In the game of tennis, the portions are defined by the court markings, however, in the game of golf there are no specific markings as such between the portions which take the form of greens, bunkers, fairways and HO roughs. Although most easily adaptable to golf, the present invention is not restricted thereto and is also applicable to croquet, for example.

TECHNICAL FIELD Such outdoor games are played during daylight 15 hours and although some games such as tennis are played on ^" court supplied with artificial lighting, this is not always practical or economic. As a consequence, such games have, by and large, been restricted to the daylight hours. It is the task of the present invention to 20 increase the number of hours during which such games can be played in order to obtain a better utilization of the relatively expensive playing area facilities.

BACKGROUND ART It is known in golf to attempt to extend the Z5 hours of playing from daylight into twilight by the use of a golf ball which is luminescent. For example, golf balls are known which are provided with a coating which is impregnated with a phosphor.. Accordingly, such a ball is visible even in late twilight and can to some 20. extent be "charged" for short periods of time by illuminating the ball with a flashlight.

It is also known to use artificial light sources which chemically generate light, such sources being sold under the registered trade mark CYALUME of American S- Cyanamid Company of Bound Brook N.J. U.S.A. Such ^* sources comprise a stick of two chemical materials separated

- 2 - by a frangible portion which, after being subjected to a predetermined bending, breaks allowing the two chemicals to mix thereby emitting light. Such light sources have been used as a means of illuminating greens and fairways

•2 without the expense of electric lighting. The result is generally speaking unsatisfactorily. It is also known to use a golf ball (manufactured by PICK POINT SPORTS of Florida, USA) with a stick or rod of this material inserted into the centre, also for twilight golf, however,

Id this ball suffers from the disadvantage that it does not behave mechanically or aerodynamically like a conventional golf ball.

All of the above arrangements suffer from the disadvantage that the extended playing time available

-E is relatively short being limited, at best, to several hours of twilight in high latitude countries. Where the golf course is located close to the equator, the period of twilight is much shorter and therefore such stratagems are less successful commercially. f It "is the object of the present invention to provide a means whereby expensive facilities such as golf courses, tennis courses and the like can be utilized during night time without the high capital costs, and high power consumption rates, of artificial lighting, x- SUMMARY OF THE INVENTION

According to a first aspect of the present invention there is disclosed a playing area for night time golf, tennis and like games, said area comprising a playing surface of synthetic or natural grass, said playing surface C being divided into portions by marking strips defining the limits of said portions, wherein said marking strips are made from, or include a luminescent material and are substantially flush with said playing surface to substantially form a continuum therewith. ^τ r According to another aspect of the present invention there is disclosed a method of playing at night time, a game such as golf, tennis or the like on a playing

area as described above with fluorescent marking strips and including at least one ultraviolet light source, said method comprising the steps of using a ball made from, or including, a luminescent material and energizing said ultraviolet light source(s).

According to a still further aspect of the present invention there is disclosed a golf kit for night time golf, said kit comprising at least one ball made from, or including, a luminescent material, at least one club having a luminescent material applied to, or associated with, at least the head of said club, and at least one tee made from, or including, a luminescent material .

According to a still further aspect of present invention there is disclosed luminescent synthetic grass. Preferably the luminescence is caused by fluorescence in which light is emitted as a result of the material being irradiated with, for example, ultraviolet light. However, the luminescence can also be due to phosphorescent which is essentially chemical in origin.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of present invention will now be described with reference to the drawings in which:

Fig. 1 is a schematic perspective view of one hole of a golf course,

Fig. 2 is a cross-sectional view taken along the line 11-11 of Fig. 1,

Fig. 3 is a perspective view of a golf club of the preferred embodiment,

Fig. 4 is a perspective view of a golf tee and golf ball of the preferred embodiment,

Fig. 5 is a schematic longitudinal section through a golf ball cleaning and irradiating device in accordance with the present invention, and

Fig. 6 is a schematic perspective view of an alternative golf ball irradiating device, part of the exterior being cut away to reveal the interior.

BEST METHOD OF CARRYING OUT THE INVENTION Turning now to Figs. 1 and 2, in Fig. 1 a single hole of a multi-hole golf course is illustrated. The hole 1 is provided with a marker flag 2 and is normally ϊ_ centrally located on a green 3. Located adjacent the green 3 are three bunkers 4. The green 3 is approached by a fairway 5 to either side of which is located a rough 6. At the far end of the fairway 5 is a teeing-off area 7. At various locations around the playing area

10 are located ultraviolet light sources 8 which are preferable 400W mercury vapour gas discharge lamps which include WOODS glass as a filtering medium. Such gas discharge lamps are manufactured by IWASAKI ELECTRIC of Japan.

It will be apparent from Fig. 1 that the various 5 portions of the playing surface, such as the green 3 and fairway 5 are separated from each other by marking strips 10. These are shown in detail in Fig. 2 and comprise a strip of synthetic grass having a backing member 11 typically formed from rubber fabric, and a number of 0 tufts 12 formed from a plastics material such as polypropylene. In accordance with the preferred embodiment the polypropylene of which the tufts 12 are manufactured is impregnated with a luminescent material . This material is fluorescent when irradiated with 5 ultraviolet light. Alternatively, the luminescent material can be coated onto the tufts 12. In addition, the tufts 12 are preferably green in colour so as to not be unduly obtrusive during the daylight hours.

