Method for manufacturing an optical sensor , the method comprising: - providing an optical sensor arrangement which comprises at least two optical sensor elements on a carrier , where the optical sensor arrangement comprises a light entrance surface at the side of the optical sensor elements facing away from the carrier , - forming a trench between two optical sensor elements in a vertical direction (z) which is perpendicular to the main plane of extension of the carrier , where the trench extends from the light entrance surface of the optical sensor arrangement at least to the carrier , - completely filling the trench with an opaque material , - forming electrical contacts for the at least two optical sensor elements on a back side of the carrier facing away from the optical sensor elements , - forming at least one optical sensor by dicing the optical sensor arrangement along the trench after the trench is filled with the opaque material, where - a handling substrate is arranged at the back side of the carrier during forming the trench and during filling the trench with the opaque material , the handling substrate being a tape that is expanded in a lateral direction (x) after forming the trench and before filling the trench with the opaque material , wherein the lateral direction (x) is parallel to the main plane of extension of the carrier , wherein - each optical sensor has an opaque coating, that is formed by the opaque material, at its side surfaces and comprises an optical sensor element , and - the light entrance surface is free of electrical contacts and at least partially free of the opaque material above the optical sensor elements . - providing an optical sensor arrangement which comprises at least two optical sensor elements on a carrier , where the optical sensor arrangement comprises a light entrance surface at the side of the optical sensor elements facing away from the carrier , - forming a trench between two optical sensor elements in a vertical direction (z) which is perpendicular to the main plane of extension of the carrier , where the trench extends from the light entrance surface of the optical sensor arrangement at least to the carrier , - completely filling the trench with an opaque material , - forming electrical contacts for the at least two optical sensor elements on a back side of the carrier facing away from the optical sensor elements , - forming at least one optical sensor by dicing the optical sensor arrangement along the trench after the trench is filled with the opaque material, where - a handling substrate is arranged at the back side of the carrier during forming the trench and during filling the trench with the opaque material , the handling substrate being a tape that is expanded in a lateral direction (x) after forming the trench and before filling the trench with the opaque material , wherein the lateral direction (x) is parallel to the main plane of extension of the carrier , wherein - each optical sensor has an opaque coating, that is formed by the opaque material, at its side surfaces and comprises an optical sensor element , and - the light entrance surface is free of electrical contacts and at least partially free of the opaque material above the optical sensor elements . <EOS>