rsoft_cad.geometry package

This package calculates the geometry of a taper

Submodules

rsoft_cad.geometry.custom_taper module

rsoft_cad.geometry.custom_taper.sigmoid(x, center, width, amplitude=1)

rsoft_cad.geometry.custom_taper.sigmoid_taper_ratio(z, taper_length, center1_ratio=0.33, center2_ratio=0.5, center3_ratio=0.67, width1_ratio=0.16666666666666666, width2_ratio=0.1, width3_ratio=0.16666666666666666, weight1=0.1, weight2=0.8, weight3=0.1, min_value=0, max_value=1)

Creates a realistic taper ratio using a weighted combination of three sigmoid functions.

Parameters:

zarray-like

Position values along the taper

taper_lengthfloat

Total length of the taper

center1_ratio, center2_ratio, center3_ratiofloat

Relative positions of sigmoid centers (as fraction of taper_length)

width1_ratio, width2_ratio, width3_ratiofloat

Relative widths of sigmoids (as fraction of taper_length)

weight1, weight2, weight3float

Weights for combining the sigmoid functions (should sum to 1)

min_value, max_valuefloat

Range for clipping the output values

Returns:

array-like

Taper ratio values

rsoft_cad.geometry.custom_taper.model_photonic_lantern_taper(z_points=100, taper_length=21.5, cladding_diameter=125, final_cladding_diameter=None, final_capillary_id=150, capillary_id=275, capillary_od=900, layers_config=[(3, 1.0)], core_map=None, core_diameters=None)

Models a photonic lantern taper with support for LP mode mapping and core diameters.

This function extends model_photonic_lantern_taper by adding support for mapping LP modes to fiber positions through the core_map parameter and tracking core diameters along the taper. It renames parameters for clarity and calculates final_cladding_diameter from final_capillary_id if not provided.

Parameters:

z_pointsint, optional

Number of points along the z-axis. Default is 100.

taper_lengthfloat, optional

Length of the taper in mm. Default is 21.5.

cladding_diameterfloat, optional

Initial diameter of the fiber cladding in μm. Default is 125.

final_cladding_diameterfloat, optional

Final diameter of the fiber claddings in μm. If None, calculated from final_capillary_id.

final_capillary_idfloat, optional

Final inner diameter of the capillary in μm. Default is 150.

capillary_idfloat, optional

Initial inner diameter of the capillary in μm. Default is 275.

capillary_odfloat, optional

Outer diameter of the capillary in μm. Default is 900.

layers_configlist of tuples, optional

Configuration for fiber layers if core_map is not provided. Default is [(3, 1.0)].

core_mapdict, optional

Mapping of LP mode names to initial fiber positions. If provided, overrides layers_config. Example: {“LP01”: (0, 0), “LP11a”: (100, 0), “LP11b”: (0, 100)}

core_diametersdict, optional

Dictionary mapping LP mode names to their initial core diameters in μm. Example: {“LP01”: 10.7, “LP11a”: 9.6, “LP11b”: 9.6} If not provided, all cores default to 80% of the cladding diameter.

Returns:

dict

A dictionary containing the taper model data with the following keys: - “z”: z-positions along the taper - “fiber_diameters”: Array of fiber (cladding) diameters at each z-position - “core_diameters”: Array of core diameters at each z-position - “fiber_positions”: Array of fiber positions at each z-position - “capillary_inner_diameter”: Inner diameter of the capillary at each z-position - “capillary_outer_diameter”: Outer diameter of the capillary at each z-position - “lp_modes”: List of LP mode names - “mode_positions”: Dictionary mapping LP mode names to their positions along z - “mode_core_diameters”: Dictionary mapping LP mode names to their core diameters along z

rsoft_cad.geometry.custom_taper.extract_lantern_endpoints(model_output)

Extract endpoint information for the photonic lantern taper model, including cladding, core, and capillary dimensions.

Parameters:

model_outputdict

The dictionary returned by model_photonic_lantern_taper function

Returns:

tuple

A tuple of three dictionaries (cladding_endpoints, core_endpoints, cap_endpoints): - cladding_endpoints and core_endpoints contain LP mode information - cap_endpoints contains capillary information with just width and height

Format: {

“LP01”: {

“end.x”: x_position, “end.y”: y_position, “end.z”: z_position, “end.height”: diameter, “end.width”: diameter

}

cap_endpoints format: {

“end.z”: z_position, “end.height”: inner_diameter, “end.width”: inner_diameter

}

rsoft_cad.geometry.custom_taper.plot_taper_cross_sections(model, ax_row, num_sections=6)

rsoft_cad.geometry.custom_taper.plot_taper_profile(model, ax)

rsoft_cad.geometry.custom_taper.plot_combined_taper(model, num_cross_sections=6, figsize=(15, 6))

Generates a figure with cross-sections and the longitudinal profile of the taper.

Parameters:

• model (dict) – The dictionary returned by the model_photonic_lantern_taper function.

• num_cross_sections (int, optional) – The number of cross-sections to plot. Defaults to 6.

• figsize (tuple, optional) – The size of the figure (width, height) in inches. Defaults to (15, 6).

rsoft_cad.geometry.custom_taper.create_custom_taper_profile(data_dir, expt_dir, taper_func=None, file_name='custom_profile_dim.txt', num_points=300, taper_length=1, z_range=(0, 1), header='/rn,a,b /nx0 100 0 1 1 OUTPUT_REAL\n ', save_to_rsoft_data=True, rsoft_data_dir=None, **taper_func_kwargs)

Create a custom taper profile using sigmoid function and save to file(s).

Parameters:

data_dirstr

Base directory for data

expt_dirstr

Experiment directory name

taper_funccallable, optional

Function to generate the taper profile. Should accept a numpy array of z values as first argument and return a numpy array of taper ratios. If None (default), will use sigmoid_taper_ratio.

file_namestr, optional

Name of the output file, default is “custom_profile_dim.txt”

num_pointsint, optional

Number of points in the profile, default is 300

taper_lengthfloat, optional

Length parameter for the sigmoid taper ratio, default is 1

z_rangetuple, optional

Range of z values (start, end), default is (0, 1)

headerstr, optional

Header text for the output file

save_to_rsoft_databool, optional

Whether to also save to rsoft_data_files subdirectory, default is True

rsoft_data_dir:

Data directory name.

**taper_func_kwargs :

Additional keyword arguments to pass to the taper function

Returns:

tuple

(z, taper_ratios) arrays

rsoft_cad.geometry.tapers module

rsoft_cad.geometry.tapers.calculate_taper_properties(position, start_dia=None, end_dia=None, taper_length=None, taper_factor=None)

Calculate properties at any point along a tapered section.

Parameters: position (float): Position along the taper where properties are needed start_dia (float, optional): Starting diameter end_dia (float, optional): Ending diameter taper_length (float, optional): Length of the tapered section. Defaults to 100.0 if not provided. taper_factor (float, optional): Ratio of start diameter to end diameter. Can be used instead of providing both diameters.

Returns: tuple: (diameter, taper_rate, taper_factor, end_dia)

• diameter (float): Diameter at the specified position

• taper_rate (float): Rate of change of diameter per unit length

• taper_factor (float): Ratio of start diameter to end diameter

• end_dia (float): Ending diameter