The lamp for generating light, comprises a semiconductor light emitting element for emitting light, a fluorescent material, provided away from the semiconductor light emitting element, a first optical member operable to focus the light generated by the semiconductor light emitting element on the fluorescent material; and a second optical member having an optical center at a position where the fluorescent material is provided, operable to emit light from the fluorescent material based on the light focused by the first optical member to an outside of the lamp. The lamp is used as a headlamp in a vehicle, and the second optical member emits the light from the fluorescent material to the outside of the lamp, so that the second optical member form sat least one of a part of a cut line that defines a boundary between a bright region and a dark region of the headlamp.
An illuminating unit having a plurality of light emitting devices and collimators and a projection type image display apparatus using the same are provided. The illuminating unit includes: a plurality of light emitting devices which output light beams of predetermined wavelengths; a plurality of collimators, each having a parabolic reflection surface for reflecting the light beam in a predetermined direction, a mounting section for locating the light emitting device at the focal point of the parabolic reflection surface, a light output surface opposite to the parabolic reflection surface, and a light guide section for guiding the light beam reflected from the parabolic reflection surface to the light output surface; and one or more fixing members having two or more steps for mounting the light emitting devices and the collimators on their top surface. A plurality of light emitting devices and collimators are efficiently arranged in a small space. Therefore, thermal concentration can be reduced and heat can be effectively discharged.
