Image reading apparatus, electronic device, and control method

An electronic device comprising:

• a generator that Generates a pulse signal;
• a sensor comprising a light projector that projects pulsed light corresponding to the pulse signal and a light receiver disposed so as to face the light projector;
• a peak hold circuit that holds a peak value of a voltage value indicating a light reception amount of the pulsed light in the light receiver;
• and
• a current supply circuit that increases a light projection amount of the pulsed light projected from the light projector by increasing a current supplied to the light projector when the peak value is smaller than a reference value and decreases the light projection amount by decreasing the current when the peak value is larger than the reference value.

A control method of an electronic device, the electronic device comprising:

• a generator that generates a pulse signal;
• a sensor comprising a light projector that projects pulsed light corresponding to the pulse signal and a light receiver disposed so as to face the light projector;
• and
• a peak hold circuit that holds a peak value of a voltage value indicating a light reception amount of the pulsed light in the light receiver,
• the control method comprising the steps of:
• increasing a light projection amount of the pulsed light projected from the light projector when the peak value is smaller than a reference value and decreasing the light projection amount when the peak value is larger than the reference value.