"""Spiral with grating couplers inside to save space."""
from __future__ import annotations
import numpy as np
import gdsfactory as gf
from gdsfactory.component import Component
from gdsfactory.components.add_grating_couplers import (
add_grating_couplers_with_loopback_fiber_array,
)
from gdsfactory.components.bend_euler import bend_euler, bend_euler180
from gdsfactory.components.straight import straight as straight_function
from gdsfactory.routing.manhattan import round_corners
from gdsfactory.snap import snap_to_grid, snap_to_grid2x
from gdsfactory.typings import ComponentFactory, ComponentSpec, CrossSectionSpec
def get_bend_port_distances(bend: Component) -> tuple[float, float]:
p0, p1 = bend.ports.values()
return abs(p0.x - p1.x), abs(p0.y - p1.y)
[docs]
@gf.cell
def spiral_inner_io(
N: int = 6,
x_straight_inner_right: float = 150.0,
x_straight_inner_left: float = 50.0,
y_straight_inner_top: float = 50.0,
y_straight_inner_bottom: float = 10.0,
grating_spacing: float = 127.0,
waveguide_spacing: float = 3.0,
bend90: ComponentSpec = bend_euler,
bend180: ComponentSpec = bend_euler180,
straight: ComponentSpec = straight_function,
length: float | None = None,
cross_section: CrossSectionSpec = "xs_sc",
cross_section_bend: CrossSectionSpec | None = None,
cross_section_bend180: CrossSectionSpec | None = None,
asymmetric_cross_section: bool = False,
**kwargs,
) -> Component:
"""Returns Spiral with ports inside the spiral loop.
You can add grating couplers inside the spiral to save space.
Args:
N: number of loops.
x_straight_inner_right: xlength.
x_straight_inner_left: x length left.
y_straight_inner_top: x inner top.
y_straight_inner_bottom: y length.
grating_spacing: defaults to 127 for fiber array.
waveguide_spacing: center to center spacing.
bend90: bend90 spec.
bend180: bend180 spec.
straight: straight spec.
length: spiral target length (um), overrides x_straight_inner_left.
to match the length by a simple 1D interpolation.
cross_section: spec.
cross_section_bend: for the bends.
cross_section_bend180: for 180 bend.
asymmetric_cross_section: if the cross_section is asymmetric, it needs to be mirrored at the halfway point.
kwargs: cross_section settings.
"""
dx = dy = waveguide_spacing
cross_section_bend = cross_section_bend or cross_section
cross_section_bend180 = cross_section_bend180 or cross_section_bend
xs_bend180 = gf.get_cross_section(cross_section_bend180, **kwargs)
xs_bend = gf.get_cross_section(cross_section_bend, **kwargs)
xs = gf.get_cross_section(cross_section, **kwargs)
x_straight_inner_right = snap_to_grid2x(x_straight_inner_right)
x_straight_inner_left = snap_to_grid2x(x_straight_inner_left)
y_straight_inner_top = snap_to_grid2x(y_straight_inner_top)
y_straight_inner_bottom = snap_to_grid2x(y_straight_inner_bottom)
if length:
x_straight_inner_left = get_straight_length(
length=length,
spiral_function=spiral_inner_io,
N=N,
x_straight_inner_right=x_straight_inner_right,
x_straight_inner_left=x_straight_inner_left,
y_straight_inner_top=y_straight_inner_top,
y_straight_inner_bottom=y_straight_inner_bottom,
grating_spacing=grating_spacing,
waveguide_spacing=waveguide_spacing,
)
_bend180 = gf.get_component(bend180, cross_section=xs_bend180)
_bend90 = gf.get_component(bend90, cross_section=xs_bend)
rx, ry = get_bend_port_distances(_bend90)
_, rx180 = get_bend_port_distances(_bend180) # rx180, second arg since we rotate
component = Component()
p1 = gf.Port(
name="o1",
center=(0, y_straight_inner_top),
orientation=270,
cross_section=xs_bend,
)
p2 = gf.Port(
name="o2",
center=(grating_spacing, y_straight_inner_top),
