Method of reducing effect of stray light in optical sensor

An optical sensor comprising:

• a light emitting element that emits and outputs light;
• a light receiving element that receives light outputted from the light emitting element and reflected by an object to be irradiated;
• a substrate on which the light emitting element and the light receiving element are mounted;
• an electrically conductive pattern formed on the substrate, the electrically conductive pattern including a land electrically connected to an electrode of the light receiving element;
• a resist arranged as a layer above the electrically conductive pattern or the substrate;
• a light shielding layer provided as a layer above the resist;
• and
• a light shielding region formed by a portion of the land and a portion of the light shielding layer overlapping in the direction of the normal of a mounting surface of the substrate, the light shielding region thereby configured to shield stray light directed towards the light receiving element from the substrate,
• wherein, when viewed in the direction of the normal of the mounting surface of the substrate, there is a region surrounding the light emitting element without the light shielding layer.

An optical sensor comprising:

• a light emitting element that emits and outputs light;
• a light receiving element that receives light outputted from the light emitting element and reflected by an object to be irradiated;
• a substrate on which the light emitting element and the light receiving element are mounted;
• an electrically conductive pattern formed on the substrate, the electrically conductive pattern including a first land electrically connected to an electrode of the light emitting element and a second land electrically connected to an electrode of the light receiving element;
• a resist arranged as a layer above the electrically conductive pattern or the substrate;
• and
• a light shielding layer provided as a layer above the resist,
• wherein, in the direction of the normal of a mounting surface of the substrate, a portion of the first land and a portion of the light shielding layer are overlapped and a portion of the second land and a portion of the light shielding layer are overlapped, and
• wherein, when viewed in the direction of the normal of the mounting surface of the substrate, there is a region surrounding the light emitting element without the light shielding layer.

A sheet conveyance apparatus comprising:

• a conveyance roller that conveys a sheet along a conveyance path;
• and
• an optical sensor configured to detect the sheet conveyed by the conveyance roller, wherein the optical sensor includes:
• a light emitting element that emits and outputs light;
• a light receiving element that receives light outputted from the light emitting element and reflected by an object to be irradiated;
• a substrate on which the light emitting element and the light receiving element are mounted;
• an electrically conductive pattern including a land electrically connected to an electrode of the light emitting element and formed on the substrate;
• a resist arranged as a layer above the electrically conductive pattern or the substrate;
• a light shielding layer provided as a layer above the resist;
• and
• a light shielding region formed by a portion of the land and a portion of the light shielding layer overlapping in the direction of the normal of a mounting surface of the substrate, the light shielding region thereby configured to shield stray light directed towards the substrate from the light emitting element,
• wherein, when viewed in the direction of the normal of the mounting surface of the substrate, there is a region surrounding the light emitting element without the light shielding layer.

An image forming apparatus comprising:

• a conveyance roller that conveys a sheet along a conveyance path;
• an optical sensor configured to detect the sheet conveyed by the conveyance roller;
• and
• an image former that forms an image on the sheet, wherein the optical sensor includes:
• a light emitting element that emits and outputs light;
• a light receiving element that receives light outputted from the light emitting element and reflected by an object to be irradiated;
• a substrate on which the light emitting element and the light receiving element are mounted;
• an electrically conductive pattern including a land to be electrically connected to an electrode of the light emitting element and formed on the substrate;
• a resist arranged as a layer above the electrically conductive pattern or the substrate;
• a light shielding layer provided as a layer above the resist;
• and
• a light shielding region formed by a portion of the land and a portion of the light shielding layer overlapping in the direction of the normal of a mounting surface of the substrate, the light shielding region thereby configured to shield stray light directed towards the substrate from the light emitting element,
• wherein, when viewed in the direction of the normal of the mounting surface of the substrate, there is a region surrounding the light emitting element without the light shielding layer.