Abstract: A method of analysing a sample in the form of a droplet provided on a sample-receiving surface includes providing a light source and a detector in a housing, positioning said sample-receiving surface in or on the housing, and focussing an incident beam of light to a focal point in the vicinity of the sample. Light is detected from the sample resulting from an interaction with the sample, the sample-receiving surface, or the atmosphere surrounding the sample. At least one parameter of the detected light is measured, and the sample-receiving surface is translated relative to the housing such that the focal point is at a different region of the sample, the sample-receiving surface, or the atmosphere surrounding the sample. The step of measuring one or more parameters of the detected light is repeated following the translating step.

Abstract: A method of analysing a sample in the form of a droplet provided on a sample-receiving surface includes providing a light source and a detector in a housing, positioning said sample-receiving surface in or on the housing, and focussing an incident beam of light to a focal point in the vicinity of the sample. Light is detected from the sample resulting from an interaction with the sample, the sample-receiving surface, or the atmosphere surrounding the sample. At least one parameter of the detected light is measured, and the sample-receiving surface is translated relative to the housing such that the focal point is at a different region of the sample, the sample-receiving surface, or the atmosphere surrounding the sample. The step of measuring one or more parameters of the detected light is repeated following the translating step.

Abstract: An apparatus for analyzing optical properties of a sample includes a housing to receive a light source and a detector; a sample locus defined relative to the housing and positioned such that when a light source and a detector are in predetermined positions, the sample locus is subject to illumination by the light source and the detector is positioned to receive and detect light from the sample; a cover on the housing, the cover being movable in a hinged manner between an open position and a closed position; and a sample-receiving surface for receiving a free-standing sample in liquid or semi-solid form. When the cover is moved to the closed position it encloses the sample locus, with the sample-receiving surface being tilted away from horizontal during the closing movement and the sample being retained thereon by surface tension or adhesion and brought to the sample locus in an enclosed environment.

Abstract: An apparatus for analyzing optical properties of a sample includes a housing to receive a light source and a detector; a sample locus defined relative to the housing and positioned such that when a light source and a detector are in predetermined positions, the sample locus is subject to illumination by the light source and the detector is positioned to receive and detect light from the sample; a cover on the housing, the cover being movable in a hinged manner between an open position and a closed position; and a sample-receiving surface for receiving a free-standing sample in liquid or semi-solid form. When the cover is moved to the closed position it encloses the sample locus, with the sample-receiving surface being tilted away from the horizontal during the closing movement and the sample being retained thereon by surface tension or adhesion and brought to the sample locus in an enclosed environment.

Abstract: A method of determining an absorption or turbidity coefficient of a liquid involves storing a set of data describing a plurality of droplets or other discrete bodies of liquid of different shapes, sizes and absorption or turbidity coefficients. Each body is captured as a combination of a measurable transmission parameter obtained by modelling the interaction of light with a drop, and of one or more dimensional measurements selected from lengths, areas and volumes. The absorption or turbidity coefficient is indicated also. By measuring the transmission of light through a real body of liquid, and making measurements allowing the droplet to be specified, the absorption or turbidity coefficient associated with a droplet giving rise to the same behaviour in transmitting light can be identified from the data set.

Abstract: A method of determining an absorption or turbidity coefficient of a liquid involves storing a set of data describing a plurality of droplets or other discrete bodies of liquid of different shapes, sizes and absorption or turbidity coefficients. Each body is captured as a combination of a measurable transmission parameter obtained by modelling the interaction of light with a drop, and of one or more dimensional measurements selected from lengths, areas and volumes. The absorption or turbidity coefficient is indicated also. By measuring the transmission of light through a real body of liquid, and making measurements allowing the droplet to be specified, the absorption or turbidity coefficient associated with a droplet giving rise to the same behaviour in transmitting light can be identified from the data set.

Abstract: An optical instrument (10) has a drop-supporting surface for receiving a droplet (98) of liquid with a cover (16) mounted on the housing (12) which receives a light source and provides communication between the light source (114) and the inner surface of the cover. A loading aperture (24) extending through the cover permits access to the drophead when the cover is in a first rotational loading position, and the cover may be rotated to a measurement position in which the light source is positioned to illuminate the drop-supporting surface. A positioning mechanism provided between the cover an the housing engages the cover when it reaches the measurement position and thereby ensures that the light source and drop-supporting surface are maintained in fixed spaced-apart relationship.

