Optics, filters probably

[HANKMARS]

I have an idea of what these glass filters may have been used for but, so as not to influence your thinking, I will mention those ideas later. Also, someone may know exactly what they are. The red filter lets absolutely no light, emitted from a blue LED, to pass through it. I may use the red pass filter on a thermal imaging project that I have in the works. I have had these filters for so long that I have only hunches as to where I found them. I did the calcs with the numbers painted on the end but I remember that they seemed not quite right to be the frequency one would guess them to be.

 

[hevans1944]

Hmmm. Maybe you can make a mechanically-scanned color TV camera with this set? Not sure what the cyan or aqua-colored filter would do in such an application though. These are pretty thick pieces of glass... could they be insertable band-pass filters for an optical spectrometer or photometer? I suspect the numbers on the ends are part numbers, not wavelength or frequency indications.

 

[HANKMARS]

Hmmm. Maybe you can make a mechanically-scanned color TV camera with this set? Not sure what the cyan or aqua-colored filter would do in such an application though. These are pretty thick pieces of glass... could they be insertable band-pass filters for an optical spectrometer or photometer? I suspect the numbers on the ends are part numbers, not wavelength or frequency indications.

100% agreed. I'm thinking fire assay, Copper, cobalt , f, who knows?

 

[HANKMARS]

Just quite coincidentally, this red pass film was part of a postal envelope I received. Certainly blocks green and blue effectively. I do realize this post is more suited to a physics or chemical testing lab forum but I am not a member of either. Hey, optics are optics.

 

[HANKMARS]

There is almost a correlation here.