Biological information detection device and chair including biological information detection device

A biological information detection device which is installed in equipment comprising a body support portion which supports a body, and which detects biological information of a user of the equipment, the biological information detection device comprising:

• a detection unit comprising:
• a transmitter which transmits a radio wave toward a part of the body supported by the body support portion;
• and a receiver which receives a reflected wave obtained as the radio wave transmitted by the transmitter and then reflected on a part of the body;
• and
• a detection support portion which forms a part of the body support portion, and which supports a part of the body to which the transmitter transmits the radio wave,
• wherein hardness with respect to a part of the body at the detection support portion is softer than hardness with respect to a part of the body at the body support portion excluding the detection support portion.