# Lens: Plastic vs. Glass / What's Your Preference?



## LEDAdd1ct (Dec 27, 2014)

Ultra-clear glass lenses let the most light out while Borofloats are great for high-temp incan setups. 
Plastic is seen as being highly unfashionable, and it was certainly not my preference.
However, this evening my bias may have been swayed in the other direction. 

Came home today tired and with sore knees, and threw my keys/lanyard on the hook, inadvertently knocking over my Mag Charger triple LED XM-L2 setup. I watched in slow motion as it hit the tiled foyer at a steep angle, bezel down, and watched glass go everywhere. Spent the next hour vacuuming up shards of glass from the carpet mat, the stairs, the shoes/hiking boots/sandals...royal pain in the behind. The three little reflectors popped off and I scooped them up off the floor for later re-adhesion. Now that I had an instant mule, I used it to see as many shiny little fragments of glass as I could find. 

I'll borrow a plastic lens from one of my other Mags and figure out a way to glue the reflectors back on. 

To say I am now soured on using a glass lens for the heavier lights in my collection is an understatement. 

So, fellow members, which do you prefer? 

I am not talking about super high temperature hotwires where you don't have a choice, but, if you could use either a UCL or plastic lens, which would you use? Is the higher light transmittance of glass, the risk, worth it to you? 

I am adding a poll to this thread. 

I am 80% sure I got all the little shards up, but will be scared for several weeks about finding a "present" in my shoe or embedded in the sole of my foot.


----------



## FlashKat (Dec 27, 2014)

I prefer glass, and if possible get a lens that is thicker.


----------



## ShineOnYouCrazyDiamond (Dec 27, 2014)

I voted for glass. Plastic gets scratched up way to quickly. Makes me think back to the MagLite AA days where the plastic lens would end up terribly scratched over time. Don't think it impacted the beam that much but looked quite unsightly.


----------



## archimedes (Dec 28, 2014)

Can I vote for sapphire ... ?


----------



## Slumber (Dec 28, 2014)

I prefer glass, but I don't mind plastic as long as it's user serviceable.


----------



## skyfire (Dec 28, 2014)

glass.

ive had a few surefires where the plastic lens was so scratched up, that i couldnt stand the beam. had to replace them with glass lens.

all the lights i use have smallish bezels, and lens. less risk of the glass lens breaking when being dropped. and if i do break the lens, i can easily replace it on most my lights (surefires).

i had a quark turbo, and my biggest complaint about it was that its lens seemed very vulnerable. it was wide, thin, and had very little bezel to protect it. 
i ended up selling it and the main reason was because i wasnt confident that the lens would survive a drop. so i kind of know how you feel. 

about a month ago while cooking, a glass lid for a 15 inch frying pan fell, and the shattered glass was spread all across the kitchen floor, as well as knocking over a bottle of olive oil on its way to the ground, spilling oil. fortunately, the glass bottle didnt break. all the while have food cooking over the stoves.
lets just stay there was an outburst of cursing and swearing when it all happened....


----------



## LEDAdd1ct (Dec 28, 2014)

I agree that plastic (any plastic lens I've owned in a light) scratches way too easily. On my 18650 lights, it is a non-issue, as there simply isn't enough mass to shatter the lens unless you drop it in a very unfortunate manner. I am speaking specifically of larger lights. 

A Mag Charger host + Massive heatsink for three XM-L2 LEDs + 26650 cell + Spacer = HEAVY

Hey people up in Corning, when are we gonna get our Gorilla Glass flashlight lenses...?


----------



## ShineOnYouCrazyDiamond (Dec 28, 2014)

archimedes said:


> Can I vote for sapphire ... ?



I assumed glass covered Borofloat, UCL, mineral, sapphire, etc so I think you are covered there.


----------



## LEDAdd1ct (Dec 28, 2014)

Yes, that is correct:

Genus = Glass

Species = Borofloat, UCL, mineral, sapphire, etc...


