Abstract: A method of inspecting an object including locating an object on a machine vision apparatus, attaching a light panel to the object to backlight a region of the object, obtaining an image of the region when backlit by the light panel and identifying a geometric property of the object from the image.

Abstract: The invention concerns a cranial drill system comprising one or more surgical drill elements for drilling into the brain. The invention also concerns a cranial drilling system comprising a surgical drill element for drilling into the skull and an element for penetrating the dura. The surgical drill element may comprise a profile that forms an opening in the skull having a narrower diameter portion and a wider diameter portion and the piercing element may be arranged to be a close fit in the narrower diameter portion of the opening. The invention also concerns a cranial drill system comprising a guiding element to be located in a hole formed through the skull and a piercing element for piercing the dura. The guiding element may have a passageway or channel therein for receiving the piercing element such that the piercing element is movable relative to the guide element to pierce the dura.

Abstract: A rotation detection kit, comprising a source for generating at least a first polarized beam emitted along a propagation axis, a receiver comprising at least a first beam intensity sensor and an analyzer. The analyser comprises a first polarizer device for location in the at least first polarized beam between the source and at least first beam intensity sensor. The first polarizer device is configured such that the receiver can measure rotation between the source and the analyzer about a first axis that is non-parallel to the propagation axis based on the at least first beam intensity sensor's output.

Abstract: An implantable fluid distribution device is described. The device includes a first inlet for receiving fluid under pressure from a remote pump. A plurality of outlets are also provided, each outlet being connectable to a fluid delivery catheter. A valve mechanism is arranged to control the passage of fluid from the first inlet to the plurality of outlets. Apparatus including the fluid distribution device, an implantable pump and a plurality of drug delivery catheters is also described. The fluid distribution device can be used to delivery drug to multiple regions in the body and the sequential delivery of drugs to different sites in the brain is disclosed.

Abstract: A method of measuring an artefact using a machine on which a measuring probe is mounted. The method has the following steps: determining the approximate position of one or more points on the surface of the artefact; using this approximate position to drive at least one of the probe and artefact to one or more desired relative positions of the probe and the surface and taking one or more surface measurements of said point on the surface of the artefact at said location, wherein there is no relative movement between the probe and the artefact whilst the one or more surface measurements are taken; and using data from the measurements to determine a position of the one or more points on the surface in which dynamic error is substantially reduced.

Abstract: A method of measuring an object with a coordinate positioning apparatus, comprises the following steps: placing the object within the working volume of the coordinate positioning apparatus; measuring the object with a workpiece contacting probe to create measurement data of the object, the measurement data being collected at multiple probe forces; for at least one location on the surface of the object, determining a function or look up table relating the measurement error data to the probe force; for said at least one location on the surface of the object, using the function or look up table to determine the measurement data corresponding to zero probe force; and outputting the measurement data corresponding to zero probe force as the measurement of the object.

Abstract: A module for mounting an optical element (e.g. a lens) in a predetermined position in an optical apparatus comprises a carrying member which holds the optical element and a receiving member, for attachment to the optical apparatus, for receiving the carrying member. The carrying member is guided into the receiving member transverse to the optical axis of the optical element by a combination of pins on the carrying member engaging with grooves in the receiving member and pins on the receiving member engaging with recessed ledges on the carrying member. Locating elements on the carrying member engage with locating elements on the receiving member to constrain the degrees of freedom of the carrying member kinematically. Magnets hold the carrying member and receiving member together.

Abstract: An optical signal transmission circuit for a probe is switched on by an optical switch-on signal comprising a burst 42 of pulses having a predetermined length. This is detected by a circuit which discriminates whether an input signal is a genuine switch-on signal or an interference burst 44, on the basis of the duration of the switch-on signal.

Abstract: An indexing mechanism is provided to enable discrete angular displacement of a first body 10 relative to a second body 12. An intermediate body 22 is provided, and is rotatable relative to both the first and second bodies 10,12. Mutually engageable detent elements on the first and intermediate 10,22, and intermediate and second 22,12 bodies, provide indexing of the first body 10 relative to the intermediate body 22 and the intermediate body relative to the second body 12 respectively. The angular separations of adjacent indexed positions provided by the first and second sets of detent elements differ such that the first body 10 is indexable relative to the second body 12 in finer indexing increments than are provided by either the first or second detent elements individually.

Abstract: A readhead for an opto-electronic encoder includes a light source, an analyser grating and a detector. The light source illuminates a scale of the opto-electronic encoder such that the light passed on by the scale forms a periodic light pattern. The analyser grating interacts with the periodic light pattern to generate a resultant fringe pattern. The resultant fringe pattern is incident upon the detector which generates a plurality of phase shifted cyclically modulating signals upon relative movement of the readhead positioned in registration with the scale. Either the periodic light pattern or the resultant fringe pattern is a linear pattern while a remaining one of the periodic light pattern and the resultant fringe pattern is an angular pattern.

Abstract: A touch probe comprises a stylus carrier which, in use, supports a workpiece-contacting stylus. The stylus carrier is urged into a kinematic rest position with respect to the housing of the probe by a spring which acts between a movable clamping shuttle and the stylus carrier. The clamping shuttle is movable within a bore and is engageable by an adjusting screw to adjust displacement of the clamping shuttle within the bore, and thus the degree of compression of the spring and the biasing force on the stylus carrier.