Apparatus for training golf players

Claim 1

In golf training apparatus comprising: (a) a base member having an impact area over which a golfer may swing a golf club to strike a target ball carried in the impact area; (b) a light source arranged to direct light onto the impact area to cause a shadow of the golf club head to fall onto the impact area as the club swings across the area; (c) a plurality of photodevices distributed in said area so as to receive light from said light source and which may be shadowed momentarily during the passage of the club across the impact area; (d) signal processing means for correlating signals received from said photodevices during the passage of the golf club over the impact area to provide data relating to an impact of the club on the target ball, the improvement consisting in that said photodevices include (e) first and second transverse photodevices for the detection of club head direction, said first and second photodevices each comprising: (i) a body enclosing a chamber and having an aperture therein defining a slit, the internal surfaces of the chamber being such that light admitted into the chamber via the slit is reflected in such a manner that a uniform internal light flux is established in the chamber; (ii) a photodetector mounted in said chamber whereby the output of the photodevice in response to the internal light flux of the chamber is linearly proportional to the extent to which the slit is shadowed; (iii) a peak detection circuit to which the output of said photodevices connected, and (iv) an analog-digital converter to which the output of said peak detection circuit is connected and operative to provide a binary number representative of the length of the slit masked, and wherein the slits of said first and second photodevices are located symmetrically on either side of a line tangential to the target ball and at right angles to an ideal path of a golf club head when it impacts the target ball.