Abstract: The present disclosure relates to music user interfaces. A device, comprising a display and a rotatable input mechanism, one or more processors, memory, and one or more programs, is described. In response to receiving the first user input, the one or more programs may include instructions for ceasing display of an audio playback user interface and displaying a first user interface of a first set of user interfaces. While displaying the user interface of the first set of user interfaces, the one or more programs may include instructions for: receiving a second user input representing a directional swipe in a second direction and, in response to receiving the second user input, ceasing display of the first user interface of a first set of user interfaces and displaying the audio playback user interface.

Abstract: Techniques for managing alerts are described. One or more alerts are received at the electronic device. In some embodiments, the device determines how notifications corresponding to the alerts should be output to the user.

Abstract: Techniques for managing alerts are described. One or more alerts are received at the electronic device. In some embodiments, the device determines how notifications corresponding to the alerts should be output to the user.

Abstract: The multiplexer/demultiplexer has a planar reflector, a planar first filter element and a planar second filter element offset from the first filter element in a first direction to receive light reflected and transmitted from a first location on the first filter element. The first and second filter elements have orthogonal surface normals. The reflector is parallel to the second filter element and is offset therefrom in a second direction, orthogonal to first direction, to receive light reflected and transmitted from a second location, offset from the first location in the second direction, on the first filter element. The first and second filter elements each transmit and reflect light in non-overlapping wavelength ranges, and one of them has a band-pass or band-stop transmission characteristic.

Abstract: The multiplexer/demultiplexer has a planar reflector, a planar first filter element and a planar second filter element offset from the first filter element in a first direction to receive light reflected and transmitted from a first location on the first filter element. The first and second filter elements have orthogonal surface normals. The reflector is parallel to the second filter element and is offset therefrom in a second direction, orthogonal to first direction, to receive light reflected and transmitted from a second location, offset from the first location in the second direction, on the first filter element. The first and second filter elements each transmit and reflect light in non-overlapping wavelength ranges, and one of them has a band-pass or band-stop transmission characteristic.

Abstract: A light modulation assembly and an image projector utilizing a plurality of such light modulation assemblies are disclosed. The light modulation assembly includes an optical element, a pre-polarization filter, an image modulator, and an analyzer polarization filter. The optical element has an input port for receiving a light beam. The optical element directs the light beam onto the pre-polarization filter that removes light having a linear polarization in a first direction. The light leaving the pre-polarization filter illuminates the image modulator. The light leaving the image modulator is filtered by the analyzer polarization filter to remove light having a linear polarization with a predetermined direction relative to the first direction. The light leaving the analyzer polarization filter exits the optical element through an output port. A plurality of such assemblies can be combined with a beam splitting assembly to provide an image projector.