201242668 六、發明說明： 【發明所屬之技術領域】 本發明係關於液晶（LC)塗佈機，其能在塗佈時計算液 晶滴數目的液晶塗佈機。 【先前技術】 平面顯示器（FPDs)包括持續增加的技術，使得影像顯 不器較使用陰極射線管的傳統電視和影像顯示器更輕而且更 薄’而且厚度通常小於10公分（4射）。需要持續更新的 平面顯示器包括液晶顯示器（LCDs)、電漿顯示器、場發射 顯示器（FEDs)、有機發光二極體顯示器（〇LEDs)、表面傳 導電子發射顯示器（SEDs)、奈米發射顯示器（N£Ds)以及 電致發光顯示器（ELDs)。 液晶顯示器（LCD)是由數個彩色或單色的晝素在光源 或是反射板前呈矩陣排列，所組成的薄型平面顯示裝置。液 B曰顯示器因為使用非常小的電力能源而被廣泛地利用。 用於液晶顯示器的液晶面板的製造過程如下。 彩色遽光片和共用電極的圖案先形成於上玻璃基板。薄 膜電晶體（TFT)和晝素電極的圖案則形成在相對於上玻璃 基板的下玻璃基板上。配向層則分別形成在上和下玻璃基板 上。母個配向層都會被摩擦以提供預傾角以及方向，給將形 成於配向層間之液晶層的液晶分子。 接著使用點膠機以形成膠圖案在上和下玻璃基板其中之 201242668 - ’來密封上及下玻璃基板，祿⑽將存在於其間。在此 之後\液晶塗佈機用來塗佈液晶於形成膠圖案的玻璃基板 上接著，卫裝上及下玻璃基板以形成液晶面板。上及下玻 璃基板的組裝成品在切割和則過程中被分成各別的面板。 ，晶塗佈機包括—平台、—塗佈頭部單元，以及一塗佈 頭4單元支撐框架’以支撐塗佈頭部單元^塗佈頭部單元包 括盛裝液晶的注射器、透過其而塗佈液晶的噴嘴，以及幫浦 模組以對液晶施加壓力使其透過喷嘴塗佈。 △在維射嘴和基板之朗定麟辆時，將承載基板的 平台在軸方向上移動’或是將塗佈頭部單元在X軸方向上 ^動，或是在Χ-Υ軸方向上移動兩者，讓液晶塗佈機透過喷 嘴將液晶塗佈在基板上。如此一來，包含在注射器中的液晶 以液滴的形式從喷嘴滴到基板上。當幫浦十的柱體每旋轉 360度，就有一滴液晶液滴從喷嘴滴到基板上。 在塗佈之前，必須要決定在之後的每個面板上形成液晶 二所需的液晶參考量。傳統的液晶塗佈機根據液晶的參考 ^ ’來控條體的旋轉次數以滴m減旋轉的次數 ^將液晶的參考量除以液滴量所得出的。然而，盛裝在注射 器中的液晶中可能存在有氣泡。因此當幫賴組巾的柱體旋 轉度，氣泡就從噴嘴排出。這樣會導致液晶的參考量和 液晶的實際塗佈量之間的誤差。操作員被要求目視檢查液晶 的參考量是否塗制玻璃基板上的每個面板區域。 這樣的目視檢查需要具有大量經驗的操作員以及實驗以 4 201242668 確認準確性。此外，在進行目視檢查時需要中斷液晶塗 操作。 【發明内容】 有鑑於此，本發明的目的之一在於提供一種液晶塗佈 機’可以藉由計算在塗佈過程巾液晶滴的數目來自動檢查是 否塗佈了液晶的參考量。 — 根據本發明的一個目的在於提供一種液晶塗佈機，盆中 包括至少-喷嘴，可相對於基板移動，自其滴下—液晶滴； 一供應單元，用以供應液晶至該喷嘴；以及一計數單元，包 括·一感應器，用以偵測液晶滴從喷嘴滴下；以及一控制單 元’根據來自感應器的資料計算液晶滴的數目以檢查是 際滴下一液晶參考量。 本發明之歧以及其他的目的、獅、方向以及優點， 將藉由隨類於本發_物贿配合職_式而清楚了 解0 【實施方式】 將以本發％的實施解細贿雜參考，並誠圖式舉 第1圖係為說赚據本發明—液晶塗佈機實施例之剖面 如第1圖所示，根據本發明實施例之液晶塗佈機1〇〇， 5 201242668 包括至少一喷嘴111，透過喷嘴111使液晶塗佈在基板ίο上。 噴嘴111可相對於基板移動。噴嘴ill連接到安裝在塗 佈，部單元11G的噴嘴塊⑴。塗佈頭部單元11G係由頭部 支標框架1〇2所支標，並可在一方向上移動。頭部支撐框架 的兩端均固定於液晶塗佈機的主體1〇1，並可在與塗佈頭 邻，7L 110的移動方向垂直的方向上移動。因此安裝在塗佈 頭部單元110的喷嘴U1可相對於基板10移動。仔細地說， 噴嘴111可相對於基板於X和Y方向上移動，以於塗佈時維 持噴嘴111和基板10之間固定的距離。 供應單元120提供喷嘴ill在之後於面板上形成液晶層 所需的液晶參考量。在幫浦模組122中的柱體根據液晶參考 量旋轉，以從喷嘴111滴下液晶至基板的面板區域◎在基板 上有複數個面板區域。在此之後，上及下基板的組裝成品在 切割和裂片過程中被分成各別的面板。 供應單元120包括盛裝液晶的注射器121和幫浦模組 122。幫浦模組122對液晶施加壓力以從喷嘴in滴下液晶 滴。在幫浦模組122中的柱體的旋轉，以開啟以及關閉從注 射器121到喷嘴ill的液晶流體，使得液晶滴可以滴到基板的 面板區域。 供應單元120可包括氣壓供應單元，以提供氣壓以及 閥。氣壓供應單元提供空氣或氣體至注射器121，使液晶滴 從喷嘴111滴下。閥則開啟或關閉從注射器121至喷嘴⑴ 的液晶流體，使得液晶滴可滴到基板之面板區域。供應單元 201242668 120並不限於前述裝置，亦可包括任何可控制液晶流體者。 也可提供兩個或翅喷嘴’明時將液晶參考量塗佈在 大尺寸基板的兩個或多個面板區域上。在面板製程後，上及 下基板的組裝成品在_和裂片過程中被分成各別的面板。 每個面板可應用成筆記型電腦的螢幕、平面顯示器以及LCD 電視。 在塗佈之刖，先決定之後面板上形成液晶層所需的液晶 參考量。接著幫浦模組中的柱體根據液晶參考量旋轉。如此 一來，液晶就以液滴的形式塗佈在面板區域上。然而實際塗 佈在面板區域的液晶量可能少於或多於液晶參考量。這是因 為盛裝在注射器中的液晶有氣泡的存在。也就是當柱體旋轉 時，會排出氣泡而不是液晶。 計數單7G 130決定了液晶參考量是否實際地塗佈到面板 區域上。為了達到這個目的，計數單元13〇計算從喷嘴iη 滴下的液晶滴數目。如此一來，就可以自動決定液晶參考量 是否真正地塗佈到面板區域’而不必中斷塗佈過程以進行目 視檢查。 計數單元130包括感應器丨31以及控制單元141。 感應器131感應從噴嘴1U滴下的液晶滴。如第2圖所 示’感應器131包括發射部132以發射光線，以及接收部133 以接收發射自發射部131的光線。發射部132以及接收部133 延伸到喷嘴111之下，喷嘴111則位於兩者之間，使得從發 201242668 射部132發射的光線可以通過噴嘴U1下方，並到達接收 133 〇 如第3圖所示’發射部132可包括複數個發射頭。如此 一來，從任何方向滴下的任何液晶滴可阻隔發射自複數個發 射頭的任意光線。也就是說，發射自任一個發射頭132a的光 線可以自喷嘴111傾斜滴下的液晶滴所反射。 發射部132係使用填入光纖的塑膠以射出成型所製成。 其中最簡單的形式就是，兩根或多根光纖以規則間隔成列地 δ又置在模具凹槽，接著就蓋起來並注入樹脂。在這個時候， ，根光纖用來當作發射頭的一端，並沒有被樹脂覆蓋。這些 光纖可以規則間隔成行、成列或成行也成列的方式設置在之 後被封閉且注入樹脂的模具凹槽中。在這種情況下，發射頭 係以固定間隔成行、成列或成行也成列的方式排列。 如第4Β圖所示’當自發射部132發射出的光線被液晶 滴反射’使得接收部133無法接收到光線時，感應器131就 感應到液晶滴的滴下。如第4Α圖所示，當自發射部132發 射出的光線沒有被液晶滴反射，使得接收部133可以接收到 光線時’感應器131就感應到沒有液晶滴的滴下。 