# OptiBPM Overview

OptiBPM is a computer-aided design software tool enabling design of complex optical waveguides, which perform guiding, coupling, switching, splitting, multiplexing, and demultiplexing of optical signals in photonic devices. OptiBPM is based on the Beam Propagation Method (BPM) of simulating the passage of light through any waveguide medium, both isotropic and anisotropic. With OptiBPM you can observe the near field distribution and examine the radiation and guided field, simultaneously. OptiBPM can improve a design engineer’s productivity, reduce risk, and lower overall costs related to design of waveguide devices.

## Applications

- Design optical splitters, combiners, couplers, multiplexers, and modulators.
- Large scale optical circuit design capabilities
- Mature AWG design environment
- Model non-symmetrical waveguide structures
- Channel, rib or ridge waveguide design
- Buried waveguides
- Waveguides from a diffused process
- Sensor structures

## KEY FEATURES AND FUNCTIONALITY

### Integrated Environment

OptiBPM can combine channel, fiber, and diffused waveguides into a single layout. A simple menu selection allows a layout to be simulated in either 2D or 3D. Integration with OptiSystem delivers continuity in simulation from the waveguide to the system or subsystem level. Complex field data transfer between OptiFDTD and popular ray tracing tools, allows OptiBPM designers to incorporate free space optical elements.

### Waveguide Shapes

A vast number of waveguide shapes are available, including: Linear, Arc, Tapered (Linear, Parabolic, and Exponential), and S-Bend (Arc, Sine, and Cosine). Waveguides are fully parameterized so waveguide position and all other waveguide properties can be controlled with simple expressions. User defined waveguides allow arbitrary shapes to be created and used in a layout. These custom

waveguide shapes can be defined in terms of their path, or by specifying the upper and lower arms of the waveguide. Any waveguide shape that can be described by standard functions of a single variable can be entered.

Waveguides can be created and placed with a mouseclick or VB Script commands. Waveguides can be tapered in width and length in the X-Z plane, and height in the Y axis. Waveguides can be tapered in thickness, channel waveguides can be tapered linearly, and fibers can be tapered linearly or proportionately.

### Import from AutoCAD DXF and GDSII File Formats

Import and export to and from these standard mask layout formats is supported in OptiBPM. Once you have designed and simulated your waveguide circuit in OptiBPM, you can export the optimized design as a mask for fabrication.

### Fiber Vector and LP Mode Solver

Mode solvers based on a mesh can have limitations unacceptable for optical fiber calculations. The magnitude of the fields far from the fiber core can be orders of magnitude smaller than the error made in meshed simulations. Over long propagation distances those small fields can still be significant. OptiBPM has a multi-layer fiber mode solver that uses a transfer matrix technique, instead of meshes, for LP and fiber vector modes. Accurate estimation of the field over many orders of magnitude is possible.

### Advanced Optimization Algorithms

A good design can be obtained with physical insight and knowledge of basic design principles. However, finding the best design usually involves a tedious phase of optimization. OptiBPM has Optimization Algorithms that fully automate this important step. OptiBPM uses well established algorithms such as the Golden Search for one dimension and the Simplex method or Direction Set methods for multidimensional searches.

### Analysis of Large Scale Optical Circuits

BPM techniques work on a microscopic level (typically the smallest distance is about 0.1 μm), but photonic circuits, on the other hand, can occupy an entire wafer (scale: 10 cm). A successful analysis needs to combine the basic microscopic techniques with an approach at a more abstract or system level. OptiBPM has the Scattering Data feature, in which the Transfer Matrix of any device can be obtained. Once characterized this way, the device (a subsection of the layout of the entire optical circuit) can be uploaded to OptiSystem. The analysis of the optical circuit as an optical system is very efficient, enabling design of advanced photonic circuits such as Lattice Filters, Interleavers, Ring-Coupled Resonators, and AWGs.

### Electro-Optic Simulation

OptiBPM can simulate the linear electro-optic effect (Pockels Effect). You can make electrodes of any shape and add them to the layout. OptiBPM will calculate the static (or radio frequency) electric field in the transverse plane and calculate the optical propagation modified by the electro-optic effect.

### No Additional Modules to Purchase

- Includes robust 2D/3D Mode Solvers
- GDSII and DXF output mask formats
- XP/Vista and Windows 7 Compliant

**Interface with Popular Design Tools and Measurement Equipment**

### OPTIMODE

OptiMode is a complete software suite dedicated to the modal analysis of waveguides, which is the first job in optical component design. Any waveguide can be analyzed by a number of numerical algorithms, and many levels of analysis are possible, including: scalar, semi-vector, full vector, electric formulation, magnetic formulation, isotropic, and anisotropic. The waveguide design can be parameterized, and optimized. Complex waveguides (such as photonic crystals) can be created with VB Scripts written in either OptiBPM or OptiFDTD. The copying of profiles and materials (by simple drag-and-drop) between OptiMode, OptiBPM and OptiFDTD is permitted as they all share the same Profile Designer. Post processing and review of simulation data is accomplished using OptiMode Analyzer.