Traditional Culture Encyclopedia - Photography major - What conditions should a high-quality X-ray photograph have?

What conditions should a high-quality X-ray photograph have?

1, X-ray includes quality and quantity. The quality is determined by the kv of the x-ray machine. Refers to the penetration of X-rays into human body, and its quantity is determined by mAs. Refers to the sensitivity of x-rays to film. Only when kv and mas match each other can qualified X-rays be obtained.

2.200 ma machine is equipped with 100 ma file, and the chest radiograph is 0.2s (second), that is, 20 mas, 65 kv, focal length 1.5m, limbs are generally 12-20 mas, [40+ body thickness (cm)]kv, and focal length is 0.9-.

3. The cervical spine and shoulder joint have chest radiograph status and stand position; Lumbar spine, abdomen and pelvis, 60 mas, 70kv, lateral position 100mas, 80kv, focal length 0.9-1.0m;

Extended data:

X-ray imaging principle:

The basic principle of X-ray imaging, the reason why X-rays can make human tissues form images on the screen or film is based on the penetrability, fluorescence effect and photosensitive effect of X-rays. On the other hand, it is based on the difference in density and thickness between human tissues.

X-ray is actually an electromagnetic wave with extremely short wavelength and great energy. The x-ray wavelength used in medicine is about 0.00 1-0. 1 nm.

The ability of X-rays to penetrate matter is related to the energy of X-ray photons. The shorter the wavelength of X-ray, the greater the photon energy and the stronger the penetrating power.

X-ray penetration is also related to the density of matter. Substances with high density absorb more X-rays and transmit less. Low density means less absorption and more penetration.

When X-rays pass through different tissues and structures of human body, the absorption degree is different, so the amount of X-rays reaching the screen or film is also different.

In this way, images with different light and dark or black and white contrast are formed on the screen or X-ray film.

Baidu encyclopedia-the basic principle of x-ray imaging