Abstract: An optical recording medium tilt compensation device having a tilt compensation unit is disclosed that is able to compensate for a tilt error in servo control when recording or reproducing data in an optical recording medium.

Abstract: A wide-angle lens is disclosed that includes a front lens group and a rear lens group that are arranged in order from an object side to an image side with an aperture being arranged between the front lens group and the rear lens group. The front lens group includes at least two lenses arranged toward the object side that have positive powers, and at least one lens arranged toward the image side that has a negative positive power. One of the lenses of the front lens group arranged second in order from the object side has a lens face that is arranged into an aspheric surface. The front lens group, the aperture, and the rear lens group make up an image forming system having an angle of view greater than 180 degrees.

Abstract: A diffraction grating with periodically arranged protrusions and grooves at a relatively narrow pitch and improved diffraction efficiency is disclosed. The protrusions of the grating are made of a material whose index of refraction is greater than that of the grooves, and the ratio of the width D of the protrusion to the pitch ? of the protrusion is set equal to or less than 0.4 (D/??0.4).

Abstract: An image projecting apparatus enables the formation of a projected image faithful to original image information by reducing degradation in the projected image due to decrease in imaging performance of a projection optical system. Image information is processed by an image processing device, which includes a first and a second image processor. A light modulating device modulates a flux of light emitted by an illumination optical system based on the processed image information. The modulated flux of light is projected on a screen by a projection optical system. If the image information processed by the first image processor in a pixel region is not within a representable modulation range of the light modulating device, the image information is processed by the second image processor.

Abstract: An information recording apparatus comprises a plurality of fine particles forming an array on a plane in close proximity of each other, each of the plural particles including a ferromagnetic metal, a light-emitting device for exciting a near-field light, and a photo-electric conversion element for detecting a near-field light traveled along the fine particles.

Abstract: A diffraction grating with periodically arranged protrusions and grooves at a relatively narrow pitch and improved diffraction efficiency is disclosed. The protrusions of the grating are made of a material whose index of refraction is greater than that of the grooves, and the ratio of the width D of the protrusion to the pitch ? of the protrusion is set equal to or less than 0.4 (D/??0.4).

Abstract: A diffraction grating with periodically arranged protrusions and grooves at a relatively narrow pitch and improved diffraction efficiency is disclosed. The protrusions of the grating are made of a material whose index of refraction is greater than that of the grooves, and the ratio of the width D of the protrusion to the pitch ? of the protrusion is set equal to or less than 0.4 (D/??0.4).

Abstract: An optical recording medium tilt compensation device having a tilt compensation unit is disclosed that is able to compensate for a tilt error in servo control when recording or reproducing data in an optical recording medium.

Abstract: A diffraction grating with periodically arranged protrusions and grooves at a relatively narrow pitch and improved diffraction efficiency is disclosed. The protrusions of the grating are made of a material whose index of refraction is greater than that of the grooves, and the ratio of the width D of the protrusion to the pitch ? of the protrusion is set equal to or less than 0.4 (D/??0.4).

Abstract: An optical recording medium tilt compensating device is provided that includes: an objective lens that concentrates light onto a recording surface of an optical recording medium, the light being emitted from a light source; an optical recording medium tilt offset detecting unit that detects a direct current component from a change with time in an optical recording medium tilt caused when the optical recording medium is rotated; and a tilt actuator that controls a tilt of the objective lens by adjusting a relative tilt between the objective lens and the optical recording medium based on the direct current component detected by the optical recording medium tilt offset detecting unit, the relative tilt being obtained from an optical recording medium tilt sensor of an optical pickup that detects the tilt of the optical recording medium.

Abstract: A tilt compensation apparatus and method minimizes a coma aberration generated due to a tilt of an optical disc by canceling a tilt offset amount of a tilt sensor. An objective lens converges a light emitted by a light source mounted on an optical pickup and irradiating the light onto a recording surface of the optical disc. An objective lens tilt actuator controls tilt of the objective lens. An objective lens tilt sensor detects an amount of tilt of the objective lens. An optical disc tilt sensor detects an amount of tilt of the optical disc. An operator computes an amount of relative tilt between the objective lens and the optical disc in accordance with the amount of tilt detected by the objective lens tilt sensor and the amount of tilt detected by the optical disc tilt sensor. A memory part stores an amount of offset of tilt generated in each of the tilt sensors.

Abstract: A diffraction grating with periodically arranged protrusions and grooves at a relatively narrow pitch and improved diffraction efficiency is disclosed. The protrusions of the grating are made of a material whose index of refraction is greater than that of the grooves, and the ratio of the width D of the protrusion to the pitch &Lgr; of the protrusion is set equal to or less than 0.4 (D/&Lgr;≦0.4).

Abstract: The invention provides a process comprising treating a lanolin fatty acid with boric acid to convert hydroxy fatty acids therein to boric acid esters, subjecting the reaction mixture to vacuum distillation to fractionate the boric acid esters of hydroxy fatty acids from non-hydroxy fatty acids, hydrolyzing the boric acid esters, and subjecting the hydrolysate to vacuum distillation to provide .alpha.-hydroxy fatty acids and .omega.-hydroxy fatty acids, the resultant respective lanolin fatty acids and esters, and cosmetic products and drug products for external use containing them.According to the invention, pale-colored, substantially odor-free lanolin fatty acids can be obtained easily and with high efficiency and these compounds can be effectively utilized in the pharmaceutical and cosmetic field.