Abstract: An optical axis alignment apparatus 10 has a chuck 13 for holding an optical member 14, a chuck 16 for holding an optical member 15, a pushing mechanism, which pushes the chuck 1 to generate a predetermined frictional force between the optical member 14 and the optical member 15, and actuators 18A to 18D. The actuators 18A to 18D have a piezoelectric element 51b which generates an impulsive inertial force by abrupt extension and contraction.

Abstract: An optical axis alignment apparatus 10 has a chuck 13 for holding an optical member 14, a chuck 16 for holding an optical member 15, a pushing mechanism, which pushes the chuck 1 to generate a predetermined frictional force between the optical member 14 and the optical member 15, and actuators 18A to 18D. The actuators 18A to 18D have a piezoelectric element 51b which generates an impulsive inertial force by abrupt extension and contraction.

Abstract: The invention provides a lever displacement enlarging mechanism which is applicable for a positioning apparatus of an optical stage, is provided with bisymmetrical levers enlarging and transmitting a displacing force of an actuator element, and in which the distance between the leading end sides of boundary grooves and outer edges of coupling posts is smaller than that between the trailing end sides thereof and the outer edges and action point hinges are located closer to the axis of symmetry so that the fulcrum hinges and the force point hinges are closer to the outer edges of the coupling posts.

Abstract: A kinetofrictional force testing apparatus has a spindle rotated by a variable speed motor. A load cell is disposed in opposition to a disk coupled to the spindle and includes a test head for the disk, a rotational frequency controlling synthesizer, and a personal computer for general control. The rotational speed of the motor is varied on the basis of clock pulses from the rotational frequency controlling synthesizer associated with the personal computer. The rotational frequency and rotational acceleration/deceleration of the disk coupled to the spindle are digitally controlled by a predetermined program set in the personal computer. The test head is supported by a leaf spring having strain gauges mounted on its lateral surfaces. Frictional forces are measured by the output of the strain gauges.

Abstract: A ferroelectric ceramic composition of a ternary system solid solution represented by the general formula:xPb(Sn.sub..alpha.Sb.sub.1.sub.-.sub..alpha.)O.sub.3 -- yPbTiO.sub.3 -- zPbZrO.sub.3wherein x, y and z are the respective mol fractions of the components, x + y + z = 1.00 and 1/4 .ltoreq. .alpha. .ltoreq. 3/4.