A 3D display panel , comprising: a lower substrate , comprising a plurality of columns of subpixels in which preset columns of subpixels which are in an OFF state serve as a buffer zone; a grating , comprising a plurality of aperture areas and a plurality of shielding areas, which are configured to allow images of one part of subpixels in the lower substrate to enter a left eye of a viewer, and allow images of the other part of subpixels in the lower substrate to enter a right eye of the viewer; and a positioning unit configured to determine a first distance which the viewer moves, and determine whether any subpixel of non-buffer zone is shielded by the grating according to the first distance; characterized in that it further comprises an adjusting unit configured to adjust the buffer zone when the any subpixel of non-buffer zone is shielded by the grating , so as to avoid the decrease of brightness or the occurrence of color cast in the 3D image seen by the user, in that two buffer zones are separated by a distance of P columns of subpixels in the lower substrate , and each buffer zone comprises Q columns of subpixels, each aperture area of the grating allowing an image with a width of P columns of subpixels in the lower substrate to enter into the viewer's eyes, and each shielding area of the grating shields an image with a width of Q columns of subpixels in the lower substrate , P and Q being positive integers, and Q≤P≤2Q; and in that in response to determining that J columns of subpixels of non-buffer zone are shielded by the grating , the adjusting unit is further configured to turn on corresponding J columns of subpixels in the buffer zone at a distance of P columns subpixels from the J columns of subpixels of non-buffer zone, wherein 1<J≤Q. a lower substrate , comprising a plurality of columns of subpixels in which preset columns of subpixels which are in an OFF state serve as a buffer zone; a grating , comprising a plurality of aperture areas and a plurality of shielding areas, which are configured to allow images of one part of subpixels in the lower substrate to enter a left eye of a viewer, and allow images of the other part of subpixels in the lower substrate to enter a right eye of the viewer; and a positioning unit configured to determine a first distance which the viewer moves, and determine whether any subpixel of non-buffer zone is shielded by the grating according to the first distance; characterized in that it further comprises an adjusting unit configured to adjust the buffer zone when the any subpixel of non-buffer zone is shielded by the grating , so as to avoid the decrease of brightness or the occurrence of color cast in the 3D image seen by the user, in that two buffer zones are separated by a distance of P columns of subpixels in the lower substrate , and each buffer zone comprises Q columns of subpixels, each aperture area of the grating allowing an image with a width of P columns of subpixels in the lower substrate to enter into the viewer's eyes, and each shielding area of the grating shields an image with a width of Q columns of subpixels in the lower substrate , P and Q being positive integers, and Q≤P≤2Q; and in that in response to determining that J columns of subpixels of non-buffer zone are shielded by the grating , the adjusting unit is further configured to turn on corresponding J columns of subpixels in the buffer zone at a distance of P columns subpixels from the J columns of subpixels of non-buffer zone, wherein 1<J≤Q. <EOS>