Vibration detector, wearable device, and piping inspection apparatus

A vibration detector comprising:

• a diaphragm including a fixed end forming a line segment extending in a first direction;
• and
• a support portion supporting the diaphragm at the fixed end to allow the diaphragm to vibrate,
• wherein a width of the diaphragm in the first direction is maximum at a position farther from the fixed end than a midpoint of a line segment shortest among line segments between the fixed end and an outer periphery of the diaphragm in a second direction orthogonal to the first direction.

A vibration detector comprising:

• a cantilever beam including:
• a support portion;
• and
• a diaphragm including:
• a fixed end fixed to the support portion;
• and
• a tip end farther from the fixed end in a first direction, the tip end vibratile in a second direction intersecting the first direction,
• the diaphragm having a part having a width in a third direction intersecting the first direction and the second direction, and
• the width of the part continuously increasing from the fixed end toward the tip end in the first direction.