robinlawrie
New member
- Joined
- Mar 1, 2023
- Messages
- 14
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- 1
apologies if this has been covered, ive had a browse but not found much beyond "its better to get an analog version in the first place"
ive got a (very) cheap 500mw rgb projector, and the 7 color limit is a bit annoying having seen the effect analog control gives. i would also like to improve the alignment of the module which would be easier with dimmed output.
im a bit of a total noob wrt laser drivers so please be gentle
so my options seem to be
a) modify existing drivers to provide analog modulation.. this seems to be "not recommended"/more complex than im imagining from what i have read.
as far as i can see, given there are pots on the driver to tweak output for the 3 diodes, this sets an upper current limit. some kind of modification here could retain that limit but enable a transistor/mosfet in series (or parallel, depending if i need to increase or decrease resistance) to vary the output..
happy tobe educated as to why this wont work
b) add some kind of post-driver circuit.. maybe using a mosfet to variably "short" the diode through a sufficiently meaty resistor. this would keep the driver applying the correct current, but allow what arrives at the diode to be varied.
c) replace the driver board.. i could measure the current/voltage provided to each diode and set a new driver to match for each one.. something like the optlasers analogue modulated one looks good, but the price seems very high for such a simple weeny circuit, considering id need 3 of them... im sure they are quality kit and maybe made locally, which is to be respected, but in my case, it would cost more than the whole setup currently does.
maybe someone could suggest a cheaper alternative that could work without killing the diodes in a week (assuming they last that long anyway!)
obviously there is still the issue of whether the control board will actually pass analogue signals to an analogue driver from ilda, but thats for another discussion.
thanks!
ive got a (very) cheap 500mw rgb projector, and the 7 color limit is a bit annoying having seen the effect analog control gives. i would also like to improve the alignment of the module which would be easier with dimmed output.
im a bit of a total noob wrt laser drivers so please be gentle
so my options seem to be
a) modify existing drivers to provide analog modulation.. this seems to be "not recommended"/more complex than im imagining from what i have read.
as far as i can see, given there are pots on the driver to tweak output for the 3 diodes, this sets an upper current limit. some kind of modification here could retain that limit but enable a transistor/mosfet in series (or parallel, depending if i need to increase or decrease resistance) to vary the output..
happy tobe educated as to why this wont work
b) add some kind of post-driver circuit.. maybe using a mosfet to variably "short" the diode through a sufficiently meaty resistor. this would keep the driver applying the correct current, but allow what arrives at the diode to be varied.
c) replace the driver board.. i could measure the current/voltage provided to each diode and set a new driver to match for each one.. something like the optlasers analogue modulated one looks good, but the price seems very high for such a simple weeny circuit, considering id need 3 of them... im sure they are quality kit and maybe made locally, which is to be respected, but in my case, it would cost more than the whole setup currently does.
maybe someone could suggest a cheaper alternative that could work without killing the diodes in a week (assuming they last that long anyway!)
obviously there is still the issue of whether the control board will actually pass analogue signals to an analogue driver from ilda, but thats for another discussion.
thanks!
