To be able to increase the resolution, a simple reduction system was developed. An offset film from the priting industry is normally limited in resolution. This system is based on standard reproduction  lenses and reduction of the image by x2. This is however not a straight forward task. One problem is that the standard Rodenstock lens is not optimized for UV light. Also lots of concern is put in the  focusing isues. I the image is out of focus the  resolution will be  dramaticly decreased. Also it is important to have as  flat  field of light as possible. The great advantage is that it is possible to copy a pattern very fast and the damage of the photoresist surface is reduced compared to contact copying.


The  reduction system. 1200W Ultra  high presure mercury
 light source  UV filter condensor optics and micrometer
 allignment of the reticle is important to get correct focus.


This device was made to be able to auto center  the round glass wich
could have different diameters. Also with this configuration the thicknes
s of the glass does not affect the focus.