Optical communication device
An optical communication device includes a plurality of laser sources, a plurality of first meta-lenses, and an optical fiber. The laser sources transmit a plurality of laser beams in the same direction according to electrical signals. The laser beams have different wavelengths. The first meta-lenses receive the laser beams, and in a first substrate, refract the laser beams to a focal point to generate a mixed laser beam. The optical fiber receives the mixed laser beam for transmission. The focal point is arranged at the input end of the optical fiber.
1. An optical communication device, comprising:
a plurality of laser sources, transmitting a plurality of laser beams in the same direction according to electrical signals; wherein the laser beams have different wavelengths;
a plurality of first meta-lenses, receiving the laser beams, and in a first substrate, refracting the laser beams to a focal point to generate a mixed laser beam;
an optical fiber, receiving the mixed laser beam for transmission; wherein the focal point is arranged at the input end of the optical fiber,
wherein each of the first meta-lenses is designed individually, so that the refraction angles of the laser beams passing through the first meta-lenses will match the numerical aperture (NA) of the optical fiber.
2. The optical communication device as claimed in claim 1 , further comprising:
a plurality of second meta-lenses, arranged between the laser sources and the first meta-lenses;
wherein the second meta-lenses refract the laser beams, so that beam profiles of the laser beams change from an oval to a circle.
3. The optical communication device as claimed in claim 2 , wherein each first and second meta-lens comprises a plurality of cylinders with different diameters.
4. The optical communication device as claimed in claim 3 , wherein the distance between the first meta-lenses and the optical fiber is greater than the diameters of the first meta-lenses.
5. The optical communication device as claimed in claim 2 , wherein the laser sources and the first and second meta-lenses are formed on a second substrate; the first and second meta-lenses are formed on the top surface of a buffer layer; and the buffer layer is between the first and second meta-lenses and the second substrate.
6. The optical communication device as claimed in claim 5 , wherein the thickness of the buffer layer can be adjusted, so that the height of the laser sources is aligned with that of the first and second meta-lenses.
7. The optical communication device as claimed in claim 5 , wherein the first substrate comprises a glass, and the second substrate comprises indium phosphide (InP), gallium arsenide (GaAs), gallium nitride (GaN), or sapphire.
8. The optical communication device as claimed in claim 1 , wherein the wavelengths of the laser beams are between 1530 nanometers and 1565 nanometers.
9. The optical communication device as claimed in claim 1 , wherein the distance between the first meta-lenses and the optical fiber is equal to the thickness of the first substrate.
10. The optical communication device as claimed in claim 1 , wherein the mixed laser beam is transmitted in a single-mode in the optical fiber.
11. The optical communication device as claimed in claim 1 , further comprising:
a third meta-lens, receiving the mixed laser beam from the optical fiber, and parallelizing the mixed laser beam;
a grating, dispersing the mixed laser beam to recover the laser beams with different wavelengths;
a plurality of fourth meta-lenses, receiving the laser beams, and refracting and focusing the laser beams to a plurality of second optical fibers; wherein the second optical fibers receive the respective laser beams with different wavelengths.
12. The optical communication device as claimed in claim 11 , wherein each of the fourth meta-lenses is designed individually, so that the refraction angles of the laser beams passing through the fourth meta-lenses can match the numerical aperture (NA) of the second optical fibers.
13. The optical communication device as claimed in claim 11 , wherein the first, second and fourth meta-lenses, the third meta-lens, and the grating comprise a single crystal silicon, a polycrystalline silicon, an amorphous silicon, silicon nitride (Si 3 N 4 ), gallium phosphide (GaP), titanium dioxide (TiO 2 ), aluminum antimonide (AlSb), aluminum arsenide (AlAs), aluminum gallium arsenide (AlGaAs), aluminum gallium indium phosphide (AlGaInP), boron phosphide (BP), or zinc germanium phosphide (ZnGeP 2 ).
14. The optical communication device as claimed in claim 1 , wherein the laser sources are semiconductor lasers.