在發射部132具有複數個發射頭的情況下，當接收部133 沒有接收到所有自發射頭132a所發射的光線時，感應器131 就感應到液晶滴自喷嘴111滴下。 感應器131可以進一步包括蓋子134。蓋子134可以避 201242668 i 發射部132的光線自1 彈起的液日日滴反射。這就可以避免可能重複計算的誤差。- 紐ΪΓ 134在巾央具有—開口咖，且提供在發射部B2 兩個較低端，使得開口 ma的位置剛好在喷 嘴下方。開π 134a夠大以使得液晶滴可以穿過 1 阻擋。蓋子m、發射部132卩及接收部133可以一體U 以形成感顧131。這樣做可以方便地將感應器131和喷嘴 塊112連接，而不需要調整發射部132和接收部133的位置。 控制單元141根據感應器131提供的資料，以計算從喷 嘴111滴下的液晶滴的數目來決定有多少液晶實際被塗佈在 基板的每個面板區域。接著，控制單元141比較液滴的計數 和液滴的參考數，以決定實際塗佈的液晶量是否不合規格。 參考數是每一面板所需滴入的液晶滴的數目。液晶滴的 參考數（RN)是由下列公式所得出：201242668 VI. Description of the Invention: [Technical Field] The present invention relates to a liquid crystal (LC) coater which is capable of calculating a liquid crystal droplet number at the time of coating. [Prior Art] Flat panel displays (FPDs) include an ever-increasing technique that makes image displays lighter and thinner than conventional television and image displays using cathode ray tubes, and typically have a thickness of less than 10 cm (4 shots). Flat panel displays that require continuous updates include liquid crystal displays (LCDs), plasma displays, field emission displays (FEDs), organic light emitting diode displays (〇LEDs), surface conduction electron emission displays (SEDs), and nano-emissive displays (N £Ds) and electroluminescent displays (ELDs). A liquid crystal display (LCD) is a thin flat display device composed of a plurality of colored or monochromatic halogens arranged in a matrix in front of a light source or a reflecting plate. Liquid B曰 displays are widely used because of the use of very small power sources. The manufacturing process of the liquid crystal panel for a liquid crystal display is as follows. The pattern of the color grading sheet and the common electrode is first formed on the upper glass substrate. A pattern of a thin film transistor (TFT) and a halogen electrode is formed on the lower glass substrate with respect to the upper glass substrate. The alignment layers are formed on the upper and lower glass substrates, respectively. The parent alignment layers are rubbed to provide a pretilt angle and direction for the liquid crystal molecules to be formed in the liquid crystal layer between the alignment layers. Next, a glue machine is used to form a glue pattern on the upper and lower glass substrates of the 201242668 - ' to seal the upper and lower glass substrates, and Lu (10) will be present therebetween. After that, the liquid crystal coater is used to coat the liquid crystal on the glass substrate on which the glue pattern is formed, and then the upper and lower glass substrates are mounted to form a liquid crystal panel. The assembled product of the upper and lower glass substrates is divided into individual panels during the cutting process. The crystal coater includes a platform, a coating head unit, and a coating head 4 unit supporting frame to support the coating head unit. The coating head unit includes a syringe containing a liquid crystal and is coated therethrough. The nozzle of the liquid crystal, and the pump module apply pressure to the liquid crystal to pass through the nozzle. △When the lens is fixed on the lens and the substrate, the platform carrying the substrate is moved in the axial direction' or