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Modifying a store bought laser projector

override

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For christmas my girlfriend bought me a mini laser projector which has gotten me back into the hobby a bit.

I already spliced the speaker wire to a female headphone jack to get decent sound out it when synced, but I'd really like to swap the green diode to a violet and that project is a bit over my head.

I have a 5mw violet pointer that I don't mind sourcing from if it'll work, but besides buying premade pointers (best one I've got is a 1w blue spartan) and working with general electronics (circuits, soldering etc) I don't have much experience here.

From my very basic research so far I think I'll have to swap both the diode and the driver, but the driver may not work since the pointer ran on 2x AAA's and the projector runs on AC power, although I suspect it converts it to DC before actually getting to the driver.

Anyway, I'm looking to be pointed in the right direction for general build information, I'm not so much looking to just modify this unit as I am learn all I can about building them.

What are some of the better resources out there?

Thanks in advance!
 



lasersbee

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From your explanations of what you want to do
and your stated experience in electronics... the
easiest and least expensive (in the long run) thing
to do is let someone with basic electronics building
experience do the project.
Trying to modify a car to go faster without basic
Automotive skills becomes very expensive very fast.

Jerry
 

Grix

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Even if the driver in your pointer works on the same DC voltage as the driver for the laser module in the projector, you probably want to get a different one. Because laser modules in projectors need a blanking modulation signal, otherwise they will just be on the entire time even when jumping from one lit segment to another. You can get cheap driver with TTL modulation on ebay etc (quality will be bad though), here for example: http://www.ebay.com/itm/272468374286
TTL means it supports either on/off blanking, which is likely what the existing laser module in your projector has. The alternative is analog modulation, which supports any arbitrary brightness intensity between off and on.
 
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override

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Trying to modify a car to go faster without basic
Automotive skills becomes very expensive very fast.

Jerry
Funny you mention cars, my first car was a $35 Escort wagon with a burnt out clutch. I armed myself with a chilton manual and a set of craftsman tools not knowing even how to change the oil and had the transmission out in a couple days. It took longer to put back together, but it drove again, and that was 15 years ago. Now I've got a small collection of fast shit. What do you ride?

Even if the driver in your pointer works on the same DC voltage as the driver for the laser module in the projector, you probably want to get a different one. Because laser modules in projectors need a blanking modulation signal, otherwise they will just be on the entire time even when jumping from one lit segment to another. You can get cheap driver with TTL modulation on ebay etc (quality will be bad though), here for example: Electronic 12V TTL Step-down Laser Diode LD Power Supply Driver Board Stage New | eBay
TTL means it supports either on/off blanking, which is likely what the existing laser module in your projector has. The alternative is analog modulation, which supports any arbitrary brightness intensity between off and on.
So I've cracked open the case for a second time now, (the first was just to see if the swap was intimidating or the diode was too integrated) and it seems the driver is integrated with the main control board.

Your post got me researching drivers a bit more, is it true to say that all the driver does is regulate and modulate voltage output to the diode?

Since im stuck with the stock driver, my hopes of using the violet diode I have are diminished, since I doubt they operate on the same voltage. I figure I can find the operating voltage by probing the wires with a volt meter, then simply find a violet diode that operates on the same. The green diode that I want to swap is the one with the heatsink so I should have plenty of room and alignment is my only other problem.

Do you guys see any errors in my process? Anything else I should address before i start probing and cutting? Or am I way off base and underestiming the simplicity of this whole thing?

Thanks again!
 
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diachi

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Funny you mention cars, my first car was a $35 Escort wagon with a burnt out clutch. I armed myself with a chilton manual and a set of craftsman tools not knowing even how to change the oil and had the transmission out in a couple days. It took longer to put back together, but it drove again, and that was 15 years ago. Now I've got a small collection of fast shit. What do you ride?



So I've cracked open the case for a second time now, (the first was just to see if the swap was intimidating or the diode was too integrated) and it seems the driver is integrated with the main control board.

Your post got me researching drivers a bit more, is it true to say that all the driver does is regulate and modulate voltage output to the diode?

They regulate/modulate current as laser diodes are current devices, but yes, basically.


Since im stuck with the stock driver, my hopes of using the violet diode I have are diminished, since I doubt they operate on the same voltage. I figure I can find the operating voltage by probing the wires with a volt meter, then simply find a violet diode that operates on the same. The green diode that I want to swap is the one with the heatsink so I should have plenty of room and alignment is my only other problem.

You won't, all violet diodes operate at similar voltages, around 5-6V IIRC. Green, assuming it's DPSS (532nm) will be around 1.8V. Seeing as the drivers should be current regulators, it might work, assuming the driver is capable of output at 5-6V and is set at the correct current.

Do you guys see any errors in my process? Anything else I should address before i start probing and cutting? Or am I way off base and underestiming the simplicity of this whole thing?

Thanks again!

See replies in red.
 

lasersbee

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Funny you mention cars, my first car was a $35 Escort wagon with a burnt out clutch. I armed myself with a chilton manual and a set of craftsman tools not knowing even how to change the oil and had the transmission out in a couple days. It took longer to put back together, but it drove again, and that was 15 years ago. Now I've got a small collection of fast shit. What do you ride?
I have a Van to haul my R/C vehicles to the flying field
and a Harley to keep me sane...:beer:

Use the same technique to get you up to speed for some
basic Electronic knowledge (Google) and I'm sure you can
modify your projector yourself.

Jerry
 




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