Object detection system

An object detection system comprising:

• an acoustic wave generator to generate an acoustic wave by generating heat upon energization;
• and
• a processing circuit to perform object detection processing to detect an object in a target space using an acoustic wave from the acoustic wave generator;
• wherein
• the object detection processing includes:
• wave transmission processing in which the acoustic wave generator is controlled to generate a series of acoustic waves of a time-varying frequency at target sound pressures that are associated with a frequency and correspond to the respective acoustic waves;
• and
• determination processing in which a received-wave signal representing an acoustic wave received by a wave receiver to receive an acoustic wave from the target space is acquired from the wave receiver and it is determined whether the object is present in the target space based on the received-wave signal;
• each of the target sound pressures is set, based on frequency characteristics of sensitivity of the wave receiver to an acoustic wave of a predetermined sound pressure, such that sensitivity of the wave receiver to an acoustic wave of the target sound pressure is in a predetermined range including a predetermined value;
• a frequency of the series of acoustic waves varies in a predetermined frequency range;
• and
• the predetermined value is a maximum value of the sensitivity of the wave receiver to an acoustic wave of a predetermined sound pressure in the predetermined frequency range.