How does a varifocal work on a contact lense?
With the glasse you move your eye up and down to select the focus distance. Up futher away and vice versa
If its stuck to your eye ball.....
I tried vari focal once, felt sick and kept jabbing my toes.
Glasses on the bike
- Thread starter RickSkye
- Start date
With the glasse you move your eye up and down to select the focus distance. Up futher away and vice versa
If its stuck to your eye ball.....
I tried vari focal once, felt sick and kept jabbing my toes.
soho
Well-Known Member
I do have a pair of Bifocals which I have tried using in the car and on the bike, very good ,but for all the good they are worth it's easy to be suddenly looking through the wrong part of the glass. Which at speed can be a bit more dodgy than just checking your belly button in the bathroom ! I barely ever wear them now, as I use are readers , intermediates and distance individually . Bit of a constant fiddle but safer (for me at least), Next time I go for an eye check they'll probably give me a brail test and I'll come away with a prescription for a pair of gloves ? !
Last edited:
austin
Well-Known Member
For varifocals I think it is done by concentric rings of different power and your brain works out/merges which bits of detail it needs with the result being sharp vision as all distances. In fact I just googled it and that is one of the ways it's done. Bifocal and Multifocal Contact Lenses And that link confirms you can get bifocals in contact lenses - again concentric rings, or weighted.
Varifocal specs - yes they can take a bit of getting used to, although from the way concentric varifocal contacts work it shouldn't be an issue for them as long as your brain can cope. I found three things difficult when I first got varifocals: looking down something like a flight of stairs or at your feet - you are using the reading bit of the lens when you really need the distance bit, so stuff can be a bit blurry. Getting used to the slightly swimmy effect as you change focal length going from near to middle to distance focus and vice-versa. Finally varifocals have a sweet spot that should be directly in front of you. Basically you need to look directly at the things you want in sharp focus. The size of the sweet spot depends on the quality (and therefore price) of the lens and how good your optician is at fitting your lenses into your frames and your frames to your face. Things towards the corner of your eye will not be in sharp focus, although that's only not pin sharp i.e. you can still see things just not in sharp focus, e.g. a life-saver is likely not to be pin sharp but you will still see stuff out the corner of your eye. Have a look at websites from the lens manufacturers - Zeiss is good - for more information. Here's a starter: ZEISS Progressive lenses | ZEISS United Kingdom
I gave up very quickly with contacts. I could see distance but not read my phone, so on the bike I could not see the sat nav or even the speedo. Neither the concentric rings or one lens for distance one for short were thought of as sensible options so I'm back to glasses.
I am going to optitians on wed to see what they can offer, but it sounds like they won't do what i want.
Just been to optitians. He says my particular prescription would be challenging for staight contact lenses, anything with more that one focal length, he would not waste my money.
Now thinking about how to make heated glasses......
Or fit a blower to the helmet [emoji28][emoji28][emoji28][emoji28]
Now thinking about how to make heated glasses......
Or fit a blower to the helmet [emoji28][emoji28][emoji28][emoji28]
Same here. Gonna look again at fog masks.
hotbulb
Active Member
I'm lucky that I get on pretty well with varifocal glasses, and am happy riding with them (just need to take extra care with "shoulder checks" etc as peripheral vision is not really in focus). I rarely have problems with the glasses steaming-up, but opening the visor a crack does the trick. Perhaps some lens materials are better than others - these are fairly basic cheapish glasses (Specsavers?) .... both Shark helmets I use have pretty good anti-fog treatment. But my new HJC helmet has a pinlock insert .... never tried one before... and it's a revelation! I'll certainly want one in any future helmet I buy.
Lowflyer
Well-Known Member
Climbingnut
New Member
I wear these quiksilver ones. The arms are basically straight (as in they don’t bend around the ear) but malleable enough that they bend around my head inside the helmet. A doddle to put on and take off.
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MooN
Active Member
I have never really experienced the problem, despite riding pretty much in all weathers and wearig glasses for riding for a number of years now, I sometimes have to crack open the visor for some airflow but otherwise...
on the subjest of polaroid lenses, I tried thm once but could only see all the stress lines in the visor in a sort of purple " aurora" which made riding impossible. Someting to do with the visor being stressed lexan ( according to my opthalmologist) and the way polarisation works... never tried since. Interesting that you don't have that prob Soho.
So how do you get your prescription onto them?I wear these quiksilver ones. The arms are basically straight (as in they don’t bend around the ear) but malleable enough that they bend around my head inside the helmet. A doddle to put on and take off.
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