Abstract: An optical instrument (10) has a drop-supporting surface for receiving a droplet (98) of liquid with a cover (16) mounted on the housing (12) which receives a light source and provides communication between the light source (114) and the inner surface of the cover. A loading aperture (24) extending through the cover permits access to the drophead when the cover is in a first rotational loading position, and the cover may be rotated to a measurement position in which the light source is positioned to illuminate the drop-supporting surface. A positioning mechanism provided between the cover an the housing engages the cover when it reaches the measurement position and thereby ensures that the light source and drop-supporting surface are maintained in fixed spaced-apart relationship.

Abstract: An analyzer comprising a source of electromagnetic radiation, a detector for said radiation and a drophead comprising a surface which is adapted to receive a drop of liquid to be tested, the drophead being positioned in use relative to the source and detector to illuminate a drop received thereon and to cause an interaction in the path of the electromagnetic radiation between the source and detector, characterized in that said surface of said drophead is dimensioned to constrain the drop to adopt a shape which is dominated more by surface tension forces than by gravitational forces.

Abstract: An analyser comprising a source of electromagnetic radiation, a detector for said radiation and a drophead comprising a surface which is adapted to receive a drop of liquid to be tested, the drophead being positioned in use relative to the source and detector to illuminate a drop received thereon and to cause an interaction in the path of the electromagnetic radiation between the source and detector, characterised in that said surface of said drophead is dimensioned to constrain the drop to adopt a shape which is dominated more by surface tension forces than by gravitational forces.

Abstract: A tensiographic drophead comprises a quartz body 10 having a terminal surface 18 with a peripheral drop suspension edge 20. A liquid feed bore 14 extends through the body for supplying a liquid to the terminal surface to form a drop 32 whose outer edges are suspended from the suspension edge 20. At least two light guides 26, 28 extend through the body for respectively transmitting light into and collecting light reflected internally from the drop. The light guides terminate above the plane containing the suspension edge such that the intensity of the reflected light has a significant second order reflection peak.

Abstract: A tensiographic drophead comprises a quartz body 10 having a terminal surface 18 with a peripheral drop suspension edge 20. A liquid feed bore 14 extends through the body for supplying a liquid to the terminal surface to form a drop 32 whose outer edges are suspended from the suspension edge 20. At least two light guides 26, 28 extend through the body for respectively transmitting light into and collecting light reflected internally from the drop. The light guides terminate above the plane containing the suspension edge such that the intensity of the reflected light has a significant second order reflection peak.

Abstract: An apparatus for use in characterising liquids by obtaining a fingerprint of the liquid. This allows one to measure a property of a liquid, and thereby distinguish between liquids. The apparatus comprises means for directing acoustic energy at a sample of the liquid, which is preferably in the form of a drop, and means for deriving a signal related to the interaction of the acoustic energy with the liquid sample. The drop may change in volume or shape during the measurements, to derive additional properties of the liquid. The apparatus and method of the invention are used in distinguishing and analysing a variety of liquid samples.

Abstract: An apparatus for measuring a property of a liquid comprises at least one guide for electromagnetic radiation, means for directing electromagnetic radiation into the guide, means for providing at least one drop of liquid in contact with the guide at a position where radiation from the guide can enter the drop, and means for deriving a signal which is a function of the interaction of the radiation with the liquid of the drop.

Abstract: A character belt for use in a high speed impact printer comprises an endless band having an outer surface on which equally spaced cylindrical sleeves are formed so as to surround central portions of cylindrical slugs extending across the width of the band. Each slug has a raised type character on at least one end face thereof. The band and sleeves are integrally formed in a molding operation which yields a band which is relatively flexible about an axis extending parallel to the band's axial direction and relatively rigid about a line coincident with the circumference of the band. The plastic material selected to form the belt preferably exhibits good elastic damping characteristics and high abrasion resistance along the band inner surface. A high tensile strength core material is embedded in the band for dimensional stability.

Abstract: A character belt for use in a high speed impact printer comprises an endless band having an outer surface on which equally spaced cylindrical sleeves are formed so as to surround central portions of cylindrical slugs extending across the width of the band. Each slug has a raised type character on at least one end face thereof. The band and sleeves are integrally formed in a molding operation which yields a band which is relatively flexible about an axis extending parallel to the band's axial direction and relatively rigid about a line coincident with the circumference of the band. The plastic material selected to form the belt preferably exhibits good elastic damping characteristics and high abrasion resistance along the band inner surface. A high tensile strength core material is embedded in the band for dimensional stability.