Abstract: An apparatus for observing the optical appearance of a surface (2) of a sample (1) of semitransparent material, in particular the surface (2) of a human skin, the apparatus comprising a light source (11,12,13,16,17) for illuminating at least a region of interest of the surface (2) of the sample (1) from a predetermined direction, a camera (14) for observing a response to the illumination of the region of interest and an optical focus device (21,31) for determining if the camera (14) is in focus with the surface (2) of the region of interest. The invention also relates to a method for observing the optical appearance of the surface (2) of a sample (1) of semitransparent material, in particular the surface (2) of a human skin.

Abstract: Light source having a plurality of light elements (207) and a control system for controlling the light elements. The control system comprises a plurality of light element controllers (213), each connected to a respective light element (207), and arranged to obtain light element data; and a bus interface (203), which is connected to the light element controllers (213) via a light source bus (209). The bus interface (203) provides the light element controllers (213) with a general command, and the light element controllers generate light element drive signals on basis of the general command and the light element data.

Abstract: A method for splitting a dataset relating to an anatomical tree structure (12) comprises establishing a plurality of seed points (24) within the tree structure; establishing a length of a path (20) along the tree structure from each of the plurality of seed points (24) to each of a plurality of other points (14); establishing a Euclidean distance (26) from each of the plurality of seed points (24) to each of the plurality of other points (14); associating with the seed point (24) a measure representing a likelihood that the seed point is the root point in dependence on the established lengths (20) and distances (26); identifying the root point of the tree structure (12) as the seed point (24) associated with a maximum measure representing the likelihood that the respective seed point is the root point; and establishing the principal bifurcation point (64) in dependence on the root point.