Abstract：Under 980 nm excitation, we obtained five intense up-conversion luminescence bands in Er3+-Yb3+-Tm3+co-doped CdF2:PbF2-based glass as follows: infrared(800 nm), red(645 nm), green (545 nm and 525 nm), blue(480 nm ) and violet(407 nm) up-conversion luminescence. With the addition of Tm3+, the intensity of 480 nm blue luminescence increased notably compared with that of co-doped Yb3+-Er3+ sample，which attributed to Tm3+ special energy level structure; logI-logP plot of the luminescence intensity versus pump power shows that 480 nm luminescence emission is a two-photon excitation process induced by the cooperative up-conversion between two Yb3+ ions and the slope of logI-logP plot decreases gradually with increasing pump power and shows a tendency to bend down. The up-conversion mechanism is analｙｚed in detail ｕnder 980 nm semicondｕctor laser eｘcitation;the dependence of 480 nm up-conversion lｕminescence intensitｙ on the pｕmp power ｕnder the steadｙ states is discｕssed bｙ ｕsinｇ rate eｑｕation and the resｕlts aｇree well with the eｘperiments.
