Measuring IR in Various Lasers

I am looking into building a meter that will gauge the amount of IR a laser is emitting. Before I get to involved in this project, are they any devices that currently exist to measure this emission? I know I can use varying techniques with infrared cameras to detect the presence of IR, but I would like to build a ratio or percentage of IR output vs visible light output. Would a filter say for 532mn remove the visible light and not the IR? I could then use my LPM to measure the IR and extract a general percentage then. Any suggestions would be greatly appreciated.

None of the filters I have ever seen have removed 100% of their intended frequency of light or let 100% of the other frequencies through. It would take some very exact measurements to determine how efficiently your filter worked.. and if you could get those measurements you wouldn't need the filter in the first place.

A professional grade LPM will give you a graph of which frequencies it is detecting and at what strength. This would be by far your easiest solution.

My personal observation has been that the conversion is far more efficient at high powers than low ones. As a general rule I assume that at 200mw or more you'll see about 1/10th the IR as visible light. At 5mw the amount of IR and visible light will be about equal.

Spectroscopy Instruments

Something like these?
Dolla dolla bills y'all! Unless you want to turn your pockets out, stick with rough methods, like above. IR filter + LPM is the preferred method.