放射線透過寫眞의 對照度에 關한 考察 = A Study on Radio Graphic Contrast

다국어 초록 (Multilingual Abstract)

The usefulness of any radiography is measured by its impact on the human eye to the defference of the radiographic density and frequency. Successful interpretation of any radiograph relies upon subject contrast and film contrast. Relations among the each factors various made up contrast is connected complexity to directry and indirectry or in part and the great part.

About relationship among the each factors concerned to contrast, the result of methe-matical equation is expressed as follows:

····
Where, =Contrast as the defferential density
=Radiation quality factor consider to film sensitivity
=-value of film characteristic curve
=Corrective factor concerned to source size and geometrical condition.
=Differential thickness
n=Ratio of the intensity of scatter reach the film to the transmited density.
Also, the differential density varies accordance with brightness of illuminator in relation to degree of radiographic density. And the differential density apparent eye is expressed as follows:

where are ratio of outside light to the light transmitted through the radiograph.

목차 (Table of Contents)

• Ⅰ. 序論
• Ⅱ. 對照度와 畫質評価의 問題性
• Ⅲ. 對照度와 各 影響因子와의 關係
• 1. 吸收物質의 種類와 두께
• 2. 線質과 film 感度 係数
• 3. Film의 特性
• 4. 散乱線
• 5. 線源의 크기와 幾何學的 條件
• 6. 觀察器의 밝기와 겉보기 對照度
• Ⅳ. 考察
• Ⅴ. 結論