Abstract: A method of processing a super-hard material having a Vickers hardness of no less than 2000 kg/mm2, the method comprising: (a) forming a surface of the super-hard material to have a first surface profile within a first root mean square deviation being no more than 5 ?m; (b) analyzing said surface of the super-hard material to detect a plurality of protruding regions on said surface; and (c) selectively processing over only the protruding regions on the surface of the super-hard material to form a second surface profile within a second root mean square deviation from the smooth target surface profile, said second root mean square deviation being no more than 100 nm.

Abstract: A mirror for use in high power optical applications, the mirror comprising: a support plate comprising a synthetic diamond material; and a reflective coating disposed over the support plate, wherein the reflective coating comprises a bonding layer of carbide forming material which bonds the reflective coating to the synthetic diamond material in the support plate, a reflective metal layer disposed over the bonding layer, and one or more layers of dielectric material disposed over the reflective metal layer, wherein the bonding layer and the reflective metal layer together have a total thickness in a range 50 nm to 10 ?m with the reflective metal layer having a thickness of no more than 5 ?m, and wherein the support plate and the reflective coating are configured such that the mirror has a reflectivity of at least 99% at an operational wavelength of the mirror.

Abstract: A mirror for use in high power optical applications, the mirror comprising: a support plate comprising a synthetic diamond material; and a reflective coating disposed over the support plate, wherein the reflective coating comprises a bonding layer of carbide forming material which bonds the reflective coating to the synthetic diamond material in the support plate, a reflective metal layer disposed over the bonding layer, and one or more layers of dielectric material disposed over the reflective metal layer, wherein the bonding layer and the reflective metal layer together have a total thickness in a range 50 nm to 10 ?m with the reflective metal layer having a thickness of no more than 5 and wherein the support plate and the reflective coating are configured such that the mirror has a reflectivity of at least 99% at an operational wavelength of the mirror.

Abstract: A method of processing a super-hard material having a Vickers hardness of no less than 2000 kg/mm2, the method comprising: (a) forming a surface of the super-hard material to have a first surface profile within a first root mean square deviation being no more than 5 ?m; (b) analysing said surface of the super-hard material to detect a plurality of protruding regions on said surface; and (c) selectively processing over only the protruding regions on the surface of the super-hard material to form a second surface profile within a second root mean square deviation from the smooth target surface profile, said second root mean square deviation being no more than 100 nm.

Abstract: A free-standing non-planar polycrystalline CVD synthetic diamond component which comprises a nucleation face and a growth face, the nucleation face comprising smaller grains than the growth face, the nucleation face having a surface roughness Ra no more than 50 nm, wherein the free-standing non-planar polycrystalline CVD synthetic diamond component has a longest linear dimension when projected onto a plane of no less than 5 mm and is substantially crack free over at least a central region thereof, wherein the central region is at least 70% of a total area of the free-standing non-planar polycrystalline CVD synthetic diamond component, wherein the central region has no cracks which intersect both external major faces of the free-standing non-planar polycrystalline CVD synthetic diamond component and extend greater than 2 mm in length.

Abstract: A free-standing non-planar polycrystalline CVD synthetic diamond component which comprises a nucleation face and a growth face, the nucleation face comprising smaller grains than the growth face, the nucleation face having a surface roughness Ra no more than 50 nm, wherein the free-standing non-planar polycrystalline CVD synthetic diamond component has a longest linear dimension when projected onto a plane of no less than 5 mm and is substantially crack free over at least a central region thereof, wherein the central region is at least 70% of a total area of the free-standing non-planar polycrystalline CVD synthetic diamond component, wherein the central region has no cracks which intersect both external major faces of the free-standing non-planar polycrystalline CVD synthetic diamond component and extend greater than 2 mm in length.

Abstract: A single crystal diamond element having a convex surface is disclosed, the convex surface including a spherical segment for which the maximum peak to valley deviation from a perfect spherical surface is less than about 5 ?m. Alternatively or in addition, the RMS deviation from a perfect spherical surface may be less than about 500 nm, or the RMS roughness less than about 30 nm. A single crystal diamond element with a radius of curvature less than about 20 mm is also disclosed. In one aspect a single crystal diamond element having a conical half-angle greater than about 10° is described. The invention also provides a method for forming a rotationally symmetrical surface on a single crystal diamond element, comprising rotating the element about a first axis, applying a laser beam to the element in a direction perpendicular to the first axis, and translating the laser beam in two dimensions in a plane perpendicular to the direction of the beam.

Abstract: A single crystal diamond element having a convex surface is disclosed, the convex surface including a spherical segment for which the maximum peak to valley deviation from a perfect spherical surface is less than about 5 ?m. Alternatively or in addition, the RMS deviation from a perfect spherical surface may be less than about 500 nm, or the RMS roughness less than about 30 nm. A single crystal diamond element with a radius of curvature less than about 20 mm is also disclosed. In one aspect a single crystal diamond element having a conical half-angle greater than about 10° is described. The invention also provides a method for forming a rotationally symmetrical surface on a single crystal diamond element, comprising rotating the element about a first axis, applying a laser beam to the element in a direction perpendicular to the first axis, and translating the laser beam in two dimensions in a plane perpendicular to the direction of the beam.

Abstract: A component comprises a silicon carbide substrate (10), a layer (14) of CVD diamond on a surface (12) of the substrate, and a smooth surface (14a) on the CVD diamond layer (14) which is a non-planar bearing or wear-resistant surface for the component.