Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4890030 | Metal halide discharge lamp with arc tube temperature equalizing means | William M. Keeffe | 1989-12-26 |
| 4859899 | Metal-halide lamp having heat redistribution means | William M. Keeffe, Robert J. Karlotski, James C. Morris | 1989-08-22 |
| 4825127 | Metal halide discharge lamp for plant growing | William M. Keeffe | 1989-04-25 |