A laser based coordinate measuring device measures a position of a remote target. The laser based coordinate measuring device includes a stationary portion, a rotatable portion, and at least a first optical fiber. The stationary portion has at least a first laser radiation source and at least a first optical detector, and the rotatable portion is rotatable with respect to the stationary portion. The first optical fiber system, which optically interconnects the first laser radiation source and the first optical detector with an emission end of the first optical fiber system, has the emission end disposed on the rotatable portion. The emission end emits laser radiation to the remote target and receives laser radiation reflected from the remote target with the emission direction of the laser radiation being controlled according to the rotation of the rotatable portion.

Laser-based coordinate measuring device and laser-based method for measuring coordinates

A coordinate locating device (8) includes an apparatus (10) having first, second, and third members (21, 22, 23) such that the first member (21) is movable on a base (14), the second member (22) is movable on the first member (21) and the third member (23) has a positionable element (30) and is movable on the second member (22). The device (8) also includes a laser transducer system (16) for establishing the locations of a starting point (52) and a first plane (54) through the starting point (52) which is associated with the first members (21), a second plane (58) having a second reference point (59) which is associated with the second member (22), and a third plane (62) having a third reference point (63) which is associated with the third member (23), and establishing the precise three dimensional location of the positionable element (30). Preferably, a plurality of laser beam reflectors are arranged in a preselected pattern on each of the first, second and third members (21, 22, 23) for reflecting a corresponding plurality of laser beams back toward the associated elements mounted on the base, first and second members (14, 21, 22) respectively, so that yaw, pitch and roll movements can be measured in addition to simple X, Y and Z linear displacement between the various moving stages thereof.

Coordinate locating device

The present invention concerns an interferometer for measuring wavelengths using a rotating periscope and a laser of known wavelength The rotating periscope uses parallel reflectors mounted on a rotating platform A beam splitter splits an input beam into two optical paths which reflect off the rotating periscope and back reflectors so that the paths will have a path length difference The beam splitter splits a reference beam from the laser with known wavelength into two reference optical paths which counter-propagate the input beam's optical paths The light is recombined in a beam splitter to form an interference signal and a reference interference signal so that the input beam's wavelength can be determined

Angular michelson interferometer and optical wavemeter based on a rotating periscope

A projection lens is mounted between a movable stage and a stationary holder to project an image of a reticle held by the holder onto a semiconductive wafer held by a chuck mounted on the stage. The stage is movable along orthogonal X and Y axes in a horizontal plane to align different regions of the semiconductive wafer with the projected image of the reticle. First and second movable plane mirrors fixedly mounted on the stage for movement therewith are symmetrically disposed relative to the Y axis in first and second vertical planes intersecting one another at the Y axis. Similarly, first and second stationary plane mirrors fixedly mounted on a housing of the projection lens are disposed parallel to the first and second movable mirrors, respectively. As the stage is moved along the X and Y axes, first and second interferometer systems provide first and second measurement signals indicative of the velocities of the first and second movable mirrors (relative to the first and second stationary mirrors) while they are being moved along first and second measurement paths normal to the first and second movable mirrors, respectively. In response to the difference and the sum of these measurement signals, first and second position control circuits move the stage along precisely orthogonal X and Y axes with the Y axis bisecting the angle between the first and second movable mirrors.

Interferometrically controlled stage with precisely orthogonal axes of motion

A highly accurate force transducer with flanges and flexures to produce uniaxial flexibility and which utilizes a laser with retroreflectors and an interferometer detecting force movements with resolution of a fraction of a wavelength of light, typically 0.0000003 inch. A mechanical amplifier increases resolution, accuracy, and repeatability. Any deviation from uniaxial movement of the flanges/mirrors detected by three other retroreflector/interferometer systems may be stored in a computer and utilized to correct the force measurements.

Laser interferometric single piece force transducer

An optical system for angle measurement by interferometry comprises four retroreflectors arranged in pairs as beam pathlength multipliers, with two adjacent ones of the retroreflectors rigidly mounted and the other adjacent ones mounted for rotation together about a common axis. A beam of electromagnetic energy, for example a laser beam, is directed towards a beam splitter by which means it is split into two secondary beams, one secondary beam being directed to pass back and forth between one pair of the retroreflectors while the other secondary beam is similarly directed by a beam folder to pass back and forth between the other pair of retroreflectors. Both reflected beams are redirected by retroreflectors along similar paths between their respective retroreflectors to the beam splitter where interference between the secondary beams occurs. The angular displacement of the movable retroreflectors is deduced from the distance between their ridges and the number of fringes generated at the beam splitter.

George D Chapman

Papers

Optical system for angle measurement by interferometry