----------



## kj2 (Dec 28, 2014)

Prefer glass.


----------



## idleprocess (Dec 28, 2014)

I use borofloat lenses on some of my lights because of the scratch resistance and toughness, but I know this costs a little on the output side; anything other than thin and relatively fragile UCL-type glass absorbs appreciably more light than humble polycarbonate. Polycarbonate is cheap, lightweight, and spares *Should™* be readily available for next to nothing for when the lens inevitably gets scratched up to the point that it starts to hurt performance ... but the market does not always provide.


----------



## onetrickpony (Dec 28, 2014)

archimedes said:


> Can I vote for sapphire ... ?



Sure, as long as you're not GT Advanced Technologies. http://www.wsj.com/articles/gt-advanced-technologies-files-for-bankruptcy-1412607074


----------



## LEDAdd1ct (Dec 28, 2014)

idleprocess said:


> ...anything other than thin and relatively fragile UCL-type glass absorbs appreciably more light than humble polycarbonate. Polycarbonate is cheap, lightweight, and spares *Should™* be readily available for next to nothing for when the lens inevitably gets scratched up to the point that it starts to hurt performance ... but the market does not always provide.



I checked e-Bay for Mag-size polycarbonate lenses, and all I could find was this absurd listing.

Anything weird about this description?


----------



## DAN92 (Dec 28, 2014)

ShineOnYouCrazyDiamond said:


> I voted for glass. Plastic gets scratched up way to quickly.


I prefer the glass for the same reason.



FlashKat said:


> I prefer glass, and if possible get a lens that is thicker.


It is better.


----------



## KITROBASKIN (Dec 28, 2014)

It has been reported that ZebraLight uses Gorilla Glass on some of their flashlights. Schott glass is said to be used on other (older?) ZL's. I use shockcord lanyards and slightly modified Nite-Ize headstraps on all of my lights, even the large glass lens NiteCore TM36, to lessen the chance of dropping. I could see for hard-use shop-flashlights, polycarbonate may be the way to go; otherwise, glass is the choice.


CandlePowerForums App


----------



## ForrestChump (Dec 28, 2014)

I wonder which one CPF likes better, glass or plastic? 


:duh2:


----------



## LEDAdd1ct (Dec 28, 2014)

So far the folks who have voted in the poll like glass!


----------



## idleprocess (Dec 28, 2014)

LEDAdd1ct said:


> I checked e-Bay for Mag-size polycarbonate lenses, and all I could find was this absurd listing.
> 
> Anything weird about this description?


It was written by someone that never misses their 4:20 appointment?


----------



## LEDAdd1ct (Dec 28, 2014)

Nope!

Read the caption under the blue title and above the price...


----------



## MidnightDistortions (Dec 28, 2014)

I do prefer glass but the last thing i'd want is for the glass to shatter, especially in a bad location. Even though i chose glass over plastic, plastic isn't as dangerous. But the only reason why i'd want glass over plastic is that the plastic easily scratches. It looks bad, flashlights could use a better coating plastic that is scratch resistant. Glass doesn't have that problem only i would have to make sure i won't drop a flashlight with a glass lens.


----------



## RI Chevy (Dec 28, 2014)

Glass.


----------



## idleprocess (Dec 28, 2014)

LEDAdd1ct said:


> Nope!
> 
> Read the caption under the blue title and above the price...


The total non-sequitur is why I thought the price played into it. But perhaps there's some reference there I missed.


----------



## Grizzman (Dec 28, 2014)

My vote is that it depends. Since that wasn't an option, I chose plastic.

My larger lights (Malkoffs and Maglites) all have non-glass lenses, and I prefer this for the improved durability. If they get scratched, it is easy to replace the lens. My weapon mounted lights use Acrylic or poly-carbonate lenses for this same reason.

For other lights, I prefer sapphire or glass.


