1. Device overview:

This document summarizes essential details for materials, setup, and operation. This is for transcription, archival, and research purposes only. It is based on an old patent and is not intended as a finished product. Operating conditions described require specialized handling and safety precautions, and the descriptions outlined here do not constitute a recommendation or endorsement to build or operate the device. Attempts to replicate or build upon these models are entirely at your own risk.

Source patent:

• Shoulders, Kenneth R. U.S. Patent No. 5,123,039. Issued June 16, 1992.
• Image: Figure 1 and 2 on sheet 1 (page 3)
• Text: FROM page 44 column 7 line 24 UNTIL page 44 column 8 line 33

1.1. Purpose

Basic Function:
Produces EV entities via high-voltage field emission from a pointed cathode tip in a controlled environment.

Core Behavior:
A fast-rise negative high-voltage pulse (~–10 kV) applied to a tungsten cathode initiates field emission. EVs are generated near the cathode tip and travel toward a grounded anode across a dielectric plate, leaving "optically visible" traces in the dielectric it travels across (and marks when impacting a witness foil).

Scale & Format:
Intricately small device to be used in a low pressure or vacuum chamber. Typical component dimensions are ~10 mm.

1.2. Components

Diagram(s):
See images provided.

Parts list:

Conditionals:

1. Witness plate is entirely optional.

Physical Arrangement:
Cathode suspended above dielectric plate with tip (12a) pointing toward it. Anode is located beneath dielectric, witness plate beneath that. Enclosure houses all components and maintains vacuum or gas environment.

Assembly Notes:
Cathode must be well-sharpened and aligned. Use HV-compatible feedthroughs. Dielectric and witness plate should be rigidly held.

1.3. Behavior & Observations

Expected Behavior:
A pulse to the cathode generates EVs that traverse the dielectric surface, leaving visible trails and potentially impacting a witness plate. EVs follow fine structural features and may deviate from straight paths due to prior surface charging.

Notes:

• Dielectric charging alters future paths.
• Visible tracks suggest surface modification or optical property change.
• Multiple EVs may be generated under certain conditions.
• Impact location on witness foil is likely unique per shot due to localized discharge effects.

2. Device materials and environment

2.1. Materials

Suggested Materials:

• Cathode: Tungsten rod, 1 mm diameter, sharpened
• Dielectric: Quartz plate
• Anode: Tungsten plate
• Witness Plate: metal foil, or other desired/interesting targets (like nuclear emulsions)

Availability:
Standard lab materials; all components are readily sourced from electronics or vacuum suppliers. Welding rods and quartz slides can be substituted for prototyping.

2.2. Operating Conditions

Electrical:

• Cathode Pulse: –10 kV, fast rise (ns–μs)
• Anode: Grounded or slightly positive
• Idle Voltage: Cathode held at same potential as anode (0V or +V)

Environment:

• Vacuum (~10⁻³ torr) or low-pressure inert gas
• Room temperature

2.3. Equipment

• HV pulse generator
• Vacuum pump + chamber with HV feedthroughs

2.4. Operation notes

• Pre-align cathode tip and dielectric surface
• Confirm vacuum integrity before pulsing
• Discharge dielectric surface periodically if using repeated pulses

3. Additional information

3.1. Additional information

• Refractory metals preferred for durability under repeated pulses
• Highly dielectric separators are preferred

3.2. Attachments

• Annotated screenshots of FIG. 1 & 2 overlaid on model
• Screenshot of STL model
• FreeCAD model including annotation
• FreeCAD model without annotation
• STL of model