PROBLEM TO BE SOLVED: To detect the degree of a warpage of a top board at a high detection resolving power by a simple structure while keeping a high supporting rigidity of the top board in a table system which is suitable for, e.g., an X-ray CT photographing, in which the top board for mounting an object is let out in the horizontal direction.SOLUTION: A light receiving position specifying section 125 specifies the light receiving position of a laser beam 600 which changes in response to the warpage of a base 104 by a laser light source 122 being installed on the base 104 which supports the top board 102, and a light detector 124. From the light receiving position, the degree of the warpage of the top board 102 is indirectly detected.COPYRIGHT: (C)2009,JPO&INPIT【課題】対象を載置する天板を水平方向に繰り出す、例えばX線CT撮影に適したテーブルシステムにおいて、天板の支持剛性を高く保ちつつ、簡単な構造で、天板の撓みの程度を高い検出分解能で検出する。【解決手段】受光位置特定部125が、天板102を支持する基台104に設けられたレーザ光源122と光検出器124とにより、基台104の撓みに応じて変化するレーザ光線600の受光位置を特定する。この受光位置に基づいて、天板102の撓みの程度を間接的に検出する。【選択図】図6