Abstract: A beam of a gantry-type stage structure includes an accommodating space defined by a lower plate, an upper plate, a front plate, a rear plate and two lateral plates. A truss unit is disposed in the accommodating space, and includes lower and upper joint members which are respectively disposed on the lower and upper plates, first and second vertical members which extend uprightly from the lower and upper joint members, respectively, and diagonal members each of which extends to interconnect one lower joint member and an adjacent upper joint member to provide the beam with a great structural strength and a lightweight structure.

Abstract: A beam of a gantry-type stage structure includes an accommodating space defined by a lower plate, an upper plate, a front plate, a rear plate and two lateral plates. A truss unit is disposed in the accommodating space, and includes lower and upper joint members which are respectively disposed on the lower and upper plates, first and second vertical members which extend uprightly from the lower and upper joint members, respectively, and diagonal members each of which extends to interconnect one lower joint member and an adjacent upper joint member to provide the beam with a great structural strength and a lightweight structure.