FIELD OF THE INVENTION This invention relates to golf clubs and more particularly to golf club guidance systems for directing a golf player.

BACKGROUND OF THE INVENTION A major commercial need exists for tools that assist golfers in their game. Thorough testing of the putting strokes of thousands of golfers has shown that nearly all golfers have misaligned putting strokes. Such testing may be conducted by utilizing a device of the type disclosed in U. S. Patent. No. 4,809, 984. Striving to improve their putting game, many golfers have relied upon stroke correcting devices to provide calibrated sight indices, which are designed to compensate for putting stroke misalignments. U. S. Pat. No. 4,174, 839 discloses such a device, which comprises a plurality of angularly spaced lines that are placed on the upper surface of the club head to aid with the alignment of putts on sloped greens.

That device, however, does not attempt to correct any inherent misalignment of a golfer's putting stroke.

A golfer often missing sinking a putt into a putting cup through misalignment of the head of the putter. Club misalignment also can effect a golfer's performance with other types of clubs as well. However, once a person strokes through a golf ball, no way exists to determine if club alignment was proper or improper.

Other persistent problems associated with putting arise because of gradient differentials between the location of the golf ball and the putting cup. When putting, the shortest distance between two points is not always a straight line. Successful putting demands that eye-brain-hand-arm-feet symbioses adjust the orientation of the contact surface of the head of a putter to compensate for terrain and contour differences on the surface of a putting green. Again, no useful means exists for confirming the precise and accurate orientation of the club before stroking in such an environment.

U. S. Patent No. 5,165, 691 to Cook ("Cook") discloses a laser golf club putter assembly, which comprises one or two laser generators mounted on the club head with the

associated power source mounted in the club handle. Cook further discloses parallel lasers beams projected from lasers located on the inner heel portion and outer heel portion of the club head. However, Cook does not disclose lasers located in the club head projecting parallel lasers that outline a golf ball. Parallel laser beams spaced apart at a distance larger than the diameter of a golf ball does not eliminate all error and uncertainty to the exact location to which a ball is aimed.

U. S. Patent No. 5,435, 562 to Stock ("Stock") discloses a club having a laser emitting from the hosel one laser beam perpendicular to the shaft of the club. However, the use of a single laser merely provides a general representation of where a ball is aimed, but does not provide a laser beam outline of a golf ball for maximum accuracy and precision.

U. S. Patent No. 5,725, 439 to Halsey ("Halsey") discloses a golf club laser device that mounts above the face of the golf club, but requires lateral and rotational adjustment to properly align the club. In addition, Halsey discloses a putter having only one laser.

U. S. Patent No. 5, 733, 202 to Vargo ("Vargo") discloses a laser putt training aid that is substantially a golf putter having a laser mounted in the head of the club. However, the putter has a single laser and is not effective in the actual putting of a golf ball. The laser that is mounted in the head would be substantially blocked by a golf ball positioned in front of it.

U. S. Patent No. 6,227, 983 to Yang ("Yang") discloses a golf club head and laser pointer arrangement having a laser mounted in a recessed chamber in the head, where the recessed chamber is offset from the center of the face of the head. However, this arrangement utilizes a single laser, which must be adjusted in various angular positions to aim the putter, lending room for error. In addition, such error is compounded by the use of a single laser for aiming.

In view of the deficiencies in the art as described above a continuing need remains for improved putters and putter teaching tools that can improve a golfer's performance.

SUMMARY OF THE INVENTION Embodiments described herein provide novel and improved golf putting aids and use one or more electronic devices within the putter to aid a golfer in aiming and/or hitting a golf ball accurately and precisely. In one embodiment herein termed"passive club"the golf club putter passively provides direct visual feedback to the user via direct reflection of light from the putter off of the ball and into the eyes of the user. In another embodiment herein termed "smart club"the golf club further comprises optic detection and provides processed

information to the user. The latter embodiment may alert the user in a private manner that avoids embarrassment and may even speak to the user or to others.

In some embodiments of both the"passive club"and"smart club, "the golf club putter comprises a handle; a shaft; and a putting head connected by the shaft to the handle. These features are described next.

The putting head comprises a face having a longitudinal axis and a transverse axis, wherein the longitudinal and the transverse axis are substantially perpendicular to each other.

The face of the putting head defines on a surface a plurality of laser sources, where one of either the longitudinal or transverse axis intersects the laser source, at least one of the laser sources are positioned on one side of the other one of the longitudinal or transverse axis, and the laser sources project two or more laser beams that project onto a golf ball in the desired direction. The putting head is of the type known to one of ordinary skill in the art, including wedge-shaped heads, blade-shaped heads, mallet-shaped heads, and any other shape or style head having a putting face upon which a golf ball may make contact. The laser light projection of the outline of the golf ball provides the most accurate guidance for the direction in which the golf ball is aimed. In an embodiment the phrase"intended ball movement" means a direction that is perpendicular to the face of the putting head hitting surface and which extends along an imaginary line from the center of the hitting surface to the intended target.

