ever since the iphone 5s, apple has claimedto have sapphire crystal as their iphone camera lens. this includes the iphone 6, and 6s, and eventhe iphone se. sapphire crystal is a man made material thatis extremely hard and almost impossible to scratch with every day objects, since it ranksabout a 9 on mohs scale of hardness, right
apple share face value, next to diamonds. so its a pretty big selling point when a companybrags about using it. tissot, is another company that brags aboutthe sapphire crystal on their watches. it's even written right here on the back.
lets compare tissots sapphire hardness toapples sapphire hardness. these picks let me know where an object fallon moh scale of hardness. glass, even tempered glass or gorilla glasswill always fall at a 5 or 6. plastic will be a 2 or 3, and sapphire willbe an 8 or a 9. as you can see from my picks on this watchface, there is absolutely no mark until a mohs 8 pick leaves the first visible groove. if you remember from my iphone 7 durabilitytest a few days ago, when i scratched the camera lens of the iphone 7 with my pics,it left visible mark at a mohs 6 which lead me to assume that the lens is just regulartempered glass.
since it has the same hardness level. it was only after i made the durability videothat i notice apple still bragging about sapphire on the iphone 7. so... i figured it was time to test all of the 'sapphire'iphone lenses. now, full disclosure, this hurts me. even more so than snapping a phone in half. i'm a camera guy, so deliberately scratchinga camera len, even for science, is extremely painful.
i retested the iphone 7, and got the sameresult. a 6, a 7, and an 8 pick all leave their mark. scratching much sooner than sapphire crystalshould scratch. the 'sapphire' lens on the iphone se alsoscratched with a 6 and 7. the iphone 5s showed marks at a 6 and 7. and even the iphone 6 scratched at a 6 and7. so we can easily conclude that each of theiphone sapphire lenses are much softer than the tissot watch face... at this point, i thought the case was closed.
i got ready to post a video saying apple justisn't using sapphire crystal. but... i grabbed a diamond tester that i have layingaround, and i tested the outer glass surface, and bewilderingly enough it tested positivefor sapphire. which is strange because as we've clearlyseen, the hardness level does not match what sapphire should be. when i test the underside of the lens, thesapphire reading is much lower... also interesting, but ill explain that in just a second. as you can see when i test my tissot watchface it is off the charts in sapphire readings,
but that is only because it is a larger surfacearea and easier for the machine to identify. just for reference, this is a real sapphire. it's pretty small stone, but is still a level9 on mohs scale of hardness. this is just showing the mineral picks inaction, as well as a control for the tester tool. both companies claim to have sapphire, sowhy is there a difference in hardness? i looked at both my tissot watch and iphonecamera lens under a microscope and found some interesting things. first of all, remember that this scratch onthe watch happened at a level 8.
we can see the damage pretty clearly underthe microscope. the thin groove and the little chippings thatpermanently disfigure the crystal. but if we check the sapphire iphone 5s cameralens under the microscope we see something entirely different. remember that this is the mohs 6 line, andthis is the mohs 7 line. the crack here happened as i was lifting thelens out of the iphone frame... the level 6 and 7 picks definitely did permanentdamage, but under a microscope they look like fractures instead of scratches. sill very permanent, and still permanentlydisfiguring the lens.
so its pretty clear that we are working with2 different quality's of crystal here. now that we've seen the damage... lets figureout why the apple lens start to fracture at a mohs 6, when it should be resilient to atleast an 8, like on the tissot watch, or 9 like we saw on the actual sapphire stone. so i checked apples patent for their sapphireinformation, and i found a few strange things. i will link this form down in the video descriptionif you are interested in looking at it yourself. one of the very first things it says is thatapples patent is related to thin sapphire laminates. and then down here it talks about laminatingregular glass with a sapphire coating, instead
of having the whole thing be sapphire. interestingly enough because 'glass may providecost savings over sapphire.' it also specifically references camera lenses. so is that why the lens is fracturing? maybe its not solid sapphire... it could bejust a thin laminate on top of regular glass because it would be more cost effective...? i realized that in order to really analyzethe lens before posting a video... i need some bigger toys. i headed over to a university, where theyhave an xrf machine.
