激光粒度仪

马尔文用户手册定义：
The obscuration is simply the fraction of light “lost” from the main beam when the sample is introduced. For example, an obscuration of 30% means that 30% of the incident laser beam (recorded during the Measure Background step) has been lost through scattering or absorption.

Obscuration – this helps the user to set the concentration of the sample when it is added to the dispersant. It is a measure of the amount of laser light lost due to the introduction of the sample into the analyser beam.

The obscuration term can be expressed mathematically:

Ob = 1 - Ls/Lb

Ls is the light intensity measured in the central detector when a sample is present in the cell, Lb is the same but with clean dispersant (i.e. with no sample).

Obscuration is usually expressed as a percentage: 100 x Ob. An ideal range is between 3 and 20%, depending on the sample and dispersion
unit used.

遮光度是指测量每次激光光束中有多少样品，如果太高可能发生多重衍射，如果太低会显示不足的信号并且精确度受到影响；

遮光度是不是就是遮光比？

遮光度我的理解就是遮光比

用通俗的话讲，遮光比就是样品在介质中分散后的浓度，这与样品加入的量有直接关系。我们是通过准确称量来控制的。

遮光比是指样品在介质中分散后的浓度，与样品加入的量有直接关系，加入量大遮光比就大。一般控制10-20%为好。

就是颗粒浓度