Abstract: Dot width data of a plurality patterns each corresponding to a recording range in one scanning operation are stored in a memory in advance. Each dot width data required to correct an f-.theta. error is used to determine each dot width in one scanning operation. In accordance with the operation of an address counter, a bus switching circuit selectively reads out dot width data of a pattern different from a preceding pattern from the memory for each scanning operation, and outputs the data to a latch circuit. A programmable counter determines each dot width of image data on the basis of the dot width data from the latch circuit. A laser diode driver ON/OFF-controls a laser beam from a laser diode on the basis of the image data from the programmable counter.

Abstract: An optical scanning device for leading a laser beam emitted from a semiconductor laser diode through a collimator lens, an imaging lens, and a cylindrical lens to a plurality of reflecting surfaces of a rotatable polygon mirror, and scanning a surface to be scanned movable in a vertical scanning direction with the laser beam reflected on the reflecting surfaces of the polygon mirror and transmitted through a correcting lens. The optical centers of the semiconductor laser diode, the collimator lens, the cylindrical lens, a return mirror, and the correcting lens are located in a plane containing an axis of rotation of the polygon mirror. The semiconductor laser diode, the collimator lens, and the cylindrical lens are located over an upper surface of the polygon mirror. Accordingly, an optical system can be formed in symmetry with respect to a center axis of an optical path of a horizontal scanning light beam from the polygon mirror without interference of the semiconductor laser diode, etc.

Abstract: A laser beam emitted from the beam emitting unit is deflected for scanning by a reflector rotated by a scanner motor. The deflection scanning beam passes through a meniscus lens device provided close to the reflector, and converges the laser beam on an image-forming surface. The meniscus lens device has an incident surface, a radius of curvature of which is set smaller than that of an output surface thereof, with a convex surface thereof facing the image-forming surface. The laser beam emitting unit, the reflector, the scanner motor, and the meniscus lens device are all integrally built in a housing.

Abstract: A blood sampler of the suction-type is provided with a gasket, a lancet unit and a plunger slidable in a housing having an open front and an open rear end. A rod is connected at its front end to the lancet unit. The rod extends rearwardly over a detent integral with the inner periphery of the housing, through a central opening of the gasket and into an axial bore of the plunger. A flange, secured to the rear end of the rod is slidable within the axial bore, the gasket is slidable within the housing and behind the detent, and a protrusion formed integral with an intermediate portion of the rod is engageable with the detent. The blood sampler further has a first spring intervening between the detent and the lancet unit, and a second spring accommodated in the bore and intervening between the flange and the front end of the plunger.

Abstract: A blood separation composition for use in blood collection tubes. The composition comprises, as a gel-like material that is the main ingredient or the composition, a copolymer of sebacic acid with 2,2-dimethyl-1,3-propanediol and 1,2-propanediol. The separation composition may further comprise a thixotropic agent blended with the copolymer. The copolymer renders the blood separation composition stable and less flowable during storage, allowing it to form a stable partition barrier in each collection tube when centrifuged. The blood cells above the barrier are prevented from remaining within the serum, without any amount of harmful oily substances being released from the separation composition.

Abstract: A blood separation composition for use in blood collection tubes. The composition comprises a fatty acid amide(s) blended with a gel-like material which is the main ingredient of said composition. The amide(s) render(s) stable and less flowable the blood separation composition during storage, allowing it to form a stable partition barrier in each collection tube when centrifuged, with the blood cells above the barrier being prevented from remaining within the serum. The blood separation composition containing the fatty acid amide(s) does not release any harmful oily substance.

