Abstract: A borate phosphor represented by the formula a(M.sup.II.sub.1-x, M.sup.IV.sub.x/2)O.bM.sup.V.sub.2 O.sub.5.cM.sup.I.sub.2 O.(B.sub.1-y-z,M.sup.III.sub.y, M.sup.VI.sub.z/2).sub.2 O.sub.3 :dCe,eTb wherein M.sup.II is at least one divalent metal selected from the group consisting of Mg, Be, Zn, Cd, Ca, Sr and Ba; M.sup.IV is at least one tetravalent element selected from the group consisting of Si, Ti, Ge, Zr, Sn, Th and Pb; M.sup.V is at least one pentavalent element selected from the group consisting of P, V, Nb, Sb, Ta and As; M.sup.I is at least one alkali metal selected from the group consisting of Li, Na, K, Rb and Cs; M.sup.III is at least one trivalent metal selected from the group consisting of Al, Sc, Ga, Y, In, La, Lu, Gd, Bi and Tl; M.sup.VI is at least one hexavalent meteal selected from the group consisting of Mo, Te and W; and a, b, c, d, e, x, y and z are numbers satisfying the conditions of 0<a.ltoreq.2.0; 0.ltoreq.b.ltoreq.0.3; 0.ltoreq.c.ltoreq.0.3, 0<d.ltoreq.0.6, 0.ltoreq.e.ltoreq.0.

Abstract: A rear earth yellow to red emitting phosphor exhibiting the sublinear characteristics when the current density of an excitation electron beam is increased. The phosphor is represented by the general formula:(Ln.sub.1-x-y,Eu.sub.x,Ce.sub.y).sub.2 O.sub.2 Sin which Ln is at least one of yttrium, gadolinium, lanthanum and lutetium, x is a number satisfying 10.sup.-4 .ltoreq.x.ltoreq.9.times.10.sup.-2, preferably 10.sup.-2 .ltoreq.x.ltoreq.8.times.10.sup.-2, and y is a number satisfying 10.sup.-6 .ltoreq.y.ltoreq.2.times.10.sup.-3, preferably 2.times.10.sup.-6 .ltoreq.y.ltoreq.10.sup.-3. It exhibits a wide reproduced color range, and free of color drift at a high current. The phosphor is suitable for use in a multi-color cathode ray tube and a multi-color low-velocity electron excited fluorescent display device, and makes it possible to realize a high-performance electronic display unit.

Abstract: A phosphor for infrared-to-visible conversion comprising a complex rare earth fluoride as a main ingredient and zinc fluoride having a general composition expressed by one of the following formulas:(Y.sub.1-x-y Yb.sub.x A.sub.y) F.sub.3.sup.. .alpha.ZnF.sub.2(la.sub.1-x-y Yb.sub.x A.sub.y) F.sub.3.sup.. .alpha.ZnF.sub.2 and(Lu.sub.1-x-y Yb.sub.x A.sub.y) F.sub.3.sup.. .alpha.ZnF.sub.2wherein x is in the range of from 0.05 to 0.5, y is in the range of from 0.002 to 0.09 when yttrium fluoride is the host material and from 0.001 to 0.1 when lanthanum or lutetium fluoride is the host material, .alpha. is in the range of from 1.6 .times. 10.sup.-4 to 1.6 .times. 10.sup.-3 grams with respect to 1 gram of the phosphor and A is at least one member selected from Er and Ho.