Grating, grating driving method and 3D display device

A 3D display device, comprising:

• a display screen and a grating disposed at a light-exiting side of the display screen;
• wherein the grating comprises:
• a first substrate;
• wherein the first substrate comprises a first electrode layer and a second electrode layer stacked on the first electrode layer, each of the first electrode layer and the second electrode layer comprises a plurality of strip-shaped electrodes with an identical width, and the strip-shaped electrodes in the first electrode layer and the strip-shaped electrodes in the second electrode layer are arranged alternately;
• a second substrate oppositely arranged with respect to the first substrate;
• a liquid crystal layer between the first substrate and the second substrate;
• a plurality of driving modules configured to drive the plurality of the strip-shaped electrodes to enable liquid crystals to be deflected to form light shading parts and light transmission parts;
• wherein a grating unit is defined by one light shading part and one adjacent light transmission part, a grating part is defined by at least one grating unit, the plurality of driving modules are arranged in one-to-one correspondence with the grating parts;
• and
• a control module configured to generate a plurality of driving signals in one-to-one correspondence with the plurality of the driving modules according to a distance between the human eyes and the grating, thereby changing a width of the grating unit corresponding to a crosstalk position, and enabling each light transmission part in the grating part corresponding to the crosstalk position to move close to or away from a center of the grating,
• wherein the control module comprises:
• a first control unit configured to obtain a corresponding relationship between a grating driving parameter and a distance between human eyes and a grating;
• wherein the grating driving parameter comprises a grating unit corresponding to the crosstalk position and a width of the grating unit corresponding to the crosstalk position;
• a second control unit configured to determine a current distance between the human eyes and the grating;
• a third control unit configured to, when the current distance between the human eyes and the grating is outside an optimal viewing distance, according to the corresponding relationship and the current distance between the human eyes and the grating, obtain a grating driving parameter corresponding to the current distance;
• and
• a fourth control unit configured to, according to the grating driving parameter corresponding to the current distance, generate a corresponding driving signal for changing a width of the grating unit corresponding to the crosstalk position, and moving each light transmission part in the grating part corresponding to the crosstalk position close to or away from a center of the grating,
• wherein the first control unit includes a first control sub-unit configured to obtain a first distance that the human eyes are able to move in a direction perpendicular to a display screen with respect to the optimal viewing distance according to the following formulas:
• the optimal viewing distance
• AP
• =
• h
• *
• PO
• QB
• -
• PO
• ;
• when moving to a point C close to the display screen in a direction perpendicular to the display screen, a distance between the human eyes and the grating is
• CP
• =
• h
• *
• PR
• QB
• -
• PO
• ;
• when moving to a point C away from the display screen in a direction perpendicular to the display screen, a distance between the human eyes and the grating 10 is
• EP
• =
• h
• *
• PS
• QB
• -
• PO
• ;
• PR=PO−RO;
• PS=PO+OS, and
• wherein “h” represents a distance between the grating and the display screen;
• a point P is an intersection point of an optimal viewing point A to a vertical line of the grating;
• a point O represents a position of a grating unit corresponding to a sub-pixel B at an edge of the display screen, which is viewed when the human eyes are at the point A;
• a point Q is an intersection point of the point A to the vertical line of the display screen;
• RO represents a width of at least one strip-shaped electrode;
• and OS represents a width of at least one strip-shaped electrode.