Light-emitting device and production method for same

A light-emitting device that outputs light to form an optical image in at least any one direction of a normal direction of a main surface and an inclination direction inclined with respect to the normal direction, the light-emitting device comprising:

• a substrate having the main surface;
• a light-emitting portion provided on the substrate;
• and
• a phase modulation layer provided on the substrate in a state of being optically coupled to the light-emitting portion, the phase modulation layer including a base layer and a plurality of modified refractive index regions having a refractive index different from a refractive index of the base layer,
• wherein the plurality of modified refractive index regions are arranged at predetermined positions in the base layer in accordance with an arrangement pattern for formation of the optical image on a design plane of the phase modulation layer orthogonal to the normal direction,
• each of the plurality of modified refractive index regions has a three-dimensional shape defined by a first surface facing the main surface, a second surface positioned on a side opposite to the main surface with respect to the first surface, and a side surface connecting the first surface and the second surface, and
• at least one of the first surface, the second surface, and the side surface in the three-dimensional shape has a portion inclined with respect to the main surface, wherein
• each of the plurality of modified refractive index regions is arranged so as to have one-to-one correspondence with any lattice point of a virtual square lattice on the design plane of the phase modulation layer, and
• a line segment connecting any specific lattice point among a plurality of valid lattice points, associated with the plurality of modified refractive index regions among lattice points constituting the virtual square lattice, and a gravity center of a specific modified refractive index region associated with the specific lattice point is parallel to each of line segments respectively connecting remaining valid lattice points excluding the specific lattice point and remaining modified refractive index regions associated with the remaining valid lattice points.

A production method for a light-emitting device that outputs light to form an optical image in at least any one direction of a normal direction of a main surface and an inclination direction inclined with respect to the normal direction,

• the light-emitting device comprising:
• a substrate having the main surface;
• a light-emitting portion provided on the substrate;
• and
• a phase modulation layer provided on the substrate in a state of being optically coupled to the light-emitting portion, the phase modulation layer including a base layer and a plurality of modified refractive index regions having a refractive index different from a refractive index of the base layer,
• wherein the plurality of modified refractive index regions are arranged at predetermined positions in the base layer in accordance with an arrangement pattern for formation of the optical image on a design plane of the phase modulation layer orthogonal to the normal direction,
• each of the plurality of modified refractive index regions has a three-dimensional shape defined by a first surface facing the main surface, a second surface positioned on a side opposite to the main surface with respect to the first surface, and a side surface connecting the first surface and the second surface, and
• at least one of the first surface, the second surface, and the side surface in the three-dimensional shape has a portion inclined with respect to the main surface,
• the production method comprising:
• a first step of providing the base layer on the substrate;
• a second step of forming a plurality of holes or depressions that are to serve as the plurality of modified refractive index regions in the base layer by dry etching;
• and
• a third step of forming a cap layer on the base layer, the cap layer covering opening portions of the plurality of holes or depressions formed in the base layer,
• wherein a material gas for formation of the cap layer is applied to the base layer from a direction inclined with respect to the normal direction in the third step.