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Do
all hongtai sunlens products have UVprotection? |
| |
Yes,all hongtai sunlens products can meet
the UV standards.
If you would like further details and lens specifics,please
contact us |
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Does Hongtai
have the FDA number? |
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Yes,the number is 9071021 |
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To what standards
are sunlens measured? |
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The sunlens must meet the requirements of
the standards as below
European Sandard--EN:1836.1997
(Form)
American Standard--ANSI
Z80.3,2001(Form)
Australian Standard！AS/NZS
1067.2003(Form) |
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How to obain maximum protection
form a solar filter? |
| |
One should
Eliminate Ultraviolet radiation up to 400nm
Provide protection from blue light while maintaining the natural
perception of colors
Select wide,wrap around sunglass frames,or with side protection
Select a degree of protection according to the light conditions |
| |
What is Categories? |
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The explanatory note that come with the
pair of sunglasses also lists the category of the lens and
contain instruction for use.This means that any pair of sunglasses
acquired is indicated for only some but not all used.In other
words,there is a different pair of sunglasses for each situation.The quantity
of the light that reaches the eyes can be modulated and filtered
by lenses that offer different degrees of light transmission
and therefore different uses.
The degree of light transmission of a lens represents its
capacity to diminish
to greater or lesser degree the quantity of light that reaches
the eyes,and
this suggests the most appropriate use under each condition
of solar
irradiation.At the seaside,for examples,a category 3 filter
can be uses,while
Category 2 filter are sufficient for driving or city use.Under
extreme light
conditions,such as in the mountains,the snow field,a Ctegory
4 filter is
required.
Filter Categories:
| |
|
|
|
| 0 |
80%-100% |
Comfort, fashion
for tie-in |
None |
| 1 |
43%-80% |
Weak sunlight |
Not recommended
for driving and road use in general after dark |
2 |
18%-43% |
Average sunlight |
Not recommended
for driving and road use in generalafter dark |
| 3 |
8%-18% |
Strong sunlight |
Not recommended
for driving (and road use in general) after dark |
| 4 |
3%-8% |
Exceptionally
strong sunlight |
Not recommended for
driving (and road use in general)
Important:a dark lens doesn't necessarily always provide
complete protection!Make sure to check the quality and
origin of the pair of sunglasses to make sure it guarantees
the right protection. |
|
| Q: |
Why do 8B and
higher wrapped frames need decentered lenses? |
| A: |
The higher wrapped frames require a lens
where the optical center is offset (decentered) to accommodate
for off axis and prismatic errors that always occurring the
highly curve .In order to meet International Standards for optical
performance,decentered lenses must be used in the wrapped frames. |