In another embodiment, the longitudinal axis is a horizontal axis that intersects the laser sources. In a preferred embodiment, the horizontal axis bisects the laser sources.

In another embodiment, the transverse axis is a vertical axis and at least one laser source is positioned to one side of the vertical axis. The vertical axis may represent the center of a sweet spot of the face of the putting head. In a preferred embodiment, half of the laser sources are positioned to one side of the vertical axis.

In a preferred embodiment, the contact surface of the putting head is substantially perpendicular to the surface on which the user is standing during a putting stroke.

The laser sources comprise one or more lenses and at least one power supply assembly connected to one or more laser beam circuits through one or more switch control assemblies, which are all interconnected by an electrical circuit assembly. The power supply assembly may be operated through a battery member or a solar panel member to supply power directly to the switch control assemblies. The battery may comprise a conventional battery system or a rechargeable battery system well known to those of ordinary skill in the art, including zinc-carbon batteries, alkaline batteries, nickel-cadmium, lead-acid batteries,

nickel-metal hydride batteries, lithium ion batteries, zinc-air batteries, zinc-mercury oxide batteries, silver-zinc batteries, metal chloride batteries and the like. Preferably, the batteries are placed in the handle of the club, which adds weight at this point and may improve the balance and stability of the club.

In a preferred embodiment, a solid state laser, preferably a semiconductor diode emits light. A solid laser is desirable because of its durability in view of repetitive impacts between the contact surface of the golf club head and golf balls.

Lenses, if used are located on the front face of the golf club putter. In a preferred embodiment, the lenses are flush with the outer surface of the front face of the golf club putter.

The laser sources emit highly directional light. The light may be thin focused beams or wider lines. The light may be visible light. In embodiments of the invention termed "passive club"the user directly perceives the movement of a golf ball by visible light reflected from the ball and into the user's eyes. In embodiments of the invention termed "smart club"the club itself may detect reflected light and alert the user. In these latter embodiments the club optionally uses infrared light, and the user may receive private feedback, for example via an earpiece. The smart club may allow a golfer to monitor the golfer's swing without necessarily informing others that an electronic training device is being used. In an embodiment, a vibration or light in the handle alerts the user of positioning information and in another embodiment an auditory or visual signal respectively, is received in an ear piece or glasses worn by the user.

Multiple light sources may be used that emit various visible light colors. In particular, laser sources may emit visible laser light at wavelengths between about 430 nm to about 700 nm are desirable. In a preferred embodiment, the laser sources are red, yellow or green.

Infrared lasers also may be used, and typically may employ wavelengths between 700 nm to 3000 nm, 800 nm to 2500, 850 nm to 1500 nm or 900 nm to 1200 nm.

The distal end of the shaft terminates in a fitting called a hosel, to which the putting head is attached. The shaft may be constructed from materials known to one of ordinary skill in the art, including, but not limited to, steel, wood, graphite, titanium, aluminum, and the like. In another embodiment, the shaft is directly connected to the head without a hosel.

The handle is attached to the proximal end of the shaft and may be a conventional golf club handle, including for example, a handle wrapped with a grip or gripping material, such as leather, natural rubber, synthetic rubber, natural polymer, synthetic polymer, or any other material known to a skilled artisan. In one embodiment a switch is mounted on the handle for

ease of operation. A user activates the switch prior to, during or after a putting stroke. In another embodiment, a switch protrudes through the grip such that the golf player may grip the putter while operating the switch to activate one or more features of the device.

In another embodiment, a switch positioned underneath the grip may be activated by squeezing. In a preferred embodiment, the switch is pressure-sensitive and is activated by squeezing any portion of the grip.

Embodiments of the invention may be used in combination with a target either at the practice site or on a golf course. The target is chosen to maximize chances of sinking the golf ball in a golf hole on a putting green. The target is also chosen taking in to account the topography of the terrain of the putting surface.

Passive Club A passive club according to embodiments of the invention contains visible light sources that emit light from the putter surface in the direction of desired ball travel.

Preferably at least two, more preferably at least three, four, or more than four light sources are used in the putter. Solid state lasers are advantageous light sources.

In an embodiment, a user of the passive golf club putter with a laser guidance system switches on the laser light before putting. The coherent laser light beams transmit from the face of the putting head, where one or more parallel laser light beams can strike a golf ball positioned in front of the putting head, while the remaining laser light beams project unobstructed by the golf ball. In an embodiment the club confirms alignment of the club face with the ball and expected travel path via reflection of the transmitted parallel laser light beams that outline the golf ball and, optionally, grass, in front of the ball, indicating that the user may stroke the ball toward the target. If the user has improperly aligned the club with the target, the user may simply adjust the golf club position until properly aligned.

