A multi-optical axis sensor according to an embodiment of the present invention comprises: a light-transmitting unit comprising a plurality of light-transmitting elements; a light-receiving unit comprising a plurality of light-receiving elements which are arranged to respectively face the light-transmitting elements and respectively receive light from the light-transmitting elements; and an indicator light indicating a light incidence state or a light blockage state of the light-receiving unit, wherein, before a muting state that invalidates the detection function of the multi-optical axis sensor is detected, the light-transmitting unit or the light-receiving unit may operate the indicator light in a light incidence/blockage mode indicating the light incidence state or the light blockage state, and when the muting state is detected, the light-transmitting unit or the light-receiving unit may switch the operation mode of the indicator light from the light incidence/blockage mode to the muting mode indicating the muting state.

In a lighting system an optical fiber includes a light incident portion, a light emerging portion, and a wavelength-converting portion. The wavelength-converting portion is provided between the light incident portion and the light emerging portion. The wavelength-converting portion contains a wavelength-converting element which is excited by excitation light and amplifies a spontaneous emission of light, having a longer wavelength than the excitation light, with an amplified spontaneous emission of light. A first light source unit makes the excitation light incident on the light incident portion. A second light source unit makes seed light, which causes the wavelength-converting element excited by the excitation light and the amplified spontaneous emission of light to produce a stimulated emission of light, incident on the light incident portion. A lighting unit, into an external space, light emerging from the light emerging portion of the optical fiber.

In a lighting system an optical fiber includes a light incident portion, a light emerging portion, and a wavelength-converting portion. The wavelength-converting portion is provided between the light incident portion and the light emerging portion. The wavelength-converting portion contains a wavelength-converting element which is excited by excitation light and amplifies a spontaneous emission of light, having a longer wavelength than the excitation light, with an amplified spontaneous emission of light. A first light source unit makes the excitation light incident on the light incident portion. A second light source unit makes seed light, which causes the wavelength-converting element excited by the excitation light and the amplified spontaneous emission of light to produce a stimulated emission of light, incident on the light incident portion. A lighting unit, into an external space, light emerging from the light emerging portion of the optical fiber.

A lighting apparatus includes a light source, a light passing cover, a back cover and a rim frame. The light source is used for emitting a light. The light passing cover has a first ladder edge. The rim frame has an inner frame and a light source holder. The back cover, the surface rim and the light passing cover define a concealed space. The light source is disposed in the light source holder in the concealed space. The inner frame defines a light opening for the light to escape from the lighting apparatus. The inner frame has a second ladder edge surrounding the light opening. The first ladder edge and the second ladder edge are pressed by the back cover to press to each other. Multiple ladder protrusion surfaces between the first ladder edge and the second ladder edge prevent water to enter the concealed space.

A lighting apparatus includes a light source, a light passing cover, a back cover and a rim frame. The light source is used for emitting a light. The light passing cover has a first ladder edge. The rim frame has an inner frame and a light source holder. The back cover, the surface rim and the light passing cover define a concealed space. The light source is disposed in the light source holder in the concealed space. The inner frame defines a light opening for the light to escape from the lighting apparatus. The inner frame has a second ladder edge surrounding the light opening. The first ladder edge and the second ladder edge are pressed by the back cover to press to each other. Multiple ladder protrusion surfaces between the first ladder edge and the second ladder edge prevent water to enter the concealed space.

An LED light bulb in the shape of an incandescent light bulb having an engagement end that is insertable into a light fixture socket; a diffuser provided at a second opposed end of the LED light bulb and a heat sink that extends from the engagement end to the diffuser. The heat sink comprises a plurality of fins extending in the axial direction, the fins forming an exterior surface of the LED lightbulb, the heat sink having an axial inner end located at the engagement end and an axial outer end located at an axial inner end of the diffuser.

An LED light bulb in the shape of an incandescent light bulb having an engagement end that is insertable into a light fixture socket; a diffuser provided at a second opposed end of the LED light bulb and a heat sink that extends from the engagement end to the diffuser. The heat sink comprises a plurality of fins extending in the axial direction, the fins forming an exterior surface of the LED lightbulb, the heat sink having an axial inner end located at the engagement end and an axial outer end located at an axial inner end of the diffuser.

A device includes a light source, a waveguide layer, and a light director layer. The light source emits illumination light. The waveguide layer includes a cladding layer and an optical waveguide. The cladding layer provides a top planar surface of the waveguide layer and the optical waveguide is immersed in the cladding layer and includes a light input coupler. The light director layer includes a bottom planar surface that is disposed on the top planar surface of the waveguide layer. The light director layer also includes a light director that receives and directs the illumination light to the light input coupler as shaped light. The light director is configured to tilt the illumination light to give the shaped light a tilt angle with respect to the light input coupler.

A device includes a light source, a waveguide layer, and a light director layer. The light source emits illumination light. The waveguide layer includes a cladding layer and an optical waveguide. The cladding layer provides a top planar surface of the waveguide layer and the optical waveguide is immersed in the cladding layer and includes a light input coupler. The light director layer includes a bottom planar surface that is disposed on the top planar surface of the waveguide layer. The light director layer also includes a light director that receives and directs the illumination light to the light input coupler as shaped light. The light director is configured to tilt the illumination light to give the shaped light a tilt angle with respect to the light input coupler.

According to one aspect, a waveguide comprises a waveguide body having a coupling cavity defined by a coupling feature disposed within the waveguide body. A plug member comprises a first portion disposed in the coupling cavity and an outer surface substantially conforming to the coupling feature and a second portion extending from the first portion into the coupling cavity. The second portion includes a reflective surface adapted to direct light in the coupling cavity into the waveguide body.