| 摘要 |
A light source for a photo-reactive curing apparatus for processes such as inkjet printing is provided, and comprises a plurality of light source elements, or modules, arranged to provide a beam profile comprising irradiation zones separated by a dark zone. The light source elements are preferably UV or visible LEDs or LED arrays. This is particularly advantageous in UV curing processes where both photo-polymerization during periods of irradiation and dark polymerization during intervals between irradiation contribute to effective curing. A distributed arrangement may be provided in which the relative positions or spacing of individual light source elements, e.g. two or more of linear LED arrays, are set to provide an exposure profile with a dark interval between irradiation zones which matches the required dark reaction interval for optimal curing efficiency. Optionally, modular or adjustable light sources may be provided in which the spacing of the light source elements are adjustable, dependent on process parameters. By setting proper periods of irradiation and dark intervals the light source provides a beam profile which is better matched to the ink chemistry, so as to control the polymerization reaction to meet the desired/required process speed not only in single pass applications but also in multiple pass applications.
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