High-quality steel honeycomb optical tops: The high-quality steel honeycomb optical tops that consist of a steel honeycomb core laminated with steel top and bottom skins provide high stiffness with respect to low weight. The steel honeycomb core is sandwiched between two faces of skin materials (laminated with steel bottom and ferromagnetic stainless steel top skins) and finished with side panels.

Working surface :The top skins are stretcher-leveled and pressure bonded to achieve excellent top flatness and tightly sanded with an orbital pattern to remove burrs and provide non-glare & non-reflecting finish.
Honeycomb core: Honeycomb core is made of 0.3mm thick steel, plated to prevent corrosion, closed-cell structure with basic cell size of 3.2cm² giving core density of 3*l0⁴kg/㎤,
Bonding : The bending process is critical to long term performance. The honeycomb core, skins and side walls are rigidly and permanently bonded with specially formulated high strength adhesive, which has no viscoelastic creep and hysteresis.
Sealed mounting holes : Standard mounting holes on the top are lead-screw tapped (either M6-1.0 on a 25mm grid or 1/4-20 on one inch grid) and slightly countersunk to remove ridges and burrs. Sealed mounting holes in register with open cells in the honeycomb core assures that all mounting screws can be inserted to full depth. Spills of water,solvents or hazardous chemicals can be readily cleaned up, and small objects into a hole can be retrieved.

How to select top thickness: In general, top thickness is proportional to static rigidity and dynamic natural frequency, it does not affect compliance directly. A top length to thickness ratio of 10: 1 is a safe rule for most general applications, but in case of very sensitive optical experiments at severe environments, it might be 7 : 1. Small 5Omm thick optical tops should be supported on uniform flat surfaces, not post mounts. But 1OOmm thick tops may be supported on post mounts.