Rotation transmitter

A rotation transmitter interconnecting a pair of rotary members that rotate around a common rotation axis, the rotation transmitter comprising:

• a first member, an intermediate member and a second member that are arranged coaxially with the rotation axis, wherein
• the first member has a first bearing surface formed along the rotation axis and a first direction intersecting with the rotation axis,
• the second member has a second bearing surface formed along the rotation axis and a second direction intersecting with the rotation axis and the first direction,
• the intermediate member has a first middle bearing surface that faces the first bearing surface and a second middle bearing surface that faces the second bearing surface,
• a first static-pressure air bearing is formed between the first bearing surface and the first middle bearing surface and a second static-pressure air bearing is formed between the second bearing surface and the second middle bearing surface,
• the rotation transmitter further comprising:
• a first preload device that biases the first bearing surface and the first middle bearing surface in a direction approaching each other;
• and
• a second preload device that biases the second bearing surface and the second middle bearing surface in a direction approaching each other, and
• the first preload device is a first preload magnet that is provided to the first member or the intermediate member and the second preload device is a second preload magnet that is provided to the second member or the intermediate member.