Image sensor and imaging device including the same

1. An image sensor configured to generate illuminance data by receiving a light signal, the light signal including image information of an object and ambient light information, the image sensor comprising:

a sensing module including a pixel array, the sensing module configured to sense the light signal irradiated to the pixel array, and configured to generate pixel data corresponding to the sensed light signal; and

an illuminance data generator configured to generate the illuminance data corresponding to ambient light based on the pixel data, wherein

the illuminance data generator is configured to generate the illuminance data based on the pixel data when the light signal is not focused on the pixel array,

wherein the pixel array includes a plurality of sensing units, the plurality of sensing units including at least two of a plurality of unit pixels, and

the illuminance data generator is configured to select a plurality of valid sensing units from among the plurality of sensing units by performing a sub-sampling operation with respect to the pixel array, and the illuminance data generator is configured to generate the illuminance data based on a valid pixel data corresponding to the selected plurality of valid sensing units, and

wherein the pixel array includes a light sensing unit exposed to light brighter than a reference illuminance and a shade sensing unit exposed to light dimmer than the reference illuminance, and

the illuminance data generator is configured to generate the illuminance data based on the valid pixel data, the valid pixel data including a valid pixel data of a short-time exposure pixel in the light sensing unit with respect to the light sensing unit and a valid pixel data of a long-time exposure pixel in the shade sensing unit with respect to the shade sensing unit.

2. The image sensor of claim 1 , further comprising:

a focus detector configured to sense whether the light signal is focused on the pixel array and to output an illuminance data generation signal to the illuminance data generator when the light signal is not focused on the pixel array.

3. The image sensor of claim 1 , further comprising:

a focus adjuster configured to adjust a focus of the light signal.

4. The image sensor of claim 1 , further comprising:

an image data generator configured to generate image data corresponding to the object based on the pixel data.

5. The image sensor of claim 4 , further comprising:

a mode selector configured to selectively activate at least one of the image data generator or the illuminance data generator.

6. The image sensor of claim 1 , wherein

at least one of the plurality of valid sensing units includes at least one long-time exposure pixel and at least one short-time exposure pixel.

7. The image sensor of claim 1 , wherein

the pixel array includes at least one first sensing unit and at least one second sensing unit, and

the first sensing unit includes one long-time exposure pixel and three short-time exposure pixels, and the second sensing unit includes one short-time exposure pixel and three long-time exposure pixels.

8. The image sensor of claim 1 , wherein

the illuminance data generator does not use at least one of the valid pixel data.

9. The image sensor of claim 8 , wherein

when illuminance in illuminance information included in the valid pixel data is equal to or greater than a reference illuminance, the illuminance data generator does not use the valid pixel data when generating the illuminance data.

10. An imaging device comprising:

a lens configured to concentrate a light signal, the light signal including image information of an object and ambient light information;

a focus adjusting module configured to adjust a focus of the light signal; and

an image sensor including a sensing module, the sensing module including a pixel array, the pixel array including a plurality of sensing units, the sensing module configured to sense the light signal irradiated to the pixel array and to generate a pixel data corresponding to the sensed light signal, the image sensor further including an illuminance data generator configured to generate illuminance data corresponding to ambient light based on the pixel data, wherein

the illuminance data generator is configured to select a plurality of valid sensing units from among the plurality of sensing units by performing a sub-sampling operation with respect to the pixel array, and the illuminance data generator is configured to generate the illuminance data based on valid pixel data corresponding to the plurality of valid sensing units when the light signal is not focused on the pixel array, and

at least one of the plurality of valid sensing units includes a light sensing unit exposed to bright light and a shade sensing unit exposed to dim light,

at least one of the light sensing unit and the shade sensing unit comprises at least one long-time exposure pixel and at least one short-time exposure pixel, and

the illuminance data generator is configured to generate the illuminance data based on valid pixel data, the valid pixel data including a valid pixel data of a short-time exposure pixel in the light sensing unit with respect to the light sensing unit and a valid pixel data of a long-time exposure pixel in the shade sensing unit with respect to the shade sensing unit.

11. The imaging device of claim 10 , wherein

the focus adjusting module is configured to perform an auto-focusing operation automatically adjusting the light signal focused on the pixel array,

the image sensor further includes a focus detector configured to output an illuminance data generation signal to the illuminance data generator when the light signal is not focused on the pixel array before the auto-focusing operation is completed, and

the illuminance data generator is configured to generate the illuminance data based on valid pixel data when the light signal is not focused on the sensing module in response to the illuminance data generation signal.

12. The imaging device of claim 10 , wherein

the illuminance data generator does not use at least some of the valid pixel data to generate the illuminance data according to a reference illuminance.

13. An electronic system comprising:

an application processor; and

an image sensor connected to the application processor, the image sensor including

a pixel array, and

an image sensor processor configured to operate in a first mode to sense a light signal irradiated to the pixel array, to generate pixel data corresponding to the sensed light signal, and to generate illuminance data corresponding to ambient light based on the pixel data when the light signal is not focused on the pixel array, wherein

the pixel array includes a light sensing unit exposed to light brighter than a reference illuminance and a shade sensing unit exposed to light dimmer than the reference illuminance, and

the image sensor processor is configured to generate the illuminance data based on a valid pixel data, the valid pixel data including a valid pixel data of a short-time exposure pixel in the light sensing unit with respect to the light sensing unit and a valid pixel data of a long-time exposure pixel in the shade sensing unit with respect to the shade sensing unit.

14. The electronic system of claim 13 , further comprising:

a display connected to the application processor.

15. The electronic system of claim 13 , wherein the image sensor processor is further configured to,

sense whether the light signal is focused on the pixel array, and

operate in a second mode to generate image data corresponding to an object based on the pixel data.

16. The electronic system of claim 15 , wherein the image sensor processor is configured to operate in the first mode when the image sensor processor senses that the light signal is not focused on the pixel array.

17. The electronic system of claim 15 , wherein

the image sensor processor is configured to adjust a focus of the light signal in such a manner that a lens is not focused on the pixel array before the image sensor processor generates the illuminance data, and wherein

the image sensor processor is configured to adjust the focus of the light signal in such a manner that the lens is focused on the pixel array before the image sensor processor generates the image data.