based ultraviolet absorber, a benzophenone-based ultraviolet absorber, and a cyanoacrylate-based ultraviolet absorber; a propionate-based ultraviolet absorber; and a oxalic acid-based anilide system. Ultraviolet absorber, three-plowed UV absorber, etc. Among these, a stupid triazole-based ultraviolet absorber and a tri-morphic ultraviolet absorber are preferred. The optical sheet 30 may also contain a light diffusing agent. As the light diffusing agent, particles having a refractive index different from that of the above-mentioned transparent material mainly constituting % of the optical sheet can be preferably used. As the light diffusing agent, for example, organic particles such as styrene resin particles or eucalyptus eucalyptus particles, and organic particles such as carbonated particles and Shiray particles can be used. The particle size of the light diffusing agent is generally Ο-〜''', and FIG. 1 is a schematic view showing an embodiment of a method for producing an optical sheet. The optical sheet manufacturing apparatus shown in FIG. Concavo-convex shape = The optical sheet 3G is formed by extrusion molding of a resin. The optical sheet manufacturing and setting 50 mainly comprises: squeezing the resin in a state of heating and squeezing; 161653.doc 201235196 press 58; a resin input port 57 mounted on the extruder 58 for putting the resin into the resin; The resin extruded by the extruder 58 is discharged to form a stamper 51 of the continuous resin sheet 3; on the downstream side of the stamper 51, the pre-nip rolls 52' first extrusion are sequentially disposed. Roller 52A and second press roll 52B. A transfer mold 53 corresponding to the uneven shape of the optical sheet 3 is formed on the circumferential surface of the second pressing roll 52B. The continuous resin sheet 3 discharged from the stamper 51 passes between the pre-nip roll 52d and the first press roll 52A. The thickness of the continuous resin sheet 3 is mainly controlled by the interval between the pre-pressing roll 52D and the first pressing roll 52A. In the case where the continuous resin sheet 3 is conveyed to a position between the rolls, the molten wall 4 in which the molten resin is retained is formed in a large amount. The continuous resin sheet 3 between the pre-pressing roll 52D and the first pressing roll 52a is conveyed to the circumferential surface of the first pressing roll 52A to be received between the second pressing roll 52A and the second pressing roll 52B. The position of the extrusion. The continuous stencil sheet 3 is pressed from both sides in the thickness direction when passing between the first squeezing dry roll 52a and the second squeezing roll 52B, thereby transferring the shape of the transfer mold 53 to the continuous resin. The surface (main surface) 81 of the sheet 3 is placed. The continuous resin sheet 3 whose shape has been transferred is conveyed on the peripheral surface of the second pressing roll 52B by the cooling surface, and then taken up as an optical sheet 3〇. On the main surface S1 on one side of the optical sheet 3, a concavo-convex shape transferred from the transfer mold 53 is formed. In the case where the optical sheet 30 is molded into an optical member prototype, the trial transfer mold 53' is used to form a plurality of moldings having mutually different uneven shapes while changing the transfer rate. I61653.doc 201235196 Fig. 3 is a schematic view showing an embodiment of a step of forming an optical sheet 3 as an optical member prototype. As shown in Fig. 3 (a), the transfer mold 53 has an inverted shape in which a concave portion 53a which is a groove having a depth hi is formed corresponding to the convex portion 35 having the uneven shape of the optical member 30. As shown in Fig. 3 (b), the continuous resin sheet 3 is pressed and filled into the recesses 53 & The height h2 of the convex portion 35 formed in the concave portion 53a in a state in which the resin is in close contact with the transfer mold 53 is smaller than the maximum depth hi, so that a gap remains between the resin and the transfer mold 53. Further, after the resin is completely filled into the concave portion 53a, it becomes a shape of hl = h2. After the temperature of the resin is lowered to some extent, the optical sheet 3 is detached from the transfer mold 53. Thereafter, the resin shrinks due to thermoelastic deformation, so the height h3 of the convex portion 35 of the optical sheet 3 in the cured state of the resin is h3. It becomes smaller than the height h2. When the filling rate (112/111) is small, there are many cases where the shape of the edge portion of the final convex portion 35 correctly reflects the shape of the transfer mold. The transfer rate (°/〇) can be defined as a value calculated by the formula: (h3/hl)xl〇〇. By changing the transfer rate in the range of, for example, 3 〇 to i 〇〇%, it is possible to easily produce a plurality of prototypes having various irregularities from a transfer mold in a short period of time. To enable those skilled in the art to understand, the transfer rate according to the shape of the transfer mold can be controlled by appropriately adjusting the molding conditions of the optical sheet. For example, there is a method in which the filling rate (h2/hl) of the resin filled in the concave portion 53a of the transfer mold is "the condition". By the method, for example, when raising the temperature of the resin discharged from the stamper, when the line speed is increased, when the molten wall is reduced, or when the temperature of the press roll having the transfer mold is raised, the filling is performed. Since the fluidity of the resin is increased, the transfer rate tends to increase. Or 161653.doc 201235196, you can also set the conditions such as roll temperature and line speed by focusing on the degree of thermoelastic deformation of the resin after demolding (h3/h2). In the embodiment shown in Fig. 3, the shape of the concave portion of the transfer mold is a mountain shape including a curved line, but the shape of the transfer mold is not limited thereto. For example, a transfer mold having a concave portion having a triangular cross-sectional shape can be preferably used. By using a plurality of transfer dies