A display apparatus for detecting three-dimensional (3D) spatial information. The display apparatus includes a display panel having a plurality of active subpixels in a display area configured with multiple gaps respectively between at least some active subpixels, the display panel including a counter substrate at front and a backplane substrate at back; an optical layer at a back side of the backplane substrate; multiple light sensors attached discretely on a back side of the optical layer and substantially aligned with the multiple gaps in the display area; and a light source on the backplane substrate and configured to provide an infrared light signal in a direction toward a field of view beyond the counter substrate. The multiple light sensors are configured to detect respective infrared light signals reflected from multiple different regions of an object in the field of view for collectively deducing 3D spatial information of the object.