A wearable member may include a plurality of energy transmitters that are arranged on a surface of the wearable member, each of the energy transmitters being configured to project energy into tissue of a user. A wearable member may include a plurality of energy receivers each of which is configured to generate a signal based on a received portion of the energy that is projected by one or more of the energy transmitters and reflected by the tissue of the user, wherein at least one of the energy transmitters and the energy receivers are multi-dimensionally arranged on the wearable member such that energy reflected by the tissue of the user at locations that are multi-dimensionally different is incident on the plurality of energy receivers. The processor may be configured to calculate a biological metric based on signals generated by at least part of the plurality of energy receivers.