Abstract: An object is to provide a constant velocity universal joint boot that can improve resistance to fatigue failure and achieve further extension of service life even if a constant velocity universal joint swings at a large operating angle. To achieve this object, a constant velocity universal joint boot is adopted, in which a large-diameter annular portion mounted on a mating member whose outer circumferential surface is formed into a non-circular shape, and at least a part of the inner circumferential surface of the large-diameter annular portion formed into a non-circular shape, and the large-diameter annular portion, a boot bellows portion, and a small-diameter annular portion attached to a shaft are integrated, and an annular recess is provided in that part of the inner circumferential surface of the large-diameter annular portion which is adjacent to the bellows.

Abstract: An object is to provide a resin boot that can stably exert suppression effect for rubbing noise over a long period without being influenced by rotation direction. For achieving the object, a resin boot in the present invention includes a cylindrical boot bellows portion formed such that a convex portion and a concave portion alternately continue, and the boot bellows portion includes a plurality of crossed linear grooves, on a surface of a boot slope that connects a top of the convex portion and a bottom of the concave portion.

Abstract: A campaign information processing system enabling reduction of the work of application to a campaign and enhancement of the campaign effect by changing the condition of application qualification according to the purchaser and the purchase environment. A purchase history data storage section (33) stores purchase history data including electronic settlement ID data and purchased product codes. The electronic settlement ID is, for example, an electronic money number. A campaign object product code storage section (35) stores campaign object product codes. A campaign application qualification recording section (41) creates and records campaign application qualification data in respect of the electronic settlement ID data included in the purchase history data including the purchase product code matching the campaign object product code. Points are calculated according to a point rule, and application qualification is given when the points reach a predetermined value.

Abstract: A cleavage method of bisphenols capable of yielding a product containing high-purity isopropenylphenol and phenol is disclosed, including (1) a cleavage step of supplying the mixture containing bisphenols together with chroman derivatives and flavan derivatives formed as by-products in the production process of bisphenols to a cleaving vessel and carrying out a cleavage reaction in the presence of a basic or acidic catalyst at a temperature of from 150 to 260° C. under a reduced pressure condition of not higher than 300 mmHg, (2) a distillation step of supplying the cleavage step product formed in the cleavage step in a vapor state to a distillation column and distilling at a temperature of from 130 to 200° C. under a reduced pressure condition of not higher than 300 mmHg, and (3) a reflux step of condensing the distillate from the distillation step, refluxing a part thereof to the distillation step at a reflux ratio of from 0.01 to 3, and discharging out the residue from the system.

Abstract: A preparation process of phenol aralkyl resin from phenol compound and aralkyl compound by controlling the temperature of reaction mass in the range of 70 to 240.degree. C. and simultaneously controlling the temperature of vapor phase potion and vapor-liquid interface portion of manufacturing equipment so as to keep the wall surface of the vapor phase portion and vapor-liquid interface portion in a wet state. The invention can prevent scale adhesion to the interior of manufacturing equipment, remarkably reduce the number of washing and scale removing procedures on the manufacturing equipment, and enable efficient manufacture of phenol aralkyl resin. When the phenol aralkyl resin obtained is used for a molding material, molded articles having excellent heat resistance and high reliability can be provided.

Abstract: A random-block copolymer having appropriate hydrolyzability, excellent flexibility and excellent mechanical strength, a monofilament thereof, and a process for producing the copolymer. The random-block copolymer comprises from 5 to 50 mol % of a random copolymer segment containing from 20 to 80 mol % of a lactide unit (A) and from 80 to 20 mol % of a caprolactone unit (B), and from 95 to 50 mol % of a block copolymer segment containing a glycolide unit (C).

Abstract: An optical head device uses a birefringent diffraction grating polarizer configured in a reflection type. The device includes a polarizing hologram element which reflects the light from a light source to a converging lens system and diffracts the polarized light returning from a recording medium. A total reflection film is formed on a surface of a diffraction grating which is provided periodically by an ion exchange region and a dielectric film on a surface of a crystal plate having optically anisotropic characteristics. A polarizing beam splitter film formed on a surface of the polarizing hologram element has reflectivity and transmissivity having dependency on the polarization of the incident light. In another form, a polarizing hologram element includes a polarizing hologram which has diffractive efficiency having dependency on polarization of incident light and a polarizing beam splitter film which has reflectivity and transmissivity having dependency on the polarization of the incident light.

