quaeritis/phidl

Python GDS layout and CAD geometry creation for photonic and superconducting circuits

PHIDL

PHotonic and Integrated Device Layout - GDS CAD layout and geometry creation for photonic and superconducting circuits

• Installation / requirements
• About PHIDL
• Changelog
• Tutorial + examples

Installation / requirements

• Install or upgrade with pip install -U phidl
• Python 2 >=2.6 or Python 3 >=3.5
• If you are on Windows and don't already have gdspy installed, you will need a C++ compiler
  • For Python 3, install the MS C++ Build Tools for VS 2017
  • For Python 2, install Microsoft Visual C++ Compiler for Python 2.7

About PHIDL

fiddle (verb) - /ˈfidl/ - to make minor manual movements, especially to adjust something

PHIDL is an open-source GDS-based CAD tool for Python 2 and 3 which extends and simplifies the excellent gdspy. It strives to simplify GDSII geometry creation by making the design process layout-driven, rather than coordinate-driven. The base installation includes a large library of simple shapes (e.g. rectangles, circles), photonic structures (e.g. sine curve waveguides), and superconducting nanowire shapes (e.g. single photon detectors) which are fully parameterized. It also has a built-in quick-plotting function based on Qt (or matplotlib) which allows you view the state of any GDS object, useful when scripting geometry-making functions. It also has a very thorough tutorial as well which will walk you through the process of getting acquainted with PHIDL.

The purpose of PHIDL is to fill a void in the GDS design space: creation of elements in a simple, layout-driven, parameterized way, without a large amount of code overhead. Many GDS tools exist, but they tend to fall in one of two categories: (1) GUI-based layout tools with ad-hoc scripting interfaces, or (2) full-featured Cadence-style layout software which requires 30 lines of boilerplate/overhead code just to draw a simple ring.

The goal is to bring the usability of Illustrator / Inkscape drawing programs to the GDS scripting world. Like Python itself, it aims to be readable, and intuitive. For instance, when building a geometry you don't have to worry about what the exact coordinates are anymore. If you want to separate two ellipses in the x direction by 5 units, you can do things like this:

ellipse1.xmin = ellipse2.xmax + 5

or if you want to move then rotate one ellipse by 45 degrees you can do

ellipse2.move([1,7]).rotate(45)

There's a few dozen shortcuts like this that make life easier built into PHIDL--they're simple, but they make a world of difference when you just want to e.g. space a ring resonator some distance from a waveguide without having to track each and every coordinate of the shape.

There's also a "port" functionality which allows you to snap together geometry like Legos without caring about where exactly the absolute coordinates of either geometry is. For instance, connecting the above misaligned rectangles is a two-line command:

It also allows you to do things like add text and create smooth or straight routing curves between "ports" of different devices, convenient for making electrical or optical connections:

Other useful functionality available are standard operations like booleans:

and less standard ones like creating outlines. A whole layout can be outlined directly in the GDS without requiring you to use Beamer (useful for positive-tone resist structures):

pg.outline(D, distance = 0.7, layer = 4)

The geometry library also has useful resolution test-structures built into it, for instance

pg.litho_calipers(num_notches = 7, offset_per_notch = 0.1)
pg.litho_steps(line_widths = [1,2,4,8,16])
pg.litho_star(num_lines = 16, line_width = 3)

You can also do things like create a backing fill to make sure the resist develops uniformly while still creating a solid ground plane, with user-defined margins. Below is an image of a device which needed a ground plane. A single-line fill function was able to fill the required area (purple), electrically connecting all of the ground structures together:

Changelog

1.0.2 (March 26, 2019)

New features

• Added tutorial section for phidl.geometry library lithographic shapes (resolution tests, calipers, stars, etc)
• Added symmetric argument to pg.optimal_step()
• Experimental port phidl.geometry function pg.port_to_geometry() which converts Ports in a Device into polygon-geometry so they can be saved into the GDS file (in the style of SiEPIC). (contribution thanks to Alex Tait @atait)
• Added support for magnification and rotation of Labels (contribution thanks to Alex Tait @atait)

Changes

• Precision for boolean functions set to 1e-6 by default now
• position argument removed from pg.text()

Bugfixes

• Fixed rare but persistent bug affecting boolean operations (e.g. pg.offset(), pg.outline(), pg.boolean(), pg.union()) on polygons with sub-precision floating point errors. Will no longer cause jagged edges when two points are misaligned by very small amounts (e.g. when points that should be equal differ by 1e-27 due to floating point imprecision)
• Fix for pg.import_gds() so that items can be moved/rotated correctly after importing
• Fix for remove_layers() correctly preserves references now (contribution thanks to Alex Tait @atait)
• Suppressed unecessary warnings

1.0.1 (Jan 21, 2019)

New features

• D.remove() can now remove Ports as well as references/polygons

Bugfixes

• Can't have a major release without at least one bug! Fixed errors introduced by optimized-rotation algorithm.

