Ytterbium doped fluorphosphate glass with long fluorescent life and preparation method of glass

The invention discloses ytterbium doped fluorphosphate glass with a long fluorescent life and a preparation method of the glass. The glass comprises the following components by mole percentage: 10-20mol% of P2O5, 25-35mol% of AlF3, 20-35mol% of CaF2, 10-15mol% of RF and 7-25mol% of R'F2, wherein a sum of the percentage of the components is 100mol%; additional 3wt% of Yb2O3 is doped according to a weight ratio; R is Li , Na or K ; and R' is Mg , Sr , Ba or Zn . The preparation method of the glass comprises the following steps that raw materials are weighed according to the formula in a glove box, mixed uniformly, and added to a graphite crucible; carbon tetrachloride is added to the crucible, and heated to 900-1100 DEG C by a high frequency furnace and kept for 45min; finally, the high frequency furnace is turned off; the temperature falls to a room temperature rapidly; and the glass is taken out and placed in a muffle furnace for annealing. The glass has better gain performance; the fluorescent life reaches as high as 2.25ms; an emission cross section is 0.8pm ; a gain coefficient is 1.8ms*pm ; and a hydroxy absorption coefficient alphaOH is less than 0.3cm .