Small but Perfect – Starna Short Path Cells

A range of spectrophotometer cells with precisely controlled path lengths down to 8 microns are available from Starna. These cells are ideal for the measurement of low transmittance samples when dilution is not an option.

To achieve the necessary accuracy required, path length is measured by NIR interferometry. Using this technique, absolute path lengths in the range of 8 – 200 μm, can be measured with an uncertainty budget of ± 0.2 μm. This is an order of magnitude better than is achievable using mechanical measurement techniques. Like all Starna cells, they are manufactured in an ISO 9001:2000 environment meeting the latest ISO 9001 standard. Windows are in UV grade quartz and the cells are available in fully fused, demountable and flow cell formats. They can be used in any conventional spectrophotometer.

An example is the Starna 20/C/0.008 cell, designed for use with the Australian/New Zealand standard (AS/NZS 2604:1998) for Sunscreen products. This standard requires that the sample is measured, direct and undiluted, in an 8 μm path length cell.