Abstract: A method for the homopolymerization or copolymerization of vinyl chloride, wherein the inner wall of the polymerizer and the like are prevented from being fouled with the resulting polymer by applying a coating fluid containing the oxidative polymerization product of a specific phenolic monomer to the surface of the inner wall of the polymerizer and the like, as well as an anti-fouling agent used for this purpose. The method of this invention can very effectively prevent the polymerizer and the like from being fouled with the resulting polymer without affecting the polymerization rate and various properties of the product. Consequently, the necessity of performing the operation for removal of the deposited polymer after completion of each polymerization cycle is eliminated, thus making it possible to achieve closed polymerization requiring no manhole opening after each polymerization cycle which is becoming increasingly popular in recent years.

Abstract: An optical head device uses a birefringent diffraction grating polarizer configured in a reflection type. The device includes a polarizing hologram element which reflects the light from a light source to a converging lens system and diffracts the polarized light returning from a recording medium. A total reflection film is formed on a surface of a diffraction grating which is provided periodically by an ion exchange region and a dielectric film on a surface of a crystal plate having optically anisotropic characteristics. A polarizing beam splitter film formed on a surface of the polarizing hologram element has reflectivity and transmissivity having dependency on the polarization of the incident light. In another form, a polarizing hologram element includes a polarizing hologram which has diffractive efficiency having dependency on polarization of incident light and a polarizing beam splitter film which has reflectivity and transmissivity having dependency on the polarization of the incident light.

Abstract: In an image forming apparatus, a mechanism for scanning the inner periphery of a hollow cylindrical drum has stationary optics including two semiconductor lasers fixed in place. The two lasers have their p-n junction planes positioned perpendicular to each other, i.e., one of them is horizontal while the other is vertical. Lights from the lasers are combined on the same axis by a polarizing beam splitter. A quarter-wave plate has its optical axis inclined .+-.45 degrees relative to the direction of polarization. The combined wave from the beam splitter is transformed by the quarter-wave plate to light having a clockwise and a counterclockwise polarization overlapping each other on the same axis. In the rotary optics, another quarter-wave plate converts the incident light to a composite wave of linear polarizations perpendicular to each other. This composite wave is incident to a splitting element as a P wave and an S wave or as ordinary rays and extraordinary rays.

Abstract: An optical head device uses a birefringent diffraction grating polarizer configured in a reflection type. The device includes a polarizing hologram element which reflects the light from a light source to a converging lens system and diffracts the polarized light returning from a recording medium. A total reflection film is formed on a surface of a diffraction grating which is provided periodically by an ion exchange region and a dielectric film on a surface of a crystal plate having optically anisotropic characteristics. A polarizing beam splitter film formed on a surface of the polarizing hologram element has reflectivity and transmissivity having dependency on the polarization of the incident light. In another form, a polarizing hologram element includes a polarizing hologram which has diffractive efficiency having dependency on polarization of incident light and a polarizing beam splitter film which has reflectivity and transmissivity having dependency on the polarization of the incident light.

Abstract: A light radiated from a light source is focused on an optical disc by a focusing lens. A light reflected from the optical disc is introduced to a signal detection system. In the signal detection system, the introduced light is diffracted by a birefringent diffraction grating element utilizing an optical crystal. The diffracted light is received by a photodetector. Consequently, focus and track errors are detected, and information stored in the optical disc is re-produced.

Abstract: A two-dimensional image sensor 12 having openings 28 through which light can pass is formed on a transparent substrate 21 and combined with a planar light source 11 and an optical element 13 which defines optical paths. The optical element 13 is formed by combining one of a diffraction grating, a microlens and a specular surface of V-shaped grooves with a collected fiber member formed from bundled optical fibers having light shielding side faces so as to allow the transfer of an image. The profiles of these components are determined so that light may be focused upon a finger contacting area on the center line between the openings 28 and photo-sensitive elements 24 of the sensor 12.

