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Brilliant beams of hard x-rays, with geometrical cross-sections below 50×50 nm2, are a standard research tool for synchrotron users. With the advent of lower emittance sources, such as NSLSII, Petra III and Max IV, and planned upgraded lattices, such as APS-2, SPING8-II, ESRF II and DLS II, nanofocusing optics operating in transmission mode will become more competitive than they are currently. In general, they suffer from lower efficiency than reflective optics, however they often have easier set-up and alignment, combined with a smaller footprint. Fabrication and exploitation of ultra-short focal refractive lenses has not witnessed the same progress in the last decade as other optics, such as multilayer mirrors and multilayer Laue lenses. This paper reports on current status of high-resolution lithography for fabricating silicon lenses and on proposed designs for a new class of refractive lenses with zero aberrations and good efficiency. The new designs are created with geometrical parameters matching the spatial resolution achieved by modern lithography and silicon etch technology.

A full wave propagation of X-rays from source to sample at a storage ring beamline requires simulation of the electron beam source and optical elements in the beamline. The finite emittance source causes the appearance of partial coherence in the wave field. Consequently, the wavefront cannot be treated exactly with fully coherent wave propagation or fully incoherent ray tracing. We have used the wavefront code Synchrotron Radiation Workshop (SRW) to perform partially coherent wavefront propagation using a parallel computing cluster at the Diamond Light Source. Measured mirror profiles have been used to correct the wavefront for surface errors.

The Diamond Optics & Metrology Group and the collaborators at the STFC Central Microstructure Facility have initiated a program for the design and fabrication of in-line micro- and nano-focusing optics for synchrotron radiation beamlines. The first type of optics fabricated is a kinoform lens in silicon on the same model proposed by K. Evans- Lutterodt et al [Opt. Expr. 11 (2003) 919.]. The fabrication utilised ultra high resolution electron beam lithographic patterning of an electron sensitive SU8 polymer and deep reactive ion etching of silicon. The first test of the focusing properties was performed at the ESRF BM5 optics beamline. In this paper we present details on the design and fabrication, and discuss the test results.

A dedicated optics and metrology team has been assembled at Diamond Light Source to take responsibility for designing, procuring and testing a wide range of state-of-the-art x-ray optics, providing the Diamond beamlines with effective solutions to condition and focus synchrotron light. Advanced efforts are underway to design and construct a cleanroom laboratory to house a suite of metrology instruments. This will complement the Test beamline, used for a wide range of tasks including x-ray optics and detector developments, and proof of principle experiments. In collaboration with industrial and academic partners, these experimental facilities will be used to measure and develop the next generation of x-ray optics, and help the Diamond beamlines to achieve world leading performance. Details of the planning and early construction phase of the Metrology laboratory are presented, and preliminary examples of x-ray metrology measurements and research programmes.

The Neutron Optics Package NOP is a collection of codes for the computation of reactor spectra, neutron reflectivity of crystals, mirrors and multilayers and other quantities as cross-sections, attenuation in materials and refractive index. These calculations rely on the use of a databse of materials cross-sections and crystal structures. NOP is freely distributed as an extension of the x-ray package XOP [M. Sanchez del Rio and R.J. Dejus, SPIE proceedings 3448, 340, 1998.], from which it inherites the user interface and code structure. The NOP package can be used for estimating the reflectivity of optical elements as crystals and multilayers. The NOP output can also be used as an input for neutron instrument ray-tracing modules.

We present a Monte-Carlo algorithm for the simulation of Bragg diffraction from imperfect crystals that are used for neutron analysers and monochromators. The algorithm is used in ray-tracing simulation of neutron instruments but can also be used for x-rays. This method performs a detailed description of the particle interaction with the microscopic regions composing the crystal. It computes important quantities that cannot be calculated with standard models, as the number of multiple scattering events, and diffraction topographs. We also discuss applications of this method to the analysis of x-ray data from mosaic copper crystals.