Abstract: A method and apparatus is provided for controlling the diameter of a coated optical waveguide fiber. The viscosity profile of the coating material is controlled by adjusting the temperature of a portion of the coating assembly based on a measurement of the diameter of the coated fiber. By controlling the viscosity profile of the coating material, the amount of coating applied to the fiber is controlled,, thereby determining the diameter of the coated fiber.

Abstract: An optical waveguide fiber with a core region 1 and a cladding region 2, wherein said cladding region 2 includes an outer cladding region 3 is disclosed wherein said outer cladding region 3 is a very thin (less than 1 .mu.m in thickness) layer of TiO.sub.2 --SiO.sub.2 glass which results in a substantial reduction in the number of fiber breaks resulting from the fiber drawing process and having a predetermined TiO.sub.2 concentration less than or equal to about 10 wt. %. A method for making said fiber is also disclosed.

Abstract: An optical waveguide fiber with a core region 1 and a cladding region 2, wherein the cladding region 2 includes an outer cladding region 3 is disclosed wherein the outer cladding region 3 is a very thin (less than 1 .mu.m in thickness) layer of TiO.sub.2 -SiO.sub.2 glass which results in a substantial reduction in the number of fiber breaks resulting from the fiber drawing process and having a predetermined TiO.sub.2 concentration less than or equal to about 10 wt. %. A method for making the fiber is also disclosed.

Abstract: A split recoating mold for use in recoating optical waveguide fibers with a UV-curable resin is provided wherein: (1) the mold, when closed, forms a cavity for receiving the portion of the fiber which is to be recoated, the cross-sectional size and shape of the cavity being essentially equal to the cross-sectional size and shape of the original fiber; (2) the mold includes an injection port for introducing a UV-curable resin into the cavity; and (3) the mold includes means for introducing ultraviolet light into the cavity so that resin located in regions of the cavity remote from the injection port will cure prior to resin located in regions of the cavity near the injection port.

Abstract: A method of measuring the degree of partitioning of a labeled species between free and bound states which involves the use of an insoluble porous monolith having a means for binding a portion of the labeled species within the pores thereof, which monolith is capable of substantially attenuating the signal emitted by labeled species subsequently bound within the pores thereof.

Abstract: A hand-held device for causing a blood sample to be controllably drawn into a flexible envelope or the like. The envelope is placed between a rigid and a hinged member disposed within the housing of the device, and a roller advanced along the hinged member to progressively compress the envelope. When the wheel is moved back along its path, the envelope is allowed to progressively expand thereby drawing the blood sample into the envelope.

Abstract: A pipetter for drawing fluid into capillary tubes and the like. A capillary tube is forced into an adapter coupled to one end of a vented, flexible tube. A compression wheel rides in a guideway adjacent the tube, and is rolled to continuously vary the point at which the tube is compressed in the manner of a peristaltic pump. Manual rolling of the wheel away from the capillary tube produces sufficient suction in the tube to cause liquid to be drawn into it. The pumping action is reversible in that rolling the wheel back toward the capillary tube will cause fluid to be expelled. Provision is made to prevent undesirable "compression set" as a result of long term static of the flexible tube during periods of non-use.

Abstract: A linear peristaltic pump is disclosed. The pump includes a pivotal pump arm and a flexible tube secured thereto to inhibit longitudinal tube movement. A means for applying a force to such arm, such as a spring, is provided to cause the pump arm to pivot. A stop device is disposed in the path of travel of the pump arm so that the pump arm pivotal travel may be terminated as the pump arm comes to rest against such stop device. The flexible tube is disposed adjacent a surface of the pump arm and is pivotal therewith so that the flexible tube is pinched off between the pump arm surface and the stop device as the pump comes to rest against it. A rotatable roller assembly is provided having at least one roller mounted on a rotatable roller support, the roller intermittently contacting the flexible tube as the roller support is rotated causing a quantity of liquid to be peristaltically moved within the tube.

Abstract: A recorder pen is mounted on the sample scanning stage of an electrophoretic sample analyzer. Movement of the stage scans the sample optically while, at the same time, the recorder pen produces an analog record of the optical analysis. A sample holder is mounted in the stage for detented movement in the direction orthogonal to the scanning motion of the sample stage. The sample holder can be moved to one of several detented positions so that different tracks of the samples are scanned.

Abstract: In the preparation of blood films for microscopic examination a slide spins in a centrifuge for a time which is a function of the red blood cell concentration of the blood. A drive circuit controls the time of spinning of a slide centrifuge. A variable control for the centrifuge motor includes a manual adjustment which is adjustable across a scale labeled as a function of the percent hematocrit of the blood.

Abstract: In a system which automatically analyzes laboratory slides, the adjustable objective lens is automatically focused. A beam splitter splits light from the slide into two parts. One slide image is projected to an actual image plane where it is converted into electrical signals representing the optical characteristics of the slide. The other slide image is projected to a parfocal image plane at which two light sensing devices for the focusing system are positioned. One light sensing device is in front of the parfocal image plane and the other is behind the parfocal image plane. These light sensing devices produce electrical signals representing the position of the actual image plane with respect to the desired image plane. The electric signals are differentiated and then applied to a comparator which supplies pulses to a stepping motor which moves the objective lens.