orientation=270,
cross_section=xs_bend,
)
component.add_port(name="o1", port=p1)
component.add_port(name="o2", port=p2)
# Create manhattan path going from west grating to westmost port of bend 180
_pt = np.array(p1.center)
pts_w = [_pt]
for i in range(N):
y1 = y_straight_inner_top + ry + (2 * i + 1) * dy
x2 = grating_spacing + 2 * rx + x_straight_inner_right + (2 * i + 1) * dx
y3 = -y_straight_inner_bottom - ry - (2 * i + 3) * dy
x4 = -x_straight_inner_left - (2 * i + 1) * dx
if i == N - 1:
x4 = x4 - rx180 + dx
_pt1 = np.array([_pt[0], y1])
_pt2 = np.array([x2, _pt1[1]])
_pt3 = np.array([_pt2[0], y3])
_pt4 = np.array([x4, _pt3[1]])
_pt5 = np.array([_pt4[0], 0])
_pt = _pt5
pts_w += [_pt1, _pt2, _pt3, _pt4, _pt5]
route_west = round_corners(
pts_w, bend=_bend90, straight=straight, cross_section=cross_section, **kwargs
)
component.add(route_west.references)
# Add loop back
bend180_ref = _bend180.ref(port_id="o2", position=route_west.ports[1], rotation=90)
component.add(bend180_ref)
# Create manhattan path going from east grating to eastmost port of bend 180
_pt = np.array(p2.center)
pts_e = [_pt]
for i in range(N):
y1 = y_straight_inner_top + ry + (2 * i) * dy
x2 = grating_spacing + 2 * rx + x_straight_inner_right + 2 * i * dx
y3 = -y_straight_inner_bottom - ry - (2 * i + 2) * dy
x4 = -x_straight_inner_left - (2 * i) * dx
_pt1 = np.array([_pt[0], y1])
_pt2 = np.array([x2, _pt1[1]])
_pt3 = np.array([_pt2[0], y3])
_pt4 = np.array([x4, _pt3[1]])
_pt5 = np.array([_pt4[0], 0])
_pt = _pt5
pts_e += [_pt1, _pt2, _pt3, _pt4, _pt5]
if asymmetric_cross_section:
cross_section = xs_bend
cross_section_bend = xs
_bend90 = gf.get_component(bend90, cross_section=cross_section_bend, **kwargs)
route_east = round_corners(
pts_e, bend=_bend90, straight=straight, cross_section=cross_section, **kwargs
)
component.add(route_east.references)
length = route_east.length + route_west.length + _bend180.info["length"]
component.info["length"] = snap_to_grid(length + 2 * y_straight_inner_top)
return component
[docs]
@gf.cell
def spiral_inner_io_fiber_array(
N: int = 6,
x_straight_inner_right: float = 150.0,
x_straight_inner_left: float = 50.0,
y_straight_inner_top: float = 50.0,
y_straight_inner_bottom: float = 10.0,
grating_spacing: float = 127.0,
waveguide_spacing: float = 3.0,
bend90: ComponentSpec = bend_euler,
bend180: ComponentSpec = bend_euler180,
straight: ComponentSpec = straight_function,
length: float | None = 20e3,
cross_section: CrossSectionSpec = "xs_sc",
cross_section_bend: CrossSectionSpec | None = None,
cross_section_bend180: CrossSectionSpec | None = None,
cross_section_loopback: CrossSectionSpec = "xs_sc",
asymmetric_cross_section: bool = False,
add_grating_couplers: ComponentFactory
| None = add_grating_couplers_with_loopback_fiber_array,
**kwargs,
) -> Component:
"""Returns Spiral with fiber array grating couplers.
Args:
N: number of loops.
x_straight_inner_right: xlength.
x_straight_inner_left: x length left.
y_straight_inner_top: x inner top.
y_straight_inner_bottom: y length.
grating_spacing: defaults to 127 for fiber array.
waveguide_spacing: center to center spacing.
bend90: bend90 spec.
bend180: bend180 spec.
straight: straight spec.
length: spiral target length (um), overrides x_straight_inner_left.
to match the length by a simple 1D interpolation.
cross_section: spec.
cross_section_bend: for the bends.
cross_section_bend180: for 180 bend.
asymmetric_cross_section: if the cross_section is asymmetric, it needs to be mirrored at the halfway point.
add_grating_couplers: function to add grating couplers.
kwargs: cross_section settings.
