Abstract: A moving body measuring instrument is disclosed which projects, from predetermined locations thereof, a plurality of beams of light at predetermined angles into a same plane, receives, at predetermined locations thereof, the beams reflected from a moving body as it moves to intersect with the beams, calculates parameters of the motion of the moving body in accordance with predetermined operation from timing data of the beams received, and indicates the results of the calculations on an indicator. The moving body has a light reflective member provided thereon which reflects a beam for measurement toward a direction incident thereto irrespective of its incident angle, and substantially same locations are provided at which beams are projected and received.

Abstract: A batting practice trainer includes a laser oscillator placed in a sensor unit configured to resemble a home plate. Three beams are emitted from the sensor unit in a predetermined pattern, so that the height, speed, and angle of elevation of a swinging bat may be calculated from the passage of the bat across the beams. This is accomplished without interferring with the batters' swing or substantially modifying the bat.

Abstract: The height and inclination of a batter's swing plane are measured by a batting practice device shaped like a home plate and including a laser source and photosensors for detecting laser light reflected by the bat when swung over the plate.