Touchpad using piezoelectric effect

Abstract

The present invention relates to a touch panel utilizing the piezoelectric effect, and in particular to a touch panel that can use a piezoelectric film and can be remarkably slim with a metal material, and can accurately and stably recognize long keys, multi-keys, and slides performed by a user. Various touch patterns such as key shifting, and can significantly improve the security level of the touchpad using the piezoelectric effect. Therefore, the present invention provides a touch panel utilizing the piezoelectric effect, which is characterized in that it comprises the following configuration: a touch panel having touch keys; a piezoelectric film disposed on the bottom surface of the touch panel and emitting ultrasonic waves; and The control unit analyzes the displacement of the piezoelectric film and the ultrasonic impedance reflected by the surface of the touch panel and a touch object in contact with the surface to recognize a touch by the user.

Description

technical field [0001] The present invention relates to a touch panel, and more specifically, to a touch panel capable of using a piezoelectric film while being remarkably slim in a metal material, and capable of accurately and stably recognizing long keys, multi-keys, and swipes performed by a user. Various touch patterns such as keys, and a touchpad that utilizes the piezoelectric effect that can significantly improve the level of security. Background technique [0002] As an existing technology related to touch-sensitive switches, a (reflection mode ultrasonic) touch-sensitive switch (refer to US Patent No. 5,673,041) has been developed with the following: a substrate (substrate) with a touch area, a piezoelectric element (piezoelectric element) with electrodes ), a drive means for applying a drive signal to the electrodes, a detection means for providing a detection signal derived from the drive signal, and a discrimination means for providing an output signal. [0003]...

AI Technical Summary

Problems solved by technology

[0006] Therefore, even in the case of preventing the touch area from being easily damaged, improving the reliability of the touch to a certain extent, and gradually increasing the intensity of the touch, the sensitivity of the sensor will not be greatly reduced. On the other hand, the ultrasonic method based on the prior art The touch-sensitive switch has the following fatal disadvantages, that is, touch errors caused by foreign objects such as water or tomato paste

[0007] On the other hand, there is also a problem that in the case of a simple piezoelectric system, it is easy to receive external shocks, vibrations, etc., especially when a piezoelectric element is used for touch recognition, the plate thickness of the metal or the like provided with the touch key If it is thick or the interval between touch keys is narrow, the output value of the piezoelectric element is insufficient, so that accurate and stable touch recognition by the user cannot be guaranteed

[0008] In addition, the prior art piezoelectric touch device using the piezoelectric effect (piezo effect) cannot be directly applied to metals or new materials without additional process, or even if the touch input is performed on a metal plate with a touch key, if If the touch object (object) is slowly released, the displacement value of the piezoelectric element cannot be output correctly.

[0009] Therefore, there are problems as follows: long key (long key) input (key input state is maintained for a certain period of time), multi-key (multi key) input (multi-key input state is performed simultaneously) and wheel slip (wheel slide) cannot be recognized safely. Touch input (use drag (drag) touch and let go of the touch object in a short time)

[0010] Therefore, there is still a problem that when a touch device using the piezoelectric effect (piezo effect) is applied to a metal plate or the like, recognition of long key input and multi key input is limited, and the user can set There are very limited types of security keys such as predetermined passwords, and it is actually difficult to expect a high level of confidentiality

[0011] In addition, conventional piezoelectric touch devices using the piezoelectric effect (piezo effect) cannot be realized in a significantly thinner form when ceramic piezoelectric elements are used, so there is a problem that it is difficult to apply to ultra-thin smartphones and the like.

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