As a part of the series of study of the mechanical properties of the human vocal folds by means of a scanning acoustic microscope (SAM), the effect of the egg albumin, which was used for fixating the specimen on a sample plate, on the acoustic image was examined.
In the first part of the study, a double blind comparison was made on the acoustic images of sample plates with and without the egg albumin. As a result, it was revealed that the egg albumin affected the acoustic image by giving unfavorable stains when the lens was focussed on the surface of the sample plate. The stains were observed even when the focus was set 20μm above the plate.
The following method was then devised to detect the stains or artifacts in the acoustic image obtained by SAM. First, two slides of acoustic images were made from two serial sections. The slides were then projected on a screen using two separate projectors with red and blue cellophane cover on the lens respectively. If there existed any artifacts in the acoustic image, they manifested themselves colored on the screen.