As seen in Fig. 2, the marking strip 10 is located Q within a trench 13 formed in the grass 14 of the golf course. Both the strip 10 and the trench 13 are typically one inch (2 cms) wide and only a fraction of this distance deep. In order to secure the backing strip in position, loose sand 15 is sprinkled between the tufts 12 in order 5 to hold the backing member 11 into place by the weight of the sand 15. The use of sand to hold down synthetic

grass is well known. It will be appreciated that the height of the tufts 12 corresponds approximately to the height of the blades of grass at 14 so that the marking strip 10 and grass 14 are essentially flush thereby 5-, ₍ providing a continuous playing surface.

Turning now to Figs. 3 and 4, a golf club 20 for use with the golf course of Figs. 1 and 2 is illustrated in Fig. 3. The golf club 20 is substantially conventional save for a thin strip of luminescent 10 (preferably fluorescent) adhesive backed tape 21 which is applied to the head 22 and shaft 23 of the club 20. The tape 21 is arranged to form a line substantially parallel to the front face 24 of the club 20.

As seen in Fig. 4, a golf ball 31 and tee 32 I_5 of substantially conventional appearance are provided, however, the exterior coating material of the golf ball 1, and the plastics material from which the tee 32, are formed are preferably impregnated with phosphorescent material in order to render the golf ball ^' 3 and tee 32 20. luminescent.

Using the apparatus of Figs. 1,3 and 4, at night time when there is no light available from the sun, the UV light sources 8 can be energized and thereby irradiate the golf course with a low background level of ultra 25- violet light. This is harmless to humans and animals but results in the marking strips 10 glowing due to their fluorescent character, thereby making immediately visible the boundaries of the green 3, fairway 5, and so on. As a result, golf can be played using the club 20 and 3Q_ ball 31 since a player is able to see the ball 31, the tee 32 upon which the ball rests, the club 20, the fairway 5 and the green 3. After the ball 31 has been hit from the teeing-off area 7, the ball can be easily found on the fairway 5 or in the rough 6 because the ball 31 is 3.5: itself luminous. This enables golf to be played at night without the need for expensive artificial lighting. The number of light sources 8 and the energy they consume

is very low, since only a low background level of radiation is required to produce the necessary 1 uminescence.

In addition, a spectacular night time spectator sport is created since the swinging of the club 20 and the flight of the ball 31 provide a pleasing self- illuminated spectacle.

It is desirable for the luminous golf ball 31 to be kept free of dirt which would otherwise reduce the intensity of the light emitted from the ball 31. It is also desirable for the ball 31 to be strongly irradiated with ultraviolet light at regular intervals so as to maintain at a high level the intensity of the light emitted from the ball 31. Both these ends can be simultaneously achieved in accordance with the apparatus of Fig. 5 which is similar to a conventional golf ball washing apparatus. The irradiating washer 40 comprises a generally cylindrical housing 41 having an interior partition 42 which is waterproof, but transparent to ultraviolet light. The partition 42 divides the housing 41 into two enclosures 43 and 44. Within enclosure 44 is located a source of ultraviolet radiation in the form of bulb 45.

Within the other enclosure 43 is located a grooved roller 46 which is rotatable by means of a crank 47. The enclosure 43 contains water 48 and is accessible via lid 49 and opening 50 which permits a golf ball 31 to be placed within, and removed from the enclosure 43. Rotation of the crank 47 repeatedly passes the ball 31 through the water 48 thereby washing same, whilst the ball 31 is simultaneously irradiated with ultraviolet 1 ight from the bulb 45.

An alternative irradiating device is illustrated in Fig. 6 and comprises a generally rectangular box 60 within which is located a bulb 61 and a spirally arranged hollow tube 62 of material which is transparent to

ultraviolet light emitted by the bulb 61. The tube 62 has an inlet 63 an outlet 64. A golf ball 31 (not illustrated in Fig.6) is irradiated by energizing the

\ bulb 61, placing the ball in the inlet 63 and allowing

5 it to roll down the tube 62 and out the outlet 64.

Preferably the interior of the housing 41 and box 60 are reflective.

The foregoing described only some embodiments of the present invention and modifications, obvious

IQ to those skilled in the art, can be made thereto without departing from the scope of the present invention. For example, it is feasible to make the entire green 3 of luminescent artificial grass since the increased usage of the golf course may result in natural grass

15 greens being unable to withstand the traffic. It is also desirable that the marking strips 10 surrounding the greens 3 be a different colour from those surrounding bunkers 4, or fairways 5 in order to "colour code" the various portions of the playing surface. Rather than 0 a strip 21 of luminescent material being provided on the club 20, the entire surface of the club can be luminescent. The club can be painted with, or fabricated from, luminescent material .

The foregoing relates mainly to golf. For tennis, 5- for example, the marking strips and net can be fluroescent and the ball phosphorescent. The court is illuminated with low level ultraviolet radiation. Adaption of the present invention to other sports will be apparent to persons skilled in those sports. 0

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