Schlieren method is also called the schlieren (schlieren) method, is a classical optical performance skills, if the high speed camera with high time determine skill with the schlieren method together, become high-speed lines shadow to the way in detonation and shock wave physics experiment, schlieren apparatus used for the flow field performance, the shock wave front and the lit circulate and check under the high pressure to the medium of micro material on the surface of the wave system status, on radiation and interface instability and high voltage spark discharge under weak shock waves, such as the growth of a schlieren method in common use of optical test technique principle?According to the light through the process is the shape of the parallel flow district is light schlieren transmission schlieren system system reflection type conical light schlieren system?Two types of optical imaging of schlieren system reason the same.The layout of the conical light schlieren system briefly, and its sensitivity can reach the parallel light maybe may double the schlieren system, but this kind of schlieren system because it is the same of light measured area, repeat course brought by looking at the image distortion.Parallel light schlieren system can be perhaps may truly reflected by change in the view area density, widely used in the experiments.Parallel light schlieren system is divided into transmission type and reflection type two kinds, transmission type of optical imaging quality is good, but for the purpose of the view request compare with big, to the processing of large diameter and the incredibly difficult schlieren lens, reflective optical imaging is light with off-axis imaging formation as two categories, coma and astigmatism, but as long as the light path adoption "Z" shaped arrangement and the instrument will laser scalpel blade surface to adjust to the system of meridional focal stereo and radial coke on the stereo, perhaps can probably cut two types of aberration, satisfactory results can be achieved.?Transmission schlieren system diagram?Reflection type schlieren system diagram Light source through the condenser converge in narrow sewn by slit qualified intrusive as bright light source.Slit in the focal plane of the collimating lens, a collimating lens parallel light illumination test disturbed zone, then through the schlieren lens will slit imaging in schlieren lens focal solid edge.