Neutral Density Filters

PRODUCT ENQUIRY FURTHER PRODUCT INFORMATION & HOW TO ORDER These references can be used to qualify the absorbance accuracy and linearity of visible spectrophotometers with a spectral bandwidth of 6.5 nm or less, over the wavelength range 440 -635 nm. Measurements made with these references will be accepted as evidence of instrument qualification by: United States Pharmacopoeia American Society for Testing and Materials Therapeutic Goods Administration (Australia) British Pharmacopoeia Schott NG-type glasses have been used for over thirty years for the validation of the absorbance scale and linearity of spectrophotometers in the visible region. Filters with a wide range of transmission and absorbance values can be produced.
The spectrum of these filters is essentially flat over the range of calibration. A range of 18 filters is available from Starna, covering absorbance values from approximately 0.04 A to 3.5 A, calibrated at 440 nm, 465 nm 546.1 nm 590 nm and 635 nm.

A Certificate of Calibration and Traceability and full instructions for use are provided with each Reference Material. Starna Scientific is accredited to both ISO 17034 (4001) as a Reference Material producer, and ISO/IEC 17025 (0659) as a Calibration Laboratory for optical reference measurements. Starna offers a Lifetime Guarantee on all its Reference Materials.

Neutral Density Filter