Cheap "analogo" and TTL RGB laser modules off ebay.

In my quest to find cheap rgb modules I stumbled across these modules on ebay. To date I have purchased two. One was a 400mW TTL module and the new one I picked up this weekend is a 400mW "analogo" module.

Attachment 38662

The cases for both of these modules are the same as are the diode and optic mounts. The TTL version only has one fan aimed at the green diode while the analog version has TWO. The optics and diodes are somewhat adjustable, but there is a ton of red glue inside so you're not going to have fun trying this.

The TTL Version has a terrible design flaw where the vent on the side of the laser is right behind the dichros. As a result, quite a bit of green and red light get through. I measured it and it's about 1mW according to my meter.
Attachment 38658
The analog module has this vent atop of the dichros so while you can peer in and see light... no real visible light escapes.


Attachment 38659

When I got these, I wondered if they had an IR filter for the 532nm green. I tested this by placing an ir filter I purchased from ebay in front of the module then checking the new power reading. The output dipped by a very small amount (1-2 mW) so either these do have an IR filter.. or this IR filter I purchased from ebay is just a piece of glass :)



I was also curious about claimed vs real power. Here's an image with my findings of the analog version using an ophir 20-c-a-1-y head. Either this head is out of tune.. or I didn't get all the mW I paid for:
Attachment 38661


Someone requested some beam profile pics so I took a few from 10m. The unit claims to have < 2.5mrad divergence.
Attachment 38660
I'm pretty happy with how well aligned the diodes are on my analog unit. The TTL unit's color alignment is acceptable.. but they noticeably separate even after 2.5m.


I haven't done any linear tests yet nor have I checked out the driving circuit yet.

Thank you for posting this initial review, Macpod!

Its amazing how this hobby has become quite affordable at the lower power end. The ~250mW analog rgb unit would be quite usable in a cheap small projector or lumia box despite having some limitations.

-David

Techhood correct? have had good dealings with the so far. got good PBS and IR filters from them- quick ship too.

How was the modulation on the analog unit? Were you able to get more than 7 colors? AKA is it really an analog driver on that unit. I'm still debating on if I want to get one of these or not. They are so cheap that I probably will even if it only last for a year or so before something burns out.

Same question here: how is the modulation on the analogue version? Would a quick fix with a 10K pot on the input leads do the trick?

I'm currently building a projector for someone at the moment. I'll try my best to assess the modulation later this week or this coming weekend.

any updates on the modulation?

Quote:

---

Originally Posted by macpod

I'm currently building a projector for someone at the moment. I'll try my best to assess the modulation later this week or this coming weekend.

---

I can confirm that on mine it is not true modulation but it is not TTL either. It is more like a PWM TTL. I can get different shades of color but when you look at them real close you can see that they are really just segments of each color. It is also nearly impossible to fade the colors in and out. Most of the time you end up with purple, as the green will turn off first. But don't get me wrong I still like what I paid to get this laser. It was perfect for my budget and completed my goal of having a laser projector to play with by the end of the summer. Once I get my Flexmods that should be coming in any day now I am going to remove the driver board the brick laser came with and add flexmods to get true modulation. This laser is not for everyone but I do not feel like I threw my money if the garbage by buying one.

Haven't had time to do testing. I agree with Salty in regards to if I am happy with what I paid for (I'm actually impressed the colors are aligned as well as they are.. I was expecting them to be the same if not worse than the TTL unit).

What do you all propose would be a good modulation test too?


And hey Salty, they never said it was Analog... it's analogo :D

dump the drivers and add new ones. all of a sudden....it modulates!