CELLULAR PHONE HAVING FUNCTION FOR REDUCING EFFECT ON SURROUNDINGS DUE TO PHONE CALL SOUND

摘要

PURPOSE: A cellular phone having a function for reducing an effect on surroundings due to a phone call sound is provided to prevent inconvenience of other persons caused by sounds during the phone call, by reducing or removing the phone call sounds transferred to the surroundings, but the phone call sounds being transferred to the cellular phone. CONSTITUTION: A voice amplifier(200) amplifies voice signals when voice of a cellular phone user is applied to the voice amplifier(200) via a microphone(100), and then transmits the amplified voice signals to the cellular phone of the other person via a transmitter(300). The voice amplifier(200) also inputs the amplified voice signals to an inversion and amplification unit(400), which inverts the phase of the inputted signals and amplifies them. The signals from the inversion and amplification unit(400) are output to a speaker(600) via a speaker driver(500).