Product Description
This is a two-axis gimbal-type mirror / lens mount marketed by Coherent Optics, Model Number 58. The mounting is quite clever – the turning axes are cylindrical magnets that also act as bearings. Two Starrett micrometer spindles actuate the motions. They bear against additional magnetic pads. I am not sure how repetitive the positioning is but there doesn’t seem to be much play at all in the bores for the magnet bearings.
The mirror mount will accept mirrors up to 2” in diameter, and using the clamping ring supplied, between 0.350” and 0.700” thick if the ring is not to be set proud of the mounting face. Clear aperture of the mount is 1.875”. Aperture is reduced by the clamping ring to 1.750”. Tilting range of both axes easily exceeds plus or minus 6 degrees.
The mounting base is 3.875” by 2.000” wide and has two counterbores for ¼ 20 cap screws 2” apart, centered on the optic axis of the mount. The optic axis is located 1.375” from the end of the mounting plate.
The mount is in very fine condition. There has been a very small slot milled in the top center of the mirror mounting cell, visible in the third photo. Both micrometer spindles are provided with extended shafts for attaching drive gearing.
Location MB 55-1
Photo set 550