1 Scope
This part of GB/T 7962 specifies the test methods, test steps and data processing for the refractive index and dispersion coefficient of colourless optical glass.
This part is applicable to the measurement for refractive index and dispersion coefficient of colourless optical glass with V-prism method.
2 Normative references
The following documents contain provisions which, through reference in this part of GB/T 7962, constitute provisions of this part. For dated references, subsequent amendments to (excluding correction to), or revisions of, any of these publications do not apply. However, parties to agreements based on this part are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest editions apply to this part.
GB/T 903 Colourless optical glass
3 Terms and definitions
For the purposes of this part, the following terms and definitions apply.
3.1
refractive index
ratio of propagation velocity of light in vacuum to that in medium is known as "absolute refractive index" of medium, expressed by nabs; the ratio of propagation velocity of light in air to that in medium is known as "relative refractive index" of medium, abbreviated as refractive index, expressed by n
3.2
dispersion coefficient
refractive index of medium for the lights at different wavelengths is not equal, and the refractive index difference between the lights at different wavelengths is called dispersion; for colourless optical glass, (nF-nC) refers to middle dispersion, (nd-1)/(nF-nC) refers to coefficient of middle dispersion, abbreviated as dispersion coefficient, expressed by vd
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Reagents
6 Apparatus
7 Sample
8 Test steps
9 Data processing
