Beam steering method and device
A beam steering method and device are provided. The beam steering method includes outputting, from a hologram recording medium on which a plurality of signal light beams having different steering information are recorded, signal light beam having specific steering information, by making reference light having a specific characteristic incident on the hologram recording medium. The method further includes o obtaining information about an object existing in the external environment based on the output signal light.
1. A beam steering method comprising:
making first reference light, having a first characteristic, incident on a hologram recording medium on which signal light is holographically recorded, wherein the signal light comprises first signal light having first steering information and recorded using the first reference light and second signal light having second steering information, different from the first steering information and recorded using a second reference light, wherein the making the first reference light incident on the hologram recording medium causes outputting the first signal light to an external environment; and
obtaining information about an object existing in the external environment using the output first signal light,
wherein the hologram recording medium is configured to output at least one of:
a first signal light group comprising a plurality of first signal light beams having divergence angles greater than a reference angle, and
a second signal light group comprising a plurality of second signal light beams having divergence angles less than the reference angle.
2. The beam steering method of claim 1 , further comprising:
making the second reference light, having a second characteristic different from the first characteristic, incident on the hologram recording medium, thereby outputting the second signal light
wherein the information about the object is obtained using the output first signal light and the output second signal light.
3. The beam steering method of claim 2 , wherein the first characteristic and the second characteristic each comprise at least one of a wavelength and a phase of light.
4. The beam steering method of claim 1 , wherein the first steering information and the second steering information each comprise at least one of an output direction and a divergence angle.
5. The beam steering method of claim 1 , wherein the information about the object comprises at least one of an absence or a presence of the object, a position of the object, and distance information about the object.
6. The beam steering method of claim 1 , wherein the outputting the first signal light group comprises scanning the external environment by outputting the plurality of first signal light beams included in the first signal light group in different output directions.
7. The beam steering method of claim 1 , wherein the outputting the first signal light group comprises sequentially outputting, one by one, the plurality of first signal light beams included in the first signal light group.
8. The beam steering method of claim 1 , wherein the obtaining of the information about the object comprises determining a target region in the external environment within which the object exists using the output first signal light group.
9. The beam steering method of claim 8 , wherein the outputting the second signal light group comprises scanning the target region by outputting the plurality of second signal light beams included in the second signal light group in different output directions.
10. The beam steering method of claim 9 , further comprising obtaining distance information about the object using the output second signal light group.
11. A beam steering device comprising:
a light source configured to output reference light comprising first reference light having a first characteristic and second reference light having a second characteristic, different from the first characteristic; and
a hologram recording medium on which signal light is holographically recorded, wherein the signal light comprises first signal light having first steering information and recoded using the first reference light and second signal light having second steering information and recorded using the second reference light;
a processor configured to obtain information about an object existing in an external environment based on the signal light;
wherein the hologram recording medium is configured to scan the external environment by outputting at least the first signal light having the first steering information when the first reference light is made incident on the hologram recording medium,
wherein the hologram recording medium is configured to output at least one of:
a first signal light group comprising a plurality of first signal light beams having divergence angles greater than a reference angle, and
a second signal light group comprising a plurality of second signal light beams having divergence angles less than the reference angle.
12. The beam steering device of claim 11 , wherein the hologram recording medium is further configured to output the second signal light having the second steering information when the second reference light is made incident on the hologram recording medium.
13. The beam steering device of claim 11 , wherein the first characteristic and the second characteristic each comprise at least one of a wavelength and a phase of light.
14. The beam steering device of claim 11 , wherein the first steering information and the second steering information each comprise at least one of an output direction and a divergence angle.
15. The beam steering device of claim 11 , wherein the information about the object comprises at least one of an absence or a presence of the object, a position of the object, and distance information about the object.
16. The beam steering device of claim 11 , wherein the hologram recording medium is configured to output the plurality of first signal light beams in different output directions.
17. The beam steering device of claim 11 , wherein the processor is configured to determine a target region in the external environment in which the object exists using the first signal light group and to obtain distance information about the object based on the second signal light group.
18. A beam steering method comprising:
providing a hologram recording medium on which signal light is recorded, wherein the signal light comprises at least a broad signal light beam having a divergence angle greater than a reference angle and at least a first narrow signal light beam and a second narrow signal light beam each having a divergence angle less than the reference angle;
making first reference light, having a first characteristic, incident on the hologram recording medium, thereby causing the hologram recording medium to output the broad signal light beam;
obtaining primary information about an object using the broad signal light beam;
making second reference light, having a second characteristic different from the first characteristic, incident on the hologram recording medium, thereby causing the hologram recording medium to output at least one of the first narrow signal light beam and the second narrow signal light beam; and
obtaining secondary information about the object using the at least one of the first narrow signal light beam and the second narrow signal light beam.