| abstract |
A solid state light apparatus with a solar shielded heatsink ideally suited for traffic controls. The current state of the art solid state traffic signals utilize LED arrays encased in the existing plastic or metal traffic signal cases which were originally design for incandescent bulbs. Unlike LED's, incandescent bulbs are insensitive to high temperatures. As a result heat will build up on the LED die because of the limitations of the existing incandescent case design. The apparatus mounts the LED array directly to a louvered external heatsink in contact with the air outside of the traffic signal case facilitating the dissipation of heat generated from the LED die and from the sunlight shining on the case. For 25% of all signals (those facing west), during the late afternoon sunset the lensing system will focused the sunlight directly on the LED die raising the die temperature an additional 20 C. The louvered external heatsink dissipates this form of heat as well allowing the LED die to remain much cooler. |