McPherson has introduced the improved compact Model 234/302 monochromator. Internal surfaces have an optimised low scatter finish. It is available with a series of aberration-corrected diffraction gratings, allowing users to tune performance from 30 nm to 1100 nm. The optics have wavelength optimised reflective coatings, platinum, aluminium and aluminium enhanced with magnesium fluoride are available. Grating densities range from 2400 to 300 grooves per millimetre. Every instrument ships with masterpiece grating(s) for best instrument performance and lowest scatter. Customised gratings are available for special tasks. The new Model 234/302 may also be equipped with a grating turret. This helps the user by broadening the accessible wavelength range without breaking vacuum or purge.
The McPherson 234/302 has a digital grating drive for precise wavelength selection and positioning. Micrometer-adjustable slits vary from 0.01 mm to ~3 mm in width and 2 mm to ~20 mm in height. Software is available along with LabVIEW drivers. This instruments normal incidence design optionally has multiple input or output ports. It can be used as a spectrograph with a microchannel plate intensifier or CCD detector, or as a scanning monochromator, while remaining under vacuum.
