Detection device

A detection device comprising:

• a housing having a ring shape;
• a sensor substrate provided in the housing and curved along the shape of the housing;
• a first optical sensor and a second optical sensor provided to the sensor substrate;
• a light source disposed in the housing;
• and
• a plurality of wiring lines coupling each of the first optical sensor and the second optical sensor to a terminal part provided to the sensor substrate, wherein
• the sensor substrate has a first side extending in a first direction, a second side parallel to the first side, and an opening formed between the first side and the second side when the sensor substrate is developed into a flat shape,
• a first width of the sensor substrate between the first side and an outer periphery of the opening facing the first side is larger than a second width of the sensor substrate between the second side and an outer periphery of the opening facing the second side,
• the opening is formed between the first optical sensor and the second optical sensor in the first direction, and
• the light source is disposed in a region overlapping the opening.