New Budget Laser Power Meter in the Works - Future GB material. 1-800mW

[dr_lava]

After looking around at some of the laser power meters out there -

The Sper scientific pocket laser meter costs $190, has a 40mW range, and a hand-calculator is necessary for wavelength adjustments, as the display is only calibrated for 1 wavelength.

The coherent lasercheck costs $300-400, range 1-1000mW, and wavelength is entered for automatic reading adjustment.

Ted_park mentioned an Andover Holography unit that was made for holography primarily, but could work.

I have been talking with 'Andover holography' about tuning this unit for our purposes. So far, this is a preliminary spec:

· Autoranging measurement of light power in 4 ranges from ~100 uW to 100mW
· At least 5% accuracy over native range
· Range extends to 800mW with filter in 'ND8' mode (calibrated)
· Multiple sensor calibrations available for different wavelengths :488,532,635,660, selectable in a menu.
· 16 character by 2 line alphanumeric display
· 3 Pushbuttons provide control of measurements & configuration using a simple menu system.
· Automatic 5-minute power down to extend battery life
· RS232 datalogging
· Peak hold remembers the peak reading in a series
· 2Hz (2 samples/sec) update and logging rate, 400Hz internal sample rate


Available via a group buy soon at less than the Sper Scientific cost.

Here's a pic of the holography meter. it has an external sensor. The laser power meter version will have a built-in sensor like the lasercheck, and no backlight.

What do you think?
Would you be interested in a unit like this?

 

[SenKat]

Bring it on, man ! Count me in on that sucker !

 

[ted_park]

I have one of the holography units, and it works well. I don't typically use it for green laser power measurement, but the results I have got are consistent with the sper meter.

The stock unit reads for 532 and 633 nm, so that should cover green laser enthusiasts. Perhaps it might be nice if sensors that could read >100mw are available - the standard unit reads to 100mw, which is enough for the holography work that I do. I think the meters I have already should be enough though.

--Ted.

 

[shawndoe]

Hi,

Sounds like an affordable unit and I really like the logging option. I could be interested depending on how much they want for it.

Have a good one.
Shawndoe

 

[zigziggityzoo]

Yeah, sounds awesome. It does depend on the price for me... after all, my hobby(habit?) has a budget!

 

[dr_lava]

The estimated unit price for a 10-unit group-buy is $150/unit. First come, first served.

 

[Hemlock Mike]

Dr_Lava --


I'm in for $150.00 Let me know when to send $.
I still have your address from the diodes GB.

Mike

 

[PhotonWrangler]

The estimated unit price for a 10-unit group-buy is $150/unit. First come, first served.

This looks interesting to me also. I'm in for a group buy.

 

[RVRM]

in

 

[LED123]

Interested in one. Does it come with the filter for the 800mw measurement.

 

[dr_lava]

Yes it does.

The purpose of this thread was to solicit feedback and comments on the design, not really to start a group buy (that belongs in the GB area) If you want to get in line this early, please PM me only. thank you.

 

[dr_lava]

Updated the spec to include sample rate.

 

[Kiessling]

The purpose of this thread was to solicit feedback and comments on the design, not really to start a group buy (that belongs in the GB area) If you want to get in line this early, please PM me only. thank you.

Good call.
Please discuss the design only and wait for the gb to actually start (in the gb forum then). A link pointing there in this thread would be a good idea then
Thanx.
bernhard

 

[jkaiser3000]

probably include a calibration function so it could be used with other wavelengths (405nm, 780nm, etc.)

 

[dr_lava]

probably include a calibration function so it could be used with other wavelengths (405nm, 780nm, etc.)

I've talked with the designer about exactly that and he feels that it could cause corruption in the other cal values to enable eeprom writes to add new values - if there were to be power glitches while inserting and removing the batteries.


This being the case he has said he will do updates and re-cals for free, just mail the unit to him.


If this is a big issue to you or anyone considering buying the unit, please let me know and I will push the issue (cause I'd like to see it, too).

 

[Hemlock Mike]

I think for a ~ $150 unit, we can't expect too much. That would be a nice feature however but would require the user to have several known units to establish a power curve.


Mike

 

[Hemlock Mike]

Dr_Lava-

What's the OD of the cases you are sending ?? I'm on my lathe tonight !!! I'll get it close.

Mike

 

[jkaiser3000]

Regarding the calibration curve, I was actually thinking about taking a realtive reading from an already available wavelength. Say you want to measure 405 nm, make the reading at the 532nm setting and then apply a relationship to get the true output at 405 (like 405nm is half 532nm output reading). Sort of like that.

However, I only propose it because of the niftinness, but I could live without that feature. After all, 405nm is not very common yet. On the other hand, 780nm and 808nm are quite common.

Oh well, guess we can't win'em all

 

[Ragnarok]

Yes, if we knew the sensitivity curve of the sensor, measurements of "in-between" wavelengths could at least be interpolated with a fair degree of accuracy. If the units are only capable of a limited number of values "built in", could/would they supply a written list of multipliers for different wavelengths?

I guess that depends on the unit-to-unit consistency of the detector, though.

I would be interested in purchasing one of these meters if the project moves forward.

 

[The_LED_Museum]

The Sper Scientific has wavelength multipliers printed on the inside of its lid; to wit:

I have not found this to be a pain in the toliet muscle at all; as long as you have ready access to a calculator (Windows has one built-in), it is easy.