analog to ttl

No matter how you set all this up, with more or less hysteresis, appropriate positive feedback to drive it rapidly to the rails, etc., there is going to be a resulting duty cycle of ON versus OFF that is decided by how you set up things. And this may impact the visual effect of your laser display, regardless of the fact that the power is always neatly full-on or full-off. It seems you may want some method of controlling this aspect, so that you can adjust it to what you need.

Perhaps even an independent control for each of the two hysteresis voltages would be nice? Or else independent control of the center and width of the hysteresis band?

Jon

or Schmitt triggers...

or Schmitt triggers made with comparators...

Good point for a beginner.

But a digital family catalog will have no listing for anything called a "comparator" in the analog sense. The digital comparator works on bit patterns. It will have a listing for Schmitt Trigger.