Abstract: A cholesteric liquid crystal writing board, which can display a writing track, includes a cholesteric liquid crystal device, an optical layer, a photo-sensing array and a voltage control circuit. The cholesteric liquid crystal device includes plural liquid crystal control areas. The optical layer has plural optical openings. The photo-sensing array includes plural photo sensors arranged in an array. The photo sensors are disposed corresponding to the optical openings. One of the photo sensors senses a luminous flux change and generates an erasing signal accordingly. The voltage control circuit receives the erasing signal and outputs a voltage signal accordingly to the liquid crystal control areas corresponding to the photo sensors having the luminous flux change, such that a part or all of cholesteric liquid crystals corresponding to the liquid crystal control areas are morphologically changed so as to clear a part or all of the writing trace.

Abstract: A cholesteric liquid crystal writing board comprises a cholesteric liquid crystal device, a photo-sensing array layer and a mode control unit. The photo-sensing array layer is disposed at one side of the light-emitting surface of the cholesteric liquid crystal device. The photo-sensing array layer comprises a plurality of gate control lines and a plurality of mode control lines. The mode control unit comprises a main control circuitry and a plurality of mode switches coupled to the main control circuitry. Each mode switch is coupled to one of the mode control lines correspondingly. The gate control lines intersect with the mode control lines so as to define a plurality of light sensing areas arranged in an array. Each light sensing area has a switch element and a light-sensing element. The main control circuitry controls each mode switch to be switched between a voltage output mode and a voltage write mode.

Abstract: A cholesteric liquid crystal writing board comprises a cholesteric liquid crystal device, a photo-sensing array layer and a mode control unit. The photo-sensing array layer is disposed at one side of the light-emitting surface of the cholesteric liquid crystal device. The photo-sensing array layer comprises a plurality of gate control lines and a plurality of mode control lines. The mode control unit comprises a main control circuitry and a plurality of mode switches coupled to the main control circuitry. Each mode switch is coupled to one of the mode control lines correspondingly. The gate control lines intersect with the mode control lines so as to define a plurality of light sensing areas arranged in an array. Each light sensing area has a switch element and a light-sensing element. The main control circuitry controls each mode switch to be switched between a voltage output mode and a voltage write mode.

Abstract: A cholesteric liquid crystal writing board, which can display a writing track, includes a cholesteric liquid crystal device, an optical layer, a photo-sensing array and a voltage control circuit. The cholesteric liquid crystal device includes plural liquid crystal control areas. The optical layer has plural optical openings. The photo-sensing array includes plural photo sensors arranged in an array. The photo sensors are disposed corresponding to the optical openings. One of the photo sensors senses a luminous flux change and generates an erasing signal accordingly. The voltage control circuit receives the erasing signal and outputs a voltage signal accordingly to the liquid crystal control areas corresponding to the photo sensors having the luminous flux change, such that a part or all of cholesteric liquid crystals corresponding to the liquid crystal control areas are morphologically changed so as to clear a part or all of the writing trace.

Abstract: A cholesteric liquid crystal writing board can display a writing track, and comprises a cholesteric liquid crystal device, a photo-sensing array layer, a sensing-signal processing circuitry and a voltage control circuitry. The cholesteric liquid crystal device comprises a plurality of liquid crystal control areas. The photo-sensing array layer comprises a plurality of photo-sensing dot-areas arranged in an array, a photo-sensing element of the photo-sensing dot-area senses a luminous flux change and generates a sensing signal. The sensing-signal processing circuitry receives the sensing signal and accordingly outputs position data of the photo-sensing element in the photo-sensing array layer.

Abstract: A cholesteric liquid crystal writing board comprises a cholesteric liquid crystal device, a photo-sensing array layer and a sensing-signal processing circuitry. The cholesteric liquid crystal device comprises a cholesteric liquid crystal layer, and has a light-entering surface and a light-emitting surface opposite to the light-entering surface. The photo-sensing array layer comprises a plurality of photo-sensing elements arranged in an array. The photo-sensing array layer is disposed on one side of the light-emitting surface of the cholesteric liquid crystal device. When at least a portion of the cholesteric liquid crystal layer is morphologically changed due to a pressure caused by a press to generate a luminous flux change, one of the photo-sensing elements of the photo-sensing array layer senses the luminous flux change and generates a sensing signal accordingly.

Abstract: A smart flexile smart curtain film is disclosed, a light transparency for the smart curtain film can be adjusted according to a voltage applied thereon. One of the embodiment shows that the smart curtain film is designed normal dark, and the transparency is related to the voltage applied. The greater voltage is applied the more transparent the smart curtain film displays. The smart curtain film is adaptive to be attached onto a surface of a window glass to form a smart window glass. During daytime, a person can adjust the transparency of the smart curtain to block some light beams from entering the room; and vice versa, during nighttime, a person can adjust the transparency of the smart curtain to block some light beams from exiting the room to keep one's privacy.

Abstract: A barcode reading device for reading a barcode includes a case, a transmissive light-guiding element, an image capturing module, a light source and a light control element. The case has an opening. The transmissive light-guiding element is disposed adjacent to the opening and has a first surface, a second surface and a connecting surface for connecting the first surface and the second surface. The image capturing module is disposed in the case and captures an image of the barcode through the second surface and the first surface. The light source emits a light beam to the connecting surface. The light control element controls the ON/OFF of the light source.