Pulsed Laser Driver

[FrostyTheDadMan]

sorry, i cant agree to that.
it cant burn the same, since the average power of the pulsed laser is less than 200mw. 200mw is peak with the pulsed one. if the dutycycle is 50%, the effective, average power is 100mw (given the pulsing is fast enough, which is definitely so with 1MHz).
it wont look the same bright neither. the receptors in your eye integrate the incoming light with about 25hz. the absolute count of photons is the only thing that counts for brightness and visibility (with a given wavelength). so it doesnt matter if you shoot one million photons into your eye in a millisecond or a microsecond. the flash will both times look equally bright.

i hope i didnt misunderstand you. if you meant "200mw average" when you said "1Mhz [..] and out putting 200 mW", I completely agree to you!

manuel

As has been stated, brightness wise, you will perseve the brightness as the average power. Thus if you have a pulsed laser that was 1W QCW and one that was 1W CW, they would be equally bright.

Correct. Average power is what matters for percieved brightness and electrical tape burning abilities. PHRs and the other LDs we typically play with, even if driven at optimum pulsed conditions, will not deliver a higher average power than when driven CW. Nor will they have a significantly longer life. Some people here seem to not understand the difference between peak power and average power.

I agree that we disagree
Try to run a phr at 209 mA for 5 minuets with a CW driver, Heck try it at 170 mA (It will fry)
I have ran a phr at 209 mA for 58 minuets with the MMD pulse drive and it still lives in fact I am planning a time test to see just how long it will last.
I have had phr's that ran at 244 mA PW and it looked as bright as my 6X :drool:

 

[Laser_Ben]

Right, and your average power on the second test is lower then the average power on the CW test.

 

[FrostyTheDadMan]

Right, and your average power on the second test is lower then the average power on the CW test.

Have you even tried to run a phr at 170 mA to 200mA CW yet?

I am in the process of running the same phr at 206 mA PW for a little more then 4 and a half hours now and its still going strong.
I will keep it going until the diode dies or until midnight which will be an 9 hour run and tomorrow I will start the test again and I will repeat the test until the phr dies.

Now why do you think the data sheets give you a CW power rating and a PW power rating? It does not say peak or average power, does it.

Because it takes more power to burn the data on a disk then to read the data on the disk. the higher the power the faster the write speed

I mean use some common sense, come on.

 

[maxh]

Common sense says:
100 mw at 100% duty cycle (i.e. CW operation at max spec) is significantly more power and visibility than 180 mw at 40% duty cycle (i.e. pulsed operation at max spec.) Data sheets have to do with a components actual characteristics and limits, and are independent of the end user's application.

 

[FrostyTheDadMan]

Common sense says:
100 mw at 100% duty cycle (i.e. CW operation at max spec) is significantly more power and visibility than 180 mw at 40% duty cycle (i.e. pulsed operation at max spec.) Data sheets have to do with a components actual characteristics and limits, and are independent of the end user's application.

thats why the MMD has been designed to meet the average data sheets
And its a 50% duty cycle not a 40% duty cycle

lets look at voltage say you have 100 volts DC pulsed at 50Mhz with a 50% Duty Cycle, now you hook up your multimeter to it. will your multimeter read 50 volts? no it wont, it will read 100 volts. Energy is ether their or it is not their is no average. if that was the case then when you test your outlets in your house it would read 60 volts instead of 120 volts. energy never stops it only changes form

now the peak power, that occurs when the load is turned on so if you have 50,000,000 on times per second that means you will have 50,000,000 peak power points per second but then its no longer peak power it is now pulsed power because of the repetition.
This is all common sense

 

[Krutz]

well, since we're at examples anyway:

1) a waterstream with 100l/s. cw, constant flow

2) a pulsed waterstream with 180l/s peak, dutycycle 50%. thats one second 180l, one second nada. of course the timedivision-"steps" dont matter, the duty is the only thing that counts, besides peakpower.

which one has higher peak-flow? the second. which one will produce more energy when used with a watermill? the first.

manuel

 

[FrostyTheDadMan]

Well lets just be a little more intelligent, were talking energy not water volume.
Electricity is energy, laser power is energy, water power can be a form of energy, so I will play your little game.
if your constant 100 psi of water was turning a generator turbine and my pulsed 180 psi at a repetitive 50,000,000 times a second was turning another Identical generator turbine my generator would be generating almost twice the power then yours.
because their is almost twice the power pushing mine as yours. :lasergun:
so did it take you all day to think up that? manuel what are you 12?¿
Keep talking maybe some day you will say something intelligent
Grow Up!!!!!
I refuse to have a battle of the wits with an unarmed person!

 

[maxh]

Well lets just be a little more intelligent, were talking energy not water volume.
Electricity is energy, laser power is energy, water power can be a form of energy, so I will play your little game.
if your constant 100 psi of water was turning a generator turbine and my pulsed 180 psi at a repetitive 50,000,000 times a second was turning another Identical generator turbine my generator would be generating almost twice the power then yours.
because their is almost twice the power pushing mine as yours. :lasergun:
so did it take you all day to think up that? manuel what are you 12?¿
Keep talking maybe some day you will say something intelligent
Grow Up!!!!!
I refuse to have a battle of the wits with an unarmed person!

