Sequoia Scientific manufacturer the LISST series of size analysers designed for field use.


The array of instruments originated with applications in the marine environment, but now includes stream-gauging, paper emulsifier optimzation, airborne cloud dropet measurements and others still in development.

LISST particle sizer

Sequoia is the sole manufacturer of the LISST series laser sediment/particle/bubble/droplet sensing instruments, compliant with the ISO-13320 standard. Some of these instruments deliver the optical volume scattering function (VSF) of interest to optical oceanographers. The products are fully submersible and some are non-submersible instruments. All employ the small-angle forward scattering principle, also called low-angle laser scattering or laser diffraction.


LISST stands for Laser In Situ Scattering and Transmissometry.

A slide show on YouTube describes the laser diffraction technology used in LISST instruments, as well as some common applications for the most popular LISST particle sizers


follow the links for more information on Sequoia Products
LISST Submersible LISST_sediment systems
LISST_100X LISST_Portable
LISST_25X LISST_Streamside & LISST_Infinite