Laser Power Measurement Devices....overview !

[SenKat_Stonetek]

Updated my post pertaining to my plethora of power meters {perfectly poetic alliteration, eh ? }

 

[jimc1128]

I received my Viasho Laser Power Meter (VLP-2000) about a week or so ago.  It is a nice and simple meter to use.  Jack, at Optotronics, has checked it out and measured it against the Coherent LaserCheck and the Fieldmaster GS laser power meters with very consistent results.
 
Characteristics[ch65306]
Wide spectrum response range
Small size detector
Simple operation ,digital display  

 
Specifications:  

Applicability - CW laser
Spectrum response range - 200nm ~ 2500nm
Measurement range - 0~ 2W  
Sensitive area of detector - [ch934]10mm
Max permitted power density - 200W
Measurement error  - <±5%
Display precision  - 4 and 1/2 bits
Input voltage - AC 80~260V 50Hz
Power consumption - <10W

The thermal head is really nice, it has a sturdy stainless steel
mounting and the head has a set screw to adjust the height up and
down.

 

[acro-ii]

I have 2 LPM's:

First Meter:
*Manufacturer -- Scientech (Model 365)
*How old the meter is -- Don't remember.  Will have to look up the manufacture date.
*What type of meter is it - Volume absorbing thermal head.
*Capabilities of the meter -- The ranges are .01W up to 20W.
*How you use it -- Zero it out, shine the laser, watch the digital readout.
*What you measure -- Personal lasers, lasers for others.
*WHY you bought the one that you did  -- First LPM and I "NEEDED" it  Ebay is your friend!!!!!


Second Meter:
*Manufacturer -- Knimrod DIY LPM
*How old the meter is -- Built it during the DIY LPM Thread
*What type of meter is it - Volume absorbing thermal head
*capabilities of the meter -- not sure
*HOW you use it -- zero it out, shine the laser , watch the digital meter
*What you measure -- personal lasers, lasers for others
*WHY you bought the one that you did  -- was a DIY project. (I love projects) (Also provided a means to graph the laser power vs. time)
Just a FYI---  This meter is within 1mW of my Scientech 365!!!

 

[billg519]

I have currently two laser power meters.

Coherent Lasercheck (purchased from Edmund Optical, has EO logo, but coherent instructions, case, serial # label, and coherent calibration certificate)
Meter is about 6 months old
Silicon Cell type meter
Range 10 microwatts to 1 watt
Use by selecting wavelength, then press button while shining laser on sensor
Used for primarily my own DIY or purchased lasers.
Purchased because I want to know what my lasers are doing, rather than guessing.
Issues - cheap greens seem to massively overread on this meter, possibly due to IR leakage fouling up the meter



Coherent Model 210 Analog LPM with Coherent 210 Thermal Head
Age is unknown, came from ebay 2 months ago in very good condition
Thermal type meter
Range 50mw to 10 watts in 4 ranges
Use by turning knob to desired range, shine laser into thermal head
Used for my own DIY and purchased lasers, especially my handheld IR projects
Purchased because I've always wanted a thermal type meter, no issues measuring cheap IR leaky greens


I like the lasercheck for its shirt pocket portability, and the ability to measure low output helium neons. The lasercheck must be set to the wavelength to be measured. This makes it less desireable when I get some IR laser diodes of unknown nm's for cheap, as I can't get an accurate reading if not sure of the nm's. My particular lasercheck also grossly overstates the power of most green lasers, even if I expand the beam to the size of the sensor. For instance, I have a DX 200mw green, 18650 battery type, that reads 269 mw on the lasercheck. This laser, however, is very weak. It doesn't pop baloons, can barely light a sharpied match or cut black tape. It's true output is 75mw, as established with my Coherent 210. The IR emissions from the cheap greens must be fouling up the frequency sensitive lasercheck.

For bench use, I prefer my Coherent 210. Not as portable, but goes up to 10 watts for my lower powered IR work.
This thermal LPM is not frequency sensitive, so if I get bargain c-mounts of unknown nm's, I can test their power with this meter. Greens that leak IR do not fool this meter like they can fool my lasercheck. Its old, its analog, but I like it.

Maybe someday I'll nut up and get a Fieldmaster ...