Illuminating system providing collimated light for exposure of photosensitive layer - has mirrors and lens system to direct parallel light beams to selected areas of, e.g. photolacquer coating of PCB

摘要

The illumination system provides collimated light for selected illumination of photosensitive layers, esp. for mfg. p.c.b.'s. A light source is provided in a focal point of an elliptical mirror (3). A parabolic mirror reflects the light onto the photosensitive layer. A quartz lens system (5) is arranged behind the focal point of the light reflected from the elliptical mirror (3). This produces a parallel bundle of beams. A rotating 45 deg. angled mirror (6) and a parabolic reflective strip (8) are also provided. Rotation of the angled mirror (6) moves the light reflected from it in the elongate direction of the strip (8). ADVANTAGE - Simple and inexpensive to mfr., relatively compact, adjustable to different surfaces, provides uniform, simultaneous illumination and can be adjusted according to dust content suspended in air.