Patent ID: 8178829

Claim:
A system comprising: a first and second laser; a first and second detector; a first end effector of a vacuum robotic handler, the vacuum robotic handler positioned within a vacuum chamber and the first end effector having a first pair of optical couplers, one of the optical couplers being positioned to receive light from the first laser across a vacuum gap and the one of the optical couplers being configured to couple the light from the first laser to a first source fiber that directs the light across a first workpiece support plane of the first end effector, and another one of the optical couplers being positioned to transmit light to the first detector across the vacuum gap and the another one of the optical couplers being configured to couple light from a first target fiber, that has a receiving end positioned on an opposing side of the first workpiece support plane from the first source fiber and oriented to receive light therefrom, to the first detector so that placement of a workpiece on the first end effector in the first workpiece support plane is detected; and a second end effector of the vacuum robotic handler, the second end effector having a second pair of optical couplers, one of the optical couplers being positioned to receive light from the second laser across the vacuum gap and the one of the optical couplers being configured to couple the light from the second laser to a second source fiber that directs the light across a second workpiece support plane of the second end effector, and another one of the optical couplers being positioned to transmit light to the second detector across the vacuum gap and the another one of the optical couplers being configured to couple light from a second target fiber, that has a receiving end positioned on an opposing side of the second workpiece support plane from the second source fiber and oriented to receive light therefrom, to the second detector so that placement of a workpiece on the second end effector in the second workpiece support plane is detected.