Classification and characteristics of different glow powders(2)

2. Calcium halophosphate phosphor

Halide calcium phosphate phosphor luminescence is activated by the activator antimony (Sb) and manganese Mn together. The activator atoms occupy the position of calcium atoms within the dot matrix. This material has a sensitization phenomenon: when the activator Sb absorbs the excitation energy, a part of the energy is released in the form of light radiation, and the other part is transferred to Mn in the so-called resonance transfer process, so that Mn produces its own radiation. 

Therefore, the total radiation depends on the properties of the two activators and varies with its ratio, and also depends on the ratio of fluorine and chlorine. If the content of Mn is increased within the Sb-activated calcium halophosphate, the orange-yellow radiation will be increased, and the blue radiation will be reduced accordingly. Using the above phenomenon, just change the content of Mn, you can get different color temperature of calcium halophosphate phosphor.

3. High-pressure mercury lamp phosphor

The spectral distribution of high-pressure mercury lamps is significantly different from that of low-pressure mercury lamps (fluorescent lamps). In order to increase the efficiency of the lamp and improve the light color, high-pressure mercury lamps are coated with phosphor in the outer glass shell of the discharge tube, which converts one of the main radiation wavelengths, 365nm ultraviolet energy, into visible light. Early high-pressure mercury lamps use manganese-activated magnesium fluorogermanate or tin-activated zinc strontium phosphate powder, etc..

Later, the use of color TV phosphor YVO4:Eu, which has a peak of 619nm, the corresponding high total glow flux of the lamp good color rendering performance. Y (PV) O4: Eu phosphor has been developed, which is more suitable for the requirements of high-pressure mercury lamps.

4. Ultraviolet light source with phosphor

It is in 253.7nm or other shorter wavelength UV excitation, can produce another longer wavelength of UV phosphor. It has many kinds. (BaSi2O3):Pb phosphor is an effective ultraviolet phosphor with a peak of 350nm, used for black light for trapping and killing pests. Calcium orthophosphate [(Ca, Zn)3(PO4)2:Tl] phosphor is an efficient powder for manufacturing health line lamps emitting at 280-350nm with a peak of 310nm. copy lamps must have spectral lines matching the absorption of the photoreceptor or photoelectric surface used, therefore, strontium pyrophosphate (Sr2P2O7:Eu) for diazo copy lamps, magnesium galliumate ( MgGa2O4:Mn) and zinc silicate (Zn2SiO4:Mn) UV phosphors.