We mcasured the scattered radiation around the various kinds of flunroscopy tables with Pocketchambers or Ionizationchambers survey meter. A Phantom or a Patient's body was the some of the s.r. of which the back s.r. was the softs and strongest. To protec〓 the back s.r. we studied the effect of a aluminium plate placed under the table and coneluded that a Al plate of 1mm thickness could reduce the back s.r. to about 50%. A new type of tables, which had the iron plate and lead gummy shcets around the patient's body, was proved to be completely safe as regard to the present softy standard.
(1) The reference between tube voltage and ratio of scatter (=Scatter dose/Incident dose) was investigated about yarious angles of scatter. Putting the ratio proportional to (kV)^n, n was obtained as 3.0〜3.5,according to the difference of quality with the scatter angle. From this result, onepcan calculate the scatter dose at any point. (2) The influence of the BaSO_4 "Brei" to quantity and quality of scatter dose was surveyed. The quantity of scatter dose was very small, and the hardness was reduced, when the Brei was taken. The discussion was offered about these results.
We have succeeded in a method of the stereography by a simultaneous exposure of X-rays, to which the enlargement technique is applied. As the film is apart from the patient, we can avoid the double images on the film by X-rays from the left and right tubes with the proper size of lead diaphragm. Besides, we must take the high voltage technique of radiography in our method, to obtain a useful photo in practice, becouse our microfocus tube has little capacity of current which brings us the shortage of X-rays amount to reach the film.
Various methods aer thought about the problem of the intensification of film image. There is the fact that our sence of vision is more sensitive for coler than for black and white image. From this point of view, we examined the tone intensification with couplar. We toned the film image with three kinds of color, cyan, mazenda and yellow, and shew how the desity characteristics changed with these colors. And through the filter of the complementary color, we found to be able to make the desity characteristics better.
The clock used in th darkroom, has many difects in construction. Then, to reject these defects, I have made a trial manufacture of the clock used in developing, which is remotely controlled and self-repeating.
When we take the radiograph, it is not only unnecessary but harmful to take the irradiation field too broad compared to the area of the object. Becouse, it incrases irradiation quantity to the patient and decreases the sharpness of the photograph. Then, as I have mede a trial manufacture of the cone which has variable solid angle, I have described below the feature of it.
If we take the photoroentgenograph without the cone, there will be much more scattered X-ray compared to the case of using the cone. I studied this phenomena by taking a photograph of the image of the scattering source. Then, I have described below the feature of it.