The process may be repeated until the user is able to properly align the golf club with an intended target. As will be appreciated by those skilled in the art, the greater the distance the user is from the target, the smaller are permissible adjustments to alignment of the club with the target. Thus, a user may improve performance through a wide range of distances from the target. As will also be appreciated by those of ordinary skill in the art, the target may be any item convenient to the user.

In another embodiment the putter face includes a light, preferably solid state laser above the ball height and pointing down from the horizontal. The light, for example may be at the top edge of the putter head surface or held above the putter head surface by a short

stalk or other protuberance of the putter head. The light shines in front of the ball at a slight decline to allow reflection off of the ground at a defined distance in front of the ball. This embodiment can provide at least two advantages. In one advantage, the light visually shows the user the expected ball travel. This guiding light can help determine an optimum putt angle to a putting cup. In another embodiment two or more lights may be used to shine down below the horizontal to illuminate two or more spots in front of the ball. In this case, preferably the lights are mounted vertically with respect to each other above the exact center point of the putter face. For example a red laser may be mounted to shine 3 feet in front of the putter face and a green laser may be mounted to shine 7 feet in front of the putter face.

The user may use the two lights to determine relative or absolute distance as well as direction.

A second advantage of the downward shining light is that the light can be used to indicate vertical positioning of the putter. For example, if the light is mounted to shine 3 feet in front of the ball when the club is held vertically, then if the light is seen closer or further away than 3 feet, the putter is leaning too far forward and rearward respectively. A limitation of this technique is the distorting effect of pressing the putter into the grass. This effect is minimized by the use of one or more other lights. In the example where red and green lights shine 3 and 7 feet in front of a vertical putter, the 3 foot distance will be shortened considerably more than the 7 foot distance if the putter is pressed into the ground. Placing less pressure on the putter will restore the relative spacing. In yet another embodiment this correction is carried out with a light that shines closer to the ground and parallel to the horizon. The light will shine into the grass if the putter is pressed into the grass and the light will decline into the grass if the putter is tilted forward.

Smart Club A smart club according to embodiments of the invention contains one or more visible light and/or infrared light sources that emit light from the putter surface and also detects light that reflects from the ball. In an embodiment where a putter is held in place after hitting a ball, the smart club monitors ball speed, ball direction, direction linearity and/or direction to the putter cup. For example, in one embodiment a golf club monitors ball speed by determining time between reflectance signals from the detector that are obtained from light sources that shine onto two different spots of the expected ball travel.

Another embodiment provides ball deviation information by determining the rate that the ball curves away from a centerline path, via detecting reflectance from light shining onto

one or more left side and one or more right light beams. In yet another embodiment the putter determines whether the putter face is aligned facing a target (such as a hole) with optical feedback. In this last embodiment a mirror, other specialized reflector, or even an independent light source advantageously is positioned at a target such as a putter cup. The smart club detector and circuitry optionally detects the target and determines when the putter face is aligned perpendicular with an imaginary line between the center of the putter face and the target.

Smart Club Coznponents Any surface of the smart club may contain light source (s). In addition to or instead of location at the putter face, as described for the passive club design, the smart club advantageously may have one or more light sources on the handle. The club may have one, two, three, four, five, six, more than six, or more than 10 light sources on the handle, that are pointed at least partially down. In an embodiment the lights on the handle point in the direction of the intended ball movement. In an embodiment at least two light sources direct their light to two or more locations along the direction of the intended ball movement. In an embodiment at least 4 light sources direct their light to four or more locations along the intended ball movement. In an embodiment a light source emits a light signal that is elongated and perpendicular with the direction of the intended ball movement. The configuration of this latter embodiment provides the ability of light to intercept a ball that may stray to the left or right from the intended direction.

The smart club may employ two or more light sources that shine upon a ball and generate reflection signals that may be received at or nearly at the same time. To distinguish between the lights, optic filters may be used. In this case a light filter may block light from a second light source from entering an intended receiver of light from a light source having a different wavelength. Alternatively the light sources may be switched on and off, and the pulsed reflectance light signals matched up to their respective light sources by circuitry or software. In yet a more advantageous method the smart club modulates each light source and demodulates the reflected light signal from a detector to derive signals corresponding to each reflection signal.

The embodiment that uses modulation and demodulation generally will greatly improve signal to noise ratio. By way of example, an infrared laser diode may be driven with a direct current power source having a periodic variable voltage that directly increases and decreases the output light intensity in a sinusoidal pattern of 10,000 hertz. The amplitude

modulated light signal reflects from a golf ball and enters an optical receiver such as a photo diode, photo FET, charge coupled diode, avalanche photo diode or other device. The output of the optical receiver is amplified by a circuit that preferentially responds to 10,000 hertz, eliminating signals of other frequencies. The amplified 10,000 hertz signal drives an output device or undergoes analyzed further analysis along with one or more other signals to determine ball speed, ball direction, ball deviation, ball spin or some other parameter.

