Abstract: A light scatter detector assembly for an analytical instrument, such as a laser flow cytometer or clinical hematology instrument having at least two angles of scatter. A high numerical aperture lens system is used, preferably a system using only two lenses to collect light after interacting with suspended particles passing through a flow cell into a collimated beam. A dark stop having apertures in different locations is interposed in the collimated beam light detected to produce therefrom two optical beams, respectively corresponding to the two scatter signals, e.g., high angle scatter and low angle scatter. The apertures are preferably radial sectors. The two scatter beams are passed to a beam separating element and through a collimating lens onto respective photodetectors. The beam separating element may be a split mirror having two mirrors mounted at an angle to each other, e.g., less than 15.degree., preferably 51/2.degree., to direct the beams in different directions to the two photodetectors.

Abstract: An optical illuminator assembly for an analytical instrument, such as a clinical hematology or a flow cytometer instrument, including a laser diode having a diverging laser beam output, a collimating lens to collimate the diverging laser beam, a spatial filter operating on the collimated laser beam to spatially filter the beam, and a focussing lens to focus the spatially filtered beam into a flow cell containing particles suspended in a moving stream. A beam shaping aperture is preferably inserted between the spatial filter and the focussing lens to shape the laser beam. The spatial filter preferably includes an objective lens, a collimating lens, and a filter aperture interposed between the objective and imaging lenses. The filter aperture is preferably rectangular, having a height to width ratio in the range of 1:2 to 1:3 such that each dimension is on the order of tens of micrometers.

Abstract: An accelerometer comprises a base and cover together defining a chamber which receives an inertial mass. The diaphragm carries the inertial mass and is bolted between the base and the cover. The inertial mass and the base have facing incorrugated surfaces with offset teeth in each of the corrugated surfaces. An optical fiber is clamped between the teeth and extends between the corrugated surfaces. The intensity of light passing through the fiber changes with movement of the inertial mass with respect to the base. The inertial mass moves through the resiliency of the diaphragm, when the base is subjected to accelerations, such as those caused by vibrations. A reference optical fiber may also extend through the chamber above the inertial mass. The same light is supplied to both fibers and the intensity of light from both fibers is subtracted to leave the variation in intensity due to bending of the sensing optical fiber.

Abstract: An accelerometer comprises a base and cover together defining a chamber which receives an inertial mass. A diaphragm carries the inertial mass and is bolted between the base and the cover. The inertial mass and the base have facing corrugated surfaces with offset teeth in each of the corrugated surfaces. An optical fiber is clamped between the teeth and extends between the corrugated surfaces. The intensity of light passing through the fiber changes with movement of the inertial mass with respect to the base. The inertial mass moves through the resiliency of the diaphragm, when the base is subjected to accelerations, such as those caused by vibrations. A reference optical fiber may also extend through the chamber above the inertial mass. The same light is supplied to both fibers and the intensity of light from both fibers is subtracted to leave the variation in intensity due to bending of the sensing optical fiber.