Abstract: A postobjective optical deflector comprising: a polygonal optical deflector (polygonal rotating mirror) having a plurality of convex reflecting surfaces each being curved surface other than a spherical surface or a portion of a cylindrical surface; and a pseudocylindrical lens disposed between the polygonal optical deflector and an objective surface, having a cylindrical surface having its power in the feed direction or a rotationally symmetric surface rotationally symmetric with respect to an axis of rotational symmetry parallel to the scanning direction, and a curved surface represented by a polynomical of even degree and having its power in the scanning direction. The combined performance of the correcting effects of the polygonal optical deflector and the pseudocylindrical lens corrects the curvature of image surfaces and f.theta. characteristics at a high accuracy.

Abstract: An optical scanning system is constructed in a compact construction by attaching a light deflecting member to one end of the output shaft of a motor internally having a space for containing parts, forming an optical path extending through the space in the output shaft of the motor between a semiconductor laser and the light deflecting member, and providing at least a collimator lens in the space for containing parts. A meniscus lens, i.e., a correcting optical system, having a concave surface of a radius of curvature in the range of 8 to 20 mm is disposed with its concave surface facing the light deflecting member so that the distance between the reflecting point on the light deflecting member and the optical center of the concave surface is in the range of 5 to 10 mm to limit the curvatures of image field with respect to the scanning direction and with respect to the feed direction of the scanning light beam are limited to a very small degree.

Abstract: A postobjective optical scanner comprising a polygonal optical deflector having a plurality of reflecting surfaces each being a curved surface varying in curvature from position to position thereon; and a correcting lens disposed between the polygonal optical deflector and the objective surface on an optical path, and having a rotationally symmetric curved surface of incidence having a cross section having the shape of an arc of a circle with its center on the axis of rotational symmetry, rotationally symmetric with respect to a plane including the axis of rotation of the polygonal optical deflector and perpendicular to the axis of rotational symmetry and having its power in both the feed direction and the scanning direction, and a surface of departure symmetrical with respect to a plane perpendicular to the scanning direction and having its power in the scanning direction.

Abstract: A postobjective optical scanner comprising a polygonal optical deflector (polygonal rotating mirror) having a plurality of convex reflecting surfaces each being a curved surface other than a spherical surface or a portion of a cylindrical surface. The deflector also utilizes a pseudocylindrical lens disposed between the polygonal optical deflector and an objective surface, having a cylindrical surface having its power in the feed direction or a rotationally symmetric surface rotationally symmetric with respect to an axis of rotational symmetry parallel to the scanning direction, and a curved surface represented by a polynominal of even degree and having its power in the scanning direction. The combined performance of the correcting effects of the polygonal optical deflector and the pseudocylindrical lens corrects the curvature of image surfaces and f.theta. characteristics at a high accuracy.

Abstract: A scanner motor controller for a laser printer or the like having a polygonal rotating mirror rotated by a scanner motor to reflect a laser beam for scanning operation. The scanner motor controller comprises a rotating speed control circuit for controlling the scanner motor for operation at a constant rotating speed on the basis of phase deviation and frequency deviation of a FG pulse signal generated by the scanner motor from a reference clock, and a rotating speed varying circuit for varying the rotating speed of the scanner motor within one turn of the polygonal rotating mirror.

Abstract: An optical scanner for a laser printer or the like, capable of forming dots on scanning lines which are apparently the same in length. When the respective scanning speeds of spots of laser beams reflected respectively by a plurality of reflecting surfaces of a polygonal rotating mirror are different from each other, correction clock pulses are inserted in a print control clock signal for each scanning line.

Abstract: A polygon mirror has a plurality of elliptically-curved convex mirror surfaces functioning as light reflection surfaces, each having substantially the same shape as the maximum curvature portion of an ellipse which has long axis b and short axis c. The convex mirror surfaces are uniformly arranged on the circumference of an inscribed circle whose center is set on the long axis b, whose radius is Rm, and which is in contact with the maximum curvature portion of the ellipse. The polygon mirror reflects an incident light beam while being rotated, and scans the incident light beam in the range of effective scanning length Lo on a preset scanning plane which is set at incident light beam travelling distance R from the center of the inscribed circle of the polygon mirror.