Introduction to the function of collimator

At present, the major international collimator manufacturers include Toshiba, Siemens, etc. The maximum voltage of the collimator x-ray tube produced by our company is 125kv, and the single lighting time of the bulb is 30 seconds. The customer asked what the lead leaf looks like, is it completely closed or is there a certain gap? Reply to the customer Lead leaf is optional, there is a layer, the lead leaf control is mainly manual control.
Some manual collimators are also called simple beam limiter collimators. There are two types of collimators: wire-shielding plate type and wire-shielding barrel type. The shielding plate type is to additionally install a lead plate with a certain size of square or round hole in the X tube sleeve window, and the opening of the lead plate takes the X-ray center as the center of symmetry. When performing projection, an irradiation field suitable for the size of the hole can be obtained at a certain distance. Generally, an X-ray machine is equipped with multiple shields with different apertures, and the size of the irradiation field of the corresponding distance is indicated on the top for selection. The shape of the wire-shielded barrel beam limiter is a conical metal barrel, and some are lined with a thin lead sheet to increase the protective effect. During projection, it mainly relies on the blocking and absorption of X-rays by the tube wall to limit the irradiation field. Therefore, the size of the irradiation field can be determined by the length and diameter of the shielding cylinder, and the irradiation field is generally circular.
Some collimators have indicator lights with two levels of brightness during their lifetime to meet the requirements of the illumination field when the indoor brightness is relatively high. The reflector is generally made of silver-plated plastic, and the aluminum equivalent is about 0.5mm, which will not affect the X-ray imaging. There is also a clean and transparent plastic plate in front of the collimator, which is engraved with black lines or black dots to indicate the center of the ray field. Some collimators are marked with the corresponding focal length of the field size around the knob or within the range of movement of the rod. It is mainly used to preset the field before the field indicator light is on, so that it can be faster after the indicator light is on. Adjust the size of the irradiation field to extend the service life of the indicator light.

Author:Lillian