An optical waveguide circuit includes a first loss component for causing a diffraction loss of light propagating through an optical waveguide, and a second loss component provided at least one of before and after the first loss component, for causing a diffraction loss less than the diffraction loss in the first loss component to the light propagating through the optical waveguide. A latch assembly configured in accordance with one embodiment of the disclosure includes a latch and an actuator, each of which is movably coupled to a frame. The range and phase difference of the acoustic pulse between each of the detecting locations is determined. The extrinsic base further includes a first semiconductor material with a first bandgap and a second semiconductor material with a second bandgap that is smaller than the first bandgap. A plug connector is attached to the holder in a pre-assembly position. The plurality of users are assigned to a plurality of groups based on the data.