Secondary pressing blanks of optical glass
The company has technical workshops for secondary pressing of optical glass and processing of optical elements, and it’s mainly engaged in producing, selling of secondary pressing blanks( including lens, prisms, irregular parts and so on).
The products are mainly applied to CCTV Len, automotive len, projector, DVD, zoom sightseeing, camera, astronomical telescope, microscope, stage lamp and other optical systems.
The company has advantages on material selection of optical glass, data watch, precision annealing of high homogeneity and other sides.
2. Quality advantages
（1）High quality pressing parts with nd, vd, homogeneity, stress and other properties at class 1 are required.
（2）Large size pressing parts with diameter at Φ100-Φ245, stress at class 1 are required.
（1）Process tolerances are listed in table 1. Generally processed within a specified tolerance
External diameter of molded blank（mm）
Secondary pressing blank
External diatolerance (mm)
Thickness tolerance (mm)
（2） Conversion from polishing size to pressing size
If polished curvature radius R0 is taken as the standard, pressing part’s curvature radius R should be designed according to the following principles. If R of convex surface is greater than R0, e.g. R2＞R20 in figure 1, R of concave surface is smaller than R0, e.g. R1＜R10 in figure 1, the curvature radius of concave surface of the pressing part shall be designed by sagittal weight H1＋ΔH1, while the curvature radius of convex surface of the pressing part shall be designed by sagittal weight H2-ΔH2. Table 2 gives the principles for conversion of polishing size to pressing size.
（3）Precision control range for curvature radius
Put the standard sample plate next to the manufacturing pressing part, observe the gap length between standard size and real size (edge gap, center gap) and judge (see figure 2).
External diameter Φ
Allowable gap value
Glass that meeting the special requirements of customers or of large size