rectangular_spiral

photonforge.parametric.rectangular_spiral(*, port_spec=None, turns=None, radius=None, separation=None, size=None, full_length=None, align_ports=None, active_model=None, technology=None, name=None, bend_kwargs=None, straight_kwargs=None, tidy3d_model_kwargs=None, circuit_model_kwargs=None)[source]

Rectangular spiral.

Parameters:

  • port_spec (Annotated[str | PortSpec, _Metadata(type=PortSpec, title=None, description=None, units=None, required=False, minimum=None, maximum=None, exclusive_minimum=None, exclusive_maximum=None, min_items=None, max_items=None)] | None) – Port specification describing waveguide cross-section.

  • turns (Annotated[int, _Metadata(type=None, title=None, description=None, units=None, required=False, minimum=2, maximum=None, exclusive_minimum=None, exclusive_maximum=None, min_items=None, max_items=None)] | None) – Number of turns in each of the 2 spiral arms.

  • radius (Annotated[float, _Metadata(type=None, title=None, description=None, units=μm, required=False, minimum=None, maximum=None, exclusive_minimum=0, exclusive_maximum=None, min_items=None, max_items=None)] | None) – Bend radius for the spiral turns.

  • separation (Annotated[float, _Metadata(type=None, title=None, description=None, units=μm, required=False, minimum=0, maximum=None, exclusive_minimum=None, exclusive_maximum=None, min_items=None, max_items=None)] | None) – Distance between waveguide centers in parallel sections. If None, defaults to the port width.

  • size (Annotated[Sequence[Annotated[float, _Metadata(type=None, title=None, description=None, units=μm, required=False, minimum=0, maximum=None, exclusive_minimum=None, exclusive_maximum=None, min_items=None, max_items=None)]], _Metadata(type=None, title=None, description=None, units=None, required=False, minimum=None, maximum=None, exclusive_minimum=None, exclusive_maximum=None, min_items=2, max_items=2)] | None) – Spiral dimensions measured from the waveguide centers. If None, defaults to (0, 0).

  • full_length (Annotated[float, _Metadata(type=None, title=None, description=None, units=μm, required=False, minimum=None, maximum=None, exclusive_minimum=0, exclusive_maximum=None, min_items=None, max_items=None)]) – Desired spiral length. If set to a positive value, ‘turns’ and ‘size[1]’ are calculated automatically.

  • align_ports (Annotated[Literal['', 'x', 'y'], ~photonforge.parametric._Metadata(type=None, title=None, description=None, units=None, required=False, minimum=None, maximum=None, exclusive_minimum=None, exclusive_maximum=None, min_items=None, max_items=None)] | None) – Optionally align ports to have centers with same "x" or "y" coordinates.

  • active_model (Annotated[Literal['Tidy3D', 'Waveguide'], ~photonforge.parametric._Metadata(type=None, title=None, description=None, units=None, required=False, minimum=None, maximum=None, exclusive_minimum=None, exclusive_maximum=None, min_items=None, max_items=None)] | None) – Name of the model to be used by default; must be either "Tidy3D" or "Circuit" (default).

  • technology (Annotated[Technology, _Metadata(type=None, title=None, description=None, units=None, required=False, minimum=None, maximum=None, exclusive_minimum=None, exclusive_maximum=None, min_items=None, max_items=None)] | None) – Component technology. If None, the default technology is used.

  • name (Annotated[str, _Metadata(type=None, title=None, description=None, units=None, required=False, minimum=None, maximum=None, exclusive_minimum=None, exclusive_maximum=None, min_items=None, max_items=None)] | None) – Component name.

  • bend_kwargs (Annotated[dict[str, Any], _Metadata(type=required, title=False, description=None, units=None, required=False, minimum=None, maximum=None, exclusive_minimum=None, exclusive_maximum=None, min_items=None, max_items=None)] | None) – Dictionary of keyword arguments for bend().

  • straight_kwargs (Annotated[dict[str, Any], _Metadata(type=required, title=False, description=None, units=None, required=False, minimum=None, maximum=None, exclusive_minimum=None, exclusive_maximum=None, min_items=None, max_items=None)] | None) – Dictionary of keyword arguments for straight().

  • tidy3d_model_kwargs (Annotated[dict[str, Any], _Metadata(type=required, title=False, description=None, units=None, required=False, minimum=None, maximum=None, exclusive_minimum=None, exclusive_maximum=None, min_items=None, max_items=None)] | None) – Dictionary of keyword arguments passed to the component’s photonforge.Tidy3DModel.

  • circuit_model_kwargs (Annotated[dict[str, Any], _Metadata(type=required, title=False, description=None, units=None, required=False, minimum=None, maximum=None, exclusive_minimum=None, exclusive_maximum=None, min_items=None, max_items=None)] | None) – Dictionary of keyword arguments passed to the component’s photonforge.CircuitModel.

Returns:

Component with path sections, ports and model.

Return type:

Component

Note

The full length of the spiral can be computed with the photonforge.route_length() function.

# Compact spiral
component1 = rectangular_spiral(
    port_spec="Strip", radius=5, turns=7, bend_kwargs={"euler_fraction": 0.5}
)

# Horizontally aligned ports
component2 = rectangular_spiral(
    port_spec="Strip", radius=5, turns=7, align_ports="y", bend_kwargs={"euler_fraction": 0.5}
)

# Vertically aligned ports, predefined length, bulging straight sections
component3 = rectangular_spiral(
    port_spec="Strip",
    radius=5,
    full_length=500,
    size=(75, 0),
    align_ports="x",
    bend_kwargs={"euler_fraction": 0.5},
    straight_kwargs={"bulge_width": 0.7, "bulge_taper_length": 10, "bulge_margin": 2},
)
rectangular_spiral