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Xenon's Pulsed Light System provides one of the most effective methods of photo physical and photochemical consequences of light absorption by molecules producing novel chemical pathways, such as, short-lived chemical species, charge-transfer reactions, energy transfer phenomena etc. Most important among these chemical reactions are chain scissions and cross-linking which is normally associated with permanent changes in the material. For example, cross-linking results in an increase in curing/hardening.

Rapid, light intensity UV emitted by Xenon's lamps consists of the required amount of quantum energy sufficient to break organic molecular bonds and for example, generate free radicals which enhance polymerization mechanisms. Unlike ordinary photolysis by continuous UV exposure, the excited or reactive species produced by high peak power pulsed technology are in rather large concentrations.

The efficacy of the pulsed light process through photochemical means is attributed to the unique effects of the high peak power, broad band spectral output and means to regulate the temporal and spatial distribution of the flash lamps, resulting in equipment easily set to produce the required results.

Two mechanisms using pulse light are respectively photochemical and photo thermal. Both mechanisms may be present in effective DVD manufacturing. Specific mechanistic quantification and elucidation of the actual sequence of events involved in the observed benefits attributed to the application of pulsed light effects are complex. Variations in the absorbing molecule and reactions that occur between absorbing molecules excited states and adjacent molecules depends on the specificity of the system under investigation.

The total amount of light energy that will be supplied to each type of product depends upon properties of the particular material, such as absorption coefficient, and its surface coefficient of reflection. As soon as heat is deposited in the material through absorption of the light pulse, it begins to spread by thermal conduction. By UV pulses of high intensity and a pulse duration which is short with respect to the thermal conductivity time constant, the energy may be deposited at the surface within a very short time, where little or no thermal conduction takes place which results in surface hardening. For longer pulse durations, much of the heat that is produced in the surface establishes a temperature gradient in the material and leads to a flow of heat into the deeper layers of the material. The light output in the long UV wavelength range proves best to maximize cure through volume, while the short UV is excellent for surface cures.