LED illuminating device comprising light emitting device including LED chips on single substrate
A light emitting device includes: a ceramic substrate; a plurality of LED chips; a printed resistor(s) connected in parallel with the plurality of LED chips; a dam resin made of a resin having a low optical transmittance; a fluorescent-material-containing resin layer; and an anode-side electrode and a cathode-side electrode, (a) which are provided on a primary surface of the ceramic substrate so as to face each other along a first direction on the primary surface and (b) which are disposed below at least one of the dam resin and the fluorescent-material-containing resin layer. With the configuration in which a plurality of LEDs, which are connected in a series-parallel connection, are provided on a substrate, it is possible to provide a light emitting device which can achieve restraining of luminance unevenness and an improvement in luminous efficiency.
1. An LED illuminating device comprising:
a mounting surface;
a light emitting device mounted on said mounting surface, including:
(i) a substrate having a primary surface and a back surface that is faced toward said mounting surface,
(ii) a plurality of LED chips positioned around a center of the primary surface of the substrate,
(iii) a resin frame formed on the primary surface of the substrate and provided annularly so as to surround a mounting area in which the plurality of LED chips are provided, the resin frame having light reflectivity,
(iv) a sealing resin provided on the mounting area, and
(v) an anode-side electrode land and a cathode-side electrode land which are electrodes electrically connected to a voltage supply circuit in said LED illuminating device and to the plurality of LED chips, the anode-side electrode land and the cathode-side electrode land being provided on the primary surface of the substrate and outside the resin frame; and
a lens located above the light emitting device and apart from the sealing resin.
2. The LED illuminating device of claim 1 , further comprising:
a first external wiring line connected to the anode-side electrode land, extending from the anode-side electrode land to beneath said mounting surface; and
a second external wiring line connected to the cathode-side electrode land, extending from the anode-side electrode land to beneath said mounting surface.
3. The LED illuminating device of claim 1 , wherein said mounting surface has a round shape in a top view.
4. The LED illuminating device of claim 3 , further comprising a radiator fin provided around said LED illuminating device.
5. The LED illuminating device of claim 1 , wherein the substrate has a rectangular shape in the top view.
6. The LED illuminating device of claim 5 , wherein the substrate has a longer side of 15 mm and a shorter side of 12 mm.
7. The LED illuminating device of claim 5 , wherein the anode-side electrode land and the cathode-side electrode land are located near corners of the substrate.
8. The LED illuminating device of claim 7 , wherein the anode-side electrode land is opposite to the cathode-side electrode land with respect to the sealing resin.
9. The LED illuminating device of claim 1 , wherein the resin frame has a circular shape in a top view.
10. The LED illuminating device of claim 9 , wherein the sealing resin contacts with the resin frame.
11. The LED illuminating device of claim 10 , wherein the sealing resin has a dome shape that projects upward in a cross section view.
12. The LED illuminating device of claim 11 , wherein the peak of the dome shape is higher than the top of the resin frame.
13. The LED illuminating device of claim 12 , wherein the resin frame has a dome shape in a cross section view.
14. The LED illuminating device of claim 10 , wherein the anode-side electrode land is opposite to the cathode-side electrode land with respect to the sealing resin.