Signal generation circuit and light detecting unit

A light detecting unit comprising:

• a light receiving element configured to receive light and generate a charge;
• a signal generation circuit configured to generate a first signal of which voltage changes;
• and
• a converter that converts a second signal that is based on the charge generated in the light receiving element, into a digital signal on a basis of the first signal, wherein
• the signal generation circuit includes:
• an amplifier including a first input section, a second input section, and an output section;
• a first electric current source configured to supply an electric current on a basis of an output voltage of the output section;
• a first capacitor element configured to hold a voltage;
• a first switch configured to electrically couple the first electric current source and the first capacitor element to each other;
• a second switch configured to electrically couple the first capacitor element and the first input section to each other;
• a second capacitor element configured to hold a voltage;
• a third switch configured to electrically couple the first electric current source and the second capacitor element to each other;
• a fourth switch configured to electrically couple the second capacitor element and the first input section to each other;
• a second electric current source configured to supply an electric current on a basis of the output voltage of the output section;
• and
• a signal output section configured to output the first signal that is based on the electric current supplied by the second electric current source.