Actually Manuel's analogy was spot on. It was so clear and concise that even someone with the mentality of a 12 year old could get it. I wasn't going to get personal, but after your attacks on him, I'll voice my opinion.

I think you've shown people who you are and what you know here in this thread (besides confusing flow rate and pressure, you don't fully understand energy and power), and especially that fake 150mw nichia thread where you tried to school a member on laser diode manufacturing when he knows about 10,000 times more about the subject than you.

One of the only reasons I've continued to reply to this thread is that I've been wondering if you were scheming to release some grand, new pulsed driver that could turn a phr into an 8x, and try to pump money out of the less educated noobs that've just joined and haven't had time to learn better. I wanted to make sure reason and rationality were present so the unknowledgable would have a chance to make an informed decision should you start trying to market such a magical driver. A lot of what you've said in this thread sounds like jargon filled sales hype, like what you sometimes get out of a marketing department, making the engineering department cringe and shake their heads.

And I don't believe for one second your claims about what you've been driving phr's at. Unless perhaps you're improperly measuring or calculating the values you state...

 

[hydrogenman15]

Well lets just be a little more intelligent, were talking energy not water volume.
Electricity is energy, laser power is energy, water power can be a form of energy, so I will play your little game.
if your constant 100 psi of water was turning a generator turbine and my pulsed 180 psi at a repetitive 50,000,000 times a second was turning another Identical generator turbine my generator would be generating almost twice the power then yours.
because their is almost twice the power pushing mine as yours. :lasergun:
so did it take you all day to think up that? manuel what are you 12?¿
Keep talking maybe some day you will say something intelligent
Grow Up!!!!!
I refuse to have a battle of the wits with an unarmed person!

If your running a diode at 50% duty cycle at
200mA's for an hour and another at 100mA's at 100% for an hour. Also, lets say both are running at 6v's. So diode #1 clocked in at 30min's of actually being on and diode number 2 clocks in at 60min's of being on.

.200 x 6 =1.2 watt's and it was running for 1/2 an hour which means .6 watt hours of energy.

Diode #2: .100 x 6 = .6 watt's. .6 watt's for 1 full hour is .6 watt hours
of energy. So there both taking the same amount of energy but one is taking more energy at a time and is putting out more energy at a time.

--Hydro15

 

[HIMNL9]

Uhm, please don't start a cypher war, ok ? ..... all knows that power is the same, when 100 at 100% duty cycle, 200 at 50% duty cycle, 400 at 25% duty cycle, and so on, it's just a physic law.

But, the OP opened this post about BEAM VISIBILITY, that is a different thing ..... and, worse, it's a SUBJECTIVE thing, that depend from a lot of factors, not just output power, but overall individual eye sensitivity, to colors and intensity, eye accomodation, also stress (long time in a high light environment, long time in front of a monitor, long time working with little details at short distance, and so on).

IMHO, the only way for check this, is using 2 identical diodes (PHR, as example, that they now cost almost nothing, or reds) in identical hosts and lens, focused at the same spot diameter, one fixed with a linear driver, as reference beam, and one drived with a pulsed (PWM, PCM, whatever you prefer) driver, and look at them for personal impressions, reporting them honestly ..... unfortunately, due to the highly subjective differences in sensibility and interpretation, there is no way for calculate this thing with only mathematic and formulas

 

[millirad]

^ I would like to see that experiment! Then Niko gets the answer to his original question.

 

[FrostyTheDadMan]

Uhm, please don't start a cypher war, ok ? ..... all knows that power is the same, when 100 at 100% duty cycle, 200 at 50% duty cycle, 400 at 25% duty cycle, and so on, it's just a physic law.



IMHO, the only way for check this, is using 2 identical diodes (PHR, as example, that they now cost almost nothing, or reds) in identical hosts and lens, focused at the same spot diameter, one fixed with a linear driver, as reference beam, and one drived with a pulsed (PWM, PCM, whatever you prefer) driver, and look at them for personal impressions, reporting them honestly ..... unfortunately, due to the highly subjective differences in sensibility and interpretation, there is no way for calculate this thing with only mathematic and formulas

I am not trying to start any thing, OOO I am scared, not. I already stated I agree we disagree, to most of you that enough, But that was not enough for him, he keeps at it like a child arguing with a sibling! and wont stop! Water is a liquid, Laser is radioactive Light. you cant touch it, it touches you.
I have other things to do other then argue, Like further my research in clean coal tec and alt fuels.
By the way just for you all I pushed that Phr to its max It ran for about 30 seconds @ an Insane 356 mA then that poor little guy died.
When Dave sends back the MMD he was to test I want to send it to the person that started this thread because seeing is believing. then you all can argue with some one else.

