Abstract: A golf club putter is provided with a laser generator positioned in the shaft of the club. The laser generator is activated when a push button is depressed, and emits a beam of light downward, reflecting off a mirror positioned near the clubface and exits through an aperture to illuminate a target spot, thus indicating the direction in which the golf ball will travel. In another embodiment, a light beam splitter is provided to reflect a first portion of the light beam in a horizontal plane to illuminate a target spot, and a second portion of the light beam coaxially of the shaft in a selected pattern that is projected on the ground. The golfer may use this putter both on a practice green or in actual play to improve the alignment of his putter with the hole or other target.

Abstract: Two types of optical liquid level sensor are disclosed. In the first refractive-type (20,65), light is selectively refracted by the particular fluid(s) in a plug recess between primary and secondary detectors (D.sub.1,D.sub.2). The output signal from either detector indicates whether the sensor is above or below the liquid level. The signals of the respective detectors are cross-compared and used to corroborate one another. In the second absorptive-type (100), light at a particular wavelength is passed through a body chamber (86'), which is exposed to the liquid whose level is to be sensed. Such light is selectively absorbed by the liquid. A detector (D) is arranged to measure the intensity of such light as has passed through the chamber, and to indicate the level of liquid in said chamber.