Traditional Culture Encyclopedia - Photography and portraiture - What is the actual focus noun explanation?

What is the actual focus noun explanation?

Focus is an important factor in X-ray photography. The so-called focus is the intersection of extension lines opposite to the main X-ray irradiation direction. The ideal focus is a point, which actually has a certain area. Focusing can be divided into actual focusing and effective focusing from different angles. ?

1. The actual focus is the region where the electrons emitted by the cathode lamp line hit the anode target at high speed. The thinner the electron beam, the smaller the area hitting the anode target surface and the clearer the image. ?

2. Effective focus The effective focus is the projection of the actual focus in the X-ray irradiation direction. Because the anode target surface is an inclined plane with a certain angle, in the direction of X-ray photography, it is the sine value of the actual focus that affects the imaging. Generally, the values of1.0,2.0 marked by X-ray tubes are the nominal values of their effective focus.

As a science, medical imaging belongs to biological imaging, including image diagnosis, radiology, endoscope, medical thermal imaging technology, medical photography and microscope. In addition, although technologies including EEG and brain magnetic resonance imaging focus on measurement and recording, and there is no image display, the generated data can be regarded as another form of medical images because of its positioning characteristics (that is, it contains location information).

In clinical application, it is also called medical imaging, or imaging medicine. Some hospitals will set up imaging medical centers, imaging medical departments or imaging medical departments, and be equipped with relevant instruments and equipment. There are specialized practical nurse, radiologists and doctors who are responsible for the operation of instruments and equipment, image interpretation and diagnosis (doctors are responsible in Taiwan Province Province), which is different from radiotherapy in radiology.