| 摘要 |
PCT No. PCT/SE85/00336 Sec. 371 Date Jul. 10, 1986 Sec. 102(e) Date Jul. 10, 1986 PCT Filed Sep. 10, 1985 PCT Pub. No. WO86/01921 PCT Pub. Date Mar. 27, 1986.An arrangement for producing a pattern on a light-sensitive surface by means of a spot of light (16) capable of being moved over the surface. The spot of light is generated by means of a beam of light emitted by a lighting unit, which is directed at the light-sensitive surface and is caused to strike the surface intermittently in the form of flashes of light. This takes place whilst the beam of light is moved over the surface in accordance with specific instructions from a control unit. The pattern is made up of lines running not only in a selected reference direction, but also at right-angles to the selected reference direction, and also at at least one further fixed angle to the reference direction. The lighting unit contains an aperture by means of which the width of the line can be set. The aperture produces the spot of light (16) on the light-sensitive surface in the form of an isogonal polygon having at least six sides, with a first pair of sides (17, 21) lying opposite one another and essentially parallel to one another. A second pair of sides (19, 23) lie opposite one another, are essentially parallel to one another and are essentially perpendicular to the first-mentioned pair. At least a third pair of sides (18, 20, 22, 24) lie opposite one another, are parallel to one another and lie at an angle to the first-mentioned pair of sides at the aforementioned fixed angle. The beam of light moves for each flash of light over a certain distance which is not more than the length of those sides which extend in the direction of movement. |
