Techhood "6W" 450nm laser module + PWM modulator

[Beamer123]

Hello my photonic friends!
This is a review of a chinese ebay engraving laser module for only 78USD with shipping. I did not know what to expect from this purchase. Now I know and want to inform anyone who is interested in cheap burning lasers from ebay or Aliexpress.

Shipping

-Ebay's "Orange Connex" is super fast. It arrived within 8 days in Germany.

The package includes:

- laser module with internal driver board, small fan, goggles (no good!), EU 12V AC/DC adapter, PWM regulator

Some details (given by seller)

- Output power: 6 Watt
- LD: NUBM08 (5W)
- TTL modulation upto 30 kHz
- Glass lens (no further spec.)
- Weight: 215g

Description

In general the laser seems to be well built. Nothing rattles or falls off. The labeling is completely wrong though. It works pretty well with the PWM regulator. At 5 kHz TTL frequency, the PWM mode corresponds perfectly with the output power. It is of course focusable.

Functionality

At the maximum power setting, the laser quickly warms up. Im measured 46°C at the housing after 3 minutes. During my first tests the laser reached 4,3W. After some use I was only able to measure 4,0W at the beginning. The output power drops constantly and very quickly. After 3 minutes the power decreases to 3,5W. I don't know what is causing that. Does anyone have an idea? Maybe it's due to the heating inside?

In addition I don't think the little fan has enough power to cool the laser down sufficiently.

Techhood says the module is supposed to do 5W in CW mode and 6W when pulsed. That's complete nonsense I guess.

Conclusion

I would be fine if the laser did a constant 4+W, but I am not happy with the power instability at all. I would not buy it again. These ebay engraving lasers have extraordinary power claims and I don't know where to buy a stable and up to spec burning laser module. Maybe I need to start building one myself..

Cheers

Philipp

 

[GSS]

Hi Beamer, I just have to ask, can you tell the power drop is somewhat obvious by beam or spot brightness?
You know where i'm going, meaning the pocket meter.
I'm tending to believe though because the rising heat issue.. Did you contact Techhood about maby some kind resolve? Be careful of giving feedback though They ban people from buying quickly

 

[Beamer123]

Hey GSS,
I know what you mean. I tested the laser after 3 minutes without using the lpm continuously right from the start. Result was the same. The lpm despite it‘s rather iffy reputation here seems to be working alright.
Techhood says I have the wrong measuring set-up or something .
The problem with these small laser modules probably is the insufficient heat dissipation capacity, since the diodes aren‘t produced in the same shady chinese „factories“.

 

[GSS]

Probably very true..
The 3 labby's I got were a 532's at 300mw and 200mw from "Aptlightingworld" which are basicly the same setups. The 300mw being bigger module and fan wise. But not to much heat issue at the power..
Anyway to speed the fan up on yours?

 

[Beamer123]

I asked Techhood to provide me with a G2 or G7 lens to get a little more power, but the instability can only get fixed with a more powerful fan and probably a different module housing. I thought an actively cooled laser would at least work better than a handheld laser, so maybe it‘s really the driver or the diode that are causing this problem. I just don‘t know..

 

[paul1598419]

The glass lens is likely a three element lens which will reduce your power by up to 25% over a good G2 lens. It would have been better if the diode had been a NUBM44 which can actually do 6+ watts easily. IDK, for only $78.00, it isn't the worst I've seen.