Abstract: A steering device includes: a steering shaft structured to receive rotational force; a rack bar in engagement with the steering shaft; and a rack housing that is made of a metal and contains the rack bar such that the rack bar is movable. The rack housing includes a tubular section extending in a movable direction of the rack bar, and includes a first inclination section disposed in an axial end of the tubular section and inclined to go away from the rack bar outwardly in a radial direction with respect to the rack bar. The tubular section is structured to contact with the rack bar in response to warping of the rack bar due to input from outside. The first inclination section is structured to contact with the rack bar later than the tubular section in response to warping of the rack bar due to input from outside.

Abstract: An electric power steering device including a first bolt boss of a second housing provided on a first housing side relative to a worm-wheel accommodating portion of the second housing, and has a first female thread portion open on the first housing side and located within a plane area defined by connecting a second pinion shaft, a first bracket hole, and a second bracket hole; and a first bolt boss of the first housing provided to the first housing to be opposed to the first bolt boss of the second housing, and has a first bolt hole located within the plane area defined by connecting the second pinion shaft, the first bracket hole, and the second bracket hole and being formed through the first housing to be continuous with the first female thread portion of the first bolt boss of the second housing.

Abstract: This invention discloses a hydrogenated oil flavor-imparting agent comprising vanillin and/or ethyl vanillin, and hydrogenated-oil-flavored oil and fat formed by use of the agent.

Abstract: An observation optical apparatus includes an objective unit; the first path splitting member placed on the optical axis of the objective unit for splitting an optical path from the objective unit into two; the first optical system situated on one of two optical paths split by the first path splitting member, for forming an image at least twice; the first observation device-located at the imaging position of the first optical system; the second optical system situated on the other of the two optical paths, having a higher total magnification and a larger numerical aperture than the first optical system; the second observation device located at the imaging position of the second optical system; and a stop for low magnification, placed at the pupil position of the first optical system, for reducing the numerical aperture.

Abstract: The invention provides an immersion microscope objective which has a magnification of about 100.times. and a high numerical aperture of the order of 1.65, and is particularly excellent in axial optical properties. The first lens unit G.sub.1 consists of a cemented doublet of a plano-convex lens and a meniscus lens concave on the object side and a positive meniscus lens concave on the object side, three in all; the second lens unit G.sub.2 consists of a cemented triplet of double-convex, double-concave and double-convex lenses; the third lens unit G.sub.3 consists of a cemented doublet of double-convex and double-concave lenses; the fourth lens unit G.sub.4 consists of a cemented doublet of a double-convex lens and a negative meniscus lens concave on the object side; the fifth lens unit G.sub.5 consists of a cemented doublet of double-convex and double-concave lenses; and the sixth lens unit G.sub.6 consists of a cemented doublet of double-concave and double-convex lenses.

Abstract: An immersion microscope objective which has a magnification of about 60, an NA of 1.4, and a reduced number of constituent lens elements and yet which is satisfactorily corrected for spherical and axial chromatic aberrations and is also superior in the flatness of the image field.

Abstract: An apochromat-class immersion microscope objective having a magnification of about 40, a NA of about 1.0, and a satisfactorily flattened image field. The microscope objective includes a first lens unit G1 of positive refractive power which has a cemented lens composed of a plano-convex lens and a meniscus lens having a strong concave surface directed toward the object side, a second lens unit G2 having a cemented lens composed of three lens elements, that is, negative, positive and negative lenses, a third lens unit G3 having a cemented lens, a fourth lens unit G4 including a cemented meniscus lens having a strong concave surface directed toward the image side, and a fifth lens unit G5 including a cemented meniscus lens composed of a negative lens and a positive lens and having a strong concave surface directed toward the object side.

Abstract: An optical system for microscopes includes an objective lens for collimating beams of light emanating from an object and an imaging lens for forming parallel beams emerging from the objective lens into an image of the object at a predetermined position, and satisfies the equation:0.5 f<W<1.1 fwhere W is the variable amount of spacing from the contact surface of the objective lens to the surface of incidence of the imaging lens and f is the focal length of the imaging lens. Thus, the optical system for microscopes allows a large variable amount to be secured while holding a good imaging condition and is unsurpassed in extensity of the system to be able to accommodate various modes of observation.