In an advantageous embodiment two or more light sources are modulated at differing frequencies and demodulated to produce multiple signals. For example, a first light beam on the left side of the putter face may be intensity modulated at 10,000 hertz, a second light beam to the right of the putter face may be intensity modulated at 15, 000 hertz, and a third infrared light beam may be intensity modulated at 20,000 hertz. Reflection of the 5,000 hertz and 10,000 hertz signals indicate ball travel deviation to the left and right respectively, when the putter is held in place after making a putt.. Perturbations in the 15,000 hertz signal optionally may correspond to the light beam reflecting off of dimples in the ball. The rate of these perturbations indicates ball speed. In an embodiment the infrared light reflection of the ball dimples is enhanced over reflection from non-dimpled surfaces by the use of a paint or transparent material that enhances the mirror effect of the ball surface to infrared light.

Ball. speed also may be inferred from using two or more lights mounted above the ball on top of the putter face or in the putter face. This embodiment can provide an estimate of ball travel distance. Here, both lights shine out from the putter face but are directed below the horizon. The lights can be seen by their reflection from the grass or other surface. One light contacts the surface at one distance away from the putter and another light contacts the surface at another distance. The ball travels through both light beams and the time taken to reflect each beam respectively is used to determine a speed. In an embodiment a transit time is determined using a reflectance threshold (such as a point of maximum reflectance) because the ball reflects during a large portion of its travel. In another embodiment only one light is used in this manner and the club determines the time that the ball left the putter by an impact sensor. In each. case, the club optionally guides the user to hold the club vertically. The club may inform the user of vertical placement through use of another light beam that is parallel to the horizon. Other configurations will be appreciated that involve combinations of light beams located in the putter face and/or putter handle.

A smart club includes at least one light receiver, which generates signal (s) for further processing. The light receiver may detect reflected light such as visible light or infrared light from the ball. In an embodiment the light receiver accepts light at the center of the putter.

Advantageously the light receiver aperture is located above the centerline of the putter face by at least 0.05, 0.1, 0.2, 0.3, 0.5 or more than 0.5 times the diameter of the golf ball. In other embodiments the light receiver is at a corner or other location of the putter face, and in yet other embodiments the light receiver is on the handle. Multiple light receivers also may be used. In an embodiment one receiver is sensitive to infrared light and a second receiver is sensitive to visible light. In another embodiment at least one receiver is sensitive to long wavelength infrared light and another receiver is sensitive to short wavelength infrared light.

The one or more receivers in the smart putter generate signals in response to light received from the ball surface. Advantageously the wavelength and modulation (if used) of the light source (s), golf ball optical characteristics and/or ball coatings are optimized to favor detection of a reflectance or fluorescence signal over background signal (s). For example, an infrared wavelength may be selected to minimize interference from reflectance and/or fluorescence/phosphorescence signals from grass or chemicals used to grow grass on golf courses. Deep infrared light may be absorbed by water and will not work as well with wet putter surfaces. Many embodiments use reflection instead of fluorescence because reflectance signals generally are much stronger in intensity and are detected more readily. In another embodiment the receiver has a large surface area of at least 0.1 square inches, 0.25 square inches, 0.5 square inches, or even at least 1 square inch to maximize collected signal.

Advantageously, for lower noise a large focusing lens of this large area concentrates light onto a much smaller light sensitive photo sensor.

In another embodiment the club further comprises a lens that focuses light reflected from nearby regions (example, less than 2 ball diameters away) from further regions.

Reflectance information may be obtained prior to putter contact with the ball. This information may be used to determine generally, how fast the putter collides with the ball.

This information may be utilized to train the user for a given strength of swing to achieve a given ball roll distance. In yet another embodiment the smart club determines relative terrain difficulty by monitoring how much of a horizontal laser beam is received back. This embodiment requires that the club be held vertically. A smart club according to the latter embodiment optionally includes a tilt sensor to provide this feedback, and/or corrects for this parameter. A skilled artisan readily appreciates further ways for implementing this embodiment.

Sfrzart Lmaging

In yet another embodiment a large two dimensional imaging photo sensor is used to detect characteristics of the golf ball putting experience. As a skilled artisan in the engineering arts readily will appreciate, distance of the ball from the putter surface may be determined by the size of the ball image on the sensor surface. In one embodiment a hit ball moves away from the putter surface and the ball image becomes smaller. An embodiment of the smart club monitors this optical change to determine ball speed. The lens used to image the ball may have a focal length that allows the image of the ball to increase in size at a distance from the putter face. Other relationships between image size and distance, as well as ball speed and change in size may be determined by routine optimization and/or experimentation.

