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OEM and Focalprice Laser Goggles Review


HIMNL9

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^ Heheh, no, it was just cause if you was measuring your laser pointers in MegaWatt ..... well ..... please don't care about that guy that is stealing your 120 MegaWatt pointer, it's just me ..... :D

(no offense, ok ? just kidding :D)
 

bryce007

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I see what you're saying. But if the reading is off because the DMM is not calibrated with the resistors, then it would be consistently off when testing both goggles. Maybe I can get my hands on those shunt resistors somehow. Either way, I'll be doing the tests again when my Kenometer arrives. Thanks for the info!
 

lasersbee

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Hey bryce007....
like we talked about when I PMed you...

You bought the 120mW LPM module second hand from another member
that did not supply the User Instructions (which include the Optical
Correction Chart)...

He also did not supply the 3 included Resistors to test if you require the
On Board Shunt resistor for your type of DMM.

I gave you the URL to download the User Instructions and the Value of
the 3 resistors...

You don't need to Calibrate your meter...
just follow the instructions to Test your meter...

From the readings that I see here it seems that you need to connect the
2 Black wires together to shunt the input of your DMM with the on board
1meg shunt resistor...

In case no one knows... we Manufacture the 120mW LPM Module...
You can get more info here...

Calibrated Laser Power Meter Sensor Module by J.BAUER Electronics (EBAYHLPM)


As to the Testing of the goggles... the numbers are still good if used
as a reference of percentage difference...


Jerry
 
Last edited:

realista

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hello laserbee... so.. is ir true that the read number must be x 1.54 ? so... it it is displayed 100mw a laser.. it is real 154mw?

i think to understand right... or not? i have some confusion about it... i thought i need just connect the little lpm and see the results on the multimeter. now i listen that there are 3 resistor to choose to the meter someone can have.. and PLUS.. every readings must be x1.54. ...

what is the REAL power peak of bryce's laserpointer? 120mw or 120*1.54= 184?
 

lasersbee

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@realista....

It seems you did not understand anything that I said to you in PMs...
It seems that you did not understand anything that was written on our
website about the 120mW LPM Module and it seems you did not understand
what I posted above...

The 120mW LPM Module uses an OPTICAL SENSOR ...
Therefore it has different optical responses to different wavelengths...
We chose a 632.8nm HeNe laser as out calibration center (zero) point...

We supply an OPTICAL Correction Chart to correct the actual readings
when using lasers with wavelengths other than 632.8nm.

If it is too much trouble for you to multiply 2 numbers together... then this
LPM would be much better for you.. you just shine a laser on the Thermopile
and read the mW on the LCD screen... (no Correction Chart Required)..

Calibrated 1 Watt Laser Power Meter + Thermopile Sensor by J.BAUER Electronics (EBY1WLPM)

AGAIN... The 3 resistor that we supply are only to test what type of DMM
you own... They can be discarded after the test...
All is explained in the User Instructions which come with the 120mW LPM
Module we supply...

I don't know what the real power of bryce007's lasers are because I don't
know if he tested his DMM or used the correction chart...

AGAIN...He stated that he did not receive any instructions when he bought it
used from another member...

And I don't have his Laser in my hands to test it here in the shop...


Jerry
 

jwc

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Nice writeup, bryce007. I'm interested to see the test results from your Kenometer. The power difference between testing with and without goggles doesn't seem nearly large enough. I had done some brief testing with my Liconix LPM (with photoelectric detector) and saw that a 150mW green laser dropped down to less than 1mW; I bought a pair of goggles from Things.

When you get the Kenometer, you'll probably need an IR filter to get accurate measurements on the quality of the goggles.
 

HIMNL9

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jwc, careful that some optical sensors read correctly only from 400 to 700 nm, and drop sensitivity out from this range ..... so, if there's a good amount of 808nm, some of them can't read it correctly, or not read it at all.

But there's an easy way for see this, and is get some of these BPW photodiodes made specially for IR receivers ..... the ones with "black" plastic case, usually the "black" plastic is in fact a pass-IR, block-visible filter material, so can read the IR content with one of them (but use a diffuser, not shot the beam directly on them, cause otherwise you risk to melt the case :p).
 




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