Vertical beam emitting marker for a sports field

Abstract

A marker for a sports field comprising an elongated substantially vertical device for marking a field position associated with a game playable on the sports field using an object that may become airborne. The field position is used to determine compliance of the object when airborne with a rule of the game. The apparatus also comprises a source for emitting an elongated generally vertical beam of electromagnetic radiation adjacent to the device to help mark the field position.

1 . A marker for a sports field comprising:
 an elongated substantially vertical device for marking a field position associated with a game playable on the sports field using an object that may become airborne, said field position being used to determine compliance of the object when airborne with a rule of the game; and   a source for emitting an elongated generally vertical beam of electromagnetic radiation adjacent to the device to help mark said field position.   
   
   
       2 . A marker according to  claim 1  further comprising an electromagnetic radiation detector for detecting electromagnetic radiation generated by said source and reflected by said object when passing through said beam of electromagnetic radiation. 
   
   
       3 . A marker according to  claim 2  further comprising a position detector for determining an object position of said object based on the electromagnetic radiation reflected by said object when passing through said beam of electromagnetic radiation. 
   
   
       4 . A marker according to  claim 3  further comprising a comparator for comparing said determined object position to stored data indicative of the field position to determine compliance of the object when airborne with a rule of the game. 
   
   
       5 . A marker according to  claim 3  further comprising a recorder for recording the object position determined by the position detector. 
   
   
       6 . A marker according to  claim 1  wherein said source is a first source and wherein said marker further comprises a second source for emitting a beam of electromagnetic radiation, the first source emitting electromagnetic radiation as visible light and the second source emitting electromagnetic radiation other than visible light. 
   
   
       7 . A marker according to  claim 1  wherein said source generates only a single beam of electromagnetic radiation, said beam of electromagnetic radiation being a beam of visible light oriented substantially parallel to the device. 
   
   
       8 . A marker according to  claim 1  wherein said elongated substantially vertical device includes a pole with a substantially vertical central axis and an exterior surface that is elongated in a direction along said central axis and that is at least partially defined by a closed curve in a plane substantially perpendicular to said central axis, said source being disposed within a space defined by the closed curve extended in opposed directions along said central axis. 
   
   
       9 . A marker according to  claim 2  wherein said elongated substantially vertical device includes a pole with a substantially vertical central axis and an exterior surface that is elongated in a direction along said central axis and that is at least partially defined by a closed curve in a plane substantially perpendicular to said central axis, said source being disposed within a space defined by the closed curve extended in opposed directions along said central axis. 
   
   
       10 . A marker according to  claim 1  wherein said elongated substantially vertical device includes a substantially vertical pole, said beam of electromagnetic radiation being generated as an extension of said pole. 
   
   
       11 . A marker according to  claim 1  wherein said elongated substantially vertical device includes a substantially vertical pole mounted in a position that is vertically spaced above a surface of the sports field, said source being disposed below said pole and adjacent the surface of the sports field. 
   
   
       12 . A marker according to  claim 1  wherein said elongated substantially vertical device includes a substantially vertical pole, said source being disposed adjacent an upper end of said pole. 
   
   
       13 . A marker according to  claim 1  wherein said elongated substantially vertical device includes a substantially vertical pole mounted in a position that is vertically spaced above a surface of the sports field, said source being disposed adjacent a lower end of said pole. 
   
   
       14 . A marker according to  claim 1  wherein said elongated generally vertical beam of electromagnetic radiation is substantially vertical, upwardly directed, and substantially parallel to said substantially vertical device. 
   
   
       15 . A marker for a sports field comprising:
 a device with an elongated substantially vertical portion for marking a field position associated with a game playable on the sports field using an object that may become airborne, said field position being used to determine compliance of the object when airborne with a rule of the game, said device including a member with an exterior surface that is elongated in one direction and that is defined by a closed curve in a plane substantially perpendicular to said one direction;   a source for emitting a generally vertical beam of electromagnetic radiation adjacent to the device; and   an electromagnetic radiation detector for detecting electromagnetic radiation generated by said source and reflected by said object when passing through said beam of electromagnetic radiation,   said source and said electromagnetic radiation detector being disposed within the exterior surface of said member.   
   
   
       16 . A marker according to  claim 15  wherein said source and said electromagnetic radiation detector are disposed adjacent to each other. 
   
   
       17 . A marker according to  claim 15  further comprising a position detector for determining an object position of said object based on the electromagnetic radiation reflected by said object when passing through said beam of electromagnetic radiation. 
   
   
       18 . A method for marking a field position on a sports field associated with a game playable on the sports field using an object that may become airborne, said field position being used to determine compliance of the object when airborne with a rule of the game, said method comprising the steps of:
 positioning an elongated substantially vertical device to mark said field position; and   emitting an elongated generally vertical beam of electromagnetic radiation adjacent to the device to help mark said field position.   
   
   
       19 . A method according to  claim 18  further comprising the step of detecting electromagnetic radiation generated by said source and reflected by said object when passing through said beam of electromagnetic radiation. 
   
   
       20 . A method according to  claim 19  further comprising the step of determining an object position of said object based on the electromagnetic radiation reflected by said object when passing through said beam of electromagnetic radiation. 
   
   
       21 . A method according to  claim 20  further comprising the step of comparing said determined object position to stored data indicative of the field position to determine compliance of the object when airborne with a rule of the game.