Optical Imaging Principles of Depth of Field(DOF)
The range of distance between the front and rear of the subject measured by the camera lens or other imager front to obtain a clear image of the image. Commonly speaking, that is, the object being photographed at the focus point plane of the scene, in the film will form a clear image, in front of the focus plane somewhere to its rear somewhere there is a range, the scene within which can form a clear image, this range is called depth of field