Grating and three-dimensional holographic display device

A grating, comprising:

• a first substrate and a second substrate disposed opposite to the first substrate;
• and
• a plurality of grating electrodes and a plurality of spacing pillars disposed between the first substrate and the second substrate,
• wherein:
• the plurality of grating electrodes extend along a first direction, and are arranged along a second direction;
• the first direction intersects the second direction;
• along a plane parallel to the first substrate, positions of the plurality of spacing pillars are referred to as matrix points;
• the plurality of matrix points include multiple first matrix points;
• the plurality of first matrix points are dividend into a plurality of repeating units;
• each repeating unit includes at least three first matrix points of the plurality of first matrix points;
• a repeating unit corresponding to a shape having a minimum perimeter and area is a first matrix point group;
• and
• an extension direction of a connection line of any two first matrix points in the first matrix point group is different from the first direction.

A three-dimensional holographic display device, comprising:

• a light source device, configured to emit coherent RGB three-color light in a time sequence;
• a beam expanding collimating component, configured to perform a beam expanding and collimating processing on the light emitted by the light source device;
• a spatial light modulator, configured to sequentially perform a phase modulation and an amplitude modulation on the light emitted by the beam expanding collimator component;
• a field lens, configured at least to improve an ability of an edge light of the light emitted by the spatial light modulator to enter a grating;
• and
• the grating, configured to form a left-eye image and a right-eye image based on the incident light image,
• wherein the grating includes:
• a first substrate and a second substrate disposed opposite to the first substrate;
• and
• a plurality of grating electrodes and a plurality of spacing pillars disposed between the first substrate and the second substrate,
• wherein:
• the plurality of grating electrodes extend along a first direction and are arranged along a second direction;
• along a plane parallel to the first substrate, positions of the plurality of spacing pillars are referred to as a plurality of matrix points;
• the plurality of matrix points include multiple first matrix point units;
• along the plane parallel to the first substrate, the multiple matrix point units are arranged as an array;
• a minimum repeating unit of the array includes four first matrix point units of the multiple first matrix point units;
• the four matrix point units are located at four vertices of a first quadrilateral;
• two adjacent sides of the first quadrilateral are defined as a first unit vector and a second unit vector, respectively;
• an angle between the first unit vector and the second unit vector is α1, and 0°≤α1≤90°;
• an angle between the first unit vector and the first direction is β1, and β1≠0°, and β1≠180°;
• and
• an angle between the second unit vector and the first direction is γ1, and γ1≠0°, and γ1≠180°.