Nova DC Laser Tube Pulse Anomoly - Pulse has a Ring and a Dot and looks like a Halo

Nova DC Laser Tube Pulse Anomoly - Pulse has a Ring and a Dot and looks like a Halo

Preface: This article covers a pulse anomaly that can occur due to the laser tube output or damaged optics


Typical Pulse Dot:

Red dot is not aligned (purposely) so that the pulse burn mark is easier to see. The pulse burn mark should be concentrated without scatter or halo artifacts. It may not appear perfectly round due to how the tape burns. If it shows signs of scatter or major deformation, it could be a dirty\fouled mirror or bad optic.



Malformed Pulse:

Notice the Halo ring around the pulse dot. That is not normal. This pulse was done at the mirror 3 entry


Same machine, pulsed into wood right at the exit of the laser tube showing the oversized pulse pattern:



Inspect Optics:

Before pulsing any further, lets do a visual check of the following:
1. Laser Tube Exit.
2. Beam Combiner

3. Mirror 1

4. Mirror 2


If the above visual checks show that a mirror or lens is dirty, then clean them or replace if necessary.
If no anomalies are found then proceed to the next step of pulse checking along the laser path.

The RECI tube in the Nova 35-80W has a replaceable tube exit lens. Found here and here.

Steps to Check for the source:

Work through this list to find the source of the issue. Starting at the tube exit and pulsing in the different locations to see when the anomaly shows up. For information on how to Pulse the laser, refer to the reference articles at the bottom of this article.

1. Pulse on wood at the tube exist between the tube and the beam combiner location
2. Pulse on wood at between the beam combiner and mirror 1
3. Pulse between mirror 1 and mirror 2
4. Pulse between mirror 2 and mirror 3

If the anomaly shows up in between steps, then the prior device is suspect and should be remediated.  You can email support@thunderlaserusa.com for more information and guidance.

Reference Articles: