Ultrasonic biomicroscope(UBM)can clearly show the structure of the anterior segment of eyes, and can be used for the quantitative measurement, because it isn't affected by the refractive media and pupil size, and it has the advantages of non-interference, non-invasion, non-contact, real-time, and can be used for the study of the physiology and pathology, pathogenesis, diagnosis, treatment of the disease of anterior segment of eyes.