Multi beams from laser

The two beam shots are on the left mirror 2 and on the right mirror 1 straight out of the tube. Any thoughts? Could it be dirt in the end of the laser tube?

Your tube has shifted to a higher Transverse Electromagnetic Mode (TEM). Looks like the TEM02 pattern. Nothing to do but get a new tube I’m afraid.

Less than a month old☹️ Thanks for the advice though. How could that have happened🤔

Tubes can go bad quick if there is no or insufficient cooling. Or it’s possible it was just a bad / marginal tube to start with.

I hope you have an analog milli amp meter on it and have not been setting the digital power level to anything more than 30% without knowing the real power settings.

A very fast way to kill your laser power is to over power the tube( stock tube should get no more than 18ma MAX ) and the second way is to let the water temp get above 25C( should be 20-22C ).


The best protection for your tube is:

  • Use nonconductive coolant (distilled water)
  • Put a temp control in series with the water protect circuit that disables the laser above the operating temperature
  • Put a flow sensor in series with water protect circuit that disables the laser with lack of water flow
  • Use a milliamp meter to control & monitor power…

Hopefully fitting the 30 ma meter tomorrow. need to get a flow sensor and temp control.

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