In another embodiment the imaging system detects deviation of the ball from a center line course by the ball image shifting from a center position to the side. Other information similarly may be determined, such as whether the putter stroke is straight. A deviation in image from side to side, for example, indicates shaking of the putter from side to side instead of a clean straight hit. In each case, an algorithm may be implemented in software to detect putter motion from image information. In an embodiment the image has two pixels, a left pixel and a right pixel, and the pixels may be obtained from two discrete light sensors. In another embodiment the image is obtained from at least 4 pixels. Other pixel arrangements readily may be determined based on an analysis of available hardware and costs.

Optical Modifications to the Golf Ball Embodiments of the invention exploit the ability to improve information gathering by optically altering the golf ball surface. In one embodiment the entire ball or portions thereof are coated with a thin film of transparent material such as an oil, a wax, a silicone lubricant or coating used for waterproofing, or other polymer that enhances surface reflectivity.

Advantageously the transparent material is a polymer that forms a film in a thickness that exceeds the wavelength of the light being used. In another embodiment the surface coating preferentially reflects infrared light of greater than 800 nanometers. The phrase "preferentially reflects infrared light of greater than 800 nanometers"means that infrared light between 800 and 2400 nanometers, between 850 and 2000 nanometers or even 900 to 1200 nanometers reflects from the ball surface at a higher intensity than regular visible sunlight between 400 and 800 nanometers. In another embodiment infrared light reflection from the ball surface is increased at least 3 times, 5 times, 10 times or even more than 20

times by the coating. In yet another embodiment the coating includes an infrared blocking substance.

In an embodiment the ball is coated with film in an irregular manner such that light reflects off of one section with greater intensity than light from another area as, for example, described above for determining ball rotational speed. In yet another embodiment the coating comprises a fluorescent or phosphorescent dye. In an embodiment the coating includes a fluorescent dye selected from the group consisting of fluorescein, acridine orange, 6- diamidino-2-phenylindole, Hoechst 33358, cascade yellow, rhodamine, azure, ethidium bromide, thiazole, nile-blue, Al phthalocyanine, Mag-Indole-l, oxazine, BIODIPY, a derivative, or a combination of one or more dyes or dye derivatives. In yet another embodiment one or more reflective, fluorescent or phosphorescent dyes is added to the ball surface in a permanent form such as a paint or paint additive.

In yet another embodiment the golf ball surface comprises retroflective material that preferentially reflects light back from the direction of a light source. U. S. Nos. 5,200, 262; 5,812, 317; 5,976, 669; 5,283, 101; 5,474, 827 the contents of which are included by reference in their entireties, describe representative materials for use in a golf ball surface that can greatly increase signal to noise ratio. These retroflective materials particularly are useful when light source (s) and one or more light detectors are located in the putter head.

Retroflective materials yield particularly good signal to noise ratios because these surfaces preferentially return light that hit them back to the direction from where the light came, rather than scatter in all directions. In an embodiment a retroflective material improves the signal enough to allow fluorescence instead of reflectance due to the increased signal gain. In this latter embodiment a retroflective material includes one or more fluorescent or phosphorescent materials and the receiver advantageously responds to light of longer wavelength than the excitation light.

In an advantageous embodiment a broad beam of light shines onto a ball that has retroflective material in the dimples. Flashes of retroflection from the dimples are used to determine ball speed. In an embodiment the time between adjacent flashes is used to determine how fast a ball rolls using, for example, a look up conversion table, a circuit (hardware conversion), or software computation. Preferably speed is determined by a circuit that may be calibrated at the factory and/or by the user. The output speed signal may be displayed electronically as one or more digits that may be imbedded in the smart club handle.

Generally the user holds the putter on the ground after hitting the ball and the putter takes measurements.

Ball Deviation Detection The hardware and/or software in the smart club processes signals from the receiver and generates an output that indicates one or more conditions. The processed result, for example, may determine which side and to what extent a hit ball deviates from a desired center course to a putting cup. Data processing within the smart club may determine ball speed and/or how rapid a deviation occurs. The processing also may determine relative curvature and distance from the hole or from another object. In some cases the processing may be as simple as determining whether the ball enters or crosses a particular laser beam.

Light or image processing may begin before the putter contacts a golf ball. For example, the club may detect an object placed within the hole or behind the hole and alert the user when the putter contact surface is exactly facing the hole, angled off to the left or to the right. The putter also may determine distance to the hole. This latter processing feature may utilize on or more light sources on the handle and advantageously may use a transmitter, receiver or a simple reflector located at the hole. The smart club optionally includes an ultrasonic transmitter and receiver for determining distance and/or the ball location. In an embodiment some or all of the data processing occurs outside the smart club and data is transferred by an electronic link such as an infrared beam or radio wave. Extensive hardware and software for processing light and ultrasonic signals are known to the skilled artisan, for example in the auto-focus camera arts.

