The LB-550 measures particle size from 1nm to 6µm and a concentration range from ppm up to 40% solids, all in as little as 30 seconds, making it ideally suited to a wide range of applications. Unlike traditional PCS-type instruments, most samples can be measured without dilution which can affect dispersion conditions and cause agglomeration.

With a standard analysis time of on to two minutes, the LB-550 is the fastest and most flexible particle size analyzer for the nanometer range of sizes. The Fourier-Transform/Iterative Deconvolution technique provides accurate results not only for average particle size, but also for distribution shape and identification of multiple modes, all without operator selections, a feature not found in most Photon Correlation Spectroscopy (PCS) instruments. Elimination of the need to select from alternative models and evaluating fitting errors provides confidence in the results and faster data analysis.

The temperature-controlled cell holder has a range of 5-70 degrees C for samples where size may change with temperature. Standard removable glass or disposable plastic curvettes are used to eliminate sample cross-contamination, ease cleaning and improve usability. Cells are available for sample volumes from 0.1-15ml. For high concentration samples where viscosity may affect results, a built-in viscometer option is available to provide accurate measurements at the time of analysis.


  • Wide Size Range: Accurate particle size measurements from 0.001-6µm.
  • Fast Analysis: The highly-refined optical design and algorithm provides measurement results in as little as 30 seconds, with class-leading accuracy and precision.
  • Wide Concentration Range: From 1ppm to 40wt%, depending on the sample.
  • Powerful Software: The LB-550 software package combines a number of useful data handling tools, and easy-to-use operator interface, and informative instrument control features. A Real-Time Display, batch operations, database searching, three-dimensional display of up to 300 measurement results, and summary reports allow for full control and analysis of the data. The user interface, print layout, and export functions are fully user-configured to provide the specific information required by each user.
  • Temperature Control System: Temperature Control System : The temperature-controlled cell holder has a range of 5-70 degrees C for samples where size may change with temperature. Temperature sensors in the cell holder and in the cell cap monitor and control the temperature to avoid fluctuations.
  • Ease of Use: With the built-in automation of the sampling systems and software, particle size analysis can be reduced to a single-button operation.

Manufactured by HORIBA


Principle of Operation

The LB-550 uses Dynamic Light Scattering measurements to measure particle size over the range of 0.001-6µm. The Brownian motion of the particles causes a Doppler shift in the incident light frequency. The amount of frequency shift is related to the frequency of the Brownian motion, wich is related to the size of the particles.

The LB-550's optical design uses a highly sensitive photo multiplier tube to be able to measure the lower concentrations. The optical arrangement which captures only the 180-degree scattered light, allows the light beam to be focused a short distance inside the cell, limiting the maximum amount of scattered light. This allows the measurement of high concentration samples without overloading the detector For more information on dynamic light scattering, visit our technique page.


Integrated Viscometer Version: For unknown samples, an integrated viscometer version is available to directly measure and compensate for variations in viscosity which can significantly affect the measurement results.

Pharmaceutical Regulation Compliance: A 21CFR part 11 compliant software package is available, as well as a full instrument validation package.