Distance measurement apparatus and distance measurement method

A distance measurement method, comprising:

• receiving, by a first light reception section, at least one of reference light or reflection light, wherein
• the reference light is projected from a light projection section,
• the reflection light is based on reflection of light by a measurement target,
• the light is projected from the light projection section,
• the light reception section includes a plurality of photon counting type light reception devices, and
• a first photon counting type light reception device of the plurality of photon counting type light reception devices is connected in parallel with a second photon counting type light reception device of the plurality of photon counting type light reception devices;
• outputting, by the light reception section, a current based on the reception of the at least one of the reference light or the reflection light;
• converting, by a conversion section, the current into a voltage;
• outputting, by the conversion section, the voltage;
• outputting, by an amplification section, an amplification value by amplifying the voltage;
• and
• outputting, by the amplification section based on the amplification value that exceeds a limit value, the limit value as the amplification value;
• and
• measuring, by a measurement section, a timing at which the amplification value reaches a threshold value.