就在中心快门被引入照相机制造业的同时，人们还发明了一种反射镜式快门，又叫“缝隙式”快门。俗称“翻斗”快门，盖因其快门的弧形结构与上下运动的方式。现在能见到最早的文献报导是1884年美国人卡尔宾·莱·史密斯提出的专利。它是利用反射镜上的缝隙与弧形遮挡板的缝隙对 In the center of the shutter was introduced into the camera manufacturing industry, people also invented a mirror shutter, also known as “slit” shutter. Commonly known as “dumping” shutter, cover because of its arc structure and up and down movement of the way. The earliest reports that we can now see are the patents made by the American Calbin Leigh Smith in 1884. It is the use of the gap on the mirror and the arcuate shield aperture pairs