the coating head unit is moved in the X-axis direction or in the Χ-Υ axis direction. Both are moved, and the liquid crystal coater is applied to the substrate through the nozzle. As a result, the liquid crystal contained in the syringe is dropped from the nozzle onto the substrate in the form of droplets. When the cylinder of the pump 10 is rotated 360 degrees, a drop of liquid crystal droplets is dropped from the nozzle onto the substrate. Before coating, it is necessary to determine the liquid crystal reference amount required to form the liquid crystal on each of the subsequent panels. The conventional liquid crystal coater controls the number of rotations of the strip in accordance with the reference of the liquid crystal to reduce the number of rotations by the number of droplets by dividing the reference amount of the liquid crystal by the amount of liquid droplets. However, air bubbles may be present in the liquid crystal contained in the syringe. Therefore, when the column of the tissue is rotated, the bubble is discharged from the nozzle. This causes an error between the reference amount of the liquid crystal and the actual coating amount of the liquid crystal. The operator is required to visually inspect whether the reference amount of the liquid crystal is applied to each panel area on the glass substrate. Such visual inspection requires an operator with extensive experience and the experiment confirms the accuracy with 4 201242668. In addition, it is necessary to interrupt the liquid crystal coating operation when performing a visual inspection. SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to provide a liquid crystal coater that can automatically check whether a reference amount of liquid crystal is applied by calculating the number of liquid crystal droplets in a coating process. - an object according to the invention is to provide a liquid crystal coater comprising at least a nozzle movable relative to the substrate from which droplets are dropped - a liquid crystal droplet; a supply unit for supplying liquid crystal to the nozzle; and a count The unit includes an inductor for detecting drop of the liquid crystal droplet from the nozzle; and a control unit 'calculating the number of liquid crystal droplets based on the data from the sensor to check the liquid crystal reference amount. The differences between the present invention and other purposes, lions, directions, and advantages will be clearly understood by the type of _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing a section of a liquid crystal coater according to the present invention. As shown in FIG. 1, a liquid crystal coater 1〇〇, 5 201242668 according to an embodiment of the present invention includes at least A nozzle 111 passes through the nozzle 111 to apply liquid crystal on the substrate ίο. The nozzle 111 is movable relative to the substrate. The nozzle ill is connected to the nozzle block (1) mounted on the coating unit 110G. The coating head unit 11G is supported by the head support frame 1〇2 and is movable in one direction. Both ends of the head support frame are fixed to the main body 