BS EN ISO 11551:2019

What is ISO 11551 - Absorptance of optical laser components about?  

ISO 11551 assists you in calibrating the power signals by placing the calibrated laser power detector. With the help of measuring arrangements, you can categorically determine the absorptance of optical components.  

ISO 11551 specifies procedures and techniques for obtaining comparable values for the absorptance of optical laser components.  

Who is ISO 11551 - Absorptance of optical laser components for? 

ISO 11551 on absorptance of optical laser components is useful for: 

• Manufacturers of electronic devices 
• Manufacturers of laser devices 
• Electrical engineers  
• Personnel of research laboratories 

Why should you use ISO 11551 - Absorptance of optical laser components?  

To characterize an optical component, it is important to know its absorptance. When radiation impinges upon a component, a part of that radiation is absorbed, increasing the temperature of the component. In ISO 11551 the part of the absorbed power/energy, that is converted into heat, is measured. If enough energy is absorbed, the optical properties of the component can change, and the component can even be destroyed. Absorptance is the ratio of the radiant flux absorbed to the radiant flux of the incident radiation. In the procedures described in ISO 11551, the absorptance is determined calorimetrically as the ratio of power or energy absorbed by the component to the total power or energy, respectively, impinging upon the component. The assumption is made that the absorptance of the test sample is constant within the temperature fluctuations experienced by the component during the measurement. For most optical bulk materials, the absorptance depends on the position of the irradiating beam on the sample surface. Several infrared materials exhibit a strong dependence of absorptance on temperature, especially at high temperatures. 

The evaluation of absorptance of optical laser components is possible by determining the components that are heated during irradiation by a weighing machine.  The calculation method of absorptance is mentioned in ISO 11551 useful in analysing the calorimetric data with respect to the possible occurrence of temperature drift phenomena.   With ISO 11551 you can achieve test methods that help in determining the values absorptance of optical laser components to demonstrate that laser calorimetry can be a reliable and sensitive characterization tool to be used by industries.  

What’s changed since the last update?  

BS EN ISO 11551:2019 supersedes BS EN ISO 11551:2003. BS EN ISO 11551:2019 includes some technical changes with respect to BS EN ISO 11551:2003. These include: 

• Clause 4: The table for symbols and units was corrected 
• Clause 5: More detailed specifications of environmental conditions for UV- and IR applications are provided in the second paragraph. ISO 7 specification was deleted 
• In 7.2.3: In the first paragraph, the calibration procedure is specified in more detail, including the consideration of the heating scheme for thick samples 
• In A.1: “irradiation dose” added as influencing parameter 
• In A.3: Generalization of nonlinear absorption dependencies