| 摘要 |
PURPOSE:To prevent the occurrence of saw-toothed steps to be formed in the peripheral side surfaces, and thus enable a smooth outer shape to be formed by the use of laser beams having a plurality of maximum values in the distribution of irradiation energy in the diametrical direction of the laser beams. CONSTITUTION:On the upper part of a resin liquid basin 10, laser irradiation means is provided which comprises a laser emitter 31, shutter 32, mirrors 33, 34, and an ftheta lens, and when the irradiation position of laser beams is changed by rotating the mirror 34, the ftheta lens 35 is used in order to correct the optical path differences for focusing the beam converging position onto the liquid surface at all times. And, the irradiation energy distribution of the laser beams 30 applied from the laser emitter 31 shows two maximum values X having the same maximum value (max) on both side of a beam center, and the laser strength is weakened from respective maximum points X toward both sides. As such laser beams 30 are applied to resin liquid 20, the region in which an optical setting layer 40 corresponds from the beam center to the maximum points X is formed to be almost uniform in thickness. Accordingly, when the optical setting layer 40 is piled up, namely, since the approximately short trapezoid optical setting layer 40 is piled up therein, the step of each layer on the side surfaces does not appear outstandingly. |
