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Introducing Radiant Electronics and the Radiant Alpha Power Meter

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Am I smoking crack or did mario say his LPM is $99?
 

lazeerer

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Am I smoking crack or did mario say his LPM is $99?

Mo Thats exactly what i said $100 bucks. Its such a low price that i am tempted to by one myself even tho i have a LPM already .:p

Never mind now. That $0.95 just broke the deal. I'm walking away.....
^^:crackup: Too Funny. I need that today.
 
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paulzimm

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Product is out of stock? When will you have more? I want to purchase once I see a review on how accurate it is...
 
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I am also interested in one of these. The website still showing out of stock..
When will they be available for order?

Its not mentioned, so im assuming not... Does this meter have
any sort of data logging feature? Not necessary but a definite plus.

Also a few questions which I dont think have been already asked...

-What is the lowest power that can me measured accurately?
-What is the accuracy of the meter across the range?
-What is the wavelength range of the sensor coating?
-How much current does the LPM pull from the 9Volt battery?
-Does the display come in any other color than green?

Look forward to trying one out

:beer:
 

MarioMaster

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Thanks everyone for the kind words, also for those who ordered from the first batch of meters - they will ship tomorrow.



I am also interested in one of these. The website still showing out of stock..
When will they be available for order?

Its not mentioned, so im assuming not... Does this meter have
any sort of data logging feature? Not necessary but a definite plus.

Also a few questions which I dont think have been already asked...

-What is the lowest power that can me measured accurately?
-What is the accuracy of the meter across the range?
-What is the wavelength range of the sensor coating?
-How much current does the LPM pull from the 9Volt battery?
-Does the display come in any other color than green?

Look forward to trying one out

:beer:

These meters will measure lasers down to 1mW, however the margin of error increases at low power since there's a big percent difference between 2mW and 3mW, versus say 1002mW and 1003mW. Expect about 5% variation at full scale, as I don't have an NIST calibrated meter to reference them to, only my factory-calibrated Ophir thermopiles.

The sensors are broadband coated, they should have no problems reading lasers from 300-1000nm, however beyond that range I am unable to test.

The meter draws from 100-250mA depending on the input voltage. This is definitely the worst part about the meter, the battery life won't be great but there isn't too much I could do about it at this price point. I will however be selling an AC adapter for those who don't need their meter to be portable.

The displays can also come in other colors or LCD with a blue backlight, but this will be $5.99 extra and add 1-2 weeks to your order. It can be noted that the green LED display CAN be seen clearly even when wearing laser goggles for green lasers.

These units to not have a data logging feature, but it is currently in development (no ETA at this time)



Also, the initial stock is gone but I am in the process of making more meters. I will update this thread when new stock is available.
 
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I can live with the green screen, makes sense with the goggle thing..

Please put me down for the next available unit, ill put some $$$ aside
in my paypal.

I will keep an eye on this thread or if you want, PM me when you have
one ready....




Thanks everyone for the kind words, also for those who ordered from the first batch of meters - they will ship tomorrow.






These meters will measure lasers down to 1mW, however the margin of error increases at low power since there's a big percent difference between 2mW and 3mW, versus say 1002mW and 1003mW. Expect about 5% variation at full scale, as I don't have an NIST calibrated meter to reference them to, only my factory-calibrated Ophir thermopiles.

The sensors are broadband coated, they should have no problems reading lasers from 300-1000nm, however beyond that range I am unable to test.

The meter draws from 100-250mA depending on the input voltage. This is definitely the worst part about the meter, the battery life won't be great but there isn't too much I could do about it at this price point. I will however be selling an AC adapter for those who don't need their meter to be portable.

The displays can also come in LCD with a blue backlight, but this will add 1-2 weeks to your order. It can be noted that the green LED display CAN be seen clearly even when wearing laser goggles for green lasers.

These units to not have a data logging feature, but it is currently in development (no ETA at this time)



Also, the initial stock is gone but I am in the process of making more meters. I will update this thread when new stock is available.
 

Benm

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what's there to look for in a meter other than accuracy? build quality?
Things like response time, and readout consistence regardless of where you point a laser onto the sensor, or even when aiming from a slight angle. Build quality/durability would also be important, and maintenance of calibration over time.

For $100 it seems like a very good deal, though the 2 watt upper limit seems something that would become problematic pretty soon. It would be nice to have an accurate 50% or 75% reducing ND filter with this. At this price level i'd seriously consider getting one if reviews are positive.

And as far as the TEC-on-a-heatsink issue goes: its one of the few ways to construct a thermal LPM. I suppose its very cost effective if the minimum readout isn't a big issue - i doubt these would sense the heat of your hand in front of the sensor like the disc-type thermopiles do... but few people actually need that, most hobby laser constructions would be in the 5 to 5000 mW range nowadays.
 

MarioMaster

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Since TECs have higher thermal mass than a radial thermopile like the Ophirs, their response time is significantly higher - this is evident if you have ever compared a laserbee to meter with a radial thermopile. That doesn't mean that they aren't sensitive though ;)

These meters will easily detect the head from your hand given a few seconds to respond.


I plan on releasing higher power versions in the future also, you can expect a 10W model not too far in the future. Need to take care of the initial market saturation first.
 
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Benm

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A 10W model would be cool, or even a 5 watt one. The problem is that nowadays 2 casio diodes pbs-combined would exceed that 2 watt mark. I think the durability of the coating needs some work too... 37W/cm2 is not that much, considerig it equates to 370 mW/cm2 - a value easily achieved by the A140 diodes due to their stripe output pattern.
 

MarioMaster

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Damage testing was done with a 445nm laser, unless it's focused it will not damage the sensor. The 37W threshold is a conservative value. I'm open to ideas if you can find a better coating :)
 
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Benm

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Conservative or not, i'm just saying that it could easily be exceeded by a 445 focussed to infinity. Close to the laser the pattern is a rather fine line a few mm wide. Perhaps thermal conduction allows this heat to spead a little across the sensors surface so it averages out below the actual damage threshold?

Also, i just read back on the current consumption: 200 mA or so is quite a lot of current... but doesnt most of it actually go into the LED readout display? If that is the case it would be better to drive te display at lower current/brightness or replace it with an LCD with a high effiency backlight.

Perhaps you could consider using a high-effiency red display: those are often much more visible for a given current than green led displays, and arent expensive either ($2 or so for a 4-digit model).
 

lasersbee

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Damage testing was done with a 445nm laser, unless it's focused it will not damage the sensor. The 37W threshold is a conservative value. I'm open to ideas if you can find a better coating :)
There was a Thread on PL a while back that discussed
a formula that could be used as a coating...
I'll see if I can hunt it down for you and post the link here..

BTW... when will you get more of these in stock...
I might perhaps want to get one for some testing...
Did you only have the 5 for sale...:thinking:

Jerry
 
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WLHostage

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I'm definately interested in a $100 LPM as well once we get some data on it. Been looking at laserbee's, but $300 is a lot for something that is rarely going to be used.
 
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