Abstract: In a first aspect of the present invention, a lighting device includes a light-emitting element, a phosphor layer including a phosphor and spaced from the light-emitting element, and a light-transmitting layer with thermal conductivity that is higher than thermal conductivity of the phosphor layer, the light-transmitting layer disposed in contact with the phosphor layer. It is disclosed that the phosphor layer has first and second surfaces opposite to each other. In some embodiments, the light-transmitting layer that transmits light emitted from the light-emitting element is disposed on the first surface of the phosphor layer. It is also disclosed that the first light-transmitting layer that transmits light emitted from the light-emitting element is disposed on the first surface of the phosphor layer and a second light-transmitting layer that transmits visible light is disposed on the second surface of the phosphor layer.

Abstract: A laser light source according to the present invention includes a laser element that outputs a fundamental wave; a wavelength conversion element into which the fundamental wave is input and that converts at least a part of the fundamental wave input therein to a converted wave having a wavelength shorter than the wavelength of the fundamental wave; a waveguide that attenuates a component of the fundamental wave included in an output wave from the wavelength conversion element; and a diffraction grating that is formed on the waveguide and feeds back the fundamental wave output from the wavelength conversion element to lock the wavelength or the frequency of the fundamental wave output from the laser element. The diffraction grating is formed at a position determined taking into account an amount by which the fundamental wave is attenuated in the waveguide.

Abstract: In a first aspect of the present invention, a lighting device including a metal plate, an electrical insulation layer that is smaller in size than an outline of the metal plate and arranged on an upper surface of the metal plate, a light-emitting element mounted on the electrical insulation layer, and a first connecting electrode and a second connecting electrode electrically connected to the light-emitting element and arranged on the electrical insulation layer.

Abstract: In a first aspect of the present invention, it is suggested that a mounting method for mounting light-emitting elements as evenly as possible in a mounting area of a lighting device may permit increased number of light-emitting elements. In a second aspect of the present invention, a lighting device including a substrate with a circular mounting area, a plurality of light-emitting elements configured to be positioned at centers of equal smaller circular areas that are calculated to be equal in size in the circular mounting area, the equal smaller circular areas being equal in size to each other and set as large as possible without an overlapping portion in the circular mounting area, a total area of the equal smaller circular areas being smaller than the circular mounting area, and the light-emitting elements and the equal smaller circular areas being the same in number is suggested.

Abstract: In accordance with a first aspect of the present inventive subject matter, a lighting device includes light-emitting elements arranged in lines that are extended in parallel with one another, the light-emitting elements being divided into groups each including the same number of light-emitting elements, a first connecting electrode is disposed adjacent to one end portion of the lines extended, a second connecting electrode is disposed adjacent to another end portion of the lines extended, and the light-emitting elements within each group are electrically connected in series with one another by metallic wires and electrically connected in series to the first connecting electrode and to the second connecting electrode. The groups each include the same number of light-emitting elements that are electrically connected in parallel between the first connecting electrode and the second connecting electrode.

Abstract: In some embodiments, a light source including a first electrode that includes a projection and a depression, a second electrode including a projection and a depression, an insulating layer disposed between the first electrode and the second electrode, and a light-emitting element straddling the insulating layer and disposed on the projection of the first electrode and on the projection of the second electrode. In other embodiments, a lighting device including a base that includes a first terminal and a second terminal that are configured to be electrically connected to the light source to supply current to the light-emitting element. In some embodiments, the lighting device is a lighting bulb, and in other embodiments, the lighting device is tube-shaped.

Abstract: A light-emitting device includes a phosphor plate including an upper surface, a lower surface opposite to the upper surface, a peripheral side surface extending between a peripheral edge of the upper surface and a peripheral edge of the lower surface of the phosphor plate, a light-emitting element including an upper surface, a lower surface opposite to the upper surface, a peripheral side surface extending between a peripheral edge of the upper surface and a peripheral edge of the lower surface of the light-emitting element. The lower surface of the phosphor plate includes a concave that is filled with an adhesive and the lower surface of the phosphor plate is disposed on the upper surface of the light-emitting element. The phosphor plate may contain a first phosphor, and the adhesive filled in the concave that is provided at the lower surface of the phosphor plate may include a second phosphor.

Abstract: A light-emitting device includes a mounting area that includes a first end and a second end opposite to the first end, a first electrode group disposed adjacent to the first end of the mounting area, a second electrode group disposed adjacent to the second end of the mounting area, a plurality of files each in that a plurality of light-emitting elements are arranged in the mounting area to extend from a vicinity of the first end of the light-emitting area to a vicinity of the second end of the mounting area and electrically connected in series with each other of the light-emitting elements in each file. Light-emitting elements included in two or more files can be a light-emitting block to be lighted together through electrodes of the first electrode group and the second electrode group.

Abstract: A light-emitting device includes a rectangular substrate, a through-holes that is in a shape of a quarter of circle provided in two corners or four corners of the substrate, a pair of electrodes provided along short sides of the substrate and electrically connected to the through-hole(s) that is adjacently disposed to each of the electrodes. Each of the through-holes is covered by a cover that is in a shape of a quarter of circle.