Abstract: In a method for scribing fragile material, a laser beam is irradiated onto a work plate of the fragile material. The work plate is heated by absorption of the irradiated laser beam and generating thermal stress by the heating. The laser beam is formed by a plurality of laser beam groups arranged along a beam scanning direction on a same line, and the plurality of laser beam groups are divided into two groups. One takes charge of initial heating and rising up temperature of the work plate, and another takes charge of temperature holding of the work plate. The laser beam intensity corresponding to each of the laser beam groups is adjusted so as to obtain optimum values. By the method, it is possible to remarkably increase scribing speed of the work plate of the fragile materials without increasing heating temperature.

Abstract: In a method for scribing fragile material, a laser beam is irradiated onto a work plate of the fragile material. The work plate is heated by absorption of the irradiated laser beam and generating thermal stress by the heating. The laser beam is formed by a plurality of laser beam groups arranged along a beam scanning direction on a same line, and the plurality of laser beam groups are divided into two groups. One takes charge of initial heating and rising up temperature of the work plate, and another takes charge of temperature holding of the work plate. The laser beam intensity corresponding to each of the laser beam groups is adjusted so as to obtain optimum values. By the method, it is possible to remarkably increase scribing speed of the work plate of the fragile materials without increasing heating temperature.

Abstract: An Er:YAG laser includes an Er:YAG crystal medium and optical pumping element and is adapted to oscillate at a wavelength of 2.94 ?m. The optical pumping element irradiates pumping light pulses onto a plurality of regions along a longitudinal direction of the Er:YAG crystal medium from its side at timings offset from each other, thereby exciting the respective regions. By exciting the spatial regions of the laser medium in a time-sharing manner, Er ions in an unexcited region of a 4I13/2 level serving as a lower level in the 2.94 ?m-wavelength laser are reduced by a non-radiation process and, therefore, it is possible to achieve the increase in power of the 2.94 ?m-wavelength laser output of the Er:YAG laser.