BS ISO 15368:2021

What is ISO 15368 about?  

ISO 15368 specifies rules for the measurement of the spectral reflectance of plane surfaces and spectral transmittance of plane parallel elements using spectrophotometers. 

ISO 15368 specifies spectrophotometric methods which are basic and normal and are extensively used for measurements and provides data over a wide range of wavelengths. 

Note 1: ISO 15368 does not apply to measurements of diffuse transmittance and reflectance.  

Note 2: ISO 15368 is applicable to test samples, which are coated or uncoated optical components without optical power. 

Who is ISO 15368 for? 

ISO 15368 on optics and photonics is relevant to: 

• Manufacturers of optical equipment 
• Manufacturers of photographic devices 
• Astronomical observatories 

Why should you use ISO 15368?  

Measurements of reflectance and transmittance using spectrophotometers are the most fundamental methods for the characterization of optical components. Since the spectrophotometric methods are basic and normal, they are extensively used and provide measurement data over a wide range of wavelengths. Optical components are characterised by measuring reflectance and transmittance using spectrophotometers that provides data with high reproducibility and repeatability. 

Rules for measurement under ISO 15368 help with right measurement techniques for assessing reflectance of plane surfaces and transmittance of plane parallel elements. This helps with producing optical equipment that offer high level of accuracy and precision.  

What’s changed since the last update?  

BS ISO 15368:2021 supersedes BS ISO 15368:2001 which is withdrawn. The main changes are: 

• Descriptions of the use of Fourier transform spectrometer instruments have been expanded and added wherever appropriate to an equivalent level as those of monochromatic instruments 
• The term “light” has been replaced with “optical radiation” to reflect that the standard’s spectral range extends beyond the visible