Apparatus and method for obtaining three-dimensional depth image

An apparatus for obtaining an image, the apparatus comprising:

• a light source configured to emit first light to a first region of an object for a first time period without illuminating the object other than the first region, emit second light to a second region of the object for a second time period, without illuminating the object other than the second region, and emit third light to the first region of the object for a third time period, without illuminating the object other than the first region;
• an image sensor configured to be synchronized with the light source, obtain a plurality of first partial images based on the first light reflected from the first region and a plurality of third partial images based on the third light reflected from the first region, through a region of the image sensor corresponding to the first region, and obtain a plurality of second partial images based on the second light reflected from the second region, through a region of the image sensor corresponding to the second region;
• and
• a processor configured to obtain a first partial depth image comprising depth information based on the first light reflected from the first region, obtain a second partial depth image based on the second light reflected from the second region, obtain a third partial depth image based on the third light reflected from the first region, obtain a first full depth image of the object based on the first partial depth image and the second partial depth image, at a first image processing time after the first time period and the second time period, and obtain a second full depth image of the object based on the second partial depth image and the third partial depth image, at a second image processing time after the first time period, the second time period, and the third time period,
• wherein the second partial depth image is used for both the first full depth image obtained at the first image processing time and the second full depth image obtained at the second image processing time, and frame rates of the first full depth image and the second full depth image are equal to frame rates of the first partial depth image, the second partial depth image, and the third partial depth image, and
• wherein the first time period, the second time period, and the third time period are different from each other, and
• wherein the image sensor is further configured to modulate a plurality of pieces of the first light into signals with different gain waveforms.