1.0.0 (Jan 14, 2019)

• 1.0 release! The core functionality of phidl has been stable for over 18 months, and all major planned features have been implemented. Time to reflect that in the version number!

New features

• Significant upgrades to quickplot2: now shows coordinates, a help message box (press ?), and a scale notation (along with several under-the-hood optimizations)
• Added D.hash_geometry() -- use to generate a SHA1-based hash of the polygons in a Device
• Added phidl.utilities.load_lyp(), which loads a KLayout layer properties (.lyp) file and converts it into a LayerSet (contribution thanks to Alex Tait @atait)

Changes

• Optimized rotation so 90-degree rotations (contribution thanks to Alex Tait @atait)
• Function documentation for geometry module (contribution thanks to Jimmy Gammell @jgammell and Dylan Oh @dmwo)
• pytest implementation for internal consistency checking

0.9.0 (Oct 9, 2018)

New features

• Added pg.union() - a handy convenience function to join (union) polygons together, either by-layer or all together (see tutorial for full details)
• Added phidl.utilities.write_svg() - allows you to write your geometry directly to SVG for the sake of publishing figures easily (see tutorial for full details)
• Added pg.xor_diff(A,B) - Produces an XOR operation between Devices A and B, which can by used to compare differences between A and B (see tutorial for full details)
• Allow usage of a Python set (e.g. {3,5,6}) as an input to the layer argument of add_polygon (and thus all geometry-creation functions in phidl.geometry) to create the polygons on multiple layers. (see tutorial for full details)

Bugfixes

• None

0.8.10 (August 23, 2018)

Bugfixes

• Minor upkeep bugfixes

0.8.9 (July 24, 2018)

New features

• The addition of the argument max_cellname_length added to D.write_gds(). It is 28 by default, to guarantee maximum compatibility with GDS specifications (32 is generally the lower limit, and write_gds() applies a # afterwards to prevent duplicate cellnames).
• New documentation backend (contribution thanks to Alex Tait @atait)
• Added D.remap_layers() which allows you to to move all polygons contained on a layer within your Device to another layer. See tutorial for details
• Added D.remove_layers() which lets you remove all polygon geometry (optionally including labels) from a Device on the specified layers. See tutorial for details

Bugfixes

• Further fixes to D.write_gds() for rare edge cases

0.8.8 (July 19, 2018)

New features

• You can now add any shape to multiple layers at once by passing a whole LayerSet to the layer argument. See tutorial for details
• Update to D.write_gds() which guarantees cell names within a Device will never overlap. If you want to disable this feature for more control over cell names, change the auto_rename argument to False ( D.write('myfile.gds', auto_rename = False))

Bugfixes

• Modifications made to work with gdspy>=1.3.1

0.8.7 (July 11, 2018)

Bugfixes

• Minor bugfixes to pg.litho_calipers() and pg.litho_star()

0.8.6 (July 9, 2018)

New features

• D.absorb(my_reference) can be used to easily absorb references into a Device; polygons will be extracted from the reference, added to the Device, and then the reference will be removed. See the tutorial for more details
• Added lithographic-resolution test structures including stars (pg.litho_star()), calipers (pg.litho_calipers()), and variable-size negative-tone and positive-tone steps (pg.litho_steps()) (Contribution from Dylan Oh @dmwo).

Changes

• Made write_gds() autofix names to guarantee no duplicates cell names ever appear

Bugfixes

• The gdspy bounding box caching has been reallowed
• Single-layer flatten fix for D.flatten()
• quickplot and quickplot2 now fail gracefully if the user does not have matlplotlib or Qt respectively.

0.8.5 (June 15, 2018)

New features

• Added pg.optimal_90deg(), the optimal 90-degree turn for superconducting nanowires from Clem & Berggren

Bugfixes

• quickplot2 visual improvement: Ports now show up on top of subports
• quickplot2 visual improvement: Port colors now colorblind-friendly
• Fixed very rare make_device() error

0.8.4 (June 6, 2018)

New features

• Added << operator to add references. r = D.add_ref(Rect) can now be (optionally) written as r = D << Rect.
• Added D.get_ports() which allows you to gather the locations and information about all ports in Device.
• A LayerSet can now be previewed. Running the geometry function pg.preview_layerset() will generate a Device which shows all of the layers, useful for previewing color schemes.
• quickplot() now shows zero-width ports (e.g. a "pin") as a + sign.
• quickplot() now defaults to redrawing within a single window, rather than creating a new window for every call
• Added a .info dictionary to Port, useful for recording information about a port (e.g. myport.info['wavelength'] = 1550)
• Updated tutorial

