Cathodoluminescence – What is Cathodoluminescence?

Cathodoluminescence Equipment Sales -

Optical Cathodoluminescence Microscope Stage

Optical Cathodoluminescence MicroscopeOverview

CITL are specialists in Cathodoluminescence, the low cost way to analyse most materials. With Cathodoluminescence you can achieve the same information as with an Electron Microscope but at a fraction of the cost and time, as no special preparation is required.

The Optical Cathodoluminescence Stage can be mounted to most optical microscopes, whether transmitted or reflected light, with a large choice of techniques.

The chamber accepts both solid accepts both solid (to 15mm thick) and thin sections. The basic cathodoluminescence system can be enhanced by the addition of Optical Spectral Analysis (OSA) or Energy Dispersive X-Ray Spectrometry (EDX). Measurements of the same specimen position can be made with these analytical attachments when used concurrently.

Please ensure you read the equipment requirements.

Specifications

STAGE

  • Full movement and viewing – 70 mm x 50 mm sections
  • Sample thickness to 15 mm as standard

SAMPLE CHAMBER

  • Base window for transmitted light microscopy for standard polished geological sections
  • Vacuum manifold with automatic precision vacuum control valve
  • Solid-state pressure gauge, automatic vent valve, KF direct connection for vacuum pump
  • OPTIONS:

    • Chamber electron gun
    • Electrical feed-through
    • Spacer ring to increase sample thickness

CHAMBER TOP PLATE incorporating electron gun

Choice of TP5 or TP9 Top Plate included in standard unit (either Top Plate available as additional item):

  • TP5 with 5mm WD for objectives with 2.5 X and above magnification
  • TP9, larger window top plate with 9 mm WD for objectives from 1 X and above

MICRO-CONTROLLED ELECTRONICS UNIT

  • Gun supply – 4kV to 30kV and 20uA to 2mA. Gun current, voltage electronic/vacuum stabilised
  • Controls – Pre-select gun voltage, gun current values
  • Switch select – Insert sample, operate mode: automatic or manual, gun voltage on/off
  • Alpha numeric display – Gun voltage, gun current, vacuum, operating mode and state, diagnostics for all internal power supplies, control values
  • PC interface – RS 232
  • Preset controls – Gun power, voltage limit, current limit, display auto brightness
  • Indicators – Vacuum pump, vacuum ready, kV on, gun supply limits, vacuum control valve operation
  • Gun safety – Interlock to vacuum, external link present
  • Options – Two auxiliary power supplies

VACUUM

  • Precision automatic control valve, automatic vent valve. Input port air, helium, argon or other gas
  • Measurement – solid-state pressure gauge, indication – alpha- numeric display
  • Operation – touch switch, automatic vacuum controlled gun high voltage & current – vent
  • Interlock to high voltage

POWER REQUIREMENTS

  • Electronics 85-265V AC 50-100HZ 150VA max
  • Switched vacuum pump load 850VA max (voltage to be specified when placing order)
  • Total load 1000VA

TECHNIQUE OPTIONS

  • Analytical top plate with solid state peltier cooled X-ray detector for EDX
  • Optical spectroscopy

Technical Diagrams

Optical Cathodoluminescence Microscope Stage - Side View

Optical Cathodoluminescence Microscope Stage - Side View

Optical Cathodoluminescence Microscope Stage - Side View

Requirements

Microscope Considerations

  • Lenses need to have a minimum working distance (W.D.) of 5mm (TP5 Top Plate) or 9mm (TP9 and ATP). Max W.D. should be as close to Minimum W.D. as possible
  • Lenses with a large numerical aperture are preferred. Cathodoluminescence is an intrinsic property and extra brightness cannot be obtained simply by increasing electron current or kV without damaging the sample. So Lenses should be as close to the observation window with as large an N.A. as possible so that maximum light is collected
  • Microscopes should have the minimum number of filters in the observation path
  • Collection (camera) ports should offer a 100% transmission option to achieve minimum collection times
  • Digital camera requirements are similar to those for fluorescence microscopy and a cooled camera is preferred
  • The microscope stand should be as sturdy as possible and the stage must be able to take the weight of the chamber (4.5Kg in the Z axis) without showing any focus drift

CL Room

  • Because Cathodoluminescence is a low light intensity it is necessary for the room in which the unit is installed to have black out facilities. Whilst bright samples can be viewed in normal light, most samples require a darkened or blacked out room
  • A room vent is recommended
  • Whilst air conditioning is not a must, the conditions in the room should not exceed Temperature Range +10 to +30 deg C
  • Rel Humidity Max 70% non-condensing (storage must be non-condensing)
  • The Mains electricity supply must include a Clean Ground reference