Your instrument. In motion.
Choose your parts. Shape the beam. Watch the fields respond.
Instrument controls
LIVEA source of electrons
A tungsten filament, a negative cathode, and a grounded anode.
Heating sets emission. Acceleration voltage sets electron energy. The heater floats at cathode potential.
Shape & steer
Aperture, magnetic lens, and two pairs of electrostatic scan plates.
Make room for the beam
Roughing pump → backing line → turbomolecular pump → column.
The specimen is the sensor
Insulated holder → LMC662 → ADS1115 → ESP32.
Readout & specimen assumptions
The specimen sits on an insulating support but stays near 0 V through amplifier feedback. Its net current passes through a sealed electrical feedthrough to the shielded PCB.
Start slowly and calibrate the blanked-beam baseline. Fine butterfly-wing detail remains an experimental goal.
Collection & material assumptions
The detector stays inside the evacuated chamber, with a clear vacuum path to the specimen. A and K cross sealed electrical feedthroughs to the external bias supply and current amplifier.
Bias is across the diode: A = −Vᴿ, K ≈ 0 V. The surrounding chamber stays at ground. The current-to-voltage amplifier is a proposed circuit.
Physics, as you change it.
Hover, focus, or select an equation for its derivation, assumptions, and original sources.
Follow the current.
Trace the supplies, compare potentials, and inspect every measurement.
Insulated specimen, sealed feedthrough, guarded current amplifier, bipolar signal conditioning, external ADC and ESP32 connections.
Select a meter to inspect it; double-click to zoom. Or choose a component above. Drag to pan; scroll to zoom. Circuit colors identify connections; the microscope’s RGB fields show strength.
Virtual instrumentation. Voltage probes compare two nodes in parallel; current probes are in series. Loading is omitted. Gauge readings and scope traces come from the simulation, and the schematic shows functional connections rather than a component pinout.
Grounded aperture by default. A shared anode/aperture potential gives zero mean gap field, with local fringe shapes only illustrated. Optional aperture bias changes the field overlay; aperture-lens focusing is not solved. Beam blanking does not disable the indicated electrode potentials.
The electrical relationships.
Build from your BOM.
Edit the source files, research missing specifications, and keep every setup reproducible.
Select a component
| Reference | Part / value | Manufacturer | Quantity | Source status |
|---|
Start from a known setup.
Snapshots keep the exact parameters and scan code from that run, independently of later BOM changes.
Write the scan.
Design a trajectory, preview it, and inspect the ESP32 control program.
DAC80502 · 16-bit
From vacuum to signal.
An interactive operating sequence. Each step explains what changes and what to observe.
What this project already provides
The repository contains a low-voltage controller for an external Spellman UM6N4 acceleration supply. The floating filament supply, gun, column, vacuum equipment, lenses, scan amplifiers, and detector are additional systems. The ESP32 scan example is a proposed extension, separate from the existing analog acceleration controller.
This sequence is a learning aid. Actual setpoints, pump crossover, heater ratings, isolation, grounding, HV discharge, and interlock commissioning come from the selected equipment and the project’s engineering report.
Every equation has a source.
Live substitutions, derivations, and the limits of the model. Select any equation to explore.
Relativistic beam kinematics, a steady-state filament heat balance, ideal vacuum dynamics, paraxial optics, and a synthetic detector signal. The display uses schematic geometry and slows electron motion. Numerical readouts use SI conversions. Current, counts, and SNR equations describe the available beam and a proposed exposure; manual blanking stops acquisition. Electric-field values include the current X scan command plus alignment offset. Material contrast, coil geometry, aberrations, and emission acceptance are illustrative assumptions, not measured performance.
Current balance, transimpedance, electronic noise and ADC timing are separated from assumed specimen contrast. Hover an equation for its derivation and sources.