Ball Spin Monitoring In yet another embodiment the smart club determines a relative or absolute rate of ball spin and provides this information to the user. This embodiment of the invention exploits the reflectance properties of the reflective dimpled surface of a golf ball wherein reflection signals from a light signal contains spin information through reflection from individual dimples or regions. In a related embodiment the golf ball has multiple colored (visibly colored or with different infrared reflectance regions) that, upon spinning, provide a varying optical target for reflectance detection. This embodiment allows training and monitoring of putting skills using ball spin, a previously under appreciated parameter, for improving performance. Generally, a golfer has had to look at a ball and watch its speed and/or direction to obtain feedback from his swing. The smart club allows the golfer to additionally receive feedback of the ball's rotation itself. The user can discern insufficient rotation from

ball sliding or excessive rotation from ball spinning from each putt by feedback from the smart club.

Direction Detection with Magnetic Sensors In another embodiment the putter learns an optimum direction to a hole from an optical input such as reflection from a reflective target placed in the putting cup, or by another means. In an embodiment the smart club contains hall effect devices for determining direction with respect to magnetic north and circuitry or software for storing direction information. The user advantageously teaches the smart club the proper direction to a putting cup. In an embodiment the user places the putter handle on the ground in a direct line between the ball and the putter cup. Hall effect sensors within the putter sense the direction of the handle with respect to magnetic north and create a signal corresponding with direction of the putting cup. The club stores the directional information. The user picks up the smart club and prepares to putt. The smart club uses the stored information to determine the proper direction heading for the putter face and may alert the user of an alignment error.

Putting Force Detector In another embodiment the smart putter detects putting force with an accelerometer or vibration detector to help the user practice putts of defined distances. This embodiment can utilize less costly and high quality piezoelectric and other solid state sensors that respond to force by generating an electrical signal or by altering an electronic property of a sensor such as impedance. In an advantageous embodiment an accelerometer sensor is built into the club head and used to monitor timing and impact force between putter and golf ball. In an embodiment a piezoelectric vibration or acceleration sensor film or cable is imbedded in the head or is placed at the head surface. The piezoelectric device generates a voltage signal in response to ball contact. The generated voltage signal is influenced by the amount of stress from the impact. A higher speed collision with the ball generates a higher strength piezoelectric signal. The signal can, for example be compared with a stored value or directly converted into a form to indicate force, and thus expected distance of ball movement.

One or more piezoelectric devices can be imbedded in a club and used to determine not only force of contact but also position of contact. This information is very useful not only for putters but for other clubs such as drivers as well. Accordingly, embodiments of the invention specifically include the use of one or more imbedded piezoelectric devices in clubs such as drivers to monitor one or more parameters such as force of impact and impact

location on the club surface. In an embodiment a driver has one or more piezoelectric devices and reports to the user a relative or absolute force from the collision. In another embodiment the location of contact is reported. In yet another embodiment both are reported.

Such signals, can also, for example be compared with a stored value or directly converted into a form to indicate force in particular units and even to estimate or calculate an expected distance of ball movement.

Piezoelectric devices suitable for this embodiment are very sensitive and can be purchased as plastic polymeric films. A wide range of piezoelectric devices may be used for this embodiment. Examples include catalog numbers ACH-04-08-09, ACH-04-08-05, ACH- 01 and similar devices from Measurement Specialties, Inc. (Valley Forge, Pennsylvania). In an embodiment the user calibrates a circuit to obtain a more accurate force or a desired putt distance. This embodiment may be combined with a single or multiple light putter for enhanced performance in other ways as well. The piezoelectric sensor can be used to determine time of putt, force of putt, and (if multiple sensors are used) putting head location where contact has taken place.

Communication to the user The smart club can communicate with a golfer or would be golfer in various ways.

The club may output one or more visual signals, using, for example, lights or an LCD screen.

The club may inform the user of a misalignment by a vibration, tickle, or shock. In an advantageous embodiment the club provides audio feedback from the club itself or via an infrared or radio link to headphones or to an ear piece. In a particularly useful embodiment for shy golfers, the smart club uses infrared light for determining alignment and notifies the user by a hidden ear piece or vibrator that tells the user if the putter is properly level and/or vertical. By using non visible light and a hidden monitoring system the user may receive feedback from the smart club in privacy. The club may include a recorded speech circuit or speech software and may speak to the user. In an embodiment the club reports to the user whether the club face is parallel to the ground and in another embodiment the club reports whether the face is vertical. In another embodiment the club informs the user that the club cannot locate the ball. In another embodiment suitable for blind users the club reports the direction or an estimated distance of a hit ball.

In an embodiment particularly useful for a golfer who has a learning disability the smart club directly adjusts for alignment errors. In this embodiment the smart club contains one or more motorized mechanisms that move the putting head for better alignment. The

smart club, upon activation, looks for optic alignment with a putting cup or flag, and for example, may rotate or slide the putting head with respect to the hosel in response to a misalignment. This embodiment is particularly useful for golfers who are partially blind.

Embodiments of both passive and smart putters may be used indoors or outdoors.

