We use term Ultra High Precision Goniometer for a device which is capable of rotating a sample with resolution 0.01" ( arc seconds ) or better, and accuracy of the rotation axis better than 0.1". Several variations of such goniometers, such as two axis type, heavy duty type, a unit incorporating angular encoder etc., are being manufactured. However, design concept of these devices ( a tangent bar mechanism ) is the same for all variations.
This is an older model of a ultra high precision goniometer designed for use with light samples and rotation axis in vertical orientation. Because of light design, high load cannot be applied to the axis shaft, especially perpendicularly. This goniometer can be quickly installed on any steel base table by using four magnets. The counter arm for a detector or analyzer is driven manually, its fixing is possible by a lock.
This is our general purpose goniometer which is being used mostly at synchrotron radiation facilities. The axis shaft and bearings are reinforced in order to permit higher load in both axial and radial directions without degrading the goniometer performance. The manually rotated detector arm with a linear slide is provided as a standard. It is possible to achieve higher resolution ( 0.005" / step ) by optional changing of the gear ratio.The angular encoder can be mounted as another option.
This modification of KTG-15D goniometer has provisions for mounting Heidenhain ROD800 incremental encoder. Resolution of this model is enhanced due to increased gear reduction ratio. There is no detector arm for this modification. The adaptor on the rotation table allows mounting miniature goniometers for sample positioning (Huber Diffractionstechnik GmbH). First two units of this type were supplied together with vertical translation stages and air pad tables to Advanced Photon Source ( Argonne National Lab. ) as a high resolution 4-bounce nested geometry monochromator assembly.
This is a modification of KTG-15( AP ) goniometer equipped with Phytron ZSS type 2-phase stepping motor (can be used with 4-phase driver ) and D-sub connector in order to meet the control system standards of synchrotron radiation facilities in Europe ( ESRF, DESY ). Photo shows the device with small motorized swivel stage ( KOHZU SA05-11 ) for sample tilt adjustment is mounted on the top of the rotation table.
This is a modification of KTG-15D goniometer with motorized detector arm rotation. Detector arm rotation is driven by worm and worm wheel mechanisms actuated by a stepping motor. The detector arm can also be rotated freely by hand after releasing and turning away a block with the worm and the motor. Hinge and lock allows returning the worm to its position with good reproducibility. High resolution ( 0.005"/step ) and encoder options are possible.
This scaled down and simplified version of tangent bar type goniometer is suitable for angular adjustment of various small X-ray optical elements such as mirrors etc. Because of its compactness and light weight, this goniometer can be used in various experimental arrangements. However, rotation axis accuracy and resolution cannot achieve the values of the KTG series goniometers.
This goniometer has two parallel ultra high resolution rotation axes driven independently by two tangent bar mechanisms. Distance between the axes is made as small as possible ( 90 mm ). The goniometer was manufactured for use in high precision two crystal topograph set-up.
This goniometer has two rotation tables with common rotation axis. Both tables are driven independently by tangent bar mechanisms. The device was manufactured for use as a high resolution 4-crystal asymmetric reflection monochromator.
This goniometer has primary axis with coarse and fine drive, and two detector arm axes. All these axes are motorized. Coarse motion of is driven by the gear mechanism, while fine motion by the tangent bar. Switching between coarse and fine drive mode is being done remotely by a patented electromagnetic clutch. In addition, a high precision Heidenhain rotary encoder is directly coupled to the axis. With this arrangement, angular position of the axis can be read precisely for both coarse and fine drive modes. Air pads are provided beneath the device, permitting very smooth horizontal motion over flat surfaces.
KOHZU Precision is manufacturing a wide range of high precision rotation stages with table diameters varying from the smallest 50 mm to the largest 300 mm. There are different types such as single axis, two axis and circle type goniometers. All these stages are driven by precise worm and worm wheel mechanism. In order to assure the best performance, worm wheels for all KOHZU stages are being machined by a custom-made precise gear cutting machine in our factory. For complete description of KOHZU rotations, swivels, as well as translation stages please refer to our catalogues “ Standard Precision Positioning Stages 1999-2000 ” or “ Air-Side Precision Stages and Goniometers ”. Here we give only one example of two axis rotation stage model RA20-21 which is being used for X-ray diffraction experiments most extensively.
This two axis ( -2 ) motorized rotation stage allows rotation independently of a sample with either a detector or analyzer mounted on a side arm. Resolution of both axes is enhanced mechanically by using additional worm and worm wheel mechanism. The stage can be used in either horizontal or vertical orientation of the common rotation axis.
T This is simple 4-axis circle type goniometer ( , -circle, , 2 from the top to the bottom ) assembled out of RA07-02 with additional worm gear, RA20-51 and RA20-21 ( please refer to the catalogue ). Detector mount ( see the drawing ) can be supplied together with the goniometer.
This is small sized goniometer with 3 motorized motion axes ( circle with manual Y tilting, X swivel and Y translation ) for adjustment of optical elements. The device consists of RA09-51 circle, SA07-02 swivel and XA07-15 translation stage.
One such goniometer is installed at SPring-8 X-ray undulator beamline BL-39XU. It is being used with piezoactuator driven oscillator holding diamond crystal atop the rotation stage as a phase retarder in polarization modulation set-up ( see for example M.Suzuki et al., Jpn. J. Appl. Phys. vol.37, 1998, pp.L1488-L1490 ).
This goniometer has two parallel rotation axes tilted at 45º in the plane perpendicular to the optical axis. The position of one axis with respect to another can be adjusted by manual translation stage.
For all goniometers presented in this brochure, we are supplying a wide spectrum of sample, detector and optical element holders, conversion spacers, handles for manual rotation of motor shafts etc. These are some examples of frequently used accessories.
Goniometer Head Mount. This spacer is for mounting of miniature goniometer heads ( Huber Diffraktionstechnik Gmbh ) atop the KTG-15D goniometer table.
3 Inch Film Holder. This holder is for fast fixing of the frame with a 3 inch optical element ( film, filter etc. ).
Sample Holder This is a holder for fixing the sample to the goniometer. The holder has a translation slide for manual sample position adjustment. Sample mounting or removal can be done easily with use of this holder.
Slit Holder This holder is designed for all models of KOHZU slits. It has four magnets on the bottom for easy fixing to any steel base table. There is a clamp which allows vertical positioning of the device.