Night Vision Emission Point Question

[Scwalker83]

For those of you who are seasoned NV people can you answer a few questions for me? A little back story on the issue, I bought a used PVS-14 from tacswap.com about a week ago. Listing did not disclose that it had an emission point on on it. I turn the unit on with a cap over the ocular and there is a very noticeable white emission spot.

The emission point is barely noticeable outside of complete darkness, ie with a solid cap on the ocular eliminating any light entering the unit.

I brought the issues up with the seller and they indicated to me that it must've been me rough handling the unit or shipment. Can emission points occur after manufacture? I'm not knowledgeable enough in this matter.

What's the likelihood of the emission point growing? If that is even something that is worthwhile to be speculated upon.

An example of probably where I should've just placed a back order and gone through an established vendor.

 

[CoryT]

Emission points can grow or multiply over time, depending on the cause. A point that dims as the gain or system brightness increases is not usually a problem. A bright point that remains bright from total darkness (capped solidly) though to min gain bright light is normally noted as a unit failure and gets replaced. If the spot dims as the light increases and it is not in a zone that affects the ability of the operator then it gets marked serviceable.

 

[CoryT]

If the cause is a flaking of the substrate, additional flaking/arcing may occur. If it is a flaw if the coating it will not change much over time. Points like this can be laser repaired, but I’m not sure that’s cost effective

 

[Old Man with Gun]

Used gear is always a big gamble. No way to know how many hours on it or how it was treated.

 

[Scwalker83]

Thanks for the input on this guys. This emission most certainly dims and is barely/not noticeable during normal operation. It was egregious on the sellers part to omit the emission point in the first place.

 

[CoryT]

That depends on if it was there and he noticed it. Its entirely possible he missed it or it was not there last time he looked. One reason I always do a pic through the tube, sometimes you just don’t see it in use.

 

[Scwalker83]

That depends on if it was there and he noticed it. Its entirely possible he missed it or it was not there last time he looked. One reason I always do a pic through the tube, sometimes you just don’t see it in use.

I asked to return the item and pay shipping both ways and was told to pound sand. If I didn't mention something like this in a listing it would be lying through omission. Even if I didn't know about it at the time of sale, ignorance is no excuse, I would make it right.

 

[CoryT]

My inclination is to fix things like that, for example I just exchanged a Vector 21 that the buyer says has a dim display. I did not see that, I would not have sent it out if I did. I personally test every device I sell. That does not make me infallible. Solution? Ship a replacement, carefully checked for proper display operation. No replacement available? I take it back and refund price less shipping. That's just me though, and it's wise to check on the return policy on items where you may have concerns. In this case, the item at least seems usable and you know not to use that seller again. You can leave feedback to advise others and be more careful the next time.

Given your description of the problem, I would not be very worried about it getting any worse. Flakes or arcs don't dim at all, so you should be fine.