TABLE OF CONTENTS
Site Navigation Features
Hyperlinks - Are words in the text of a page, chart or table that are clickable links to other pages. Usually any words that
are a different color will be hyperlinks. Point to them and they change to a hand - like this. When you are viewing a page showing a list of search results, often the lens name will be a
hyperlink to either a Quick Reference Guide or Details page. Read the introduction at the beginning of each search results
page for assistance in identifying the use of hyperlinks on that page.
Quick Reference Charts - Show brief, pertinent information of specialty lens groups such as Freeform/Digitally Surfaced
or Near Variable Focus lenses in a table for comparison purposes to other brands.
Manufacturers -
Each time a manufacturers name is displayed on this
website, it will be a hyperlink that will take you
to another website that is NOT part of TheLensGuru.com
website. The new site will open in another window
or tab so when you close your
browser you will be back here to this site.
Printing Centration Charts
If there is an available Centration Chart for the lens you are researching, you will see
an icon labeled "Click to View a Printable Centration Chart" in the Quick Reference Guide
or Details page. Charts are presented in the .pdf format for easy viewing, saving and printing.
To view .pdf documents you need a program such as Adobe Reader or Foxit Reader, both available
as free downloads.
**To print Centration Charts accurately you need to follow a few simple but important rules.
- Click the icon to open the chart.
- Click File, then Print.
- In the Print dialogue box look for the label Page Scaling:
- Be sure that either None or something like 100% is chosen
or your cutout and centration measurements may not be accurate.
- Click OK or Print
- Use a ruler to measure anything verifiable on the chart once printed. For instance, if
the lens blank is marked at 75mm, measure across the center and make sure it measures exactly
75mm. If not, repeat the above steps.
Search Options
Dropdown Boxes - Along the top of each page are dropdown boxes labeled "All Brands", "Freeform", "Near
Variable Focus" etc. which contain
lists of lenses in The Lens Guru database grouped by category. Choose a lens brand in the
list to access the Quick Reference Guide displaying the materials available and basic data
such as minimum fitting height and power ranges.
Search Database - A link is provided in the navigation along the left of each page that will take you to the
Search Database Page where you can search the database via simple to use dropdown boxes by selecting the specifics you need
for your customer. You can choose from as many lists as you like to pinpoint or "drill down" to the best lens or
lenses available.
PAL Identifier Images - Are a page of PAL Identifier images where each image shown is also a clickable hyperlink to the
Quick Reference Guide.
Searching the Database
The Search Database page provides you with a powerful yet easy to use search engine that allow you
to "drill down" to the lens or lenses that best meet your requirements. Designed with easy to use
dropdown lists and buttons, searching The Lens Guru database is simple and powerful if you follow a
few simple guidelines. In general, you should always choose the Material,
Minimum Seg Height and Color (clear is selected by default).
Read below for a detailed description of each search option.
Lens Design Type
The Lens Guru database currently features two lens design types:
- Progressive Addition Lenses-Includes variable focal lenses with the full distance and
near Rx incorporated into an invisible, progressive design. This option is chosen by default
- Near Variable Focus Lenses-Includes invisible variable focus lenses with focal ranges usually ranging
from intermediate to near with no usable distance correction.
*Tip - It's best to choose one or the other. You will probably never need to search both for a single solution
but it is available.
Design Technology
This describes manufacturing processes, not lens design. I have chosen to create three categories
of lens design; Standard, Freeform/Digitally Surfaced and Digital Mold.
- Standard - Lenses manufactured by traditional
methods. The front surface is typically cast from
a ceramic mold and incorporates the PAL design.
- Freeform/Digitally Surfaced - Lenses manufactured
with Computer Numeric Controlled (CNC) surfacing
technology, sometimes generically refered to as 'freeform'
surfacing. Typically the front surface is spherical
with the PAL design and Rx
freeform generated onto the back of the lens.
- Digital Mold - Refers to a class of lens
that is some of both old and new technologies. Typically
these lenses have a front side cast from a digitally
cut glass mold (freeform/digital technology) with
the backside surfaced by traditional 2-axis generators
(old school). The digitally cut glass molds provide
greater accuracy
and reproducibility of the PAL and front surface design.
It is difficult to assess which lenses fall into
this category as literature can be vague or misleading.
There may be many lenses that could fall into this
category
that aren't listed correctly here yet as many manufacturers
are turning to this as their standard on front surface
PALs. I think most of us would like to know when
a lens is designed this way as opposed to either
of the above so
we know exactly what we are working with, so I have
included a separate category.
Material
- Glass - Includes all indexes
- Plastic/Standard - With index of 1.49 or 1.50
- Plastic/Mid Index - Index from 1.54 to 1.58, not including Trivex
- Plastic/High Index - 1.59 and above, not including Polycarbonate
- Polycarbonate
- Spectralite - SOLA proprietary mid index material
- Trivex - includes the brandnames Aris, Trilogy and Phoenix
By Index of Refraction
You can choose to search by a specific index of refraction instead of material. If you make
a choice from this box, the Material box will become unavailable for selection. You can
choose one of two ways:
- Within A Range - Refine search to a specific range of indexes.
- By Minimum Index - Refine search to lenses of a minimum index of
refraction. This will include lenses with an index of refraction equal to and
greater than the index chosen.
Minimum Fitting Height
This is one of the most critical components of any search so be sure to include it in
your search.
Lens Color
Clear is chosen as the default so be sure to change it if you are looking
for photochromic, polarized or tinted lens.
Photochromic
When searching for Photochromic lenses
be sure to choose the color to eliminate search results that include lenses in colors you don't need.
This will include all brandname photochromics.
Polarized
Polarized lenses will always be sun lenses so be sure to choose a color also.
High/Low Add Powers
Allows you to refine your search to lenses available with add powers above
and below the normal +1.00 to +3.00 available in almost every lens.
High/Low Basecurves
Allow you to refine your search to lenses flatter than +2.00D and and
steeper than +6.00D.
VSP
Vision Service Plan (VSP) is a prolific US Vision Care Plan. If you don't
know what it is, you don't need it so you will get more relevent results
if you leave it blank. Otherwise, it's a nifty way to save time for those
working in offices that take VSP.
General Guidelines
Try to keep from doing searches that are too broad. For instance if you simply searched for all
progressive lenses made in Standard Plastic that fit 18 high you will have a very high number of
results. In general, you should always choose Material, Minimum Seg Height, Color (Clear is
chosen by default) and of course Photochromic or Polarized if applicable.
If you do not want photochromic or polarized lenses you do not need to
click the box and choose 'No', you may leave them blank.
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