An optical device is mounted to an electronic circuit having a main face with at least one light source. The optical device is made from a block which includes, for each light source, a corresponding opening that passes through the block. The opening includes a cylindrical part with a threading on an inside surface.

Holographic energy directing systems may include a waveguide array and a relay element. Disclosed calibration approaches allows for mapping of energy locations and mapping of energy locations to angular direction of energy as defined in a four-dimensional plenoptic system. Distortions due to the waveguide array and relay element may also be compensated.

Devices that include light assemblies for providing visual feedback to users that operate the electronic devices. In some instances, the devices comprise voice-controlled devices and, therefore, include one or more microphones for receiving audible commands from the users. After receiving a command, for instance, one such voice-controlled device may cause a corresponding light assembly of the device to illuminate in some predefined manner. This illumination may indicate to the user that device has received the command. In other instances, the devices may illuminate the lighting assembly for an array of other purposes. For instance, one such device may illuminate the corresponding light assembly when powering on or off, playing music, outputting information to a user (e.g., via a speaker or display), or the like.

A waveguide assembly comprising a first waveguide, and a second waveguide designed as a dielectric multimodal waveguide, and a waveguide transition for transmitting an electromagnetic wave between the first waveguide and the second waveguide, the waveguide transition having a dielectric waveguide piece which is between the first waveguide and the second waveguide. The dielectric waveguide piece is capable of guiding a smaller mode number than the second waveguide, at least in a front section, facing the first waveguide.

A backlight (100) for an image forming device (70) includes spaced-apart front and back optical reflectors (20, 10) defining an optical cavity (18) therebetween, and at least one light source (15) for emitting light into the optical cavity. The front optical reflector (20) is disposed between the image forming device and the back optical reflector (10). For substantially normally incident light and for non-overlapping first (e.g. visible light) and second (e.g. infrared) wavelength ranges, the front optical reflector (20) may transmit (80c) at least 70% of light (80a) for each wavelength in the first wavelength range, and may reflect (90b) at least 70% of light (90a) for each wavelength in the second wavelength range. The back optical reflector (10) may reflect (80b) at least 70% of light for each wavelength in the first wavelength range, and may transmit (90c) at least 70% of light (90b) for each wavelength in the second wavelength range. The light (80a, 90a) emitted by the at least one light source (15) has at least one wavelength in the first wavelength range and at least one wavelength in the second wavelength range.

Backlight module, light guide plate, and preparation method for conductive hydrogel thereof. Main body of light guide plate is optical-glass material. Cavity is provided in light guide plate, filled with conductive hydrogel. Either end of light guide plate is provided with electrode electrically connected to conductive hydrogel in cavity. When not electrified, conductive hydrogel is in liquid state, when electrified, conductive hydrogel in cavity changes to gel state. Microcrystal particles are added to conductive hydrogel to improve light refection function and light diffuse reflection function of light guide plate and backlight module, to allow more light rays to penetrate through light guide plate to improve luminous efficacy. Addition of quantum dots or fluorescent powder to conductive hydrogel can further increase color gamut of backlight, such that liquid crystal display device has better effect.

In various embodiments, an illumination apparatus features spatially separated input and output regions, a light source, a phosphor for light conversion, and an out-coupling structure.

A backlight according to an embodiment includes a reflecting portion, a nonwoven fabric disposed opposing the reflecting portion, a reflective polarization portion disposed along a surface of the nonwoven fabric opposite to the surface of the nonwoven fabric opposing the reflecting portion, a side wall surrounding a cavity formed between the reflecting portion and the nonwoven fabric, and a light source disposed proximate the side wall and configured to illuminate light in the cavity, wherein a haze value of the nonwoven fabric is 90% or greater, an effective transmittance of the nonwoven fabric is 0.8 or greater, and a basis weight of the nonwoven fabric is 60 g/m.sup.2 or greater.

An optical rotary joint includes first and second hollow tubular members. At least one of the first and second hollow tubular members is rotatable about a common longitudinal axis. A ring shaped optical waveguide between the first and second hollow tubular members includes first and second axial faces oriented perpendicular to the common longitudinal axis, an inner circumferential edge facing the outer circumference of the first hollow tubular member, an outer circumferential edge facing the inner circumference of the second hollow tubular member, and a circular light scattering channel formed in the first and/or second axial faces. First optical emitters are arranged to face the outer or inner circumferential edge. Second optical emitters are arranged to face the channel. A first optical receiver is arranged to face the outer or inner circumferential edge. A second optical receiver is arranged to face the channel.

Holographic energy directing systems may include a waveguide array and a relay element. Disclosed calibration approaches allows for mapping of energy locations and mapping of energy locations to angular direction of energy as defined in a four-dimensional plenopic system. Distortions due to the waveguide array and relay element may also be compensated.