進行專利分析時,IPC分類的選擇會影響最後結果。像黃楨只研究驅動電路的部份,採用的IPC分類就會比較細。
如果要廣泛地分析LCD廠商專利佈局與產業的演化,則可以參考大西宏一郎提供的IPC分類表:
資料來源:大西 宏一郎, 液晶ディスプレイ産業における知識スピルオーバーと研究開発生産性, 2006
這是平面顯示產業的觀察與分析blog。若您引用本部落格的文章,請註明作者與出處。
上面的大意就是,從陰極出發的帶負電電子到了有機材料區的發射層,而陽極釋放帶正電電洞(失去電子的原子)由有機材料區的傳導層出發。在發射層與傳導層的邊界,電子遇到電洞,產生了光子。
- The battery or power supply of the device containing the OLED applies a voltage across the OLED.
- An electrical current flows from the cathode to the anode through the organic layers (an electrical current is a flow of electrons).
- The cathode gives electrons to the emissive layer of organic molecules.
- The anode removes electrons from the conductive layer of organic molecules. (This is the equivalent to giving electron holes to the conductive layer.)
- At the boundary between the emissive and the conductive layers, electrons find electron holes.
- When an electron finds an electron hole, the electron fills the hole (it falls into an energy level of the atom that's missing an electron).
- When this happens, the electron gives up energy in the form of a photon of light (see How Light Works).
- The OLED emits light.
- The color of the light depends on the type of organic molecule in the emissive layer. Manufacturers place several types of organic films on the same OLED to make color displays.
- The intensity or brightness of the light depends on the amount of electrical current applied: the more current, the brighter the light.