Changes

• pg.optimal_hairpin(), pg.snspd(), and pg.snspd_expanded() now have the argument turn_ratio which defines how wide the turn is w.r.t. the argument wire_width
• The layer argument in D.add_polygon() can now accept lists of Layers. Use this if you want to a single polygon shape to multiple layers.
• Rearranged an argument location: The name argument for the Layer() class is now the third argument to allow the ability to make Layers like Layer(1,0)
• Removed some deprecated old geometry

Bugfixes

• Minor bugfix to guarantee quickplot() shows up from the Python/IPython console.
• Minor bugfix in tutorial example file

0.8.2 (Apr 19, 2018)

New features

• Added the LayerSet class. See the tutorial, but essentially this class makes a convenient container to stores layers
• Added phidl.utilities.write_lyp() (Contribution from Dylan Oh @dmwo). Using a LayerSet, you can now create KLayout-compatible .lyp files. This allows you to get the same coloring in the KLayout viewer as you have specified in PHIDL.
• Several new electrical test structures (Contribution from Jacob Melonis @melonisj) Specifically: via chain tests (pg.test_via()), inter- and intra-layer comb insulation tests (pg.test_comb()), and critical current test structures (pg.test_ic).
• add_ref() can now take a list of input Devices and will return a list of the generated references, e.g. ref_a,ref_b,ref_c = D.add_ref([A,B,C])

Changes

Bugfixes

• Fixed issue with pg.import_gds() when layers (remapping argument) was None.
• Bugfix in pg.copy() which produced incorrectly-copied ports

0.8.1 (Feb 7, 2018)

New features

• New function pg.extract() which extracts all the polygons from a set of specified layers from a Device, and creates a new Device with those polygons in them. See tutorial for details
• New Device-copying functions pg.copy() and pg.deepcopy() which allows you to copy a Device wholesale (very useful if you want to flatten() a Device but not destroy the original). pg.copy maintains the underlying connections & references to other Devices, while pg.deepcopy creates completely new copies of every underlying polygon and reference. See tutorial for details
• Introduced an LRU cache for computationally-intensive Device-making functions. By using the @device_lru_cache decorator, any function which returns a Device can be memoized. See tutorial for more details

Changes

• Since the extract() process creates new geometry, D.extract() has been removed in favor of placing it in the geometry library pg.extract()
• pg.import_gds default argument is now flatten = False
• Updated tutorial text

Bugfixes

• Fixed port deepcopy bug, should result in large performance enhancement for Devices with lots of sub-references and ports
• Fixed some rare errors with D.flatten()
• Some internal changes to make working with Device.uid easier

0.8.0 (Dec 6, 2017)

New features

• pg.import_gds() can now import without flattening all the polygons to a single layer
• Added Device.flatten() function to flatten references into raw polygons. See tutorial for details
• Added Device.remove() function to remove geometry. See tutorial for details
• Added more informative error messages
• __repr__ and __str__ implemented for Device & DeviceReference: You can now quickly get useful information about a Device by just typing the variable into the console. For instance entering D or print(D) into the Python console will print Device (name "Myshape003191", ports ['R_center', 'bottom', 'input'], aliases ['hello'], 13 elements, 13 references)

Changes

• Using a config dictionary as a specification is no longer done with Device(device_function, config = myconfig). Now it is done with an explicit function, make_device(device_function, config = myconfig) (importable as import phidl.make_device). See the tutorial for more info
• Device.meta is now being replaced with Device.info for clarity of nomenclature. Device.meta will still work but will issue a warning.
• Device.annotate() is now being replaced with Device.label() to be more consistent with GDS naming conventions. Device.annotate() will still work but will issue a warning.

Bugfixes

• Made compatible with gdspy >= 1.2
• Specified names for phidl.geometry objects

0.7.1 (August 28, 2017)

New features

• Updated tutorial text

Changes

• Large changes to pg.import_gds(). If your GDS file only has one toplevel cell, you do not need to specify a cellname, pg.import_gds() will automatically grab that cell. Also, it imports all layers by default now, although you can still choose which layers and even create a layer mapping based on whether you pass the layers argument a list or dict. See tutorial for more information.