----------



## newbie66 (Dec 28, 2014)

My local dealer for Pelican once told me that a customer had to send his Surefire back for fixing because the plastic lens melted when he accidently left it on head down on the table.


----------



## Bullzeyebill (Dec 29, 2014)

newbie66 said:


> My local dealer for Pelican once told me that a customer had to send his Surefire back for fixing because the plastic lens melted when he accidently left it on head down on the table.



That happened to me when I accidentally put a 9P with a lexan window, down on its bezel, using two 18500's with the P91. Burned a spot on my table. I also have an original G2 with a partially melted window.

Bill


----------



## liveris flashlights (Dec 29, 2014)

archimedes said:


> Can I vote for sapphire ... ?


Sapphire too.


----------



## newbie66 (Dec 29, 2014)

Bullzeyebill said:


> That happened to me when I accidentally put a 9P with a lexan window, down on its bezel, using two 18500's with the P91. Burned a spot on my table. I also have an original G2 with a partially melted window.
> 
> Bill



That is terrible. The light must be somewhat unusable now isn't it? It's durability compromised, ugly beam. 

I am now afraid to leave my G2X Pro on for too long without a break.


----------



## DAN92 (Dec 29, 2014)

Grizzman said:


> My vote is that it depends. Since that wasn't an option, I chose plastic.
> 
> 
> My larger lights (Malkoffs and Maglites) all have non-glass lenses, and I prefer this for the improved durability. If they get scratched, it is easy to replace the lens. My weapon mounted lights use Acrylic or poly-carbonate lenses for this same reason.
> ...


You're not wrong, I use a Malkoff M60 on my shotgun.


----------



## ForrestChump (Dec 29, 2014)

newbie66 said:


> That is terrible. The light must be somewhat unusable now isn't it? It's durability compromised, ugly beam.
> 
> I am now afraid to leave my G2X Pro on for too long without a break.




This is a non issue. He place a 3 cell hot running light bezel down on a table. ( stuff happens ) It got hot enough to burn the table.

Don't leave any light on Hi bezel down. Its not designed for that. You won't have anything near those results with normal use.


----------



## NoNotAgain (Dec 29, 2014)

LEDAdd1ct said:


> Nope!
> 
> Read the caption under the blue title and above the price...



That way you can store your newly lens replaced light in a sock for additional safety.


----------



## Bullzeyebill (Dec 29, 2014)

newbie66 said:


> That is terrible. The light must be somewhat unusable now isn't it? It's durability compromised, ugly beam.
> 
> I am now afraid to leave my G2X Pro on for too long without a break.



Thinking more about it, it actually was an older G2 running two RCR123's. It deformed the lens, but beam quality was not adversely affected. Center beam was somewhat larger.

Bill


----------



## LEDAdd1ct (Dec 30, 2014)

The market beckons:

With all the custom stuff floating around out there, why don't we have a polycarbonate lens with high light transmission _or _a shatter-proof glass lens?


----------



## ShineOnYouCrazyDiamond (Dec 30, 2014)

idleprocess said:


> I use borofloat lenses on some of my lights because of the scratch resistance and toughness, but I know this costs a little on the output side; _*anything other than thin and relatively fragile UCL-type glass absorbs appreciably more light than humble polycarbonate.*_ Polycarbonate is cheap, lightweight, and spares *Should™* be readily available for next to nothing for when the lens inevitably gets scratched up to the point that it starts to hurt performance ... but the market does not always provide.



Can you please let me know your source for this information? Are there some specs somewhere that show the plastic allowing through more light that glass options?


----------



## LEDAdd1ct (Dec 30, 2014)




----------



## idleprocess (Dec 30, 2014)

ShineOnYouCrazyDiamond said:


> Can you please let me know your source for this information? Are there some specs somewhere that show the plastic allowing through more light that glass options?



Flashlightlens.com indicates transmittance on all their products ... only they don't carry polycarbonate so I'm going on memory from years back.


