AUDIO FREQUENCY DEVICE FOR AUDIBLE EYES OFF MEASUREMENTS

摘要

An electrical to audible signal measurement apparatus comprises an absolute value converter, a voltage to frequency converter, a polarity detector, and a waveform changer. The absolute value converter is capable of converting a bipolar input signal into a unipolar signal. The voltage to frequency converter is connected to the absolute value converter and is capable of generating a frequency signal proportional to the unipolar signal. The polarity detector is capable of identifying a polarity of the bipolar input signal to form an identified polarity. The waveform changer is connected to the voltage to frequency converter and polarity detector and is capable of generating a number of different waveforms in an audio frequency range in response to receiving the frequency signal from the voltage to frequency converter and in response to the identified polarity.