Active Standard ASTM C1426 | Developed by Subcommittee: C14.04
Book of Standards Volume: 15.02
Historical (view previous versions of standard)
This practice covers the standards for the verification and calibration of polarimeters required to maintain these instruments and ensure that the optical setup is within specification for satisfactory measurements. Verification and calibration procedures are performed using two types of procedures: Procedure A (verification) and Procedure B (calibration). Procedure A is done by measuring individual components and their orientation to ensure that they comply accordingly. Procedure B is done by determining the accuracy of the polarimeter using a calibrated gage or retarder.
This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.
1.1 Polarimeters and polariscopes used for measuring stress in glass are described in Test Methods F218, C148, and C978. These instruments include a light source and several optical elements (polarizers, optical retarders, filters, and so forth) that require occasional cleaning, realigning, and calibration. The objective of these practices is to describe the calibration and verification procedures required to maintain these instruments in calibration and ensure that the optical setup is within specification for satisfactory measurements.
1.2 It is mandatory throughout these practices that both verification and calibration are carried out by qualified personnel who fully understand the concepts used in measurements of stress retardation and are experienced in the practices of measuring procedures described in Test Methods F218, C148, and C978.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
C148 Test Methods for Polariscopic Examination of Glass Containers
C162 Terminology of Glass and Glass Products
C770 Test Method for Measurement of Glass Stress--Optical Coefficient
C978 Test Method for Photoelastic Determination of Residual Stress in a Transparent Glass Matrix Using a Polarizing Microscope and Optical Retardation Compensation Procedures
F218 Test Method for Measuring Optical Retardation and Analyzing Stress in Glass
ICS Number Code 71.040.10 (Chemical laboratories. Laboratory equipment)