| 摘要 |
<p>A signal projecting device wearable on an athlete about to throw a projectile, such as shooting a basketball. The device incorporates a leveling sensor arranged to provide an input signal to the projecting device so that a signal indicative of a body part on which the projecting device is mounted being horizontal with respect to a floor or ground surface. The projecting device may project a generally cruciform light beam of one characteristic, such as color or light pattern, when the horizontal condition is sensed. A second light beam of a different characteristic may be projected when the horizontal condition is not sensed.</p> |
