Abstract: A light emitting diode comprising: a base substrate having a pair of electrodes; a reflection cup installed on the base substrate; a light emitting element arranged at a bottom of the reflection cup; and a resin sealant enclosing the light emitting element; wherein the light emitting element is electrically connected to the electrodes through an opening formed in the bottom of the reflection cup; wherein the reflection cup comprises a film body held in a cup shape and a metal film formed on a surface of the film body. This construction makes the control of light directivity easy and can produce light with a narrow directivity.

Abstract: A water purification system having multiple soil layers is disclosed. The system has at least two aerobic soil layers with an anaerobic soil layer positioned between the aerobic layers. Water passing through the system can pass in sequence from an aerobic layer, to an anaerobic layer, then to another aerobic layer, and so forth. The system can also include a water inlet, a water outlet, and an air distributor in at least one soil layer.

Abstract: A light emitting diode comprising: a base substrate having a pair of electrodes; a reflection cup installed on the base substrate; a light emitting element arranged at a bottom of the reflection cup; and a resin sealant enclosing the light emitting element; wherein the light emitting element is electrically connected to the electrodes through an opening formed in the bottom of the reflection cup; wherein the reflection cup comprises a film body held in a cup shape and a metal film formed on a surface of the film body. This construction makes the control of light directivity easy and can produce light with a narrow directivity.