In this paper the various methods of test and measurement for the homogeneity of the large size and high quality optical glass are studied.The kinife edge interferometer is emphatically discussed

whose advantages are simple structure

easy to assemble and to calibrate

convenient to use

easy to judge and to read

and the data can be analyzed and processed by following methods such as the vision

the photography

and the pickup camera as well as the computer

and the high sensitivity of the shadow method and the high precision of interference method can be combined

and the optical glass size tested and measured is not limited.