The throw away lens that comes with the 12mm blank modules, they make a good beam but rob a little power, if used in a multi watt build they will melt, but at 300mw they stand up to their own energy absorption.
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Not wanting to get to far off topic, and this has been done before I know, but what's next? Will we see a stronger single mode 405 diode?
OK the 660 DVD's are single layer typically and 4.7 GB but......
I just read that the Bu-Ray is dual layer and holds 50 GB, I did not know it was that much.......it would be nice to see a 64x 405 burner.
Also there is more that can be done with laser disc.
The Holographic Versatile Disc (HVD), described in the ECMA-377 standard, has been in development by The Holography System Development (HSD) Forum using a green writing/reading laser (532 nm) and a red positioning/addressing laser (650 nm). It is to offer MPEG-2, MPEG-4 AVC (H.264), HEVC (H.265), and VC-1 encoding, supporting a maximum storage capacity of 6TB.[67] No systems corresponding to the Ecma International HVD standard have been released.[68] Because the Blu-ray Disc format is upgradable it poses challenges to the adoption of the HVD format.
6 TB WOW
4K Blu-ray discs and players will become available in the first quarter of 2016, having a storage capacity of up to 100 GB
Hmm, it seems the disc may not be dead yet.
This was interesting.
DATA SOURCE :
https://en.wikipedia.org/wiki/Blu-ray
https://en.wikipedia.org/wiki/DVD