特大相对孔径物镜常常用于微光夜视,X线工业探伤和医用电视等,观察低照度景物的仪器上。一般医用X线诊断机,由于荧光屏的亮度很低,需要在暗室进行,而且所用X线剂量较大,医生长期受X线的伤害,因而造成职业病的很多。为改变这种状况,国外普遍采用了电视技术,把X线荧光屏上的图象,通过电视系统,转换到电视屏上来显示。这样即可以 Large relative aperture objective lens is often used for low light night vision, X-ray industrial testing and medical television, observation of low-light scenery on the instrument. General medical X-ray diagnostic machine, the screen brightness is very low, need to be carried out in the darkroom, and the larger the X-ray dose, the doctor long-term X-ray damage, resulting in a lot of occupational diseases. To change this situation, foreign countries generally use television technology, the X-ray screen images, through the television system, converted to the TV screen to display. That’s it