Getting Started
LensHH-LT runs on Windows, Linux, and macOS:
- Windows: download the Inno Setup installer and run it.
- Linux: download the AppImage, mark it executable, and run it.
- macOS (Apple Silicon): download the macOS package, unzip it, then right-click
LensHH-LT.app→ Open. Apple Silicon (M1 or later); CPU-only.
See the Download page for full details.
System Requirements
- Windows 10/11, Linux, or macOS (64-bit)
- .NET 8 Runtime (bundled with all desktop downloads — the Windows installer, Linux AppImage, and macOS package)
- 4 GB RAM minimum, 8 GB recommended
- Internet connection for activation (one-time). Offline activation available for air-gapped machines.
User Guide
Read the full, searchable user guide right in your browser, or download the PDF. The same guide is built into the application under Help → User Guide.
Open User Guide → Download PDF
Activation
Free Trial
To start a 45-day free trial:
- Open LensHH-LT
- Go to Help → Start Free Trial
- Enter your email address
- Check your email for a 6-digit activation code
- Enter the code in the application
The trial is full-featured with no limitations. One trial per email address, valid on one machine.
License Activation
After purchasing a license:
- Go to Help → Activate License
- Enter your license key (format:
LHLT-XXXX-XXXX-XXXX-XXXX) - Click Activate
Each license can be activated on up to 2 machines. To move a license, use Help → Deactivate This Machine on the old machine first.
Offline Activation
For air-gapped machines without internet access, use the CLI on any connected machine:
license fetch-token LHLT-XXXX-XXXX-XXXX-XXXX <machineId> token.json
Transfer token.json to the target machine, then:
license offline token.json
Lens Editor
The lens editor displays the optical system as a spreadsheet-style surface table. Each row represents one surface.
Surface Properties
- Radius — radius of curvature (mm). Use
Infinityfor flat surfaces. - Thickness — distance to the next surface (mm).
- Material — glass name (e.g., N-BK7) or MIRROR for reflective surfaces.
- Semi-Diameter — clear aperture half-diameter (mm).
- Conic — conic constant (0 = sphere, -1 = paraboloid).
Analysis
Available under the Analysis menu:
- Paraxial data (EFL, BFL, F/#, magnification, pupils)
- FFT MTF (vs. frequency, vs. field, vs. focus)
- Geometric MTF
- Spot diagrams
- Ray fans and OPD fans
- Distortion and field curvature
- Seidel aberration coefficients
- Relative illumination
- Lateral color and chromatic focal shift
- Wavefront maps
- FFT PSF
- System data
Optimization
Local Optimization
Damped least-squares (Levenberg-Marquardt) optimizer. Set variables on surfaces, define a merit function, and run Optimization → Local Optimization.
Multistart
Randomizes variables around the current solution and runs many short local optimizations in parallel. Finds the best result across all trials.
GPU pre-screen (beta). On Windows or Linux with a CUDA-capable NVIDIA GPU, Multistart can offload the candidate pre-screening pass to the GPU; the Levenberg–Marquardt refinement always runs on the CPU. Benefit varies by GPU.
Global Search
Explores the design space from many diverse seeds and returns a gallery of structurally distinct solutions rather than a single answer — near-duplicates are merged by merit so each card is a genuinely different lens form. Pick the form that best fits your packaging and aberration trade-offs, then polish it locally. Ideal early in a design when the best topology is still unknown.
Basin Hopping
Hooke-Jeeves direct search combined with LM polishing — good when the topology is fixed but the local minimum needs to be escaped.
Synthesis by Saddle-Point Construction
Grows the design one element at a time by finding saddle points in merit-vs-curvature space. Can insert single elements or cemented doublets, restricted to either side of the stop. Turns a single lens into a multi-element system in one run.
Split Element & Search Best Asphere Surface
Targeted topology growth: split the highest-aberration element into two glasses, or aspherize the surface that gives the most merit improvement.
File Formats
Native Format (.lhlt)
JSON-based format that preserves all data including merit function, variables, and constraints.
Import
- Zemax (.zmx) — surfaces, aspherics, conics, fields, wavelengths
- Code V (.seq) — surfaces, aspherics, conics, fields, wavelengths
- OSLO (.len) — surfaces, aspherics, conics, wavelengths
- Optalix (.otx) — surfaces, aspherics, conics, fields, wavelengths
- Optiland (.json) — surfaces, aspherics, conics, fields, wavelengths
Export
Export to all supported formats via File → Export As.
Command Line Interface
LensHH-LT includes a CLI for scripting and batch operations:
lenshh open mylens.lhlt
paraxial
fft-mtf
spot
optimize 500
save result.lhlt
Support
Email: support@synapseoptics.com