scispace - formally typeset
Patent

Driving method for piezoelectric speaker

Hayase Toru
Reads0
Chats0
TLDR
In this article, a diaphragm is used to reproduce in a wide band area with making even sound pressure frequency characteristic over the whole area of an audio frequency by area-dividing the electrode of a piezoelectric speaker.
Abstract
PURPOSE:To realize the reproducing in a wide band area with making even sound pressure frequency characteristic over the whole area of an audio frequency by area-dividing the electrode of a piezoelectric speaker and driving a diaphragm with inputting a signal having a specified frequency component that is filtered at a filter circuit to each divided electrode area. CONSTITUTION:A diaphragm 11 consists of a sheet of piezoelectric element 12 and an electrode 13 attached on the upper surface of the piezoelectric element 12, and the electrode 13 is area-divided to two area, a large and a small ones, 13a and 13b. And with outputting an amplified signal from an amplifier 14, the signal of all frequency band area that is not filtered is inputted to the small area 13b of the electrode 13, on the other hand, to the large area 13a, only the signal of low frequency component that is filtered at a filter circuit 15 is inputted. Thereby, the area driven with a low frequency is relatively increased and the balance between the low area and the high area of emitting sound pressure is maintained.

read more

Citations
More filters
Patent

Apparatus and method for providing a frequency response for audio signals

TL;DR: In this paper, a moving mass transducer generates sound by displacement of a surface defined by a piezoelectric element, which is displaced in response to an interaction of a first signal with a magnetic field.
Patent

Electroacoustic transducer and display device

TL;DR: In this paper, the authors proposed a plane-type electroacoustic transducer which is thin, obtains sufficient sound volume, and achieves excellent acoustic properties, and to provide a display device.
Patent

Output method of sound signal, speaker system, portable device, and computer program

TL;DR: In this paper, the authors proposed a speaker system for generating an output with big sound pressure without a deterioration in tone quality caused by clip, where attenuation and amplification are performed from the speaker through a speaker amplifier, and signal processing for amplifying a level of a second band which is different from the first band, is carried out according to the amount of attenuation.
Patent

Manufacture of polyester film

TL;DR: In this paper, the authors proposed a method to prevent the sticking between a roll and film and the defect for transferring the surface of ceramic from occurring by a method wherein polyester film is stretched with ceramic rolls, the surface roughness and the width of recessed part of each of which are rationalized.
Patent

Pickup microphone circuit for bone conduction voice signal

TL;DR: In this paper, a high pass filter consisting of a resistor and a piezoelectric element was used to correct a voice signal of hard of hearing and obtain a clear voice signal by using a high-pass filter having a specific frequency characteristic.