This is a 1.25x relay optic used for printing on substrates from photo masks. It is corrected for 308nm wavelength which indicates fused silica or quartz optics throughout. The tube assembly is 3 inches in diameter and 21.75 inches long. The objectives have a clear aperture of 48mm. Both ends of the tube include special protective metal cover plates that may secured by button-head cap screws. The lens cells appear to be quite elaborate.
The tube assembly is supported by a baseplate 13.25 inches in length and 4 inches wide. The plate is 0.375 inches thick. It includes a pair of Melles Griot rack & pinion adjustable height pin carriers each holding a mounting ring. Fine centration is accomplished using 100 TPI thumb screws which bear against a spring loaded plunger. The optic axis height is nominally 5 inches from the bottom of the base plate. The rack & pinions have about half inch travel, and the adjustment screws within the tube yokes have approximately plus / minus 3mm in height and aximuth.
One side of the tube is marked 'substrate' and the other 'mask'. The Tamarack Scientific part number is 690.0002. We were unable to identify which camera system(s) with which these were used. The assembly is in flawless condition.
Photo set 1723