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GB/T 7962 consists of 23 parts under the general title Test method(s) of colourless optical glass or Colourless optical glass test methods:
——Part 1: Refractive index and coefficient of dispersion;
——Part 2: Optical homogeneity - Fizeau plano-interferometry;
——Part 3: Optical homogeneity - Holographic interferometry;
——Part 4: Temperature coefficient of refractive index;
——Part 5: Stress birefringence;
——Part 6: Young's modulus, shear modulus and Poisson's ratio;
——Part 7: Extent of stria;
——Part 8: Bubble;
——Part 9: Coefficient of optical absorption;
——Part 10: X-rays stability;
——Part 11: Precise test method for refractive index in the visible wave band;
——Part 12: Spectral internal transmittance;
——Part 13: Coefficient of thermal conductivity;
——Part 14: Resistance to acid;
——Part 15: Resistance to humidity;
——Part 16: Linear thermal expansion coefficient, transformation temperature and yield point temperature;
——Part 17: Autocollimation test method for refractive index in the ultraviolet and infrared wave band;
——Part 18: Knoop hardness;
——Part 19: Abration factor;
——Part 20: Density;
——Part 21: Resistance to attack by aqueous alkaline solutions;
——Part 22: Resistance to attack by aqueous alkaline phosphate-containing;
——Part 23: Resistance to climatic.
This is Part 23 of GB/T 7962.
This part is developed in accordance with the rules given in GB/T 1.1-2009.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. The issuing body of this document shall not be held responsible for identifying any or all such patent rights.
This part was proposed by China Machinery Industry Federation.
This part is under the jurisdiction of the National Technical Committee on Optics and Photonics of Standardization Administration of China (SAC/TC 103).
Drafting organizations of this part: CDGM GLASS Co., Ltd., China Ordnance Industrial Standardization Research Institute and Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences.
Chief drafters of this part: Wang Hong, Zhou Huimin, Zhou Siyu, Yun Shidong, Ma Botao, Li Weina and Wang Congjuan.
Test method of colourless optical glass - Part 23: Resistance to climatic
1 Scope
This part of GB/T 7962 specifies the principle, environmental conditions, test steps, data processing and classification for the resistance to climatic of colourless optical glass.
This part is applicable to colourless optical glass, and may serve as a reference for other types of glass.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 678 Chemical reagent - Ethanol
GB/T 903 Colourless optical glass
GB/T 1185-2006 Surface imperfections of optical elements
GB/T 6682-2008 Water for analytical laboratory use - Specification and test methods
GB/T 12591 Chemical reagent - Diethyl ether
3 Principle
Erosion caused by atmosphere brings about metamorphic layers such as "white spot" or "blushing" on the surface of the colourless optical glass. The degree of erosion on the glass surface is determined by measuring the turbidity difference of the testing sample before and after erosion using a turbidimeter with integrating sphere. See Figure 1 for the schematic diagram for optical glass turbidity measuring device.
Keys:
1——light source;
2——collimator;
3——testing sample;
4——integrating sphere;
5——photoelectric detector;
6——light trap;
7——standard white plate.
Figure 1 Schematic diagram for optical glass turbidity measuring device
4 Environmental conditions
Unless otherwise specified, tests shall be carried out under the following environmental conditions:
a) temperature: 15~35℃;
b) relative humidity: 20%~80%;
c) atmospheric pressure: atmospheric pressure on the test site.
5 Reagents
5.1 General
Unless otherwise specified, chemical reagents shall be used during test.
5.2 Water
Grade II water specified in GB/T 6682-2008.
5.3 Ethanol (C2H5OH)
Ethanol identified as chemically pure and of above purity specified in GB/T 678.
5.4 Diethyl ether (C4H10O)
Diethyl ether identified as chemically pure and of above purity specified in GB/T 12591.
Foreword i
1 Scope
2 Normative references
3 Principle
4 Environmental conditions
5 Reagents
6 Apparatus
7 Preparation of sample under test
8 Test steps
9 Data processing and judgment
10 Test report
