Watch type terminal and method for controlling the same

1. A watch type terminal, comprising:

a main body; and

a first sensing unit disposed on one side of the main body and comprising:

at least one green light emitting device configured to output green light, wherein the at least one green light emitting device comprises four green light emitting devices;

at least one yellow light emitting device spaced apart from the at least one green light emitting device and configured to output yellow light, a skin transmittance of the yellow light being different from a skin transmittance of the green light; and

a light receiving sensor surrounded by the at least one green light emitting device and the at least one yellow light emitting device, the light receiving sensor configured to receive light reflected from at least one of the green or yellow light;

a second sensing unit configured to detect a movement of the main body; and

a controller configured to:

generate a biometric signal based on the reflected light;

cause each of the four green light emitting devices to output green light one by one in an alternating manner when the movement detected by the second sensing unit is a first level;

activate two green light emitting devices facing each other, among the four green emitting devices, simultaneously when the movement detected by the second sensing unit is a second level that is higher than the first level; and

activate all of the four green light emitting devices continuously when the movement detected by the second sensing unit is a third level that is higher than the second level.

2. The terminal of claim 1 , wherein the controller is further configured to:

cause the at least one yellow light emitting device to output the yellow light based on the generated biometric signal.

3. The terminal of claim 2 , wherein the controller is further configured to:

cause the at least one green light emitting device to output a first quantity of green light; and

cause the at least one green light emitting device to output a second quantity of green light that is greater than the first quantity of green light based on the generated biometric signal.

4. The terminal of claim 3 , further comprising a display, wherein the controller is further configured to cause the display to display a guide image for guiding a change of a position of the main body when the biometric signal generated after outputting the yellow light is within an abnormal range.

5. The terminal of claim 1 , wherein:

each of the four green light emitting devices is spaced apart from the light receiving sensor by a first length;

the first sensing unit further comprises a red light emitting device spaced apart from the light receiving sensor by a second length that is longer than the first length; and

the red light emitting device is configured to output red light.

6. The terminal of claim 5 , wherein the controller is further configured to:

switch the four green light emitting devices into an inactive state when a sleep mode is activated;

activate the red light emitting device to measure and calculate an oxygen saturation value using the red light; and

deactivate the red light emitting device when the sleep mode is inactivated and when at least part of the four green light emitting devices is activated to measure the biometric signal.

7. The terminal of claim 6 , wherein the controller is further configured to:

cause the at least one green light emitting device and the at least one yellow light emitting device to be in an inactive state while the red light is output; and

deactivate the red light emitting device while the at least one of the green or yellow light is output.

8. The terminal of claim 6 , wherein the at least one green light emitting device and the at least one yellow light emitting device are implemented as an infrared-integrated light emitting diode (IR-integrated LED).

9. The terminal of claim 6 , wherein:

the light receiving sensor comprises a first light receiving sensor and a second light receiving sensor; and

the first and second light receiving sensors are disposed between the at least one green light emitting device and the at least one yellow light emitting device or disposed to be spaced apart from the at least one green light emitting device based on the at least one yellow light emitting device when the IR sensor, the at least one green light emitting device, the at least one yellow light emitting device, and the red light emitting device are arranged sequentially.

10. The terminal of claim 6 , wherein:

the light receiving sensor comprises a first light receiving sensor and a second light receiving sensor;

the IR sensor, the at least one yellow light emitting device, the first and second light receiving sensors, and the red light emitting device are arranged in one direction; and

first and second green light emitting devices of the at least one green light emitting device are arranged in a direction intersecting with the one direction.

11. The terminal of claim 1 , further comprising:

a display disposed on a front side of the main body; and

a rear cover disposed on a back side of the main body,

wherein the rear cover comprises:

a protruding portion protruding from one surface of the rear cover, the sensing unit mounted on the protruding portion; and

a window coupled to the protruding portion to form an outer surface of the rear cover, the window allowing transmission of light.

12. The terminal of claim 11 , wherein:

each of the at least one green light emitting device and the at least one yellow light emitting device is spaced apart from the light receiving sensor by a preset first length on a circuit board;

the window overlaps the circuit board to cover the at least one green light emitting device, the at least one yellow light emitting device, and the light receiving sensor; and

the window comprises:

a transparent area corresponding to the at least one green light emitting device, the at least one yellow light emitting device, and the light receiving sensor; and

a mask area not allowing transmission of light.

13. The terminal of claim 11 , wherein:

each of the at least one green light emitting device and the at least one yellow light emitting device is spaced apart from the light receiving sensor by a preset first length on a circuit board; and

at least one opaque light shielding barrier wall is disposed between the at least one green light emitting device and the light receiving sensor and between the at least one yellow light emitting device and the light receiving sensor.

14. The terminal of claim 13 , wherein the window is shaped to form a hole in which an end portion of the at least one opaque light shielding barrier wall is inserted.

15. The terminal of claim 13 , wherein the at least one opaque light shielding barrier wall surrounds the light receiving sensor and includes an opening through which light is incident onto the light receiving sensor.

16. The terminal of claim 11 , further comprising an accommodating unit configured to accommodate the sensing unit therein,

wherein the accommodating unit comprises:

a base portion having a plurality of receiving grooves in which the at least one green light emitting device, the at least one yellow light emitting device, and the light receiving sensor are mounted; and

a mask portion protruding from the base portion to surround a receiving groove in which the light receiving sensor is received.

17. The terminal of claim 1 , wherein:

each of the at least one green light emitting device and the at least one yellow light emitting device is spaced apart from the light receiving sensor by a first length;

the sensing unit further comprises an infrared (IR) sensor; and

the IR sensor is spaced apart from the light receiving sensor by a second length that is longer than the first length.

18. The terminal of claim 17 , wherein the controller is further configured to detect whether the terminal is worn on a user via the IR sensor.