Sequoia Scientific


Flow-Through Automated Scattering Measurement

The LISST-Horizon is a self-contained instrument for bench-top deployment in a research vessel laboratory.

Plumbed to continuous underway uncontaminated seawater, it measures optical scattering and beam attenuation.

A first prototype has been delivered to NASA (see our News release).

For further information, contact us!


  • Automated deployment in flow-through seawater systems, including clean water backgrounds, cleaning, and scattering standard measurement
  • Mixers in the sample chamber to keep particles suspended during measurement
  • Automated filtered sample background using attached external particle filter (0.2 μm)
  • Measures near-forward (0.1-15°, 36 log-spaced detectors) and side scattering (35-150°, 24 detectors) from a 520 nm laser source
  • Beam attenuation from proven LISST-200X optics, with extended pathlength for application to offshore waters
  • Raw data stored internally and offloaded via ethernet for processing with provided MATLAB software


Parameters Measured

  • Optical scattering from 0.1 to 150°
  • Beam transmission
  • Sample temperature and fluidics parameters such as pressures and flow rate

Mechanical and Electrical

  • Dimensions: L = 67.4 cm x W = 37.5 cm x H = 29.3 cm
  • Weight: 19 kg
  • Laser: 520 nm solid state diode laser
  • External power input: 110/220 VAC converted to 24 VDC using provided power brick
  • Plumbing connections using 3/8 inch OD (1/2 inch for drain) tubing and push-to-connect fittings
  • External tanks for holding clean water for background, cleaning solution, and scattering standard; each with pressure sensor for monitoring tank level


LISST-Horizon Item # and Description

Item #DescriptionThumbnail
Self-contained instrument for bench-top deployment in a research vessel laboratory. Plumbed to continuous underway uncontaminated seawater, it continuously measures optical scattering and beam attenuation at 520 nm.
Tanks for rinsing, clean water and for reference measurements not included.
One-time service of instrument within 36 months after delivery.
Includes one-way return shipping from Sequoia, all evaluation, diagnosis, testing and calibration.
Parts and labor for repairs not included.
Must be purchased together with new instrument.
NOTE: End-user responsible for return shipment DDP to Sequoia.

LISST-Horizon Accessories *NOT* Included with Instrument

Item #DescriptionThumbnail
SEQ-AC-HORIZON-TANKLISST-Horizon Clean Water Tank w/Float ValveNo Picture.
SEQ-AC-HORIZON-TNK1LISST-Horizon Clean Water Tank w/o Float ValveNo Picture.
SEQ-AC-HORIZON-SCTKLISST-Horizon Standard Cleaner Solution TankNo Picture.
SEQ-AC-HORIZON-SPTKLISST-Horizon Standard Particle Tank No Picture.
SEQ-AC-HORIZON-JBOXLISST-Horizon Tank Junction BoxNo Picture.
SEQ-AC-HORIZON-ASCLISST-Horizon Accessories Ship CaseNo Picture.
SEQ-AC-HORIZON-FILLISST-Horizon replacement filters No Picture.


Can I rent the LISST-Horizon?

Yes. Sequoia has a rental unit available. The minimum rental period is one (1) month and the first month’s rent must be prepaid in full before the instrument is delivered. Subsequent months are invoiced at net 30 days payment terms. User must pay for the return shipping to Sequoia, and insure the instrument for the full price for the duration of the rental period as well as the return shipping.

If you decide to purchase a new instrument within 90 days after the return of the rental unit you can apply 85% of what you already paid in rental fees towards the cost of the new instrument.

Call for a draft rental agreement.