Apparatus and methods provide wireless, disposable, continuous pulse oximeter sensor technology, useful and beneficial for a number of applications including relatively extended periods of data collection, and/or packaged in compact and easy-to-use assemblies. Economic fabrication and use provides flexible methodologies that can reduce the overall costs of monitoring and collecting patient's physiological data, and provide relatively greater ease and comfort to the patient. A disposable wireless continuous pulse oximeter sensor has a reduced emitter-detector separation, a low-power frontend, and a low-cost processor that sends waveforms to a host device so that the host can calculate and display the parameters of interest. Complications created by the reduced distance between emitter and detector are minimized by using an emitter-detector assembly with an optically dark background, and a bandage for improved optical compliance.