1〇1 of the liquid crystal coater, and are movable in a direction perpendicular to the moving direction of the coating head adjacent to the 7L 110. Therefore, the nozzle U1 mounted on the coating head unit 110 can be moved relative to the substrate 10. In detail, the nozzle 111 is movable in the X and Y directions with respect to the substrate to maintain a fixed distance between the nozzle 111 and the substrate 10 during coating. The supply unit 120 provides the liquid crystal reference amount required for the nozzle ill to form a liquid crystal layer on the panel thereafter. The cylinder in the pump module 122 is rotated according to the liquid crystal reference amount to drop the liquid crystal from the nozzle 111 to the panel region of the substrate. ◎ There are a plurality of panel regions on the substrate. After that, the assembled products of the upper and lower substrates are divided into individual panels during the cutting and splitting process. The supply unit 120 includes a syringe 121 containing a liquid crystal and a pump module 122. The pump module 122 applies pressure to the liquid crystal to drop the liquid crystal droplets from the nozzles. The rotation of the cylinder in the pump module 122 opens and closes the liquid crystal fluid from the injector 121 to the nozzle ill so that the liquid crystal droplets can drip onto the panel area of the substrate. The supply unit 120 can include a pneumatic supply unit to provide air pressure as well as a valve. The air pressure supply unit supplies air or gas to the syringe 121 to drip the liquid crystal droplets from the nozzle 111. The valve then opens or closes the liquid crystal fluid from the injector 121 to the nozzle (1) so that the liquid crystal droplets can drip onto the panel area of the substrate. The supply unit 201242668 120 is not limited to the aforementioned devices, and may include any person who can control the liquid crystal fluid. It is also possible to provide two or fin nozzles. The liquid crystal reference amount is applied to two or more panel regions of the large-sized substrate. After the panel process, the assembled assembly of the upper and lower substrates is divided into individual panels during the _ and splitting process. Each panel can be applied to a notebook screen, flat panel display, and LCD TV. After coating, the liquid crystal reference amount required to form the liquid crystal layer on the rear panel is first determined. Then the cylinder in the pump module rotates according to the liquid crystal reference amount. In this way, the liquid crystal is applied to the panel area in the form of droplets. However, the amount of liquid crystal actually applied to the panel area may be less or more than the liquid crystal reference amount. This is because the liquid crystal contained in the syringe has the presence of air bubbles. That is, when the cylinder is rotated, bubbles are discharged instead of liquid crystal. The counting sheet 7G 130 determines whether or not the liquid crystal reference amount is actually applied to the panel region. To achieve this, the counting unit 13 calculates the number