High Thermal Stability and Wide Angle of White Light Chip-on-Board Package Using a Remote Phosphor Structure

High thermal stability and wide angle of a white light chip-on-board package using a remote phosphor structure was investigated. The junction and phosphor layer temperatures of the remote phosphor structure are lower than those of the conventional phosphor structure. Compared with the conventional structure, the luminous flux and luminous efficiency of the proposed phosphor structure are improved by more than 10% at an injection current of 1 A in the continuous wave mode. For the color temperature shift, the remote phosphor structure is more stable than the conventional one. In the radiation pattern, the remote phosphor structure is improved over 40°. Consequently, the remote phosphor structure is more suitable than the conventional phosphor structure in thermal stability and wide-angle lighting application.