Abstract: An optical line sensor reads an inspection object conveyed in a sub-scanning direction by a reading line L extending in a main scanning direction and includes a plurality of light-receiving lenses 11 and a plurality of light-receiving elements. The plurality of light-receiving lenses 11 are arranged along the main scanning direction. The plurality of light-receiving elements are arranged linearly along the main scanning direction, and receive light transmitted through the plurality of light-receiving, lenses 11. The plurality of light-receiving lenses 11 are arranged to be separated from each other by a diameter of the light-receiving lens 11 or longer. A plurality of light-receiving elements 121 form at least one row or more of the reading lines L.

Abstract: An optical line sensor 1 includes an illumination unit 2, a light receiving unit 3, and a pair of holding members 4 separably attached to the light receiving unit 3 at both ends in a main scanning direction. The illumination unit 2 includes fitting portions (protrusions 25) at both ends in the main scanning direction. Each of the holding members 4 includes a fitted portion (hole 41). In a state where the fitting portion and the fitted portion are fitted, the illumination unit 2 is positioned so that the irradiation optical axis of light emitted from the illumination unit 2 overlaps the light receiving optical axis at a position substantially coinciding with a reading line of the light receiving unit 3 and is integrally held with the light receiving unit 3.

Abstract: An optical line sensor 1 includes an illumination unit 2, a light receiving unit 3, and a pair of holding members 4 separably attached to the light receiving unit 3 at both ends in a main scanning direction. The illumination unit 2 includes fitting portions (protrusions 25) at both ends in the main scanning direction. Each of the holding members 4 includes a fitted portion (hole 41). In a state where the fitting portion and the fitted portion are fitted, the illumination unit 2 is positioned so that the irradiation optical axis of light emitted from the illumination unit 2 overlaps the light receiving optical axis at a position substantially coinciding with a reading line of the light receiving unit 3 and is integrally held with the light receiving unit 3.

Abstract: One pixel unit including at least one light receiving element of a light receiving element array (photodiode array) and a light source have a one-to-one correspondence, and only when the light source emits light, the light beam is detected by at least one light receiving element (one pixel unit) corresponding to the light source. An illumination optical system includes a light guiding means for guiding to an inspection object by reducing an interval between optical axes of light beams emitted from a plurality of light sources in an arrangement direction of a plurality of the light sources.

Abstract: According to the present invention, a light source and one pixel unit formed of at least one light reception element among a light reception element array (photodiode array) are provided in a one-to-one correspondence, and a light beam is detected from at least one light reception element (one pixel unit) corresponding to the light source, only when the light source emits light. Therefore, only one collimated or further substantially condensed light beam is incident into “a foreign substance/defect” in an object to be inspected, and only scattered light can be separated by the light reception element and be detected. Accordingly, even when an object to be inspected has a light scattering property and is thick, “a foreign substance/defect” can be detected with a good signal to noise ratio (crosstalk is extremely low).

Abstract: A reflective member is disposed on the optical path from the linear light source to the lens array. An ultraviolet light blocking filter is provided closer to a light-receiving unit than the reflective member. A color filter is provided closer to the light-receiving unit than the ultraviolet light blocking filter. A light-receiving surface of the light-receiving unit has a first region opposed to the reflective member without the ultraviolet light blocking filter and the color filter interposed therebetween, a second region opposed to the reflective member and the ultraviolet light blocking filter without the color filter interposed therebetween, and a third region opposed to the reflective member, the ultraviolet light blocking filter, and the color filter.

Abstract: A reflective member is disposed on the optical path from the linear light source to the lens array. An ultraviolet light blocking filter is provided closer to a light-receiving unit than the reflective member. A color filter is provided closer to the light-receiving unit than the ultraviolet light blocking filter. A light-receiving surface of the light-receiving unit has a first region opposed to the reflective member without the ultraviolet light blocking filter and the color filter interposed therebetween, a second region opposed to the reflective member and the ultraviolet light blocking filter without the color filter interposed therebetween, and a third region opposed to the reflective member, the ultraviolet light blocking filter, and the color filter.