Abstract: The present disclosure relates to an apparatus that can be used to humidify a stream of air that may be delivered to a patient for respiratory assistance during Positive Airway Pressure (PAP) therapy. The apparatus includes a humidification chamber and compartment that receives the humidification chamber in which the humidification chamber is secured in the compartment to enhance thermal engagement, for example, between a heater plate of the compartment and a heater base of the humidification chamber.

Abstract: An optical filter and method of filtering uses a multi-mode waveguide having a first number n modes and a second waveguide having a different number m modes are coupled in series, where n and m are integers and n>m, and where the interaction of different modes at the interface of the two waveguides filters an optical signal propagating through the waveguides to provide a desired response characteristic. A lateral offset between the central axes of the waveguides at their interface is changed to control the response of the filter. For a multiple wavelength optical source uses, a filter coupled in the optical cavity including a laser gain medium provides interaction of different modes at the interface of waveguides in the filter to filter an optical signal propagating in the cavity thereby providing an output signal with multiple peaks at different wavelengths with a predetermined spacing.