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This melting method using the glass substrate prepared in phosphate of PbS, PbSe nanocrystals , the molten glass sample after heat treatment , heat treatment conditions obtained under a variety of different samples . By X- ray diffraction (XRD), X -ray fluorescence analysis (XRF), energy dispersive X- ray fluorescence analysis (EDX), high-resolution transmission electron microscopy (HRTEM), UV - visible - near infrared spectrophotometer test means to verify the PbS, PbSe nanocrystals exist , and made a detailed analysis of the test results , summed up the preparation process of the common issues and their solutions are given , for example, how to control the annealing temperature . The results showed that: ( 1 ) In order to P 2 O 5 -Na 2 CO-3-ZnO-AlF 3 · 3H 2 O-CaCO 3 -SiO 2 for the phosphate glass substrate synthesized PbS quantum dots , the size of about 60 -100nm, sizes, and the distribution of concentration ; ( 2 ) in order to P 2 O 5 -Na 2 CO 3 -AlF 3 · 3H 2 O-Al 2 O 3 phosphate glass as the base synthesized PbSe quantum dots , greater concentration and distribution, size of about 5-10nm; (3) glass samples must be melted at high temperature stress relief annealing , and strict control of the annealing temperature and the cooling rate , in order to eliminate the melting internal stress generated in the process , so as to obtain no cracks, no broken glass samples , the annealing temperature should be controlled at temperature below the glass transition around 50 ℃ ; (4) PbO, ZnS PbS introduction of a body, the content can not be too low too low, then the S2- evaporation due to high temperatures , the formation of quantum dots of a chance , but not too high , according to the results of several tests can be seen , the glass is too opaque ; ( 5 ) preparing a silicate can be added TiO 2 as a nucleating agent , but in the phosphate glass can not, because TiO 2 melting point is too high for the 1830 ℃ ~ 1850 ℃, adding that it will causing the glass \
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