When used outdoors, the surface on which the user stands may be a contoured putting green.

In many cases the objective may be not to stroke directly through the ball to a target, but to adjust the alignment of the head of the club to compensate for the contours of the putting green. Embodiments allow the user to adjust for variations in ground surface contours.

These and other embodiments will be appreciated from the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of a passive golf club putter with eight laser light sources to aid a golfer in aiming the ball accurately.

Figure 2 is a front view of the lower portion of the golf club putter, particularly the putter head, hosel and distal end of the shaft.

Figure 3 is a top view of the golf club putter, ball and golf hole.

Figure 4 is a fragmentary side view of the golf club putter.

Figure 5 is a fragmentary view of the handle portion of the golf club putter.

Figure 6 is a perspective view of a smart club putter with eight laser light sources and one receiver to aid a golfer in aiming the ball accurately.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the invention are described next in the context of the drawings.

The drawings generally describe a mallet/blade hybrid style putter head with cavity back, although a skilled artisan will recognize that the disclosed methods and structures are useful with other types of golf clubs, e. g. , traditional blade style putters, flange-style blade putters, mallet-style putters and the like. With reference to the drawings, and in particular Figure 1, a novel golf club putter embodying the principals and concepts of the present invention, generally designated by reference number 10, will be described.

The golf club putter 10 is utilized in a conventional manner for golf and, more particularly, utilizes a plurality of laser sources to aid a golfer in aiming a golf ball accurately.

The golf club putter 10 includes a putter head 13, a shaft 16 having a distal end 19 and a proximal end 22 and a handle 23. The distal end 19 of shaft 16 terminates and is affixed to a hosel 25 to which the putter head 13 is attached. Putter head 13 (See also Figure 2) is formed with a ball striking face 28, a weighted heel portion 31, a side wall 32 attached to the weighted heel portion 31, and a plurality of bores 34, through which laser light projects.

Handle 23 may be wrapped with a grip or gripping material made of material known to skilled artisans. A switch 37 is mounted on the handle portion 23 of the golf club putter.

Switch 37 may be a rocker switch, a pressure sensitive switch or other appropriate switch.

Switch 37 protrudes through the grip of handle 23 for ease of operation by the golfer.

Figure 3 is a top view showing golf club putter 10, golf ball 52, golf hole 46 and golf pin 49. Distal end 19 of the shaft is attached to the hosel 25, and hosel 25 is connected to the heel portion 31 of the putter head. The putter head 13 is formed with a ball striking face 28, a

weighted heel portion 31, a side wall 32 attached to the weighted heel portion 31, and a plurality of laser sources 40 located in the vertical head portion 55 of putter head 13. A plurality of parallel laser light beams 43 is transmitted by laser sources 40 perpendicular to club head face 28 of the putter head 13, projecting an outline of golf ball 58. A golfer aims golf ball 52 at its intended target by positioning via rotating putter head 13 on the vertical axis such that outline of golf ball 58 projects to the intended target. In this particular embodiment, the target is the center of golf hole 46.

Figure 4 is a side cross-sectional view of putter head 13, hosel 25 and distal end of shaft 19. One laser source 40 of the plurality of laser sources 40 is shown within inner cavity 61, which is located in vertical head portion 55. Laser source 37 utilized in this embodiment is well known and may be purchased as a unit with housing 64 and with first and second insulated wire leads 67 and 68, which couple first and second opposite polarity electrical potentials from the voltage source to energize the laser source 40. Housing 64 is fits laterally in inner cavity 61 and projects its laser beam 43 through front facing lateral bore 34 within vertical head portion 55. Housing 64 slidably fits into the inner cavity 61 and a threaded cap 71 into the rear access opening 74 of the inner cavity 61 to hold laser source 40 in position.

Putter head 13 is substantially sealed to protect laser source 40 from moisture, dust, dirt and the like. This may be accomplished by suitably mounting, such as being glued, a transparent cover in bore 34 to seal one end of the inner cavity 61. In addition, the opposite end of the inner cavity 61 is sealed by a threaded cap 71 and a doughnut-shaped gasket 75. A clearance hole 77 provides a space and passageway for lead wires 67 and 68, which are routed from the laser source 40, through the hollow inner portion 80 of the vertical head portion 55, the hollow inner portion 83 of the heel portion 31, the inner portion 86 of the hosel 25 and the inner portion 89 of the shaft 16. The putter head 13 is substantially sealed, in which the distal end 19 of the shaft 16 is fastened to the putter head 13 by a hosel glue joint 92 in the interface between the outside diameter of the shaft 16 and the inside diameter of the shaft mounting hole 95.

Inner cavity 61 forms during the molding or casting process in the putter head 13 with sufficient dimensional precision relative to the face 28 such that the laser source 40, when installed in the inner cavity 61, emits a laser aiming beam, that aligns substantially perpendicular to the face without further optical alignment. First wire 67 and second wire 68 rout from laser source 40 through the aforementioned communicating cavities and through the hollow inner portion 89 of the shaft 16 and coupling to a voltage source, which is located and controlled from shaft handle 23.