----------



## ShineOnYouCrazyDiamond (Dec 30, 2014)

idleprocess said:


> Flashlightlens.com indicates transmittance on all their products ... only they don't carry polycarbonate so I'm going on memory from years back.



Very cool site - thanks. That just joined my list of flashaholic bookmarks. But that being said the glass lenses they offer range from 95-99% transmittance and the plastics they offer range in about the same area. That said I think transmittance needs to be removed as a criteria for the plastic/glass arguement.


----------



## idleprocess (Dec 30, 2014)

ShineOnYouCrazyDiamond said:


> Very cool site - thanks. That just joined my list of flashaholic bookmarks. But that being said the glass lenses they offer range from 95-99% transmittance and the plastics they offer range in about the same area. That said I think transmittance needs to be removed as a criteria for the plastic/glass arguement.



I recall polycarbonate being higher than borofloat, but have no source, thus could be misremembering.


----------



## Yamabushi (Dec 30, 2014)

I prefer glass in most lights but like plastic in lights I expect to get banged up frequently, e.g., my EDC Fenix E05 and the Fenix E11 in my toolbox. Scratches don't affect the faceted lens of the old single-mode E05 anyway.


----------



## parnass (Dec 30, 2014)

Slumber Pass said:


> I prefer glass, but I don't mind plastic as long as it's user serviceable.



Same here.


----------



## newbie66 (Dec 30, 2014)

Bullzeyebill said:


> Thinking more about it, it actually was an older G2 running two RCR123's. It deformed the lens, but beam quality was not adversely affected. Center beam was somewhat larger.
> 
> Bill



Good to know the lens did not melt completely that would make it unusable.


----------



## idleprocess (Dec 31, 2014)

LEDAdd1ct said:


> The market beckons:
> 
> With all the custom stuff floating around out there, why don't we have a polycarbonate lens with high light transmission _or _a shatter-proof glass lens?



Every material choice is a compromise. Harder materials don't scratch but are brittle. Resilient shatterproof materials a re soft and scratch easily. Composite materials can achieve some of the characteristics of both, but typically introduce their own compromises such as cost, bulk, less transparency, etc.


----------



## Quoddy (Jan 2, 2015)

Either saphire or at least glass with an anti-reflective coating.


----------



## LEDAdd1ct (May 9, 2015)

—about to go to bed and stumbled upon a shatter-proof lens made of acrylic with a claimed 97% light transmittance. 

Google 

* UCLp AR Acrylic Lens*

and it is the first hit.

What do you guys think...?


----------



## zipplet (May 10, 2015)

I voted for glass because of the superior light transmittance available with modern flashlight windows and scratch resistance.



LEDAdd1ct said:


> What do you guys think...?


It sounds interesting however I still worry about scratch resistance. If that can be solved somehow, then I would be interested in trying out a flashlight with a window made of that material.


----------



## mistral (May 10, 2015)

for the serious consumers/ collectors point of view, it alway prefer using the good, tough glass with good coatings unless some users alway have the habits of dropping their equipments then likely tough plactic come in.


----------



## LEDAdd1ct (Aug 17, 2015)

I am planning a 13 watt, a 19 watt, and a 20 watt build, all incandescent.

Do I need Borofloat for all three?


----------



## GearHunter (Aug 19, 2015)

Oops I should read the entire thread before adding my 2 cents...glass ( sapphire ).


----------



## grndslm (Aug 24, 2015)

Considering there isn't a flashlight with sapphire glass lens that I'm aware of...

[There is actually a smartphone with a sapphire screen -- http://www.engadget.com/2014/09/02/kyocera-brigadier-sapphire-screen/ ]

... then I'll stick to the "unbreakable" polycarbonate / plastic.

