Source code for kqcircuits.elements.waveguide_coplanar_curved

# This code is part of KQCircuits
# Copyright (C) 2021 IQM Finland Oy
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from math import pi, sin, cos

from kqcircuits.elements.element import Element
from kqcircuits.pya_resolver import pya
from kqcircuits.util.geometry_helper import vector_length_and_direction
from kqcircuits.util.parameters import Param, pdt, add_parameters_from
from kqcircuits.elements.waveguide_coplanar_straight import WaveguideCoplanarStraight

[docs]def arc(r, start, stop, n): """ Returns list of points of an arc Args: r: radius start: begin angle in radians stop: end angle in radians n: number of corners in full circle .. MARKERS_FOR_PNG 0,91 0,100 """ n_steps = max(round(abs(stop - start) * n / (2 * pi)), 1) step = (stop - start) / n_steps r_corner = r / cos(step / 2) pts = [pya.DPoint(r * cos(start), r * sin(start))] for i in range(n_steps): alpha = start + step * (i + 0.5) pts.append(pya.DPoint(r_corner * cos(alpha), r_corner * sin(alpha))) pts.append(pya.DPoint(r * cos(stop), r * sin(stop))) return pts
[docs]@add_parameters_from(WaveguideCoplanarStraight, "add_metal") class WaveguideCoplanarCurved(Element): """The PCell declaration of a curved segment of a coplanar waveguide. Coordinate origin is left at the center of the arc. """ alpha = Param(pdt.TypeDouble, "Curve angle (rad)", pi) length = Param(pdt.TypeDouble, "Actual length", 0, unit="μm", readonly=True)
[docs] def coerce_parameters_impl(self): # Update length self.length = self.r * abs(self.alpha)
[docs] def build(self): left_inner_arc, left_outer_arc, right_inner_arc, right_outer_arc, left_protection_arc, right_protection_arc, \ annotation_arc = WaveguideCoplanarCurved.create_curve_arcs(self, self.alpha) # Left gap pts = left_inner_arc + left_outer_arc shape = pya.DPolygon(pts) self.cell.shapes(self.get_layer("base_metal_gap_wo_grid")).insert(shape) # Right gap pts = right_inner_arc + right_outer_arc shape = pya.DPolygon(pts) self.cell.shapes(self.get_layer("base_metal_gap_wo_grid")).insert(shape) # Protection layer pts = left_protection_arc + right_protection_arc self.add_protection(pya.DPolygon(pts)) # Waveguide lenght pts = annotation_arc shape = pya.DPath(pts, self.a) self.cell.shapes(self.get_layer("waveguide_path")).insert(shape) if self.add_metal: self.cell.shapes(self.get_layer("base_metal_addition")).insert(shape)
[docs] @staticmethod def create_curve_arcs(elem, angle): """Creates arcs of points for a curved waveguide. Args: elem: Element from which the waveguide parameters for the arc are taken angle (double): angle of the curved waveguide Returns: A tuple consisting of lists of points, each list representing one of the arcs. (left_gap_inner, left_gap_outer, right_gap_inner, right_gap_outer, left_protection, right_protection, annotation) """ alphastart = 0 alphastop = angle left_gap_inner = arc(elem.r - elem.a/2, alphastart, alphastop, elem.n) left_gap_outer = arc(elem.r - elem.a/2 - elem.b, alphastop, alphastart, elem.n) right_gap_inner = arc(elem.r + elem.a/2, alphastart, alphastop, elem.n) right_gap_outer = arc(elem.r + elem.a/2 + elem.b, alphastop, alphastart, elem.n) left_protection = arc(elem.r - elem.a/2 - elem.b - elem.margin, alphastart, alphastop, elem.n) right_protection = arc(elem.r + elem.a/2 + elem.b + elem.margin, alphastop, alphastart, elem.n) annotation = arc(elem.r, alphastart, alphastop, elem.n) return left_gap_inner, left_gap_outer, right_gap_inner, right_gap_outer, left_protection, right_protection,\ annotation
[docs] @staticmethod def produce_curve_termination(elem, angle, term_len, trans, face_index=0, opp_face_index=1): """Produces termination for a curved waveguide. The termination consists of a rectangular polygon in the metal gap layer, and grid avoidance around it. The termination is placed at the position where a curved waveguide with alpha=angle and trans=trans would end. Args: elem: Element from which the waveguide parameters for the termination are taken angle (double): angle of the curved waveguide term_len (double): termination length, assumed positive trans (DTrans): transformation applied to the termination face_index (int): face index of the face in elem where the termination is created opp_face_index (int): face index of the opposite face """ left_inner_arc, left_outer_arc, right_inner_arc, right_outer_arc, left_protection_arc, right_protection_arc,\ _ = WaveguideCoplanarCurved.create_curve_arcs(elem, angle) # direction of the termination box _, term_dir = vector_length_and_direction(left_outer_arc[0] - left_outer_arc[1]) if term_len > 0: # metal gap for termination pts = [ left_inner_arc[-1], left_outer_arc[0], left_outer_arc[0] + term_len*term_dir, right_outer_arc[0] + term_len*term_dir, right_outer_arc[0], right_inner_arc[-1], ] shape = pya.DPolygon(pts) elem.cell.shapes(elem.layout.layer(elem.face(face_index)["base_metal_gap_wo_grid"])).insert(trans*shape) # grid avoidance for termination protection_pts = [ left_protection_arc[-1], left_protection_arc[-1] + (term_len + elem.margin)*term_dir, right_protection_arc[0] + (term_len + elem.margin)*term_dir, right_protection_arc[0], ] elem.add_protection(trans * pya.DPolygon(protection_pts), face_index, opp_face_index)