Python library for the design of femtosecond laser-written integrated photonic circuits.

femto is an open-source package for the design of integrated optical circuits. The library consists of a growing list of parts and modules, which can be composed to construct complex optical components and large circuits. The optical components can be plotted and exported to a .pgm file for the fabrication of the circuit.

Table of Contents

• Installation
• Usage
• Issues

Installation

The package can be installed using pip (use Python 3.11)

python3 -m venv .venvs/femto
source .venvs/minimal/bin/activate
pip install git+ssh://git@github.com/ricalbr/femto2.git

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Usage

Here a brief example on how to use the library.

First, import all the required modules

from femto.curves import sin
from femto.device import Device
from femto.pgmcompiler import PGMCompiler
from femto.waveguide import Waveguide

Set waveguide parameters

PARAM_WG = dict(scan=4,
                speed=7.5,
                depth=0.050,
                radius=25)

Create a list of waveguides as

wgs = []

# SWG
wg = Waveguide(**PARAM_WG)
wg.start([-2, 4.5, 0.050])
wg.linear([27, 4.5, 0.050], mode='ABS')
wg.end()
wgs.append(wg)

# MZI
for i in range(6):
    wg = Waveguide(**PARAM_WG)
    wg.start([-2, 5+i*0.080, 0.500])
    wg.linear([10, 0, 0], mode='INC')
    wg.mzi(dy=(-1)**i * 0.037, dz=0, fx=sin)
    wg.linear([27, 5+i*0.080, 0.500], mode='ABS')
    wg.end()
    wgs.append(wg)

Now that the waveguides are defined, we set the fabrication parameters

PARAM_GC = dict(filename='MZIs.pgm',
                laser='PHAROS',
                samplesize=(25, 10),
                rotation_angle=0.0)

Create a Device object that allows to store the waveguides and plot them

# CIRCUIT
circuit = Device(**PARAM_GC)

# Add waveguides to circuit
circuit.extend(wgs)

# Make a plot of the circuit
circuit.plot2d()

Export the G-Code with the following commands

# Export G-Code file
with PGMCompiler(**PARAM_GC) as G:
    G.tic()
    with G.repeat(6):
        for i, wg in enumerate(wgs):
            G.comment(f' +--- Mode: {i + 1} ---+')
            G.write(wg.points)
    G.toc()
    G.go_origin()

Other example files can be found here.

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Documentation

The complete documentation can be found here.

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Issues

To request features or report bugs open an issue here

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You can finally rest, femto-writer...