The Clement Focuser looks completely different than other focusers because it works completely differently than other focusers. The Clement Focuser is built with three pairs of articulating arms and 18 crossed strip flexural hinges. The crossed strip flexural hinge is actually not a “hinge” in the traditional sense, but two thin spring-tempered stainless steel strips, which flex or bend. See illustration below. The stainless steel strips cross at right angles and the axis of the pivoting movement is along the line where the strips cross, which makes for high rigidity in all but the one degree of freedom about the pivoting axis along the line where the strips cross. There are great advantages to using flexural hinges for focuser movement over traditional type bearings roller or sliding bearings. Some of these advantages are: no wear, no lubrication needed, zero-stiction, immunity to grit and dirt contamination. The Clement Focuser has the ultra-smooth movement found in fine laboratory instruments and will retain the ultra-smooth movement under observing conditions, even when covered with abrasive grit!
Drawing of Crossed Strip Hinge Concept
Crossed Strip Flexural Hinge
Ultra-low profile of just one inch
Focuser movement is constrained by three pairs of articulating arms eliminating the need for a drawtube. Nothing protrudes below the focuser base! The ultra-low profile with no protrusion below means less overhang of heavy accessories and less backfocus used, allowing almost any camera to come into focus. With the SCT, there is an optimal spacing of the secondary mirror to primary mirror where optical aberrations are minimal. The one-inch profile of the Clement Focuser allows your CCD camera to focus at the optimal focal point (minimum aberrations) typically very close to the rear boss of the SCT. Also the ultra-low profile of the Clement Focuser allow digital cameras to focus with the MakNewt telescope (e.g. Intes MN66 and MN 86) It allows for the use of a flip-mirror that would be prohibited with a high profile focuser. The one-inch profile also means there will be less vignetting than other focuser types of the same aperture.
Room to Focus
Accessories rarely focus at the same place. For example: a CCD Camera typically focuses close in, whereas, a Binoviewer, Barlow, or Telecompressor focus one or more inches out from where the CCD Camera will focus. The Clement Focuser has ample travel (as much as 3 inches) to accommodate accessories like Binoviewers, Barlows, and a range of Eyepieces. The Clement Focuser has more travel than any low profile focuser.