of liquid crystal droplets dropped from the nozzle in. In this way, it is possible to automatically determine whether or not the liquid crystal reference amount is actually applied to the panel area' without interrupting the coating process for visual inspection. The counting unit 130 includes an inductor 丨 31 and a control unit 141. The inductor 131 senses liquid crystal droplets dropped from the nozzle 1U. As shown in Fig. 2, the sensor 131 includes a transmitting portion 132 to emit light, and a receiving portion 133 to receive light emitted from the emitting portion 131. The emitting portion 132 and the receiving portion 133 extend below the nozzle 111, and the nozzle 111 is located therebetween so that the light emitted from the emitting portion 132 of the 201242668 can pass under the nozzle U1 and reach the receiving 133, as shown in Fig. 3. The 'emitter portion 132' can include a plurality of transmit heads. In this way, any liquid crystal droplets dripping from any direction can block any light emitted from a plurality of emitters. That is, the light emitted from any one of the emitters 132a can be reflected from the liquid crystal droplets which are obliquely dropped from the nozzle 111. The emitting portion 132 is made by injection molding using a plastic filled with an optical fiber. The simplest form is that two or more optical fibers are arranged in a regular interval and placed in the groove of the mold, and then covered and injected with resin. At this time, the root fiber is used as the end of the emitter and is not covered by the resin. These fibers may be arranged in rows, columns, or rows and columns in a regular manner and then enclosed and injected into the mold recess of the resin. In this case, the emitting heads are arranged in rows, columns or rows in a fixed interval. As shown in Fig. 4, when the light emitted from the emitting portion 132 is reflected by the liquid crystal droplets so that the receiving portion 133 cannot receive the light, the sensor 131 senses the dropping of the liquid crystal droplets. As shown in Fig. 4, when the light emitted from the emitting portion 132 is not reflected by the liquid crystal droplets, so that the receiving portion 133 can receive the light, the sensor 131 senses that no liquid crystal droplets are dripped. In the case where the transmitting portion 132 has a plurality of transmitting heads, when the receiving portion 133 does not receive all the light emitted from the emitting head 132a, the sensor 131 senses that the liquid crystal droplets drip from the nozzle 111. The sensor 131 may further include a cover 134. The cover 134 can avoid the reflection of the liquid from the 1st bounce of the light of the 201242668 i emission unit 132. This avoids errors that may be repeated. - The New Zealand 134 has an open coffee at the center of the towel and is provided at the lower two ends of the launching portion B2 such that the opening ma is positioned just below the nozzle. The opening π 134a is large enough so that the liquid crystal droplets can pass through the 1 barrier. The cover m, the emitting portion 132A, and the receiving