Optical phased arrays (OPAs) have been widely used for many applications in the last few years. Optical phased arrays are used in many fields like holographic video displays, free-space optical communication systems and light detection and ranging (LIDAR) systems. Lidar is a remote sensing technique that emits the collimated light beam and measures the time it takes for the reflections to be detected by the signal. This is used to compute the distances to the objects.
Thermal tuning of the optical array with uniform spacing is used to induce a phase shift in waveguides. Heaters of the same length with a linear increase in power will change the refractive index of the waveguides. The change in refractive index will cause a phase shift to the waveguides. Since the waveguides in the optical phased array are placed in uniform spacing, the temperature rise (crosstalk) between the waveguides has been examined in this work. It has been noticed that the temperature rise (crosstalk) between the waveguides will increase in uniform spacing. Therefore, the temperature rise between the waveguides is reduced to 2 K for a fixed area by giving non-uniform spacing between the waveguides.
Then, the far-field analysis of the optical phased array with a single input has been evaluated. The electric field intensity and far-field pattern of the optical phased array are evaluated. The shifting of the beam along the theta direction is given in this work.

Optical phased arrays (OPAs) have been widely used for many applications in the last few years. Optical phased arrays are used in many fields like holographic video displays, free-space optical communication systems and light detection and ranging (LIDAR) systems. Lidar is a remote sensing technique that emits the collimated light beam and measures the time it takes for the reflections to be detected by the signal. This is used to compute the distances to the objects.
Thermal tuning of the optical array with uniform spacing is used to induce a phase shift in waveguides. Heaters of the same length with a linear increase in power will change the refractive index of the waveguides. The change in refractive index will cause a phase shift to the waveguides. Since the waveguides in the optical phased array are placed in uniform spacing, the temperature rise (crosstalk) between the waveguides has been examined in this work. It has been noticed that the temperature rise (crosstalk) between the waveguides will increase in uniform spacing. Therefore, the temperature rise between the waveguides is reduced to 2 K for a fixed area by giving non-uniform spacing between the waveguides.
Then, the far-field analysis of the optical phased array with a single input has been evaluated. The electric field intensity and far-field pattern of the optical phased array are evaluated. The shifting of the beam along the theta direction is given in this work.

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