Coherent Lasercheck or similar?

[Galvonaut]

Looking for a new or used lasercheck or similar silicon power meter.

Thanks

Keith

[The_Doctor]

It was a few years ago now, but there was a guy in Australia who posted on Usenet answering me on the same call. New meters with calibration, and at least twenty quid cheaper than any other new one by the time I got it, customs charges done, etc. It;s too long since then to remember more detail, but it might be worth posting to alt.lasers on usenet in case he's still using it.

[badger1666]

Why would you want one of these ?
Very limited power reading wise you would be better off
Getting an ophir head and using a dmm to read it,or get a 5 digit mv display of ebay
Put it in a box with rechargable batteries to power the head and display.
That what i did then you have a 5 watt+ power meter for reasonable money
Or if your not up for that check out the laserbee power meters

[sbk]

I have a Lasercheck sitting on the desk for a while, if you're interested.

[The_Doctor]

..you would be better off getting an ophir head and using a dmm to read it,or get a 5 digit mv display of ebay

Seconded. That really IS worth doing. If they already come with calibration it solves everythign except easy pulse measures. And for more than 5W you may be no worse off with a carefully adapted meat thermometer. Not joking... I remember Sam Goldwasser discussing this on Usenet.

The main problem with a Lasercheck isn't the power, you can always add neutral density filters. Its main problem is wavelength dependency, and diodes are often not known well enough, and parts of the curve slope are steep so accuracy fails. The battery in a LaserCheck is not easy to get or replace without damage too, a BAD feature for such a costly instrument! They last a while, but have been known to fail early. But they do score for convenience at times. I sold mine on during my 6-year absence from PL, but I still use a Scientech head with a circuit carefully calibrated with it before I sold it. It's enough, for now...

[krazer]

The lasercheck is very useful for measuring low powers, an ophir thermopile head might be able to resolve down to the mw, but can't possibly measure anything less than 10mw with any reasonable accuracy, where as the lasercheck reads down to 0.00001mw. Its also a lot easier to take with you and fit into tight places ;-)

[JStewart]

Depends what you want the detector for.

Thermal detectors are great for measuring laser performance, (i.e. output power).

If you want a convenient all-in-one device for checking exposure levels against MPE levels, then a silicon based Lasercheck is a really useful tool.

A thermal detector just does not have the ability to resolve down to the levels for safe exposure levels when comparing with the MPE. Nor do they react as fast, making the finding of hotspots more difficult. The downside of silicon though is, as others have pointed out, the fact the response varies based on the wavelength being measured.

James

[Galvonaut]

Just received a PM re. a LaserCheck. Thank you

As James has pointed out (and taught me last week) a semiconductor photodiode has the resolution to check for audience bound emissions and at this stage I am more concerned with this than with raw power measurements at the aperture, although I will be in the market for thermal detector once my severely suffering bank balance has recovered from my recent laser-related purchases!

Krazer: Yes, very portable! I will have to resist the temptation to take it clubbing in Worthing where I have seen 2x 3 Watt lasers hitting the audience within about 1.5m!

Keith