Fault detection devices and fault detection methods

1. A fault detection device, adapted to an electronic device having a display screen, comprising:

a first warning unit, generating a first warning signal;

a second warning unit, generating a second warning signal;

a first sensor, disposed in front of the display screen for obtaining and outputting a first current brightness value of the display screen every first predetermined period of time; and

a microprocessor, coupled to the first warning unit, the second warning unit and the first sensor for comparing the first current brightness value with a first previous brightness value;

wherein the microprocessor enables the first warning unit to generate the first warning signal when the first current brightness value is equal to the first previous brightness value, and the microprocessor enables the second warning unit to generate the second warning signal when the first current brightness value is equal to the first previous brightness value for more than a second predetermined period of time, wherein the second predetermined period of time is greater than the first predetermined period of time;

wherein the first sensor is a light sensor; and

wherein the first warning unit is an LED and the second warning unit is a buzzer.

2. The fault detection device as claimed in claim 1 , wherein when the microprocessor determines that the first current brightness value is not equal to the first previous brightness value after enabling the first warning unit, the microprocessor disables the first warning unit.

3. The fault detection device as claimed in claim 1 , further comprising:

a second sensor, obtaining a second current brightness value of the display screen every first predetermined period of time; and

a third sensor, obtaining a third current brightness value of the display screen every first predetermined period of time;

wherein the microprocessor enables the first warning unit to generate the first warning signal when the microprocessor determines that the first current brightness value, the second current brightness value and the third current brightness value are respectively equal to the first previous brightness value, a second previous brightness value and a third previous brightness value, and the microprocessor enables the second warning unit to generate the second warning signal when the first current brightness value, the second current brightness value and the third current brightness value are respectively equal to the first previous brightness value, the second previous brightness value, and the third previous brightness value for more than the second predetermined period of time; and

wherein the second sensor is the light sensor.

4. The fault detection device as claimed in claim 3 , wherein the first sensor, the second sensor and the third sensor will not be arranged horizontally or vertically at the same time.

5. The fault detection device as claimed in claim 1 , further comprising:

a housing, having an ear-hanging structure, accommodating the first warning unit, the second warning unit, the first sensor and the microprocessor, and being mounted on the electronic device by the ear-hanging structure;

wherein the first sensor is disposed on a first surface of the housing facing the display screen, and the first warning unit and the second warning unit are disposed on a second surface with respect to the first surface.

6. A fault detection method, adapted to an electronic device having a display screen, comprising:

obtaining, using a first sensor, a first current brightness value of the display screens every first predetermined period of time, wherein the first sensor is disposed in front of the display screen;

receiving, using a microprocessor, the first current brightness value from the first sensor; and

comparing, using the microprocessor, the first current brightness value with a first previous brightness value;

when the first current brightness value is equal to the first previous brightness value, the microprocessor enables a first warning unit to generate a first warning signal by the microprocessor; and

when the first current brightness value is equal to the first previous brightness value for more than a second predetermined period of time, enabling a second warning unit to generate a second warning signal by the microprocessor;

wherein the second predetermined period of time is greater than the first predetermined period of time;

wherein the first sensor is a light sensor; and

wherein the first warning unit is an LED and the second warning unit is a buzzer.

7. The fault detection method as claimed in claim 6 , wherein when the microprocessor determines that the first current brightness value is not equal to the first previous brightness value after enabling the first warning unit, the microprocessor enables the first warning unit.

8. The fault detection method as described in claim 6 , further comprising:

obtaining, using a second sensor, a second current brightness value of the display screen every first predetermined period of time;

obtaining, using a third sensor, a third current brightness value of the display screen every first predetermined period of time;

when the microprocessor determines that the first current brightness value, the second current brightness value and the third current brightness value are respectively equal to the first previous brightness value, a second previous brightness value and a third previous brightness value, the microprocessor enables the first warning unit to generate the first warning signal; and

when the microprocessor determines that the first current brightness value, the second current brightness value and the third current brightness value are respectively and continuously equal to the first previous brightness value, the second previous brightness value and the third previous brightness value for more than a second predetermined period of time, the microprocessor enables the second warning unit to generate the second warning signal; and

wherein the second sensor is the light sensor.

9. The fault detection method as claimed claim 8 , wherein the first sensor, the second sensor and the third sensor are not arranged horizontally or vertically at the same time.

10. A fault detection method as claimed in claim 6 , wherein the first warning unit, the second warning unit, the first sensor and the microprocessor are accommodated in a housing, wherein the housing has an ear-hanging structure, and is mounted on the electronic device by the ear-hanging structure, the first sensor is disposed on a first surface of the housing facing the display screen, and the first warning unit and the second warning unit are disposed on a second surface with respect to the first surface.