Bugfixes

• Many small ones under the hood

0.7.0 (May 26, 2017)

New features

• Updated tutorial text significantly
• Added import_gds() function! You can now import existing GDS files and use them in your geometry. Try adding premade organization logos and hand-drawn test structures without having to code them from scratch. See tutorial for full explanation.
• Added overlap keyword argument to the connect() function. Now when connecting two ports together, you can force them to overlap. See tutorial for full explanation.
• Added point_path() function to phidl.routing. It takes a width value and list of points and and will create path of constant width which follows the list of points.

Changes

• Text scaling has been changed to be more sensible; now pg.text('abc', size = 100) will produce letters 100 units tall (previously would produce text 125 units tall).

Bugfixes

• Many small ones under the hood

0.6.5 (Apr 3, 2017)

New features

• Added pg.boolean() to perform AND/NOT/OR/XOR operations on shapes
• Added pg.outline() to create outlines of shapes, useful for positive-tone resist processes

Changes

• Switched development to Python 3. Python 2 will still be supported going forward however
• The function to expand/contract polygons pg.inset() has been deprecated in favor of the more aptly-named pg.offset(). pg.offset(D, distance = -1) will contract the shapes in D, pg.offset(D, distance = 1) will expand them.

Bugfixes

• Fixes necessary to make compatible with Python 3
• Fixed pg.connector() midpoint argument
• Compatibility fixes to make compatible with gdspy>=1.1.2

0.6.4 (Feb 21, 2017)

New features

• Added "quickplot2", a more robust/easier to use viewer which instead of being based on matplotlib is based Qt.
  • Zoom/scroll uses same buttons as KLayout
  • Toggle labels for ports/aliases with F1, F2, F3
  • Reset view with Escape key

0.6.3 (Jan 23, 2017)

Bugfixes

• Under the hood

0.6.2 (Jan 13, 2017)

New features

• Added label_aliases=False default option to quickplot. Do quickplot(D, label_aliases = True) to draw text with aliases on it
• Added Device.extract(). See the tutorial for details
• Device.add_polygon() can now receive lists of polygons, and will return lists in kind

Changes

• pg.snspd() and pg.snspd_expanded() can now be defined using any 2 constrains of: xsize, ysize, or num_squares.
• Nomenclature change on pg.fill_rectangle(), from exclude_layers to avoid_layers
• Changed pg.ytron_round() variable names, fixed layer error on cross

Bugfixes

• Fixed SNSPD squares calculation and added num_squares constraints

0.6.1 (Jan 9, 2017)

New features

• Added ability to make "alias" for DeviceReference. See the tutorial
• Can now use Port.x and Port.y instead of calling Port.midpoint[0] and Port.midpoint[1]
• Added Device.size property. Returns the equivalent of [Device.xsize, Device.ysize]
• Added include_layers to pg.fill_rectangle, allowing you to override exclude_layers
• Added pg.circle(), pg.cross(), and pg.ellipse()

Changes

• None

Bugfixes

• Fixed route_manhattan, had issue with using Device.add() instead of Device.add_ref()
• Fixed pg.snspd layer = 0 by default
• Fixed Port.endpoints

0.6.0 (Dec 13, 2016)

Changes

• phidl.geometry.route() works still but is being deprecated, will now be in phid.routing.route_basic(). pg.route() will be deleted in the near future

New features

• Several new photonic geometries by Sonia Buckley
• Advanced Manhattan routing written by Jeff Chiles

Bugfixes

• Very likely we added more bugs than we fixed in this version!

0.5.6 (Dec 12, 2016)

Bugfixes

• Fixes to phidl.geometry.hecken_taper()

Changes

• pg.taper() now has a default argument of width2=None

New features

• Fill tool (phidl.geometry.fill_rectangle) now allows you to invert the fill
• New function pg.invert() which will perform a boolean inversion on elements

0.5.5

Bugfixes

• Problem with route() and inset() caused by implementation of Layer(). You can now pass route() and inset() a Layer and it will parse it correctly

0.5.4 (Dec 5, 2016)

Changes

• A few under-the-hood optimizations

Bugfixes

• Fixed error with quickplot where the last edge of a polygon was not rendered
• Problem with route() and inset() caused by implementation of Layer(). You can now pass route() and inset() a Layer and it will parse it correctly

0.5.3 (Nov 22, 2016)

New features

• Layers() are now implemented. See tutorial_example.py "Using Layers" section for a demonstration
• You can now construct a Device using a set of parameters. See "Constructing a Device from set of parameters" in tutorial_example.py
• Usage of the annotate() function has been added to tutorial_example.py
• quickplot rendering speed has been sped up by a factor of 10x

Changes

• pg.rectangle() now takes "size" as a parameter rather than "point1" and "point2"

0.4.1 (Nov 3, 2016)

• Large number of upgrades

0.3.0 (Sep 12, 2016)

• Initial release!