Abstract: The invention relates to an objective-with-a-corrector-ring for microscopes that is of about 40 magnifications and has an NA of 0.93 with well-corrected aberrations over an ultra-wide field range, and is less likely to degrade in performance due to a thickness variation of the cover glass. This objective comprises a first lens group G1 that includes a positive meniscus lens concave on the object side and has positive refracting power as a whole, a second lens group G2 that is movable along the optical axis and has small refracting power, a third lens group G3 that is of positive refracting power and converts an exit luminous flux leaving the object and passing through said first and second lens groups to a converging flux, and a fourth lens group G4 that includes two lens surfaces opposite on the concave surfaces to each other through an air separation. The second lens group is movable relative to the first and third lens groups depending on a thickness change of the cover glass.

Abstract: The invention provides an ultra-wide field eyepiece for microscopes, in which such off-axial aberrations as the curvature of field, astigmatism and coma are well-enough corrected at a field number as large, as 26.5, and in which the flatness of the image surface is degraded even when the entrance pupil position varies, and which comprises, in order from the entrance side, a first lens unit G1 of negative refracting power, a second lens unit G2 of positive refracting power, a third lens unit G3 of negative refracting power, a fourth lens unit G4 of positive refracting power and a fifth lens unit G5 of positive refracting power with the surface having a stronger curvature facing the entrance side, said third to fifth lens units being located in the rear of an intermediate image plane.

Abstract: An eyepiece lens system comprising, in the order from the side of incidence of rays, a first lens unit having positive or negative refractive power as a whole and a second lens unit having positive refractive power as a whole, said eyepiece lens system having little aberrations, image surface flatness excellent to the marginal portions of visual field, a high eye point and a wide visual field.

Abstract: A high magnification objective lens system comprising, in the order from the object side, a first positive lens unit which comprises a positive meniscus lens component having a concave surface on the object side and a plurality of positive cemented lens components, and has a function to converge a light bundle coming from an object, a second negative lens unit which comprises a negative lens component having a concave surface on the object side, a third lens unit which comprises a positive cemented lens component and has a positive refractive power, and a fourth lens unit which has a negative refractive power. This objective lens system has magnification on the order of 250.times. and a long working distance, and is of the apochromatic grade.

Abstract: The improved process for preparing para-hydroxybenzoic acid comprises reacting potassium phenol with carbon dioxide in an inert reaction medium or without using a reaction medium in the presence of at least one compound selected from the group consisting of the compounds represented by the following general formula I or II: ##STR1## at a reaction temperature of 230.degree.-450.degree. C. and at a carbon dioxide pressure ranging from atmospheric pressure to 6 kg/cm.sup.2 (G). The process may comprise two stages and the first-stage reaction described above is followed by the second stage in which the reaction is further continued with the pressure of carbon dioxide in the system being reduced and/or the reaction temperature being elevated within the range specified above.Also, phenol may be used as the starting material instead of potassium phenolate.

Abstract: Para-hydroxybenzoic acid is prepared by reacting an alkali metal salt of phenol except the lithium and sodium salts with carbon dioxide in the presence of at least one compound selected from compounds of the following formulae (I) and (II): ##STR1## In formulae (I) and (II), M is an alkali metal except lithium and sodium; R is any substituent except an aliphatic hydroxy group having up to 4 carbon atoms, an aliphatic mercapto group having up to 4 carbon atoms, a substituent having at least one of them as its structural unit, and a hydrogen atom; R' is any substituent except an aliphatic hydroxy group having up to 4 carbon atoms, an aliphatic mercapto group having up to 4 carbon atoms, and a substituent having at least one of them as its structural unit; in formula (I) n is an integer of 1 to 5, and R groups may be the same or different when n is more than one; in formula (II) m is an integer of 1 to 5 and l is an integer of 0 to 4, and M alkali metals may be the same or different when m is one or more, and R'

Abstract: An objective lens for microscopes comprises a first lens unit, a second lens unit which is movable along an optical axis, and a third lens unit. The second lens unit includes elements of a compound lens component cemented to each other to dispose an optical modulator consisting of an annular phase diaphragm on their cemented surface. The objective lens is capable of canceling variation of aberration caused by a thickness of a cover glass and bringing about a modulated image with favorable contrast.

Abstract: An optical system for microscopes includes an objective lens for collimating beams of light emanating from an object and an imaging lens for forming parallel beams emerging from the objective lens into an image of the object at a predetermined position, and satisfies the equation:0.5 f<W<1.1 fwhere W is the variable amount of spacing from the contact surface of the objective lens to the surface of incidence of the imaging lens and f is the focal length of the imaging lens. Thus, the optical system for microscopes allows a large variable amount to be secured while holding a good imaging condition and is unsurpassed in extensity of the system to be able to accommodate various modes of observation.