TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preparation (Claimed): Preparation of (I), comprising (a) preparing a mixture of a silicon-containing agent and one or several salts containing the elements Al, M, and any of A, B1, C1 and D1, which is present in the final phosphor, at a predetermined molar ratio in a solvent, (b) adding and mixing a precipitation agent, (c) performing a primary heat treatment on the mixture in a temperature of 900-1300 degree C under an oxidative atmosphere, and (d) performing a secondary heat treatment on the mixture in a temperature of 900-1300 degree C under a reductive atmosphere. Preferred Components: The alumosilicate-based phosphors compound is of formulae ((M1-x-y--2-eAxByC2z)Si1-z-eAl2eO3) (II), and ((M1-x-y-eAxB1y)Si1-eAl2eO3) (III).    TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The illumination unit has a light source that is a luminescent indium aluminum gallium nitride, which emits light in the range of 250-410 nm. Preferred Definitions:    A = Mn2+;    C1 = Ce3+, Pr3+, Nd3+, Tb3+, Dy3+ or Ho3+;    B1 = Eu2+; and    M = Ca.    EXAMPLE - 0.0013 mole of nonahydrated aluminum nitrate (Al(NO3)3.9H2O), 0.019 mole of tetrahydrated calcium nitrate (Ca(NO3)2.4H2O), 0.025 mole of silicon dioxide, 0.0025 mole of europium nitrate hexahydrate (Eu(NO3)3.6H2O) and 0.0025 mole of manganese nitrate tetrahydrate (Mn(NO3)2.4H2O) were dissolved in deionized water. Then, 0.25 mole of ammonium bicarbonate was dissolved in deionized water. Finally, the two aqueous solutions were simultaneously stirred into deionized water. The resulting solution was evaporated to dryness at 90 degrees C, and the resultant solid was annealed at 1000 degrees C for 4 hours in air. The resultant oxide materials were then annealed at 1000 degrees C for 4 hours in nitrogen atmosphere and 2 wt.% of hydrogen atmosphere. After the purification steps were performed with water and drying to obtain metal compound having a structure of formula ((Ca0.775 Mn2+0.1 Eu2+0.1) Si0.975O3:Al0.05).