SRA Optical Stage: High-precision micrometer positioners for optic, integral rotary shutter mechanism and safety interlocks, adjustable Kb filtering from 0 to 20 µm. No-filter position allows rapid specimen quality survey and data collection from weak diffractors for which Kb intensity is negligible or readily resolved. X-Y adjustable "microbeamstop" for minimum exposed coldstream beam-path between exit collimator and beamstop (12mm). Stage replaces standard camera-shutter to permit maximum solid-angle collection from source and features helium beampath from coldstream up to generator high-vacuum window.
Beam diameter at crystal: 100 µm FW
Beam divergence: 0.2° Full width above background
Monochromaticity: 97% Ka, <1% Kb (minimum filtering)
Cell-edge resolution: 400Å at 300 mm camera length
Beam focus position: at crystal, 200mm from anode target position
Intensity: 50x collimation [with filter present]
Rotating anode X-ray generator, Cu anode, 0.07 x 0.7mm target focus cup
Specimen oscillation stage with lateral translation (oscillation axis 200mm from anode target, at 6° take-off angle)
Specimen telescope with crosshairs/graticule
Helium feed for optics (optional for 15% added flux - optic does not tarnish)
Relative intensities for the S70PX system fitted to either the MicroMax007® or FR-E®
Optical system S70PX rel. I S70PX rel. SNR MSC "Blue" optics 6x 12x Osmic VariMax HF optics 3x 6x
Notes: Intensity is flux per unit area at specimen position.
"rel SNR" is beam intensity / background scatter at equivalent angles - [How is this defined?]
Comparison with VariMaxHF configured for equivalent cell-edge resolution to S70PX
"MicroMax" and "FR-E" are registered trademarks of Rigaku corp.
VariMax is a trademark of Osmic inc.
Clearances: Oscillation axis to beamstop positioner: 32mm; Depth of shutter unit below beam axis: 86mm
Base plate: Form-factor of integral base plate is matched to specified make and model of X-ray generator. This ensures minimal optical alignment effort at installation.
Shutter unit: High-speed longlife rotary solenoid. Optical shutter position interlocks. Replaces standard camera/rotary shutter fitted to anode tower. Connection to existing X-ray generator interlocks and shutter controller is supported by the unit.
Alignment: Optical alignment upon installation is achieved by monitoring beam intensity at the specimen position (requires radiation meter) whilst adjusting optic position. Intensity max. corresponds with optimal alignment. Trim alignment (e.g. after anode assembly refit) is facilitated by fine adjustment verniers on X-Y adjusters.
Exit collimator: The system is fitted with a fixed 0.1mm exit collimator which incorporates multiple lead and platinum apertures as scatter arrestors. Optic carrier is factory pre-aligned with exit collimator prior to shipment.
Beamstop: 1.0mm diameter micro-beamstop is positioned just outside the coldstream to minimise X-ray scatter. The beamstop extension arm swivels to allow easy access to the goniometer head for specimen placement and removal.
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