A method of manufacturing a plurality of optical elements (140) comprising the steps of providing a substrate (120), and a tool (101) comprising a plurality of replication sections (106), each defining a surface structure of one of the optical elements (140), the tool (101) further comprising at least one contact spacer portion (112), aligning the tool (101) and the substrate (120) with respect to each other and bringing the tool (101) and a first side of the substrate (122) together, with replication material (124) between the tool (101) and the substrate (120), the contact spacer portion (112) contacting the first side of the substrate (122), and thereby causing the spacer portion (112) to adhere to the first side of the substrate (122), hardening the replication material (124), wherein the substrate (120) has yard line features (138) around at least a portion of the replication sections (106), the yard line features (138) containing the replication material (124) on a first side of the yard line with respect to the tool (101) and the substrate (120).