As a matter of fact, I was enjoying my Thrunite Ti4 on the very first day I brought it to work. Left it in my shirt pocket. Took my shirt off because it was soo hot, forgot the light was there, shook the shirt to shake off some dirt.... screen was cracked. Still works just fine, but it now belongs in the purse of my significant other. Definitely sticking to polycarbonate from hereon out.


----------



## archimedes (Aug 24, 2015)

grndslm said:


> Considering there isn't a flashlight with sapphire glass lens that I'm aware of....



McGizmo have sapphire lenses, and it is an extra cost option for HDS.


----------



## Rick NJ (Aug 24, 2015)

I prefer diamond.

Seriously, with so many spending so much to get the super ultra extra bright, I am surprise there is not a big market for crystal lens. A well made crystal lens should perform so much better than glass.

Well, for now, until I save up enough for a good diamond lens, I stick with my slightly cheaper plastic. Stuff changes so quickly I am afraid the things will be "a disposable" too quickly so it is not worth big investment.


----------



## archimedes (Aug 24, 2015)

A ~$30 sapphire lens on a ~$300 (+) flashlight doesn't seem unreasonable :shrug:


----------



## Slumber (Aug 24, 2015)

Rick NJ said:


> I prefer diamond.
> 
> Seriously, with so many spending so much to get the super ultra extra bright, I am surprise there is not a big market for crystal lens. A well made crystal lens should perform so much better than glass.
> 
> Well, for now, until I save up enough for a good diamond lens, I stick with my slightly cheaper plastic. Stuff changes so quickly I am afraid the things will be "a disposable" too quickly so it is not worth big investment.



Perhaps a diamond lens would be too brittle?


----------



## Rick NJ (Aug 24, 2015)

Slumber Pass said:


> Perhaps a diamond lens would be too brittle?



Arrgh... You are such a kill-joy. But I will be careful. I think it should impress enough girls to make it worth while.

.


----------



## idleprocess (Aug 24, 2015)

Rick NJ said:


> Arrgh... You are such a kill-joy. But I will be careful. I think it should impress enough girls to make it worth while.
> 
> .



A polished _unobtanium_ yard gnome will probably go further in that endeavor.


----------



## grndslm (Aug 25, 2015)

archimedes said:


> A ~$30 sapphire lens on a ~$300 (+) flashlight doesn't seem unreasonable :shrug:



But the fact that the $300 flashlight is really no better than a $40 flashlight that actually puts out twice as many lumens.... is a little unreasonable. The sapphire lens, not so much.


----------



## grndslm (Aug 25, 2015)

archimedes said:


> McGizmo have sapphire lenses, and it is an extra cost option for HDS.



I actually just noticed that about the HDS upgrades after reading the "Do you give lights away as gifts?" thread. Not bad, and great design, but jeez.... I'd rather stick to giving out 30+ gifts than buy one of those for myself.

Do all the McGizmos come with sapphire lenses? Not that I'd buy one of those for myself, either. The "Sapphire 25" is the only one that LOOKS appealing to me, but if I wanted a 1-mode flashlight stuck at 5 Lumens, I'd head to Wal-Mart first!!


----------



## archimedes (Aug 25, 2015)

grndslm said:


> But the fact that the $300 flashlight is really no better than a $40 flashlight that actually puts out twice as many lumens.... is a little unreasonable....



Why do so many people around here buy those $300++ flashlights, then :thinking:

Not that long ago, lots of CPF'rs actually paid that $$$ ... _and waited_ ... for many months, just to be able to get an HDS.


----------



## d88 (Aug 25, 2015)

It probably comes down to what you need your light for. Plastic/Acryllic lens are easy to scratch but they offer more shatter resistance. Sapphire is excellent for scratch resistance but are more susceptible to shattering. Glass is a happy medium between both.

Personally I prefer sapphire to resist scratches on everday lights but if i was say needing to use a dive light, then I'd go for a plastic lens as it would be more resistant to shattering due to the changes in pressure.