To complete the electrical circuit from the laser source 40 to the first pole of the voltage source, the first wire lead 67 from the laser source 40 is routed through the shaft 16 to couple to the first pole of the voltage source located in the proximal end of the shaft. If the shaft is fabricated from a non-conductive material, such as a polymer or resin, the second wire lead 68 from the laser source 40 is routed through the shaft to couple to the second pole of the voltage source.

Figure 5 shows a voltage source 98 located in the handle 23. The handle 23 is covered substantially by grip 101, which is used by the golfer to hold the club. Typically, the grip 101 is molded from a resilient flexible material, such as neoprene, silicone rubber or a synthetic polymer well known to one of ordinary skill in the art.

The voltage source 98 consists of at least one battery 104 having a first electrical pole 107 and a second electrical pole 110. A second battery 113 may also be included as part of the voltage source 98. Also, located in the handle 23 adjacent to the voltage source 98 is a switch, generally referred to by reference number 116, having a normally open switch element 119 and a fixed switch element 122. Both elements are mounted on a contact support 125, formed from an insulating material such as plastic, which is affixed to the handle 23 by any one of a number of fastening means, such as a plurality of rivets.

The second electrical pole 110 of the voltage source 98 is coupled to the extension lead 67 through an electrically conductive strip 128 suitably affixed to the handle 23. The conductive strip 128, a thin conductive metallic element of arcuate cross section, is interposed between the outside insulative housings of the batteries 104 and 113 and the inside diameter of the handle 23. The conductive strip 128 electrically couples the second pole 110 of the voltage source 98 by means of a conductive spring member 113 in biased contact between the second electrical pole 110 and the strip 128 to the extension lead 68, which is connected to the conductive strip 128 by a wire clip 131 formed on an end of the conductive strip 128.

If shaft 16 and handle 23 are fabricated from a conductive material, the second electrical pole 110 of the voltage source 98 may be coupled directly to the conductive shaft (not shown) through the conductive spring member 132 held in biased contact between the second electrical pole 110 and the conductive shaft by a grip cap 134. Because laser diode modules are sensitive to electrostatic voltages, it is desirable that the second electrical pole 110, which is electrically connected to the shaft 16 and handle 23 is the negative or ground potential of the typical battery 104. Grip cap 134, preferably is manufactured from the same type of rubber material as grip 101, and is secured by an interference fit within battery access

hole 137 in grip 101. When conductive shaft 16 and handle 23 couple the second electrical pole 110 of the voltage source 98 to laser source 40, the conductive strip 128 is not required and, therefore, not needed for the laser aiming system.

As shown in Figure 5, switch 116 is located in the handle 23 such that the first electrical pole 107 of the voltage source 98 contacts normally open switch element 119.

Deflecting the normally open switch element 119 causes it to contact the fixed switch element 122 and thereby couple it to the extension lead 67 through a switch element 137 to which the extension lead 67 is attached. Closing the normally open switch element 119 turns on the laser aiming beam 43 (Figure 1).

Switch element 119 is located adjacent a shaft access opening 140 through which a grip segment 143 may be deformed by applied finger pressure applied to deflect the switch element 119. A relief groove 146 is formed in the grip 101 to weaken the grip 101 when pushing the grip segment 143 through the shaft access opening 140 with normal finger pressure. Typical golf club grips are molded from rubber-like materials and the relief groove 146 is easily formed into its outside surface. Note that the relief groove 146 does not create an opening in the grip 101 through which moisture or dust may enter into the hollow portion of the handle 23 via the shaft access opening 140.

Batteries 104 and 113 are replaced by means of the battery access hole 137 located in the butt end 149 of the grip 101. An interferance fit between the battery access hole 137 and the grip cap 134 seals the battery access hole 137. The sealing of the voltage source 98, contained within the envelope of the grip 101, is completed by a grip glue joint 152, which seals the interface between the grip 101 and the handle 23.

Figure 6 shows smart club putter 60 including putter head 63, shaft 66 having a distal end 69 and proximal end 62 and handle 63. Distal end 69 of shaft 66 terminates and is affixed to hosel 65, which attaches to putter head 63. Putter head 63 (See also Figure 2) forms with ball striking face 68, weighted heel portion 72, side wall 62 attached to weighted heel portion 72, and plurality of bores 74, through which laser light projects. Light detector 70 is located at a position above the middle point of contact. This club differs primarily from the passive club shown in Figure 1 by the addition of light detector 70 and the associated circuitry which provide added feedback to the user.

Various embodiments have been described. The descriptions are offered by way of illustration and not limitation. Thus, it will be apparent to those skilled in the art that modifications may be made to the invention as described without departing from the scope of the claims set forth below.