Adjustable Lamp Control Slit
Original Publication Date: 1980-Sep-01
Included in the Prior Art Database: 2005-Feb-13
In the projection mask alignment system, such as that used in the Perkin-Elmer Microline Models #100 and #110, a curved slit 1 is used in the condenser section, as shown in Fig. 1, to enable illumination to pass only in the region of the highly corrected image. This slit design (Fig. 1A) comprises two movable plates 2 and 3 which are trimmed to match an average Hg lamp. The plates are then epoxied in position, and any further adjustment is limited to filing open the slit.