portion 133 may be integrally U to form a look 131. This makes it easy to connect the sensor 131 and the nozzle block 112 without adjusting the positions of the transmitting portion 132 and the receiving portion 133. The control unit 141 determines how much liquid crystal is actually applied to each panel region of the substrate based on the data supplied from the sensor 131 to calculate the number of liquid crystal droplets dropped from the nozzle 111. Next, the control unit 141 compares the count of the liquid droplets with the reference number of the liquid droplets to determine whether or not the actually applied liquid crystal amount is out of specification. The reference number is the number of liquid crystal drops that need to be dropped into each panel. The reference number (RN) of the liquid crystal droplet is obtained by the following formula:
RN=參考量/DA 其中參考量是在每片面板形成液晶層所需的液晶量，而DA 是液滴量。當液滴的計數小於或大於參考數_)，控制單元 141決定液晶的實際塗佈量不合規格。 控制單元141可以使用警告單元（未繪示）來警告操作 員液晶量不合規格。 控制單元141可以藉由比較液晶實際塗佈量和參考量， 201242668 規格。液晶實際塗佈量是將液 ^ ()。纽晶實際_量小於或大 於參考1時，控鮮元⑷決歧晶的實際塗佈科合規^ 控制單元141 控制早元來運作。 控制單元141 剩餘量： 可獨立於控制液晶塗佈機的塗佈操作的主 可以下列公式計算在注射器121中的液晶 ΒΑ (剩餘夏）=TA-(AAxDA) 其中BA是在注射器121中液晶剩餘量，ΤΑ是在注射器121 中的液晶初始總量’而ΑΑ是液晶滴的累計數，DA則是液 滴番。RN = reference amount / DA where the reference amount is the amount of liquid crystal required to form a liquid crystal layer on each of the panels, and DA is the amount of liquid droplets. When the count of the droplets is smaller or larger than the reference number _), the control unit 141 determines that the actual coating amount of the liquid crystal is out of specification. The control unit 141 can use a warning unit (not shown) to warn the operator that the liquid crystal amount is out of specification. The control unit 141 can compare the actual coating amount and the reference amount of the liquid crystal, 201242668 specifications. The actual amount of liquid crystal coating is the liquid ^ (). When the actual amount of the nucleus is less than or greater than the reference 1, the actual coating department of the control unit (4) is in compliance with the control unit 141, and the control unit 141 controls the operation of the early element. Control unit 141 Remaining amount: The liquid crystal ΒΑ in the syringe 121 can be calculated independently of the main control of the coating operation of the liquid crystal coater (remaining summer) = TA - (AAxDA) where BA is the liquid crystal remaining in the syringe 121 The amount, ΤΑ is the initial total amount of liquid crystal in the syringe 121 and ΑΑ is the cumulative number of liquid crystal droplets, and DA is the droplet number.
At ^ 了控制單元141計算在注射器中的液晶剩餘量的功 能，就不需要安裝另外一個設備來確認注射器121中是否裝 有足夠進行塗佈操作的液晶。 控制單元141可在開始塗佈操作之前偵測在喷嘴1U的 尖端是否有液晶滴的存在。感應器131會感應到在喷嘴U1 的尖端有液晶滴的存在。當液晶滴從喷嘴131適當地滴下 時，從發射部132發射的光線從液滴反射一次。然而當液晶 滴停駐在喷嘴111的尖端時’從發射部132發射的光線就會 持續地從停駐在噴嘴lu尖端的液晶滴反射。如此一來，控 制單元141就可以藉由辨識由感應器ι31感應到的兩種不同 的訊號來彳貞測到在噴嘴U1尖端的液晶滴的存在。 201242668 控制單元141可以使用警告單元（ 在喷嘴m的尖端有液晶滴的存在。 元可移到方便操作員移_㈣自單 根據本發明的液晶塗佈機提供 是否不合規格，Μ㈣娜卜繼_^== 液晶麵4的優點。 *辦供關於 本發明可在不偏離所具有的精神或必⑽點的情形下以 不同的形式實施’請注意前述的實施例除非_提到， 限於前述贿㈣任何細節，而是賴廣泛崎論至下列 請^利範圍所定義的精神和範g之巾，因此所有落於申請專 利範圍，或均等者之邊界中的改變或異動都應被之後的 專利範圍所包含。 