LITCHR

1. fixed: a signal light that shows continuously, in any given direction, with constant luminous intensity and colour. (IHO Dictionary, S-32, 5th Edition, 2780)
2. flashing: a rhythmic light in which the total duration of light in a period is clearly shorter than the total duration of darkness and all the appearances of light are of equal duration. (IHO Dictionary, S-32, 5th Edition, 2783)
3. long-flashing: a flashing light in which a single flash of not less than two seconds duration is regularly repeated. (IHO Dictionary, S-32, 5th Edition, 2796)
4. quick-flashing: a light exhibiting without interruption very rapid regular alternations of light and darkness. (IHO Dictionary, S-32, 5th Edition, 2803)
5. very quick flashing: a flashing light in which flashes are repeated at a rate of not less than 80 flashes per minute but less than 160 flashes per minute.
6. ultra quick flashing: a flashing light in which flashes are repeated at a rate of not less than 160 flashes per minute.
7. isophased: a light with all durations of light and darkness equal. (IHO Dictionary, S-32, 5th Edition, 2779)
8. occulting: a rhythmic light in which the total duration of light in a period is clearly longer than the total duration of darkness and all the eclipses are of equal duration. (IHO Dictionary, S-32, 5th Edition, 2801)
9. interrupted quick flashing: a quick light in which the sequence of flashes is interrupted by regularly repeated eclipses of constant and long duration. (IHO Dictionary, S-32, 5th Edition, 2790)
10. interrupted very quick flashing: a light in which the very rapid alterations of light and darkness are interrupted at regular intervals by eclipses of long duration. (IHO Dictionary, S-32, 5th Edition, 2792)
11. interrupted ultra quick flashing: a light in which the ultra quick flashes (160 or more per minute) are interrupted at regular intervals by eclipses of long duration. (IHO Dictionary, S-32, 5th Edition, 2791)
12. morse: a rhythmic light in which appearances of light of two clearly different durations are grouped to represent a character or characters in the Morse code. (IHO Dictionary, S-32, 5th Edition, 2798)
13. alternating: a signal light that shows, in any given direction, two or more colours in a regularly repeated sequence with a regular periodicity. (IHO Dictionary, S-32, 5th Edition, 2770)