1.1/4λandλ test piece, quartz wedge. 2.Quintuple nosepiece with centering adjustable, the position of cross line of ocular with crosshair is always unchanged when adjusting the interpupillary distance of eyepiece tube. 3.WF10X(Φ22) super wide field Eyepiece, stress-free infinity objective 4.High-precision rotary working stage, 5.High-brightness, stress-free and aspherical swing type Abbe condenser N.A.1.30 6.Install the Quartz Crystal piece into the system to make polarization uniformity and the image color uniform in left & right optical system.