Abstract: An optical encoder includes: a scale having a scale grating; a light source that emits light; and a light-receiving device that receives light that has passed through the scale. The optical encoder also has a shielding plate that shapes the beam shape, which is the shape of the light emitted from the light source. The shielding plate is disposed between the light source and the scale and defines the beam shape such that the shape of a long-length contour portion and the shape of a long-length side section have no correlation with each other. The long-length contour portion is a portion extending in the measurement direction at the contour of the beam shape of the light emitted to the light-receiving device via the scale, and the long-length side section is a section extending in the measurement direction at the contour of the light-receiving device.

Abstract: Described are fuel parts comprising a crystalline polyamide resin having a terminal amino group concentration>a terminal carboxyl group concentration and excellent in fuel resistance at their weld portion, which fuel parts are suited for use as various parts to be attached to fuel tanks of automobiles and the like, and a process for producing the fuel parts.

Abstract: Described are fuel parts comprising a crystalline polyamide resin having a terminal amino group concentration>a terminal carboxyl group concentration and excellent in fuel resistance at their weld portion, which fuel parts are suited for use as various parts to be attached to fuel tanks of automobiles and the like, and a process for producing the fuel parts.