x-ray fluorescence is a non destructive analyticaltechnique used to determine the composition of materials. remember that this particular machine is onlyqualitative, not quantitative. so it wont tell us the percentage of eachelement, just if that element exists in the specimen. when i test the outside of the lens, we geta huge reading of aluminum oxide., which means that the lens is most definitely sapphireon the exterior. but when i test the inside of the lens, iget no reading for aluminum oxide, but i do get a reading for silicon which is an ingredientof glass.
this means that the underside of the lensis made of; or coated with, glass... but the xrf machine does not tell how thickeach side is. so, in order to find the thickness of eachlayer of the lens, i need an even bigger toy. now, this machine is an electron microscope. costing close to a million dollars, i wishi had one in my basement... but santa keeps on ignoring my letters. either way, in this test, i have broken theactual iphone 7 lens out of the phone, and here we are looking at the cross section ofthe broken lens. this here is the total lens thickness.
and this electron microscope is showing usthe actual elemental make up of the lens. thumbs up for science. the lens was cleaned before analyzing. and this is what we see during the scan. the different colors represent where the differentelements are found in the lens. carbon and silicon are not ingredients ofsapphire. only aluminum oxide. so from this image, we can pretty safely assumethat the sapphire we are looking at is not pure.
there are a pretty hefty amount of contaminants. like the carbon and silicon. remember how my diamond detector tool hada lower reading on the inside of the lens? that's because there is a silicon layer, thatyou can see here, but it is incredibly small in proportion to the rest of the lens, soits pretty much a non issue. i bet that inner layer is more to minimizereflection or something minor because structurally it doesn't seem like it would add any value. the vast portion of the lens is aluminum oxide. the graph here is quantitative, so it is givingus an accurate percentage of elements.
aluminum oxide, carbon, and silicon in thisparticular reading. lets look at another segment. remember this is the exterior, and this isthe interior. and this is the profile of the crack. it has that incredibly thin coating of somethingon the inside. niobium and silicon. â niobium improves the refractive index ofoptical glass, allowing for thinner and lighter lenses, so it looks like that particular elementis intentional. the majority is aluminum oxide, which is whatwe call sapphire, but then we still have quite
a bit of carbon. the main impurity. here is the quantitative graph again. the carbon is still a decent sized chunk. the niobium and silicon are just on that tinyinner layer. now, lets take a look at the elemental analysisof the sapphire crystal on my tissot watch. the only two elements found on the surfacein the scan are aluminum and the oxide. no carbon impurity, also ratios of the tissotsaphire are also very different than apples sapphire.
apple only has a 2 or 3 percent differencebetween the aluminum and oxide. and tissot has almost a 10% difference. now, i am not a chemist, geologist or an engineer,i personally graduated in business. but these numbers sure are interesting betweena lens that fractures and a lens at does fracture and a lens that doesn't. after filming and editing this video, i noticedthat one of mkbhd's most popular videos, which i will link in the video description, is aboutthe prototype sapphire screen of the iphone 6. he came to the independent conclusion thatit scratched at a 7 on mohs scale.
which, if that prototype was indeed a realpiece of apple sapphire, it does match the same recipe that they are currently usingfor their camera lens. makes me wonder: if the 'sapphire' screenprototype, and the current 'sapphire' camera lens, both scratch early... is the 'sapphire'apple watch made with the same weak recipe? and the bigger question: how impure can yoursapphire be and still call it 'sapphire'? in conclusion. just because my results show that the lensscratches earlier than sapphire, doesn't mean its a bad lens. its still scratch resistant, just like glassis, and the pictures are still great.
its just not as scratch resistant as we allthought it was. if you like seeing technology reviewed fromthe inside, hit that subscribe button. my behind the scenes stuff can always be foundon instagram and twitter. @zacksjerryrig thanks a ton for watching! hope to see you around.