"""
spiral = spiral_inner_io(
N=N,
x_straight_inner_right=x_straight_inner_right,
x_straight_inner_left=x_straight_inner_left,
y_straight_inner_top=y_straight_inner_top,
y_straight_inner_bottom=y_straight_inner_bottom,
grating_spacing=grating_spacing,
waveguide_spacing=waveguide_spacing,
bend90=bend90,
bend180=bend180,
straight=straight,
length=length,
cross_section=cross_section,
cross_section_bend=cross_section_bend,
cross_section_bend180=cross_section_bend180,
asymmetric_cross_section=asymmetric_cross_section,
**kwargs,
)
return (
add_grating_couplers(spiral, cross_section=cross_section_loopback)
if add_grating_couplers
else spiral
)
[docs]
@gf.cell
def spiral_inner_io_fiber_single(
cross_section: CrossSectionSpec = "xs_sc",
cross_section_bend: CrossSectionSpec | None = None,
cross_section_ports: CrossSectionSpec | None = None,
x_straight_inner_right: float = 40.0,
x_straight_inner_left: float = 75.0,
y_straight_inner_top: float = 10.0,
y_straight_inner_bottom: float = 0.0,
grating_spacing: float = 200.0,
**kwargs,
) -> Component:
"""Returns Spiral with 90 and 270 degree ports.
You can add single fiber north and south grating couplers
inside the spiral to save space
Args:
cross_section: for the straight sections in the spiral.
cross_section_bend: for the bends in the spiral.
cross_section_ports: for input/output ports.
x_straight_inner_right: in um.
x_straight_inner_left: in um.
y_straight_inner_top: in um.
y_straight_inner_bottom: in um.
grating_spacing: in um.
Keyword Args:
N: number of loops.
waveguide_spacing: center to center spacing.
bend90: bend90 spec.
bend180: bend180 spec.
straight: straight spec.
length: computes spiral length from simple interpolation.
kwargs: cross_section settings.
"""
c = Component()
spiral = spiral_inner_io(
cross_section=cross_section,
cross_section_bend=cross_section_bend,
x_straight_inner_right=x_straight_inner_right,
x_straight_inner_left=x_straight_inner_left,
y_straight_inner_top=y_straight_inner_top,
y_straight_inner_bottom=y_straight_inner_bottom,
grating_spacing=grating_spacing,
**kwargs,
)
ref = c << spiral
ref.rotate(90)
cross_section_ports = cross_section_ports or cross_section_bend or cross_section
bend = bend_euler(cross_section=cross_section_ports)
btop = c << bend
bbot = c << bend
c.copy_child_info(spiral)
bbot.connect("o2", ref.ports["o1"])
btop.connect("o1", ref.ports["o2"])
c.add_port("o2", port=btop.ports["o2"])
c.add_port("o1", port=bbot.ports["o1"])
return c
def get_straight_length(
length: float, spiral_function: ComponentSpec, **kwargs
) -> float:
"""Returns y_spiral to achieve a particular spiral length.
Args:
length: target length.
spiral_function: spiral function.
kwargs: spiral function kwargs.
"""
x0 = 50
x1 = 400
kwargs["x_straight_inner_left"] = x0
spiral0 = spiral_function(**kwargs)
kwargs["x_straight_inner_left"] = x1
spiral1 = spiral_function(**kwargs)
p = np.polyfit(
np.array([x0, x1]),
np.array([spiral0.info["length"], spiral1.info["length"]]),
deg=1,
)
# print(x_straight_inner_left)
lenght_dx = (length - p[1]) / p[0]
return gf.snap.snap_to_grid2x(lenght_dx)
if __name__ == "__main__":
import gdsfactory as gf
cross_section = gf.cross_section.xs_rc2
xs1 = gf.cross_section.pn()
xs2 = xs1.mirror()
c = gf.components.spiral_inner_io_fiber_array(
cross_section=xs1,
cross_section_bend=xs2,
# cross_section_bend180=partial(cross_section, mirror=True),
waveguide_spacing=20,
# radius=30,
asymmetric_cross_section=True,
length=40e3,
)
c.show()
