What is claimed is:
1. A Group III nitride compound semiconductor light-emitting element comprising:
a substrate;
a light-emitting layer made of a Group III nitride compound semiconductor; and
at least one photo-excited semiconductor layer made of a Group III nitride compound semiconductor and excited by light emitted from said light-emitting layer to thereby emit light at a wavelength longer than that of said light emitted from said light-emitting layer.
2. A Group III nitride compound semiconductor light-emitting element according to claim 1, wherein said photo-excited semiconductor layer is doped with impurities.
3. A Group III nitride compound semiconductor light-emitting element according to claim 2, wherein said photo-excited semiconductor layer is doped with at least one member selected from the group consisting of silicon, sulfur, selenium, tellurium, germanium, carbon, and oxygen.
4. A Group III nitride compound semiconductor light-emitting element according to claim 1, wherein band gap energy of said photo-excited semiconductor layer is smaller than that of said light-emitting layer.
5. A Group III nitride compound semiconductor light-emitting element according to claim 1, wherein said photo-excited semiconductor layer is made of In AlyGa1-x-yN (0x1, 0y1, 0xy1, yx) doped with n-type impurities.
6. A Group III nitride compound semiconductor light-emitting element according to any one of claims 1 through 4, wherein said photo-excited semiconductor layer is made of InaGa1-aN (0a<1) doped with n-type impurities.
7. A Group III nitride compound semiconductor light-emitting element according to claim 1, wherein said photo-excited semiconductor layer contains at least one fluorescent substance.
8. A Group III nitride compound semiconductor light-emitting element according to claim 7, wherein said fluorescent substance is selected from rare-earth elements.
9. A Group III nitride compound semiconductor light-emitting element according to claim 1, wherein a plurality of photo-excited semiconductor layers are provided as said at least one photo-excite semiconductor layer.
10. A Group III nitride compound semiconductor light-emitting element according to claim 9, wherein said plurality of photo-excited semiconductor layers are constituted by an alternate laminate of layers different in composition.
11. A Group III nitride compound semiconductor light-emitting element according to claim 9, wherein said plurality of photo-excited semiconductor layers are excited by said light emitted from said light-emitting layer to thereby emit a plurality of kinds of light at different wavelengths respectively.
12. A Group III nitride compound semiconductor light-emitting element according to claim 1, wherein said light-emitting layer emits at least two kinds of light exhibiting emission peaks at different wavelengths respectively.
13. A Group III nitride compound semiconductor light-emitting element according to claim 12, wherein said light-emitting layer emits light in a visible region and light in an ultraviolet region exhibiting a peak emission wavelength in a wavelength range of not longer than 400 nm.
14. A Group III nitride compound semiconductor light-emitting element according to claim 1, further comprising a layer containing at least one fluorescent substance.
15. A Group III nitride compound semiconductor light-emitting element according to claim 1, wherein white light is radiated out.
16. A Group III nitride compound semiconductor light-emitting element comprising:
a substrate;
a light-emitting layer made of a group III nitride compound semiconductor; and
a Group III nitride compound semiconductor layer having band gap energy smaller than that of said light-emitting layer.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method of controlling a greens mower, the greens mower having a motor drive system variably driving a grass cutting reel and a traction system, the method comprising:
sensing an operating parameter;
comparing the operating parameter to a predetermine parameter and outputting a control signal to the motor drive system in response thereto; and
outputting a user signal to a display member representative of the control signal to alert an operator of the operating parameter.
2. The method according to claim 1, further comprising setting the predetermined parameter by an administrator such that the predetermined parameter is unchangeable by the operator.
3. The method according to claim 12 wherein the setting the predetermined parameter by an administrator includes setting the predetermined parameter via a wireless controller.
4. The method according to claim 2 wherein the setting the predetermined parameter by an administrator includes setting the predetermined parameter via a controller releasable cable connection.
5. The method according to claim 1 wherein the sensing an operating parameter includes sensing an operating parameter chosen from the group consisting essentially of groundspeed data, motor speed data, current draw data, grass cutting reel speed data, and overall system voltage data.
6. The method according to claim 1 wherein the comparing the operating parameter to the predetermine parameter and outputting the control signal to the motor drive system in response thereto includes outputting a control signal to vary a grass cutting reel speed.
7. The method according to claim 1 wherein the comparing the operating parameter to the predetermine parameter and outputting the control signal to the motor drive system in response thereto includes outputting a control signal to vary a groundspeed.
8. A method of controlling a fleet of greens mowers, the greens mowers each having a motor drive system variably driving a grass cutting reel and a traction system, the method comprising:
setting a predetermined parameter by an administrator for each of the fleet of greens mowers such that the predetermined parameter is unchangeable by the operator;
each of the fleet of greens mowers sensing an operating parameter; and
each of the fleet of greens mowers comparing the operating parameter to a predetermine parameter and outputting a control signal to the motor drive system in response thereto.
9. The method according to claim 8, further comprising each of the fleet of greens mowers outputting a user signal to a display member representative of the control signal to alert an operator of the operating parameter.
10. The method according to claim 8 wherein the setting a predetermined parameter by an administrator for each of the fleet of greens mowers such that the predetermined parameter is unchangeable by the operator includes setting the predetermined parameter via a master controller.
11. The method according to claim 10 wherein the setting the predetermined parameter via a master controller includes simultaneously setting the predetermined parameter of each of the fleet of greens mowers via the master controller.
12. The method according to claim 10 wherein the setting the predetermined parameter via a master controller includes setting the predetermined parameter via a wireless master controller.
13. The method according to claim 10 wherein the setting the predetermined parameter via a master controller includes setting the predetermined parameter via a master controller having releasable cable connection with the fleet of greens mowers.
14. The method according to claim 8 wherein the sensing an operating parameter includes sensing an operating parameter chosen from the group consisting essentially of groundspeed data, motor speed data, current draw data, grass cutting reel speed data, and overall system voltage data.
15. The method according to claim 8 wherein the comparing the operating parameter to the predetermine parameter and outputting the control signal to the motor drive system in response thereto includes outputting a control signal to vary a grass cutting reel speed.
16. The method according to claim 8 wherein the comparing the operating parameter to the predetermine parameter and outputting the control signal to the motor drive system in response thereto includes outputting a control signal to vary a groundspeed.
17. A method of controlling a greens mower, the greens mower having a motor drive system variably driving a grass cutting reel and a traction system, the method comprising:
sensing a grass cutting reel speed;
sensing a ground speed;
calculating an actual clip rate and comparing the actual clip rate to a predetermined clip rate; and
outputting a control signal to the motor drive system to vary a speed of the grass cutting reel in response to the actual clip rate to achieve the predetermined clip rate.
18. The method according to claim 17, further comprising displaying information on a data display representative of the actual clip rate.
19. The method according to claim 17, further comprising:
sensing a current of the motor drive system; and
outputting a control signal to the motor drive system to disengage at least one of the grass cutting reel and the traction system when the current is outside a predetermined range.
20. The method according to claim 17, further comprising:
sensing a voltage of a system of the greens mower; and
outputting a control signal to the motor drive system.