Transparent sheet having a pattern for infrared reflection

摘要

An infrared ray reflection pattern-printed transparent sheet is provided which can be applied to a data input system of a type of handwriting directly on a screen of a display device and provides a coordinate detect means and which is lightweight, low in a cost, readily increased in an area, possible in mass production and excellent in a read performance. It is an infrared ray reflection pattern-printed transparent sheet in which infrared ray reflective transparent patterns are printed on a surface of a transparent substrate and which is disposed oppositely to a front face of a display device. A cross section obtained by cutting the infrared ray reflective transparent patterns printed on the above transparent substrate in a face orthogonal to the above transparent substrate is formed so that it assumes a multilayer structure comprising a fixed repeating cycle when observed under a scanning electron microscope.

主权项

1. An infrared ray reflection pattern-printed transparent sheet in which infrared ray reflective transparent patterns are printed on a surface of a transparent substrate and in which the infrared ray reflection pattern-printed transparent sheet can be disposed oppositely to a front face of a display device capable of displaying images, wherein
an ink constituting the infrared ray reflective transparent patterns contains an infrared ray reflection material, and the infrared ray reflective transparent patterns are patterns in which reflected patterns of an infrared ray can be read by an input terminal capable of irradiation and detection of an infrared ray and in which position information of the input terminal on the infrared ray reflection pattern-printed transparent sheet can be provided; the infrared ray reflection material is a liquid crystal material which has a wavelength selection reflectivity to a wavelength in an infrared region and which assumes a fixed cholesteric structure; when a cross section obtained by cutting the infrared ray reflective transparent patterns in a face orthogonal to the transparent substrate is observed under a scanning microscope, the infrared ray reflective transparent patterns comprise a multilayer structure, wherein the multilayer structure includes a fixed repeating cycle; a tilt angle formed by a helical axis of the liquid crystal material constituting the multilayer structure and a vertical line on of the transparent substrate is distributed in a range of at least 0 to 45°; and wherein the transparent patterns are dot patterns and a cross-sectional form of the dot patterns are a semi-circular outline form, and respective film surfaces of the multilayer structure corresponding to the half cycle of a spiral pitch in the liquid crystal material are curved along the semi-circular outline form.