having different base angles, it is possible to easily produce diversified prototypes having different optical characteristics in a short period of time. A plurality of transfer patterns having different uneven shapes may be prepared, and the test pieces may be formed at different transfer rates for the respective transfer molds. A transfer mold including a plurality of regions having different irregularities may also be used. Since a plurality of transfer embossings having different concavo-convex shapes are prepared in advance, it is possible to produce a variety of concave and convex shapes in a short period of time without designing a transfer mold when designing a new "study sheet". Further, it is possible to more efficiently optimize the optical sheet by changing the material constituting the optical sheet or the like at the time of producing the prototype. For example, the refractive index, particle size, and concentration of the light diffusing agent can be adjusted to further characterize the embossing of the surface of the optical sheet. By evaluating the optical characteristics of each of the tantalum products, and comparing the photon characteristics of each of the prototypes with the target optical characteristics, it is possible to determine the uneven shape of the optical characteristics that are satisfactorily achieved as the manufactured product. The optical member is set to the target uneven shape. 4 If necessary, the shape and transfer rate of the transfer mold are changed, and the steps of forming the prototype and the step of evaluating the optical characteristics of each sample are repeated to optimize the concave and convex shape of the optical sheet. Doc 201235196 and, depending on the situation, select a qualified product from the material composition, embossing, etc., and select the qualified product from, for example. Λ ^ The non-uniformity of the emitted light, the bin, the total light transmittance, and the haze are selected as the optical characteristics for determining the uneven shape. In general, it is preferable that the unevenness in the plane of the emitted light is small (higher uniformity), and the brightness is preferably higher in the range of the emitted light = no damage. The evaluation of the optical characteristics can also be carried out in a state in which it is incorporated in a surface light source device or the like that is supposed to be used. Depending on the need: The optical sheet is optimized by cross-sectional shape observation, simulation, and the like. After the design of the optical sheet as the target optical characteristic is completed by the above-described method, the transfer mold for manufacturing an optical member having an inverted shape corresponding to the uneven shape is prepared. For example, a transfer mold is produced by observing a cross-sectional shape of a prototype which is determined to have a target uneven shape by an optical microscope or the like, and is observed by transfer formation. The concave and convex shape of the cross-sectional shape. Alternatively, it is also possible to produce a replica of a prototype as a standard, and to make an electroformed mold when the replica is produced. An optical sheet as a product is produced by transfer from a transfer mold for optical member manufacturing. In order to stably manufacture the optical member, the transfer mold for producing an optical member is formed by transferring at a transfer rate of preferably 90% or more, more preferably 95% or more, to form an inverted shape of the target uneven shape. If the transfer rate is low, and the cow is molded, there is a tendency that the unevenness of the product becomes large. Although it has not been a problem during the trial production phase, it is strongly expected that the unevenness of the product during mass production should be as small as possible. The present invention is not limited to the embodiments described above, and can be appropriately modified without departing from the gist of the invention of 161653.doc 201235196. For example, the product of the optical sheet or the molding method of the prototype is not limited to extrusion molding, and may be other molding methods such as injection molding. The concavo-convex shape determined by the present invention is not limited to the one-dimensional lenticular lens of the optical sheet of Fig. 1. For example, the two-dimensional concavo-convex shape such as a microlens or a pyramidal prism can be determined by the present invention. Further, the optical sheet in which the uneven shape is determined by the present invention is not limited to the light guide plate and the light diffusing plate, and may be, for example, an optical film for other surface light source devices, Α(}(α^
Glare)膜（磨砂膜）、或者賦予有光擴散性之保護膜。作為 面光源裝置用之光學片材，例如有微透鏡薄膜、雙凸透鏡 薄膜、於前端部帶有弧度之稜鏡片材。作為賦予有擴散性 之保護膜，有反射型偏光薄膜用保護膜、偏光板用保護 膜。 【圖式簡單說明】 圖1係表示光學片材之一實施形態之立體圖。 圖2係表示光學片材之製造方法之—實施形態之模式 品之步驟之一實施 圖3(a)〜(c)係表示成形光學構件試製 形態之放大模式圓。 【主要元件符號說明】 0 光學片材（光學構件、光學構件試製品） 3 側面 5 凸狀部 3 光學片材製造裝置 ^ 壓模 I61653.doc 201235196 52A 擠壓軋輥 52B 擠壓軋輥 52D 預壓軋輥 53 轉印模 53a 凹部 57 樹脂投入口 58 擠壓機 hi 深度 h2 高度 h3 高度 SI 主面 S2 背面 16I653.doc - 12Glare) film (matte film) or a protective film imparted with light diffusibility. Examples of the optical sheet used for the surface light source device include a microlens film, a lenticular film, and a ridge sheet having a curvature at the front end portion. A protective film for a reflective polarizing film and a protective film for a polarizing plate are provided as a protective film for imparting diffusibility. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing an embodiment of an optical sheet. Fig. 2 is a view showing an embodiment of a method for producing an optical sheet according to a mode of the embodiment. Fig. 3 (a) to (c) show an enlarged mode circle of a prototype of a molded optical member. [Explanation of main component symbols] 0 Optical sheet (optical member, optical component prototype) 3 Side 5 convex part 3 Optical sheet manufacturing apparatus ^ Stamper I61653.doc 201235196 52A Extrusion roll 52B Extrusion roll 52D Pre-roll roll 53 Transfer die 53a Recess 57 Resin input port 58 Extruder hi Depth h2 Height h3 Height SI Main face S2 Back 16I653.doc - 12