Abstract: A workpiece (22) having a periphery is centered using a centering apparatus (20) having a workpiece spindle (24, 28) operable to rotate the workpiece (22) about a rotational axis (26), and a centering head (29). The centering head (29) includes a mount (30) movable in a movement direction lying in a plane (40) perpendicular to the rotational axis (26), and generally along a radial line (38) extending outwardly from the rotational axis (26). A swivel head (32) is pivotably supported on the mount (30) and is pivotable about a pivot axis (46) parallel to the rotational axis (26). The swivel head (32) has a pair of bearings (66) spaced apart along a direction lying generally perpendicular to the movement direction, with the bearing axis of each bearing (46) parallel to the rotational axis (26). A distance measuring device (34) is operable to measure the distance between the periphery of the workpiece (22) and a measurement location on the mount (30).

Abstract: A method and circuit for controlling motors utilizing a multiple-phase sinusoidal signal generator (80) with control inputs (71,72,76) for determining motor (84) speed and direction. The multiphase sinewave generator has a synchronous-digital state machine (70) that provides a plurality of analog signals (1A-12A) having phase-shifted waveforms. A resistive-ring network (30) and instrumentation amplifiers (31) shapes the plurality of analog signals to provide a multiphase set of sinusoidal signals (77). Automatic-motor-control systems modify control-inputs (71,72,76) into the multiphase generator (80) based on feedback (105,86) to control motor (84) speed and direction.

Abstract: The present invention provides a measuring apparatus (10) for centering and determining wedge error of an optical element (12) under test. The measuring apparatus (10) preferably includes a lens holder (16) for supporting the optical element (12) to be tested. The lens holder (16) is rotatably supported on an air bearing (68) having an axis such that the lens holder (16) may be rotated about the axis. A first sensor (18) is located proximate the lens holder (16) for measuring the wedge characteristics of the optical element (12). The first sensor (18) is movable in a horizontal, vertical and rotatable direction such that the first sensor (18) may be positioned to a predetermined distance from the optical element (12) at a preselected angle. A second sensor (20) is located proximate the lens holder (16) for measuring centering characteristics of the optical element (12).

Abstract: In accordance with the teachings of the present invention, a light sensing detector assembly (10) having integral fiber optic light transmission strands (16) is provided. The light sensing detector assembly (10) includes a quadrant detector (12) having a plurality of apertures (14) extending therethrough and a photosensitive surface (20) that generates photocurrents in response to exposure to light. The plurality of fiber optic strands (16) each have a first end (18) and a second end (22). The first ends (18) extend through the plurality of apertures (14) and outwardly from the photosensitive surface (20). A light source (26) projects light onto the second ends (22) of the plurality of fiber optic strands (16) such that the light is transmitted through the plurality of fiber optic strands (16) towards a reflective workpiece (50). The light reflected from the workpiece (50) in turn impinges upon the photosensitive surface (20).

Abstract: A portable lens measuring device (10) comprises a plurality of optical fibers (23) and a lamp (18) for providing light to a common end. The portable lens measuring device (10) includes a sensor (32) for detecting light from the common end through the second arm, the light sensor (32) generating a signal responsive to the amount of light detected, and a lens assembly (25), the lens assembly being connected to the common end and having a fixed focal point. The portable lens measuring device (10) includes a controller (12) for controlling the lens assembly (25), for regulating the lamp and for receiving the signal generated by the detector. The portable lens measuring device (10) also includes a sensor motor (14) for moving the lens assembly (25) across a first and second surfaces of the lens to provide a value of the center thickness of the lens.