The invention provides a lighting device (1) comprising: —one or more light sources (10) configured to provide light source light (11); —a luminescent element (5) comprising an elongated luminescent body (100) having a radiation input face (111) for receipt of the light source light (11), the luminescent element (5) comprising a first luminescent material (120) for conversion of at least part of the light source light (11) into luminescent material light (8); —a light guide element (850), configured downstream of the first luminescent material (120), and configured to light guide at least part of the first luminescent material light (8); —a second luminescent material (1120), configured downstream of the first 10 luminescent material (120), at a first distance (d1) of at least 0.5 mm thereof, configured to convert one or more of (i) at least part of the light source light (11) and (ii) at least part of the first luminescent material light (8) into second luminescent material light (1128) having a spectral power distribution differing from a spectral power distribution of the first luminescent material light (8); 15—a light transmissive optical element (24) configured downstream of the light guide element (850), configured to receive at least part of the first luminescent material light (8) of the light guide element (850) and to receive at least part of the second luminescent material light (1128), and configured to transmit the received luminescent material light (8) and the received second luminescent material light (1128), and configured to beam shape at least part of the received luminescent material light (8), and to provide lighting device light (101) comprising one or more of the light source light (11), the first luminescent material light (8) and the second luminescent material light (1128).

The invention provides a method for producing a 3D item (1) by means of fused deposition modelling, the method comprising a 3D printing stage comprising layer- wise depositing an extrudate (321) comprising 3D printable material (201), to provide the 3D item (1) comprising 3D printed material (202), wherein the 3D item (1) comprises layers (322) of 3D printed material (202), wherein the method further comprises controlling a first temperature T.sub.1 of the 3D printable material (201) within a first temperature range, wherein the 3D printable material (201) comprises a thermoplastic host material (401) and a dopant material (410) in the range of 1-20 vol %, the dopant material (410) comprising polymeric flake-like particles having a metal coating, wherein the 3D printable material (201) has an optical property that irreversibly changes from a low-temperature optical property to a high-temperature optical property when increasing a temperature of the 3D printable material (201) over a change temperature T.sub.c, the optical property being selected from the group consisting of reflection, transmission, luminescence, absorption, and color, wherein the change temperature T.sub.c is within the first temperature range, wherein during at least a first part of the 3D printing stage the first temperature T.sub.1 is below the change temperature T.sub.c, and wherein during at least a second part of the 3D printing stage the first temperature T.sub.1 is above the change temperature T.sub.c.

An optical waveguide based side illuminating assembly having an elongated, side-emitting light waveguide, an optical protective coating surrounding the waveguide, an elongated base to which the waveguide is attached lengthwise along the elongated base, via the optical protective coating, a reflector between the optical protective coating and the elongated base and extending lengthwise along the base, and an elongated reinforcing structure embedded in the elongated base, or attached to an outer surface of the elongated base, and extending lengthwise along the elongated base. Other aspects are also described and claimed.

Embodiments of a light diffusing device with a color conversion layer are disclosed. Specifically the color conversion layer includes a luminophore that converts light from a higher wavelength to a lower wavelength.

A backlight unit and a display device in which the amount of light emitted to the top surface of the backlight unit is increased, are provided. The backlight unit includes light sources disposed on a printed circuit substrate, a reflective layer disposed on at least a partial area of an area in which the plurality of light sources are not disposed on the printed circuit substrate, a color conversion light guide layer disposed on the light sources, a non-color conversion light guide layer disposed on a surface of the color conversion light guide layer, a transparent film disposed on the color conversion light guide layer and the non-color conversion light guide layer and spaced apart from the light sources and the reflective layer, and light diffusion patterns disposed on a surface of the transparent film and corresponding to each light source.

A transparent luminescent solar concentrator (TLSC) is provided. The TLSC includes a luminophore and a waveguide that guides light emitted from the luminophore. The TLSC has a light utilization efficiency (LUE) of greater than or equal to about 1.

The invention relates to an area light decorative element (1) comprising an optically activatable symbol body (2) at least partially formed of a transparent optically activatable first material (9) and configured to emit visible light in response to the optically activatable symbol body (2) being excited with electromagnetic radiation in a predetermined first frequency range, a light element (3) consisting of a transparent material, wherein the optically activatable symbol body (2) is arranged in the light element (3), a touch-sensitive surface (4) disposed in a first area (5) of a surface of the light element (3) above the optically activatable symbol body (2) for detecting a touch of a user in the first area (5), and an illumination unit (6) which is arranged to emit visible light in a predetermined visible frequency range (22) into the light element (3) and, together with the visible light, also to emit electromagnetic radiation in the predetermined first frequency range into the light element (3).

A light generating system (1000) comprising a plurality of light sources (10) configured to provide light source light (11), an elongated luminescent body (100) having a first face (141) and a second face (142) defining a length (L) of the elongated luminescent body (100), the elongated luminescent body comprising one or more side faces (140), the elongated luminescent body (100) comprising a radiation input face (111) and the second face (142) comprising a first radiation exit window (112), wherein the radiation input face (111) is configured in a light receiving relationship with the plurality of light sources (10), wherein the elongated lumines-cent body (100) comprises luminescent material (120) configured to convert at least part of the light source light (11) into luminescent material light (8), and a beam shaping optical element (224).

Embodiments of the present invention include a system and method for detecting or sensing damage within a target material, as well as related devices. In some embodiments, a damage sensing system including a target material, an optical fiber embedded into the target material, where the optical fiber has an outer surface running the length of the optical fiber, a photosensitive receiver, and a triboluminescent coating coated on the optical fiber.

The invention provides a light generating system (1000) comprising: —a plurality of k light sources (10) configured to provide light source light (11), wherein k is a natural number of at least 5, wherein the light sources (10) are configured in an array (15), wherein the light sources (10) have inter-light source distances (d1); —an elongated luminescent body (100) having a length (L), the elongated luminescent body comprising one or more side faces (140), the elongated luminescent body (100) comprising a radiation input face (111) and a radiation exit window (112), wherein the radiation input face (111) is configured in a light receiving relationship with the plurality of light sources (10), wherein the elongated luminescent body (100) comprises luminescent material (120) configured to convert at least part of light source light (11) into luminescent material light (8), wherein the radiation exit window (112) has an angle (α) unequal to 0° and unequal to 180° with the radiation input face (111); —a body holder structure (2000), wherein the body holder structure (2000) comprises an elongated slit (205) for hosting the elongated luminescent body (100), wherein the elongated slit (205) comprises one or more slit side faces (2140); —n force applying elements (1300) configured to keep the elongated body (100) pushed against at least one of the one or more slit side faces (2140) of the elongated slit (205), wherein n is a natural number selected from the range of 0.01*L/mm-0.05*L/mm, wherein the length (L) is in mm, wherein n is at least 1, and wherein the inter-light source distance (d1) at the n force applying elements (1300) is larger than an average inter-light source distance (d1).