Prefered Term for Lens/Window

The covering over the photon port of a flashlight is a most important item. The typical term, "lens", isn't accurate unless it introduces correction to the light.

"Window" has been gaining acceptance for describing the clear, flat, noncorrecting, disc used on most flashlights.

This poll is an attempt to acquire a concensus regarding proper terminology and to avoid confusion when mentioning the above item.

What is your opinion and why? Thank you to all respondents.

This is really becoming quite laughable.

Shall we now refer to cosmetic contact "lens" as contact windows?

Shall we refer to safety glass inserts as windows?

Shall we abandon terminology such as "corrective lenses" and "plano lenses", as redundancy and oxymorons, and just go to mundane but technically specific terms like lens and windows?

Use whatever term is necessary in conveying your meaning toward those with whom you're dealing. If you're making a light and the supplier of the little glass plate is so hung up on pedantics that they insist that the use of the term "lens" must be used according to their rules, then by all means feel free to use the term "window". Real opticians apparently don't suffer the same affliction, since it's their trade that has produced the term lens and lenses even when applied to contacts, safety glasses or goggles. The pedantics have lost, and the laymen have latched onto the term "lens".

Lens! Lens! LENS! It's your term. You've used it for years. The pedantics have lost any exclusivity involving it. Use it in pride.

The contacts I wear (not the ones I have in the Senate) do correct the image so they qualify as lenses.

CPF members, generally, seem to prefer accuracy and differentiate between cells & batteries, LED bin types, incan lamp gas chemistry, anodizing types - going so far as to point out HA III is redundant.

Enough of our members have expressed opinions re. lens vs. window that I was curious what a discussion on the subject might reveal. As previously stated, I'm fine (for now) with lens as a nonspecific, generic, term. Others have expressed interest in pedantism and specificity.

I've enjoyed the the outright and unintended humor in these threads, yours included, Empath.

The Dorcy AAA & some Inova are the only flashlights I know that has both collimator lens & reflector versions. I have to be careful with these lights. Otherwise I just use lens. I'm a hunt & peck typist & I have to hunt 2 less characters.

Edit Use both. Use them all.
I got My Little Friend today. It has a Fraen tri OPTIC collimating LENS behind a mineral glass WINDOW.

Not that left, the other left...

This is typically said in fun and as a jibe but if you had told someone to shoot the bad guy on their left, one would hope the message was properly understood. :green:

On Under Water camera housings, the front glass that lets the light into the housing is typically called a port. It may be a simple flat glass (which does effect light path UW or it may be a dome which corrects for light being bent as it travels from water into air or it can be a lens such as a macro port which allows the camera to get closer to subject. I think it is a good term and there is no ambiguity in its use and context.

The use of window on a flashlight is specific in defining its effect on the light but if it is not understood to be what it is in communication then it is a poor choice of term. Lens is more commonly understood and used as the term and that is fine provided the communication is about a part that exists and is being discussed. If the communication is in regards to a light that is being designed or component selection is at hand, lens might not be specific enough.

As a builder and designer, I have to identify the various components and their designation needs to be clear and unique enough to insure proper identification. In a parts break down drawing, either term, lens or window, could be used as a tag and the drawing would likely provide more information. In the absense of a drawing, an ambiguity in term could be a problem.

I.E. (and this will let me whine about SF's use or as I see it, misuse of bezel) consider the KL1 head.

This part consists of (from the front) a bezel (female thread so I consider it a cap), a thin washer, a window, a seal, the TIR lens and then the head itself. I leave out the light engine components in this example.

Now if you were to call SF parts department in need of say the bezel and said I need a KL1 bezel, just send it to me!! Well it is likely that you would receive the complete KL1 given SF's propensity to identify the whole head of a light as a bezel! :nana:

If you broke the window and called SF parts and in a rush just said send me a new lens for the KL1, you might get the window or you might get the TIR optic. If you receivd the optic and needed the window, you might not be happy with SF parts department.

I don't give a rats a$$ what parts are called; perhaps they should be named fred ted and ed. The only important consideration is that of communication and the required accuracy in identity in such communication. I just had my wife ship me some LED light components I need over here and one item I wanted is a LED light fixture which looks like a hollow threaded bolt. I got some pipe nipples in place of what I really needed. Forgive me my concern and perception for thinking specific and unambigious terms are best to use! :nana:

Now this poll seems to me to have two choices which are the two sides of the same coin?!?! :thinking: :shrug:

The layman can measure a lights length with a ruler. The designer or machine shop needs a more precise measuring tool. The layman can use the ruler or a caliper. If the machinist uses a ruler, I don't want one of his parts!

