Laser irradiation device, patterning method and method of fabricating organic light emitting display (OLED) using the patterning method
View Patent ↗In a laser irradiation device, a patterning method and a method of fabricating an Organic Light Emitting Display (OLED) using the same. The laser irradiation device includes a light source, a mask, a projection lens, and a Fresnel lens formed at a predetermined portion of the mask to change an optical path. When an organic layer pattern is formed using the laser irradiation device, laser radiation is irradiated onto a region of an organic layer, which is to be cut, and the laser radiation is appropriately irradiated onto a region of the organic layer, which is to be separated from a donor substrate. The laser radiation irradiated onto an edge of the organic layer pattern has a laser energy density greater than that of the laser radiation irradiated onto other portions of the organic layer pattern. As a result, it is possible to form a uniform organic layer pattern and reduce damage of the organic layer.
1. A laser irradiation device to irradiate a substrate, the device comprising:
a light source;
a mask arranged under the light source; and
a projection lens arranged under the mask;
wherein the mask includes a first region including a Fresnel lens arranged on a predetermined portion thereof to change an optical path of light generated by the light source and a second region including no Fresnel lens to allow the light generated by the light source to pass therethrough without changing an optical path of the light, the first and second regions lying in the same plane and the first region enclosing the second region; and
wherein the light whose path has been changed by the Fresnel lens is focused onto an edge of a portion of the substrate irradiated by the irradiation device to produce an energy density greater than the energy density of other portions of the irradiated substrate.
2. The laser irradiation device according to claim 1 , wherein the Fresnel lens is arranged on at least one of an upper surface and a lower surface of the mask.
3. The laser irradiation device according to claim 1 , wherein the Fresnel lens is arranged on the mask by machining a predetermined portion of the mask to have a Fresnel lens shape.
4. The laser irradiation device according to claim 1 , wherein the mask comprises a transparent material.
5. The laser irradiation device according to claim 4 , wherein the transparent material comprises either glass or transparent plastic.
6. The laser irradiation device of claim 1 , wherein light focused on the edge of the portion of the substrate irradiated by the Fresnel lens overlaps light irradiating the edge of the portion of the substrate irradiated by the second region of the mask having no Fresnel lens.