View Full Version : Etched reticle explained

05-23-11, 20:57
Would somebody please explain to me what an "etched" reticle is? I just received an explanation from a manufacturer that contradicts my previous understanding.

As the phrase "etched reticle" suggests, I thought the reticle was/is actually etched onto the glass. That's is not what I was told.

Someone please explain. Thanks

05-24-11, 05:17
I thought the reticle was/is actually etched onto the glass.

That is my understanding: etched reticles are the result of removing material from a lens within the tube.

I am curious as to what you were told by said manufacturer.

ETA- FWIW, Wikipedia agrees with us. :rolleyes:

05-24-11, 06:25
From unnamed said manufacturer.....

"That scope definitely does have a glass etched reticle and it is held in place with a lock ring. There is a bonding agent on the lock ring and the edge of the glass plate that the reticle is etched onto for added strength"


"the way this reticle is held in place is pretty standard practice for any glass etched reticle...."

So, what do you think?

05-24-11, 06:48
It sounds to me like the guy is explaining how the lens is secured within the tube.

05-24-11, 07:00
My concern expressed to said manufacturer is a non-etched reticle coming loose and this is the response I received. If his explanation of etched reticle is accurate, then all scopes have the same potential for failure - reticle coming loose and cross hair lines shifting. :confused:

05-24-11, 08:39
"ETA- FWIW, Wikipedia agrees with us."

I wouldn't trust a damn thing that comes from Wikipedia!

05-24-11, 09:49
...then all scopes have the same potential for failure - reticle coming loose and cross hair lines shifting. :confused:

Yes, but only because that's always been the case with optics. Anything made by man us mutable to begin with, and the little old lady likes to show up to the factory drunk from time to time.

This is true of any internal component; if any lens/prism inside a scope comes loose, there will be actual or apparent shift of the reticle. In the case of an etched reticle, it's etched onto a lens (usually by laser, these days, as there's no lands/grooves/jeweling as with use of an actual machine bit) and therefore the entire reticle moves if what it's etched onto comes loose, instead of, say, seeing a mil-dot hanging like an overripe pomegranate prior to watching it fall out of the FOV.

It's unusual, but there's still some optics out there made with an etched reticle on an independent piece of glass and set in front of a lens, but that's needless parallax, extra airspace, extra possible failure point, etc., so it's not common. The same circumstances apply; lens/glass shifts = apparent/actual shift of the reticle. This is the Luddite approach to an etched reticle, in comparative terms, as etching onto actual lenses isn't all that complex in the modern manufacturing sense.

05-24-11, 10:29
"ETA- FWIW, Wikipedia agrees with us."

I wouldn't trust a damn thing that comes from Wikipedia!

Thus the "FWIW" :sarcastic:

05-24-11, 12:58
Santoro, your explanation is consistent with my thoughts of etching. I will provide more info with personal experience once it's resolved. Needless to say, I'm shocked by what I'm hearing from said manufacturer. I didn't think "etched glass" was a subjective phrase.

05-24-11, 14:22
It's subjective only to the ignorant, to an engineer, or to somebody trying to sell you something shitty. :D

05-24-11, 21:02
It's subjective only to the ignorant, to an engineer, or to somebody trying to sell you something shitty. :D

Nice. When this is resolved, I'm gonna quote you on this. :).

05-25-11, 20:41
From what I understand, wire reticles are just that -- thin filaments of wire. They are susceptible to breakage. Adjustments move the position of the wire reticule with respect to the glass.

An etched reticule etches the reticule into the lens -- far less chance of breakage from normal use. Reticule adjustments actually move the lens.

Like wikipedia, FWIW. But that's really no different than any message board, a coalition of the willing......

05-29-11, 10:14
It's subjective only to the ignorant, to an engineer, or to somebody trying to sell you something shitty. :D

Okay, so here is the final story on the etched reticle question.

I have been in contact with VORTEX regarding the PST 1-4x. I experienced a reticle "shift" with my PST. I sent the scope in (great CS!) for review. The confusing part about the explanation of an "etched reticle" is that Vortex refers to the "reticle" as the glass and sighting element as one. I was referring to the reticle as the sighting element.

After a lengthy phone discussion from the scope tech at Vortex, I learned the PST does have an "etched on" reticle. As Vortex describes it, the reticle is held in place with three set screws, which are then glued or bonded to hold their place. If the bonding were to brake loose, which occured on my scope, the reticle pane would "shift" - which mine did.

While I'm not prepared to call my PST shitty, the jury is definitely gonna deliberate a little longer! The one redeeming thing, the customer service at Vortex rocks. They overnighted a scope the next day.

05-29-11, 21:18
OoooooooOOOOOooooohhhh, it's a 'sighting element,' now.....

Sooo...engineers, it is. ;)

Regardless, glad to hear that they're working the problem in a timely manner.

05-31-11, 12:55
I'm very aware of your situation and have discussed it at length with our repair techs and the customer service department so let me clear a few things up here.

The 1-4x24 PST does have a glass etched reticle. It appears there is some confusion about what that actually means. A glass etched reticle simply means that the reticle pattern is etched onto a plate of glass. This is typically done using a photo-lithographic process.

Additionally, the glass etched reticle often has a cover plate that is bonded on top of the glass surface that has the reticle etched onto it. This means the reticle pattern itself ends up sandwiched between two plates of glass, so short of the glass plates literally cracking (pretty much unheard of) the reticle pattern cannot "break".

Then that plate of glass with the etched reticle is installed into the rifle scope. This is standard practice for glass etched reticles in nearly all high end rifle scopes.

The other common method is to have a reticle that is literally a very thin piece of metal foil that has everything except the reticle pattern and an outer ring etched away. The outer ring of the foil is then glued to a "washer" and that is installed into the scope.

Unlike glass etched reticles the metal reticles can break because the reticle itself has no support except itself. In other words, there is just air all around the reticle features. If enough force is put on one of the metal lines it can literally tear away or break off of the other parts of the reticle. Because a metal reticle supports itself a dead giveaway that a reticle is a glass etched reticle is if it has floating features (such as in the 1-4x24 PST). There is no way that a metal reticle can have floating features because there is nothing there to support the reticle feature that is floating and keep it in place.

So, for example, in the 1-4x24 PST the entire reticle itself floats in the center of the FOV with no connecting lines from the outer edge of the FOV. Not to mention the center dot, outer four-sectioned circle, and the text above the reticle. The only way to do this is to etch the reticle pattern on a plate of glass.

Any reticle can shift it's POI. This can happen if the entire reticle assembly moves because it isn't secured in its mount properly, or if the erector tube that the reticle is installed in shifts.

As for your particular PST I talked to my tech and he tested your PST extensively and could not get the reticle to shift and couldn't find anything wrong with it. Regardless, we did send you a new one anyway.

I hope you find the new one more satisfactory.


05-31-11, 13:31
Sam, thanks for the detailed explanation of an "etched reticle". The time I spent talking with your optics tech gave me a better understanding of the PST and its quality. I trust his findings and whats more, he gave me a confident feeling about the scope mailed to me to replace the one in question.

As I mentioned, the customer service has been exemplary. I am sure three will be my lucky number!