Abstract: A glass stress test method includes breaking a glass, analyzing a shape of a crack of a broken portion of the glass in a plan view, finding a breakage origin of the glass based on the shape of the crack in the plan view, analyzing a cross-section of the breakage origin, and calculating a stress of the glass based on a cross-sectional analysis result of the breakage origin. The stress of the glass is calculated as a value proportional to a floor constant defined by a condition of a floor surface disposed when the glass is broken.

Abstract: A liquid crystal device for writing, inputting, and displaying information comprises: a first substrate, a second substrate, and a cell structure sandwiched between the two substrates, defining a plurality of isolated subcells. Means for applying an electric field to drive states of the cholesteric liquid crystal in the subcells is coupled to the electrodes. An electromagnetic sensitive panel is positioned proximately under the surface of the second substrate for receiving an electronic/magnetic signal transmitted by a writing tool. In use, when the tip of the writing tool is forced again and moved around the surface of the first substrate, a true track of the movement of the tip is directly shown on the writing surface, while information of the movement of the tip of the writing tool is sensed by the electromagnetic sensitive panel simultaneously.