ASTM C1426-14

Standard Practices for Verification and Calibration of Polarimeters

ABSTRACT
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.
SCOPE
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.

General Information

• Status: Historical
• Publication Date: 30-Apr-2014
• ICS: 71.040.10 - Chemical laboratories. Laboratory equipment
• Technical Committee: C14 - Glass and Glass Products
• Drafting Committee: C14.04 - Physical and Mechanical Properties

Relations

• Replaces: ASTM C1426-09 - Standard Practices for Verification and Calibration of Polarimeters
• Effective Date: 01-May-2014
• Replaced By: ASTM C1426-14(2020) - Standard Practices for Verification and Calibration of Polarimeters
• Effective Date: 01-Aug-2020
• Referred By: ASTM C770-16(2020) - Standard Test Method for Measurement of Glass Stress—Optical Coefficient
• Effective Date: 01-May-2014
• Referred By: ASTM F218-13(2020) - Standard Test Method for Measuring Optical Retardation and Analyzing Stress in Glass
• Effective Date: 01-May-2014
• Referred By: ASTM C148-17(2022) - Standard Test Methods for Polariscopic Examination of Glass Containers
• Effective Date: 01-May-2014

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:C1426 −14
Standard Practices for
1
Verification and Calibration of Polarimeters
This standard is issued under the fixed designation C1426; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3. Terminology
1.1 Polarimeters and polariscopes used for measuring stress 3.1 For definitions of terms used in these practices, see
in glass are described in Test Methods F218, C148, and C978. Terminology C162.
These instruments include a light source and several optical
4. Principles of Verification and Calibration Procedures
elements(polarizers,opticalretarders,filters,andsoforth)that
4.1 Verification and calibration of polarimeters are accom-
require occasional cleaning, realigning, and calibration. The
plished using the following procedures:
objective of these practices is to describe the calibration and
4.1.1 Procedure A: (Verification)—Measureindividualcom-
verification procedures required to maintain these instruments
ponents and their orientation to ensure that the requirements of
in calibration and ensure that the optical setup is within
Test Methods F218, C148, and C978 are satisfied.
specification for satisfactory measurements.
4.1.2 Procedure B: (Calibration)—Determine the accuracy
1.2 It is mandatory throughout these practices that both
of the polarimeter using a calibrated gage or retarder.
verification and calibration are carried out by qualified person-
nelwhofullyunderstandtheconceptsusedinmeasurementsof
5. Auxiliary Component Requirements
stress retardation and are experienced in the practices of
5.1 The following are required to verify and calibrate a
measuring procedures described in Test Methods F218, C148,
polarimeter:
and C978.
5.1.1 Verification of Components (Procedure A):
1.3 The values stated in SI units are to be regarded as 5.1.1.1 Verification of Polarization Effıciency, a light-
standard. No other units of measurement are included in this
intensity meter, linear over the range of measured values.
standard. 5.1.1.2 Verification of Quarter-Wave Plate, a Babinet com-
pensator equipped polarimeter, with a monochromatic light
2. Referenced Documents
source of traceable wavelength.
2
5.1.1.3 Reference Polarizer with Known Axis.
2.1 ASTM Standards:
5.1.2 Calibration of Polarimeter (Procedure B):
C148Test Methods for Polariscopic Examination of Glass
5.1.2.1 Procedure B requires a gage with a calibrated,
Containers
known retardation. The calibrated gage must have sufficient
C162Terminology of Glass and Glass Products
retardation to calibrate the instrument within its intended use
C770Test Method for Measurement of Glass Stress—
range. For example, a polariscope/polarimeter used in Test
Optical Coefficient
Methods C148 should be calibrated using a gage exhibiting a
C978Test Method for Photoelastic Determination of Re-
retardation range of from 0 to 227 nm (0 to 10 temper grade).
sidual Stress in a Transparent Glass Matrix Using a
5.1.2.2 Alternately, a rectangular cross-section specimen
Polarizing Microscope and Optical Retardation Compen-
prepared from an SRM glass having a known stress-optical
sation Procedures
constant, subjected to uniaxial compression in a calibrated
F218Test Method for Measuring Optical Retardation and
testing machine, may be used instead of a calibrated gage with
Analyzing Stress in Glass
known retardation.
6. Verification and Calibration Procedures
1
These practices are under the jurisdiction of ASTM Committee C14 on Glass
and Glass Productsand are the direct responsibility of Subcommittee C14.04 on 6.1 Procedure A—Verification and Aligning of Components:
Physical and Mechanical Properties.
6.1.1 Verification of Polarization Effıciency—Using a light-
Current edition approved May 1, 2014. Published May 2014. Originally
intensity meter, measure the light intensity, with polarizers
approved in 1999. Last previous addition approved in 2009 as C1426–09. DOI:
crossed, I (dark field) and then with polarizers parallel, I .
10.1520/C1426-14. c p
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Calculate the polarization efficiency, E, as follows:
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
~I 2 I !
Standards volume information, refer to the standard’s Document Summary page on p c
E 5 (1)
the ASTM website. I
p
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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C1426−14
The efficiency must satisfy the requirements of the test ods F218). Repeat five times and calculate the average retar-
method for whic
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C1426 − 09 C1426 − 14
Standard Practices for
1
Verification and Calibration of Polarimeters
This standard is issued under the fixed designation C1426; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
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
2
2.1 ASTM Standards:
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
3. Terminology
3.1 For definitions of terms used in these practices, see Terminology C162.
4. Principles of Verification and Calibration Procedures
4.1 Verification and calibration of polarimeters are accomplished using the following procedures:
4.1.1 Procedure A: (Verification)—Measure individual components and their orientation to ensure that the requirements of Test
Methods F218, C148, and C978 are satisfied.
4.1.2 Procedure B: (Calibration)—Determine the accuracy of the polarimeter using a calibrated gage or retarder.
5. Auxiliary Component Requirements
5.1 The following are required to verify and calibrate a polarimeter:
5.1.1 Verification of Components (Procedure A):
5.1.1.1 Verification of Polarization Effıciency, a light-intensity meter, linear over the range of measured values.
5.1.1.2 Verification of Quarter-Wave Plate, a Babinet compensator equipped polarimeter, with a monochromatic light source of
traceable wavelength.
5.1.1.3 Reference Polarizer with Known Axis.
5.1.2 Calibration of Polarimeter (Procedure B):
1
These practices are under the jurisdiction of ASTM Committee C14 on Glass and Glass Productsand are the direct responsibility of Subcommittee C14.04 on Physical
and Mechanical Properties.
Current edition approved Nov. 1, 2009May 1, 2014. Published January 2010May 2014. Originally approved in 1999. Last previous addition approved in 2004 as
C1426–99(2004).2009 as C1426–09. DOI: 10.1520/C1426-14.
DOI: 10.1520/C1426-09.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
C1426 − 14
5.1.2.1 Procedure B requires a gage with a calibrated, known retardation. The calibrated gage must have sufficient retardation
to calibrate the instrument within its intended use range. For example, a polariscope/polarimeter used in Test Methods C148 should
be calibrated using a gage exhibiting a retardation range of from 0 to 227 nm (0 to 10 temper grade).
5.1.2.2 Alternately, a rectangular cross-section specimen prepared from an SRM glass having a known stress-optical constant,
subjected to uniaxial compression in a calibrated testing machine, may be used instead of a calibrated gage with known retardation.
6. Verification and Calibration Procedures
6.1 Procedure A—Verification and Aligning of Components:
6.1.1 Verification of Po
...