| 摘要 |
PURPOSE:To enable direct printing on a paper while omitting a photosensitive drum, by pertinently selecting an ink, applying the ink on the surface of the paper and irradiating and exciting the ink with light to cause color forming or a color change. CONSTITUTION:A laser diode 1 of a wavelength lambda1 is used as a light source, and a thin-film lens comprising an arrayed electrode type surface acousting wave transducer 2-1, a lattice form condenser lens 2-2 and an optical waveguide 2-3 as primary components is used as an optical duct 2. A lens 3 having a focal length reducing function is intermediately provided between the condenser lens 2-2 and a photosensitive paper 7. When an elliptic lens, into which a laser beam with a scanning width l is led by the optical duct 2, is provided with a non-spherical F2 surface and is rotated or moved with an F1 point as a reference, l' is swung in the axial direction of a photosensitive paper turning-back roll by an amount corresponding to the rotating or moving distance of the elliptic lens, whereby the scanning width of the laser beam is enlarged. Monochroic printing can be performed by using a single light source, while multicolor printing can be performed by using a plurality of light sources differing in wavelength of light and three kinds of dyes for red, green and blue colors. |