And Just for you people I will call my Friend Stephen Knapp @ Coherent Lasers who in fact has generously donated 5, 1000 dollar LBO crystals to my research in clean coal tec along Sanyo and Sony and to many to name all of them. and see what he says about your friends analogy :crackup:
If you all want to discuss this like adults come over to LE Forum and we will discuss it in depth.

 

[FrostyTheDadMan]

Actually Manuel's analogy was spot on. It was so clear and concise that even someone with the mentality of a 12 year old could get it. I wasn't going to get personal, but after your attacks on him, I'll voice my opinion.

I think you've shown people who you are and what you know here in this thread (besides confusing flow rate and pressure, you don't fully understand energy and power), and especially that fake 150mw nichia thread where you tried to school a member on laser diode manufacturing when he knows about 10,000 times more about the subject than you.

One of the only reasons I've continued to reply to this thread is that I've been wondering if you were scheming to release some grand, new pulsed driver that could turn a phr into an 8x, and try to pump money out of the less educated noobs that've just joined and haven't had time to learn better. I wanted to make sure reason and rationality were present so the unknowledgable would have a chance to make an informed decision should you start trying to market such a magical driver. A lot of what you've said in this thread sounds like jargon filled sales hype, like what you sometimes get out of a marketing department, making the engineering department cringe and shake their heads.

And I don't believe for one second your claims about what you've been driving phr's at. Unless perhaps you're improperly measuring or calculating the values you state...

I did not even know this thread was here until LaserBee informed me.
also I did not start this thread nor have I asked any one for a dime have I? so your clam of me scamming money from any one is false and why would I have LaserBee test one of my drivers along with Dan and K-9 if it was a scam? I am also buying them Phr sleds for testing the drives, then you can see what they say. all the money has come out of my pocket! Paten's are not cheep! about 5,000.00 USD
And as far as not knowing anything about Laser diode production Well you can contact him your self. this man has Informed me that I am working with cutting edge Laser technology!!!!
Stephen L. Knapp
Field Sales Engineer
Midwest Office
Coherent, Inc.
(847) 433-9163 Office
steve.knapp@coherent.com
And nikokapo my offer is still open if you want one let me know.
Last, the only place any one will be able to buy these when their ready will be at laser surplus parts

 

[Krutz]

I refuse to have a battle of the wits with an unarmed person!

Water is a liquid, Laser is radioactive Light. you cant touch it, it touches you.

I have other things to do other then argue, Like further my research in clean coal tec and alt fuels.

thank you a lot for clearing this whole topic, frosty. for a moment i was mistakenly supposing you would have the means (knowledge in hf-circuits, lasertechnology, neurobiology and basic physical laws) to build such a driver. thats why i tried to keep you from a possibly time- and moneyconsuming failure. but now, with your generous help, i know what to expect from you. well, everyone may see my age in my profile. how about yours? *smirk*

interestingly, i have a friend who talks exactly the same way all the time. he's up to revolutionary protection-bikecloth, solving the world energy problem with more effective genious machinery in the sahara, building a totally new micropayment-system over gprs-technology, well, and so on.. he is short-tempered too actually.

well, thanks again for an amusing morning, frosty! *smiles*


manuel

 

[FrostyTheDadMan]

thank you a lot for clearing this whole topic, frosty. for a moment i was mistakenly supposing you would have the means (knowledge in hf-circuits, lasertechnology, neurobiology and basic physical laws) to build such a driver. thats why i tried to keep you from a possibly time- and moneyconsuming failure. but now, with your generous help, i know what to expect from you. well, everyone may see my age in my profile. how about yours? *smirk*

interestingly, i have a friend who talks exactly the same way all the time. he's up to revolutionary protection-bikecloth, solving the world energy problem with more effective genious machinery in the sahara, building a totally new micropayment-system over gprs-technology, well, and so on.. he is short-tempered too actually.

well, thanks again for an amusing morning, frosty! *smiles*


manuel

You know I was a little hard on you and I had that coming from you for the those few comments, I was out of line with you.
I Apologize to you
but what you need to understand is that I posted over and over 50% duty cycle and a high pulse rate and you kept changing the cycle to less then 50% and pulse rate way to slow, so that does pad thing in your favor. its not fair to change the facts.

Yes I am working on things to help every one. Like Our Ozone is mainly made up of Trioxygen molecules so the emission we produce needs to mimic the trioxygen and that can be achieved by polarizing the emission molecules and free air properly and with the proper nm of Laser radiation then its no longer emissions its what I call Emoxygen. I would love to post the hole thing but that would consist of a 20 page report.

Now how would like to fill your cars fuel tank from your garden hose?
we are in the process of preparing for the final Patent

 

[Krutz]

no offence taken, thank you!

well, i think several people are talking about different things here. i am solely talking about (average) power, while others (you included) talk about visibility. well, i would suggest to try it with two red diodes (the wavelength-differences arent that big and noticeable) and simply check which laser, the cw or pulsed one, *seems* brighter. i guess they will look the same (when average power is same), from what i know about how the eye works, but here its not much more than guesses from my side.

and hey, if its working, i'm the last one who wouldnt use it just because i was proved wrong ;-)

cheers,

manuel