Abstract: In order to generate a Bessel beam at a location remote from an optical arrangement, the optical arrangement includes, a first beam converging element which is illuminated by a collimated beam, a second beam converging element which is illuminated by a beam which has passed through the first beam converging element. The first and second beam converging elements ere arranged in a manner to radiate a ring beam which is parallel with an optical axis. A third beam converging element is further provided which is illuminated by the ring beam. The third beam converging element is arranged to generate a non-diffractive beam at a location which is remote therefrom. Further, an improvement of a bar code reader is disclosed, which includes a laser source for producing a laser beam. A laser beam deflecting member is provided to deflect the laser beam so as to form a scan pattern comprised of two scan lines. The two scan lines are oriented at a predetermined angle with respect to one another.

Abstract: An optical head comprises a grating lens for diffracting light beam separated from the light beam path. The grating lens is composed of a plurality of regions having different focal length and diffraction direction so that the light beam is divided into a predetermined number of light beams. Therefore, a conventional beam splitter or polarizing beam splitter is replaced by a grating lens so that the optical head can be smaller and lighter, and the precision of detecting a track and focus errors is improved.

Abstract: First to third lenses are arranged in order to have a common optical axis. The first and second lenses provide a combined lens structure for shifting an object point along the common optical axis by moving one of the first and second lenses along the common optical axis, while an image point is formed in accordance with the shifted object point by the third lens. A spot diameter is kept constant at the image point by shifting the object point.

Abstract: The present invention is directed to a method for recovering 2-chloropropionic acid so that this compound can be separated in a high-purity form. According to the method, crude 2-chloropropionic acid is heat-treated in the presence of a metal compound at a temperature in the range of 130.degree.-180.degree. C. where dichloro derivatives are contained as impurities or at a temperature not exceeding 160.degree. C. where no dichloro derivatives are contained. The metal compound is then removed at 160.degree. C. or lower. Final purification is thereafter conducted to obtain 2-chloropropionic acid as a high-purity product.

Abstract: An optical head includes a reflection type grating lens for dividing specified polarized lights into a reflected light and a diffracted light, a device for detecting a RF signal from the reflected light of the grating lens, and a device for detecting focusing and tracking error signals from the diffracted light of the grating lens. The grating lens consists of a plurality of domains having different optical properties respectively, so that the reflected and diffracted lights are obtained. The optical head further includes a total reflection prism to compensate a phase difference between polarized lights orthogonal to a grating groove of the grating lens and parallel thereto, and a polarizing prism for dividing the reflected light into two polarized lights orthogonal to each other in polarization thereof. Thus, a simple, miniaturized, and inexpensive optical head is obtained.

Abstract: For use in combination with an optical source for generating a coherent beam along a main optical axis, an optical head device comprises a diffraction grating having a plurality of grating regions which are responsive to the coherent beam for directing a zeroth-order diffracted beam to a focussing lens and are responsive to an optical beaem reflected from an optical recording medium for directing sidewards diffracted beams to an optical detector assembly. An effective area of a diameter of about 5 mm is sufficient for the diffraction grating. Each sidewards diffracted beam may form an angle of 20.degree. with the main optical axis. The optical detector assembly is used in detecting focussing and tracking errors for the recording medium and can be used in reproducing optical information from the recording medium. A six-partitioned optical detector assembly is preferred when the grating regions are four in number.

Abstract: An optical storage medium comprises a thermoplastic resin substrate having a concave and convex surface grating on one surface thereof, and a metal layer covering the concave and convex surface grating. The period of the concave and convex surface grating is less than a wavelength of light so that light reflected from the concave and convex surface grating is changed from linear polarization to elliptical polarization, while there is no change in the polarization of light reflected from a recording pit in which the concave and convex surface grating has collapsed. Therefore, information can be read out of the optical storage medium in accordance with the change of light polarization.