Abstract: Provided is a reference point indicating apparatus comprising at least two link plates, a slide slit formed in each link plate, an indicator configured to be slidable along each slide slit and to be provided at an intersection of a center line of each slide slit, and at least three leg portions configured to be provided on the same circumference centered on the indicator, wherein the indicator is configured to be located on an intersection of a perpendicular bisector of each straight line connecting centers of leg portions adjacent to each other, the leg portions are configured to be contactable with an object 3 by sliding the indicator, the indicator is configured to indicate a reference point of the object in a state where each leg portion is in contact with the object.

Abstract: Provided is a reference point indicating apparatus, which is comprises an equilateral parallelogram being formed with rotatable link points, contacts provided at tips of extending portions obtained by extending respective sides of the equilateral parallelogram, a link plate for linking between middle points of one set of opposing sides of the equilateral parallelogram, and an indicator provided on the link plate, wherein the contacts are capable of abutting on an object by expansion and contraction of the equilateral parallelogram, wherein the indicator is configured to indicate a reference point of the object in a state where the contacts abut on the object.

Abstract: A target support tool includes: a base member including a first arm and a second arm connectable to each other to form a bent therebetween; a magnetic support part at least on the first arm; and a retroreflector at the bent of the base member.