----------



## grndslm (Aug 25, 2015)

archimedes said:


> Why do so many people around here buy those $300+ flashlights, then :thinking:
> 
> Not that long ago, lots of CPF'rs actually paid that $$$ ... _and waited_ ... for many months, just to be able to get an HDS.


Some people buy them because they simply like to collect. Some people buy them simply because they have more money than they know what to do with it. Perhaps some people buy them because they don't even know any better. :candle: But more realistically, instead of a building a light that is one feature off from someone's ideal light... they give their buyers exactly what they want! 

Perhaps if someone could explain why a Rotary HDS is worth 8x the price of a Sunwayman V11R, we could all know better. I know I'm not gonna pay 8x the price just for a sapphire lens. Maybe 2x the price, but not 8x. 



d88 said:


> It probably comes down to what you need your light for. Plastic/Acryllic lens are easy to scratch but they offer more shatter resistance. Sapphire is excellent for scratch resistance but are more susceptible to shattering. Glass is a happy medium between both.
> 
> Personally I prefer sapphire to resist scratches on everday lights but if i was say needing to use a dive light, then I'd go for a plastic lens as it would be more resistant to shattering due to the changes in pressure.


Which sapphire lens, in particular, is more susceptible to shattering? That link I showed earlier showed that Kyocera's smartphone's sapphire screen is "virtually indestructable", which means that only a diamond could put a scratch on it. They intentionally jabbed it with table corners, metal corners, concrete corners, etc. No shattering, no scratching.


----------



## Bullzeyebill (Aug 25, 2015)

Would be good if the discussion centers around the OP first post, plastic vs glass. There are other threads that discuss the merits of various flashlights.

Bill


----------



## d88 (Aug 26, 2015)

grndslm said:


> Which sapphire lens, in particular, is more susceptible to shattering? That link I showed earlier showed that Kyocera's smartphone's sapphire screen is "virtually indestructable", which means that only a diamond could put a scratch on it. They intentionally jabbed it with table corners, metal corners, concrete corners, etc. No shattering, no scratching.




In the article you mentioned it states 



> but most smartphone makers are hesitant to swap Gorilla Glass out for it. Sapphire's more difficult to produce, limited in quantity and costs more; more importantly, *it's typically easier to break and harder to bend because the material is more brittle*,



Kudos though to the manufacturer if they've developed a special type of sapphire glass which overcomes the inherent weaknesses of 'standard' sapphire.I've yet though to see this technology be used for the glass lens in a light (unless you know of any flashlight manufacturer using it ?), so at this moment in time, we can only judge the standard fare of sapphire which is used. Therefore, my original points still stand until a light manufacturer uses a special type of hardened sapphire.

This argument of what 'type of glass is better' is nothing new though. Those who collect watches will also be very aware of the strengths/weaknesses of each type of material used for it's 'glass'.


----------



## Sambob (Dec 17, 2015)

Glass definitely, I was given a maglite and the lens looked like someone had used 300 grit sandpaper on It, the reason hey gave It away was "the light Is really dim"(SIGH) I've since put glass In all my lights.


----------



## bykfixer (Dec 19, 2015)

Glass when grams don't matter. 

Yet those with good polycarbonate aint nuthin' to sneeze at.


----------



## emarkd (Dec 19, 2015)

I think most of you guy who are ragging on "plastic" lenses in this thread haven't ever seen a good one. Yes the stock maglite lenses are junk, but there are good polycarbonate lenses out there. I've bought several of the UCLp lenses from flashlightlens.com and they're _amazing _- clearer than a lot of of the factory glass lenses I have, even from reputable brands. Yes their UCL glass lenses are even clearer, technically, but my eyes can't tell the difference. So "plastic" doesn't necessarily equal junk.


----------



## bykfixer (Dec 19, 2015)

^^ this!!!

Malkoff lights come with good plastic lenses. 

I did check 'glass' in the poll but have bought extra lenses from Malkoff.


----------

