Sleep warning apparatus

1. A sleep warning apparatus comprising:

stimulation generating means for generating stimulation to a person before a warning is given to the person, the stimulation being used to take reaction of the person;

reaction detecting means for detecting the reaction of the person to the stimulation when the stimulation generated by the stimulation generating means is given to the person;

warning determining means for determining whether or not the warning is required to be given to the person depending on whether or not the reaction detecting means detects the reaction of the person to the stimulation; and

warning generating means for giving the warning to the person when the warning determining means determines that the warning is required to be given to the person, wherein the reaction detecting means detects at least one of behavior of the person and a biosignal as the reaction of the person to the stimulation; and

when the reaction detecting means detects the reaction of the person to the stimulation, the stimulation generating means automatically without manual intervention is stopped from generating the stimulation.

2. The sleep warning apparatus according to claim 1 , wherein the stimulation generating means generates the stimulation, to which the person is able to react while the person is awake.

3. The sleep warning apparatus according to claim 1 , wherein:

the person receives the stimulation generated by the stimulation generating means through a first sense organ of the person; and

the person receives the warning generated by the warning generating means through a second sense organ of the person.

4. The sleep warning apparatus according to claim 1 , wherein:

the stimulation generating means generates the stimulation to the person through a generation source that changes a position as time elapses.

5. The sleep warning apparatus according to claim 1 , further comprising:

surrounding stimulation obtaining means for obtaining surrounding stimulation that the person receives from a surrounding environment, wherein:

the stimulation generating means increases or decreases an intensity of the stimulation to the person based on the surrounding stimulation taken by the surrounding stimulation taking means.

6. The sleep warning apparatus according to claim 5 , wherein the stimulation generating means intermittently increases or decreases the intensity of the stimulation to the person.

7. The sleep warning apparatus according to claim 5 , wherein:

the stimulation generating means gradually increases or decreases the intensity of the stimulation to the person as time elapses.

8. The sleep warning apparatus according to claim 1 , wherein:

the stimulation generating means generates a white noise as the stimulation to the person.

9. The sleep warning apparatus according to claim 1 , further comprising:

sleepiness level determining means for determining a sleepiness level of the person, which level changes with an intensity of sleepiness of the person, wherein:

the stimulation generating means generates the stimulation at a time when the sleepiness level determined by the sleepiness level determining means exceeds a predetermined warning threshold value.

10. The sleep warning apparatus according to claim 1 , wherein:

the reaction detecting means detects a certain movement of a sight line of the driver as the reaction of the person to the stimulation.

11. The sleep warning apparatus according to claim 1 , wherein:

the reaction detecting means detects the reaction of the person to the stimulation in accordance with an appearance of the person.

12. The sleep warning apparatus according to claim 1 , wherein:

the reaction detecting means detects the reaction of the person to the stimulation in accordance with an image of a predetermined facial expression of the person.

13. The sleep warning apparatus according to claim 1 , wherein:

the reaction of the person detected by the reaction detecting means is a predetermined involuntary reaction of the person to the stimulation.