EDIT:

Now that I am on a roll, there is an underlying dynamic I see at play here and at play is a good choice of term. In a car load of people, all but the driver can take in the scenery and engage in discusions and focus their concentration on issues beyond the traffic and road. They have the luxury of levity and casual awareness that the driver is not free to assume. On this forum and in some threads, there are drivers and there are passengers at times and it helps to be aware of the various responsibilities of the players. Oh yeah, plenty of back seat drivers too! :nana:

I have seen numerous examples of CAD renderings posted on this forum that look great to the casual and unskilled observer but are obviously flawed and faulty. The passenger takes it on faith that the driver knows what he is doing and will bring the group to the intended destination with no harm or mishap. The driver wants to enjoy the company of his fellow passengers but also needs to pay attention to the road being traveled and concentrate at an acceptable level. I think I had a point somewhere in here! :green: :thinking:

Yes, exactly, precisely what you said, I think, maybe, McGiz (is there any more) mo. Mo on the serious-er side...those are good points.

Another advantage of an exact term (if it's understood) is an additional sentance or more is not needed to explain whether the item is a real lens or just a window lens.

Through the looking glass we go - just a plano one. A plane new one may also suffice. Somebody else take over, please.

Now do you see what y'all have done?

You've got people talking to each other with mixed terminology, which doesn't do anything to improve communication nor understanding. You've created a little tower of Babel incident.

It's remarkable, with the different nuances and meanings applied to words, that we can understand one another as well as we do. Creating confusion under the guise of clarity doesn't help at all.

Of the greatest pleasures being a flashaholic and CPF member has been the humor, both in these forums and that enjoyed with my family. Flashlights have become the source and butt of frequent hilarity between my 12 year old daughter and I. The discourse in this thread has raised its humorous head, so let us laugh at ourselves and our foibles. The "outside" world thinks we're nuts, anyway.

My intentions we're to help create clairity where none existed. Apparently I should have had a clue because this issue wasn't already settled, complete with appropriate acronymns in the CPF FAQs.

With the CPF staff unable to agree, we rank and file members will continue to stumble over semantics while drooling over the latest rage (as opposed to Rage, Impact, Surge, or bad Attitudes)

i just look at the pictures call everything a thingymagig, just show me a pic and provide realistic specs or descriptions.

just to go completly off topic:
used to be ,long ago, you would go into the hardware store, and get a piece of METAL, that was a certian size and shape close to what you what you needed. all the "metal" was basically in the same location. go to the metal isle, and find what you needed.
now "metal" just general metal is a small section , but metal you need for a project could be in 101 locations in the store. so if you need metal you have to go into every department in the store, as it is not just a hunk of extruded elements anymore it has some grand purpose in life.
so its just a hunk of glass, it may be of a certian type, size, temprament and thickness, but its just glass, so dont make me go looking all over the store for it , , OK

back on topic, did you know that normal glass causes (up to) a 10% reduction , and plastic only a 5-8% reduction when used in solar applications?
i had not known that untill i made a solar pannel, and tested glass vrses plastic and found out they were not kidding. i always wondered what that meant to a flashlight or light. they have UCL but if you pass a laser through UCL it does not pass through uninterupted.

How about port hole glass?

Chalk me up as a lens kind of guy.

How does the g'vt order them? Maybe we should use their nomenclature.

This is certainly something that should be cleared up right away, seeing as how it's been going on so long. The first thing we need to do is to solicit apologies from the pioneers of the flashlight industry for interjecting such confusing terms; they and the hardware stores of my childhood days that sold the replacement glass lenses/windows/whatchamacallits before the days of plastic ones in displays calling them flashlight lenses.

We can come to grips with this thing by coining our own correct and applicable term for the appliance. We can call them quantum/non-quantum regulating sieves, or QnQS for short. After all, their purpose is to regulate and permit the passage of the quantum particles in one direction, while serving as a barrier against those pesky non-quantum thingamajigs in the other direction. We can even get fancy by referring to them as a Q/nQS. When the industrial leaders act confused by our terms, we can give them that smug look, as if to show contempt for their inability to come to grips with the prior confusing terminology.

Those smilies should be a tongue-in-cheek representation, but it's not as obvious as should be. I just felt this called for such.

Really, though, it should be sufficient to speak in terms your audience understands, and accept with understanding what you know is intended. While teaching those that need clarification seems good, there are times the effort only adds to the confusion.

We agree, Emapth, in that unfamiliar terminology would only be confusing to the uninitiated and, therefore, I don't refer to the lens as a window unless I'm on board, here at the CPF. If we are CLEAR with our choice of terms no "official", CPF approved, word is necessary. Looks like lens leads the poll, anyway.

Of course, just for fun, we could argue this until the next summer solstice.

I used to call them all lenses until I read a few threads a few months back that won me over. I'd rather step back in conversation once in a while if someone doesn't understand than always use a term I believe is wrong. I don't think it's that confusing. I'd even bet that outside CPF there are more folks who know what a window is than a lens.

But who am I? I still pronounce arctic arc'-tic, as opposed to the much more common ar'-tic.

As long as we don't go nuclear with pronunciation.

I prefer Light Enabling Neutral Surface.

Zero opacity silicon based thingy. Or window (truth be told a lense bends light or magnifies and concentrates it.