【圖式簡單說明】 所附圖式是為了提供對本發明進一步的了解，並組成本 說明書的一部分，也說明本發明的實施例而且與詳細描述一 起解釋本發明的原理。在這些圖式中： 第1圖係根據本發明的一液晶塗佈機實施例的剖面圖； .第2圖係第1圖所示喷嘴以及計數單元之透視圖； 第3圖係第2圖感應器之透視圖；以及 第4A圖和第4B圖係第2圖的感應器感應液晶滴自喷嘴 滴下之剖面圖。 201242668 【主要元件符號說明】 10 基板 100 液晶塗佈機 101 主體 102 頭部支撐框架 110 塗佈頭部單元 111 喷嘴 112 喷嘴塊 120 供應單元 121 注射器 122 幫浦模組 130 計數單元 131 感應器 132 發射部 132a 發射頭 133 接收部 134 蓋子 134a 開口 141 控制單元 12At ^ The control unit 141 calculates the function of the remaining amount of liquid crystal in the syringe, so that it is not necessary to install another device to confirm whether or not the liquid crystal in the syringe 121 is sufficiently loaded. The control unit 141 can detect the presence of liquid crystal droplets at the tip end of the nozzle 1U before starting the coating operation. The sensor 131 senses the presence of liquid crystal droplets at the tip end of the nozzle U1. When the liquid crystal droplets are appropriately dropped from the nozzle 131, the light emitted from the emitting portion 132 is reflected once from the droplet. However, when the liquid crystal drops are parked at the tip end of the nozzle 111, the light emitted from the emitting portion 132 is continuously reflected from the liquid crystal droplets parked at the tip end of the nozzle lu. In this way, the control unit 141 can detect the presence of liquid crystal droplets at the tip of the nozzle U1 by recognizing two different signals sensed by the sensor ι31. 201242668 The control unit 141 can use the warning unit (there is the presence of liquid crystal droplets at the tip of the nozzle m. The element can be moved to facilitate the operator to move _(4) from the single liquid crystal coater according to the present invention to provide whether the specification is out of specification, Μ(四)娜卜继_ ^== Advantages of the liquid crystal surface 4. * The present invention can be implemented in different forms without departing from the spirit or the point (10). Please note that the foregoing embodiments are limited to the aforementioned bribes unless mentioned. (4) Any details, but rather the broad sense of the spirit and the scope of the following definitions, and therefore all changes or changes in the scope of the patent application, or the boundaries of the equals should be the scope of the subsequent patents. BRIEF DESCRIPTION OF THE DRAWINGS [0009] The accompanying drawings are intended to provide a further understanding of the invention Wherein: Fig. 1 is a cross-sectional view showing an embodiment of a liquid crystal coater according to the present invention; Fig. 2 is a perspective view of the nozzle and the counting unit shown in Fig. 1; Fig. 2 is a perspective view of the sensor; and Fig. 4A and Fig. 4B are diagrams of the sensor for sensing the drop of the liquid crystal droplet from the nozzle. 201242668 [Description of main components] 10 substrate 100 liquid crystal coater 101 Main body 102 head support frame 110 coating head unit 111 nozzle 112 nozzle block 120 supply unit 121 injector 122 pump module 130 counting unit 131 sensor 132 emitting portion 132a transmitting head 133 receiving portion 134 cover 134a opening 141 control unit 12