Silicon-based integrated optically adjustable delay line based on optical phased array

1. A silicon-based and an optical phased array-based integrated optically adjustable delay line, comprising

an optical phased array transmitting unit ( 101 ) comprising an output end,

a slab waveguide transmitting unit ( 102 ) comprising a first end and a second end, and

an optical phased array receiving unit ( 103 );

wherein the output end of the optical phased array transmitting unit ( 101 ) is connected with the first end of the slab waveguide transmitting unit ( 102 ), and the second end of the slab waveguide transmitting unit ( 102 ) is connected with the optical phased array receiving unit ( 103 );

the optical phased array transmitting unit ( 101 ) is sequentially composed of a coupler, a cascaded beam splitting structure, and a phase shifter phase array; and

the optical phased array receiving unit ( 103 ) is sequentially composed of a phase shifter phase array, a cascaded beam splitting structure, and a coupler.

2. The integrated optically adjustable delay line according to claim 1 , wherein the optical phased array transmitting unit ( 101 ) and the optical phased array receiving unit ( 103 ) are arranged symmetrically with respect to the slab waveguide transmitting unit ( 102 ) or at the same side of the slab waveguide transmitting unit ( 102 ).

3. The integrated optically adjustable delay line according to claim 1 , wherein the optical phased array transmitting unit ( 101 ) transmits a wave beam having directivity by beam forming and is connected to the first end of the slab waveguide transmitting unit ( 102 );

an input light beam larger than a total reflection critical angle is constrained to be transmitted in the slab waveguide transmitting unit ( 102 );

the other end of the slab waveguide transmitting unit ( 102 ) is connected to the optical phased array receiving unit ( 103 ); and

according to an optical path reversibility principle, the second end of the slab waveguide transmitting unit ( 102 ) receives an optical signal transmitted from a specific angle in the slab waveguide transmitting unit ( 102 ) so as to complete a connection of the optical path from the input to the output.

4. A method for adjusting light delay using the integrated optically adjustable delay line of claim 1 , comprising

regulating a phase difference between channels by the phase shifter phase array of the optical phased array transmitting unit ( 101 ) or the optical phased array receiving unit ( 103 ) to change a far-field interference light spot and forming a wave beam with directivity,

changing an angle of a light beam of the optical phased array transmitting unit ( 101 ) or the optical phased array receiving unit ( 103 ),

changing a length of a propagation path of the light beam in the slab waveguide; and

adjusting the light delay.

5. The integrated optically adjustable delay line according to claim 1 , wherein an input coupler of the optical phased array of the optical phased array transmitting unit ( 101 ) or the optical phased array receiving unit ( 103 ) adopts a grating coupler or an inverse taper, and an external signal that is an input and output through the coupler in the optical phased array transmitting unit ( 101 ) or the optical phased array receiving unit ( 103 ) adopts horizontal coupling or vertical coupling to realize a connection between an external optical signal and a planar optical waveguide; and

the horizontal coupling adopts a lens, and an inverted cone spot-size converter on a chip, and the vertical coupling adopts a planar optical fiber, and a grating coupler on the chip.

6. The integrated optically adjustable delay line according to claim 1 , wherein the cascaded beam splitting structure of the optical phased array transmitting unit ( 101 ) is a beam splitter that employs a cascaded multimode interference coupler, a cascaded Y-beam splitter, or a star coupler.

7. The integrated optically adjustable delay line according to claim 1 , wherein the phase shifter of the optical phased array transmitting unit ( 101 ) or of the optical phased array receiving unit ( 103 ) adopts a phase shifter based on a free carrier dispersion effect or a phase shifter based on a thermo-optic effect.

8. The integrated optically adjustable delay line according to claim 1 , wherein the optical phased array has a sub-wavelength spaced antenna density to enable a large angular range of non-aliased light beam deflection, and the transmit array uses a curved waveguide array, a waveguide array of different widths, or a photonic bandgap structure containing metamaterials to enable coupling suppression between transmit units.

9. The integrated optically adjustable delay line according to claim 1 , wherein the optical phased array receiving unit comprises a mirror image structure with the optical phased array transmitting unit, and uses different array size, sub-channel number, sub-channel phase adjusting principle, beam combining device, output coupler, or a combination thereof from the optical phased array transmitting unit.

10. A method for increasing receiving efficiency or receiving integrated of the optically adjustable delay line according to claim 1 , comprising

increasing an array size of a receiver or the number of sub-channels in the optical phased array receiving unit ( 103 ).