Abstract:
An LED unit (20) having increased light output. The LED unit (20) includes a submount substrate (22) having a cavity (24). An LED chip (30) is electrically mounted within the cavity (24) and a phosphor layer (34) is deposited in the cavity (24) that converts blue light from the LED chip (30) into white light suitable for a vehicle headlight (10). The walls of the cavity (24) are metalized (40) to increase the light output intensity. In one embodiment, a clear protective layer (46) is deposited in the cavity (24) over the phosphor layer (34).
Abstract:
An LED headlamp assembly (10) for a vehicle. The headlamp assembly (10) includes a plurality of LED units (14) mounted to a common carrier (16), where the LED units (14) include one or more LEDs and generate white light. The headlamp assembly (10) further includes a headlamp housing (28) that is mounted to the vehicle by a mounting frame (52). The carrier (16) is sealed to' the housing (28) by a flexible bellows (34). An outer lens (26) is mounted to the housing (28) so that the LED units (14) are positioned within a sealed compartment (42). A backside of the carrier (16) outside of the sealed compartment (42) includes fins (46) or other heat sinking devices t o remove heat generated b y the LED units (14). The frame (52) allows convective air to flow around the heat sink (46) to remove heat from the LED units (14). A series of actuators (56) and/or pivots (58) are mounted to the frame (52) and to the carrier (16) so that the carrier (16) can be moved on at least one axis to adjust the direction of the LED headlamp assembly (10).
Abstract:
A vehicle headlight (12) that employs a plurality of LED units (38) that emit white light. Each LED unit (38) employs chip-on-board technology where LED semiconductor chips (64) are mounted directly to a submount substrate (56) using solder or stud bumps (60). An elongated lens (28) is molded over the LED unit (38) in contact with a base substrate (48). Light emitted from the semiconductor chip (64) is reflected and directed by the lens (28) to generate a beam of light (58). Some of the light emitted from the LED semiconductor chip (64) is redirected back to the submount substrate (56) to be reflected back into the lens (28) to increase the light intensity of the LED unit (38). Several of the elongated lens (28) and associated LED units (38) are optically glued to a single prism (24) that collects all of the light beams from all of the LED units (38).