Pioneer 112 Results (red Hot)

[andyf97]

As far as i am aware, it could be pulsed using an analog switch and a timer that breaks the analog modulation fast enough to not be noticed.

The timer is free running that drives the enable of the anaolg switches gate.

Sounds pretty unsafe tho, if the timer stops the diode could get full power because you would infact be driving the diode upto its maximum current. I would not do it myself but its a thought as a way to gain some extra power from the diodes.

Anyone interested to try it?

[survey]

Carmangary is right, when we increment the frequency of pulses, shorter the time the laser is ON and so less Dimm.
Wich leads us to another point:
What happens if we have three laser diodes with a sequencer that gives a sequenced pulse with a width of 10ns to each one (by every pulse we inject to the sequencer, each laser would be ON for 10ns and OFF for 20ns).
All the three diodes will lase in a single pulse (10ns the first 10ns the second and 10ns the third). Now we increment the frequency to 3khz wich means that we can have each diode pulsing 1000 times for second.
Nobody's eyes can't see that flicker. The question is would that pulses be of such a magnitude (350 mw)? If so, your eyes would perceive 350mw X 3.
Damn I must study this carzy idea.

[drlava]

Carmangary is right, when we increment the frequency of pulses, shorter the time the laser is ON and so less Dimm.

You mean more dim? The duty cycle must still be observed, but at extremely short pulse times the risetime will start to have an effect.

Wich leads us to another point:
What happens if we have three laser diodes with a sequencer that gives a sequenced pulse with a width of 10ns to each one (by every pulse we inject to the sequencer, each laser would be ON for 10ns and OFF for 20ns).

With a sequencer you could have a near-continuous beam from 3 red (how will you do that, telescope?) lasers, however, because of the pulsing, each will be 1/3 of its 350mW peak brightness. In essence you will get a beam of the same apparent brightness if you summed 3 CW 115mW diodes.

All the three diodes will lase in a single pulse (10ns the first 10ns the second and 10ns the third). Now we increment the frequency to 3khz wich means that we can have each diode pulsing 1000 times for second.

You still must observe the maximum on-time at that current which may be 30ns (from above) in which case, by reducing the pulse frequency to 3KHz, you have decreased the duty cycle and average output power significantly. Not 350mW x 3.

Nobody's eyes can't see that flicker. The question is would that pulses be of such a magnitude (350 mw)? If so, your eyes would perceive 350mw X 3.
Damn I must study this carzy idea.

[andyf97]

Carmangary is right, when we increment the frequency of pulses, shorter the time the laser is ON and so less Dimm.
Wich leads us to another point:
What happens if we have three laser diodes with a sequencer that gives a sequenced pulse with a width of 10ns to each one (by every pulse we inject to the sequencer, each laser would be ON for 10ns and OFF for 20ns).
All the three diodes will lase in a single pulse (10ns the first 10ns the second and 10ns the third). Now we increment the frequency to 3khz wich means that we can have each diode pulsing 1000 times for second.
Nobody's eyes can't see that flicker. The question is would that pulses be of such a magnitude (350 mw)? If so, your eyes would perceive 350mw X 3.
Damn I must study this carzy idea.

Its certainly interesting to combine a few and cycle the on times.

Another thought I just had while drinking some tea. we crank up these diodes usually over there CW rating, maybe the 350mW can also be cranked up too but with the pulse durations instead of over power.

Oh just had a quote for these ML101J27-01 diodes $50 each based on 10 or more anyone have a better offer?.

[survey]

hi drlava yes you are right I mean more dim (less light). You see I'm Portuguese...errrr.
About the pulse power, if I'm not mistaken and acording the datasheet, a period or cycle with pulse width <30ns and duty cicle <35% will generate a high output power with 350mw.
it's not the min neither the max it's the CONDITION to have a pulse with 350mw of optical power output.

[kaz]

i can see logical thought behind the ideas but as soon as you introduce duty cycles and pulse width pulsing diodes for a high mean avarage power output is is not cost effective at all even if you had three diodes working in tandom to produce 350 mw why bother- the only thing that you might gain if you stay to the manufactures spec's is a longer lasting diode or diodes also it would be a pain to set up electrical wise as well, if i suck three of mine together i would have 750mw for a reasnoble amount of time theres always a trade off /my thoughts anyway

[dave]

Oh just had a quote for these ML101J27-01 diodes $50 each based on 10 or more anyone have a better offer?.

I just did a group buy for these. They were a lot cheaper than $50ea..

I might be tempted to do another group buy before long if there is some interest.

[andyf97]

Hi Dave,

at what cost and where from?

[kaz]

well i said i would post when it dies and here i am but at 424mw /700ma and 5.74 volts im not surprised for the full story check out the pioneer(free competition) results
Paul

[andy_con]

http://cgi.ebay.co.uk/ws/eBayISAPI.d...MEWA:IT&ih=009

these burners have open diodes that can be run at 300mw CW and they only get warm not hot.