Noble Gas Ion Lasers (or simply Ion Lasers) are used across a variety of markets and support a number of critical processes such as lithography for semiconductor manufacturing, microscopy applications and Raman spectroscopy, and lasers for medical applications such as flow cytometry.


How ion lasers work

An active laser medium is contained within a sealed glass tube called a plasma tube or glow discharge tube which is manufactured from borosilicate glass, precisely formed into the required shape. It is then vacuum evacuated, backfilled with a high-purity gas (argon, for example), and sealed to ensure long laser life. Active laser mediums (or lasing mediums) are typically argon or krypton gas, but may also include Ar/Kr or other gas mixtures which yield different output wavelengths and power levels.

A high current discharge ionizes the gas, causing excited electrons to move to higher energy states. When they return to their base state, they emit coherent photons of the same wavelength.  Electrons can then be returned to their base state by hitting them with another pulse of current.

Two mirrors, one on either side of the plasma tube, reflect the majority of emitted photons back through the tube, which multiplies the number of electrons moving to higher and lower energy states, further multiplying the number of coherent photons and energy level of the output. One of these mirrors allows a small percentage of the photons (e.g. 0.1%) to pass through the mirror creating the external laser beam of photons.


Key features to consider when selecting a plasma tube or glow discharge tube supplier for your ion laser

  • Fill Capabilities: Ensure that the glass tube is vacuum evacuated and backfilled with the appropriate noble gas or gas mixture at the appropriate vacuum level to ensure that the concentration, purity, and volume of gas meets the laser criteria.
  • Leak Tightness: Ensure that the ampoule supplier can reliably seal and entrap the noble gas appropriate for your ion laser design.
  • Shape: Partner with a supplier who can meet the plasma tube design tolerances for your laser.
  • Packaging: Specify packaging material appropriate for your required lot sizes and environmental conditions. Anti-static packaging may be required to ensure quality from supplier to installation.
  • Price: Volumes and manufacturability can significantly reduce the costs of noble gas-backfilled glass tubes. Look for a supplier who has the experience and expertise to support your team of experienced engineers.