An instrumental system based on a two-dimensional detector to measure electron number densities in plasmas is described. High-resolution H spectra are detected simultaneously at up to 200 spatial locations. Radially resolved electron number densities are determined, following Abel inversion and comparison of H line profiles to theoretical Stark-broadened spectra. The particular interpolation procedure used to calculate H spectra from discrete literature data can affect the calculated electron number density values. Radially and vertically resolved electron number maps for inductively coupled plasmas supported in Fassel-type and low-flow torches are presented, Electron number densities in the center of the 1.0-kW ICPs are less than 2.5 × 10¹⁴ cm⁻³. Short-term precision is better than 1% relative standard deviation except low in the center of the plasma, where the H intensity is low on-axis and larger off-axis.

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription