Structured light projector and electronic device including the same
Provided is a structured light projector including a light source configured to emit light, and a nanostructure array configured to form a dot pattern based on the light emitted by the light source, the nanostructure array including a plurality of super cells each respectively including a plurality of nanostructures, wherein each of the plurality of super cells includes a first sub cell that includes a plurality of first nanostructures having a first shape distribution and a second sub cell that includes a plurality of second nanostructures having a second shape distribution.
1. A structured light projector comprising:
a light source configured to emit light; and
a nanostructure array configured to form a dot pattern based on the light emitted by the light source, the nanostructure array comprising a plurality of super cells, and each of the plurality of super cells comprising a plurality of nanostructures,
wherein each of the plurality of super cells comprises a first sub cell that comprises a plurality of first nanostructures having a first shape distribution and a second sub cell that comprises a plurality of second nanostructures having a second shape distribution, and
wherein the first sub cell and the second sub cell are sub-divided areas of each of the plurality of super cells that are different from each other.
2. The structured light projector of claim 1 , wherein the light source comprises a plurality of light-emitting elements.
3. The structured light projector of claim 2 , wherein the plurality of light-emitting elements and the plurality of super cells are provided in two-dimensional periodic lattices, respectively.
4. The structured light projector of claim 3 , wherein a ratio of a lattice constant of the plurality of light-emitting elements to a lattice constant of the plurality of super cells is a rational number.
5. The structured light projector of claim 3 , wherein the two-dimensional periodic lattices of the plurality of light-emitting elements and the two-dimensional periodic lattices of the plurality of super cells have a same shape and different sizes.
6. The structured light projector of claim 3 , wherein the two-dimensional periodic lattices of the plurality of light-emitting elements and the two-dimensional periodic lattices of the plurality of super cells have a same shape and a same size.
7. The structured light projector of claim 6 , wherein a distance between the light source and the nanostructure array is an integer multiple of C 2 /2λ, in which C is a lattice constant of a super cell and λ is a central wavelength of the light emitted by the light source.
8. The structured light projector of claim 1 , wherein the first shape distribution and the second shape distribution are different from each other.
9. The structured light projector of claim 8 , wherein the first sub cell and the second sub cell have equal areas.
10. The structured light projector of claim 1 , wherein each super cell of the plurality of super cells further comprises kth sub cells respectively comprising a plurality of kth nanostructures having a kth shape distribution, in which k is an integer from 3 to N and N is an integer greater than 3.
11. The structured light projector of claim 10 , wherein the first through Nth sub cells included in each super cell of the plurality of super cells are provided in a two dimensional periodic lattice.
12. The structured light projector of claim 11 , wherein each of the first through Nth sub cells included in each super cell of the plurality of super cells has an area corresponding to an equally divided area of each super cell of the plurality of super cells.
13. The structured light projector of claim 10 , wherein first through Nth shape distributions of the plurality of first nanostructures through a plurality of Nth nanostructures included in each of the first through Nth sub cells are different from each other.
14. The structured light projector of claim 10 , wherein phase profiles of the first through Nth sub cells are associated with each other based on a predetermined rule, and
wherein each of the first through Nth sub cells is configured to modulate a phase of incident light based on the phase profiles of the first through Nth sub cells, respectively.
15. The structured light projector of claim 14 , wherein a phase profile for an mth sub cell comprises a local phase profile that is common to the first through Nth sub cells and a global phase profile corresponding to a position of each super cell of the plurality of super cells in which the mth sub cell is included, in which m is an integer from 1 to N and N is an integer greater than or equal to 3.
16. The structured light projector of claim 1 , wherein the plurality of first nanostructures and the plurality of second nanostructures, respectively, have shape dimensions that are less than a wavelength of the light emitted by the light source.
17. The structured light projector of claim 16 , wherein a pitch of the plurality of first nanostructures and a pitch of the plurality of second nanostructures are less than or equal to ½ of the wavelength of the light emitted by the light source.
18. The structured light projector of claim 16 , wherein a height of each first nanostructure and a height of each second nanostructure are less than or equal to ⅔ of the wavelength of the light emitted by the light source.
19. The structured light projector of claim 1 , wherein each of the plurality of first nanostructures and each of the plurality of second nanostructures comprises a material having a refractive index that is different from a refractive index of a surrounding material by 0.5 or more.
20. The structured light projector of claim 1 , wherein the dot pattern comprises a random pattern, and
wherein the random pattern comprises a plurality of dots forming a cluster that is regularly arranged.
21. An electronic device comprising:
a structured light projector comprising:
a light source configured to emit light; and
a nanostructure array configured to form a dot pattern based on the light emitted by the light source, the nanostructure array comprising a plurality of super cells, and each of the plurality of super cells comprising a plurality of nanostructures,
wherein each of the plurality of super cells comprises a first sub cell that comprises a plurality of first nanostructures having a first shape distribution and a second sub cell that comprises a plurality of second nanostructures having a second shape distribution, and
wherein the first sub cell and the second sub cell are sub-divided areas of each of the plurality of super cells that are different from each other;
a first sensor configured to receive light reflected by an object that is irradiated by the light emitted by the structured light projector; and
a processor configured to obtain first information regarding a depth position of the object based on the light received by the first sensor.
22. The electronic device of claim 21 , further comprising:
a second sensor configured to receive the light reflected by the object,
wherein the processor is further configured to obtain second information regarding the depth position of the object based on the light received by the second sensor.
23. The electronic device of claim 22 , wherein the processor is further configured to obtain depth information of the object based on at least one of the first information and the second information.
24. A structured light projector comprising:
a light source configured to emit light, the light source comprising a plurality of light-emitting elements; and
a nanostructure array configured to form a dot pattern based on the light emitted by the light source and comprising a plurality of super cells, each of the plurality of super cells comprising a plurality of sub cells,
wherein each of the plurality of super cells comprises a first sub cell that comprises a plurality of first nanostructures having a first shape distribution and a second sub cell that comprises a plurality of second nanostructures having a second shape distribution,
wherein each of the plurality of sub cells is configured to modulate a phase of light emitted by the light source based on a phase profile of each of the plurality of sub cells, and
wherein the plurality of sub cells are sub-divided areas of each of the plurality of super cells that are different from each other.
25. The structured light projector of claim 24 , wherein the phase profile of each of the plurality of sub cells are set based on a predetermined rule corresponding to the dot pattern.
26. The structured light projector of claim 24 , wherein the plurality of light-emitting elements and the plurality of super cells are provided in two-dimensional periodic lattices, respectively, and
wherein the two-dimensional periodic lattices of the plurality of light-emitting elements and the two-dimensional periodic lattices of the plurality of super cells have a same shape.