TIPS NO:            244

 

Revision:         

 

Date:                Oct 2004

 

 

 

 

 

 

 

Navigator™ Brown and Gray PolarShades™ Progressive Lens in Standard Plastic Product Specifications.

 

Purpose:
The following is provided for processing Navigator PolarShades progressive lenses in standard plastic.

Characteristics

Navigator Progressive Lens

Refractive Index

1.499

Dispersion Value (Abbe)

58.0

Density

1.32

Polarizing Efficiency

99%

Visible Light Transmittance

16%

UV Blockage

UVB 100%; UVA 99%

Chemical Resistance

Excellent

Machinability                        

Excellent

Rear Surface Coating

Optional

Scratch Resistant

In-Mold RLXPlus®

 

 

 

 

 

 

 

 

 

 

 

 

Unique Semi-Visible Mark: 

 

Blank Size:

78mm diameter blanks decentered 3mm

Effective diameter is 84mm.

Base Curves: 

3.25, 5.00, 7.00

Power range: 

-7.00 to +5.00

Add range:  

1.00 to 3.00 in .25 Diopter steps.

Thicknesses:

We recommend a minimum center thickness of 1.8mm

 

Navigator PolarShades Progressive Lens in Standard Plastic - Dimensions

 

General:
Standard surfacing procedures for CR-39®  progressive lenses should be used with the PolarShades Navigator lens.  If you have questions regarding these lenses, contact Technical Services at 1-800-759-0075

 

Computer Calculation of Rx:

The easiest, most efficient method to calculate and process values for an Rx is to use an existing computer software package that contains Navigator Progressive Lens design data.   If your software does  not include this data, our Technical Services group will be happy to provide the necessary specifications.  Please forward us the contact name and phone number of your software vendor.  If you need a software program for processing lenses, Signet Armorlite has developed a computer program to calculate surfacing data.  This program is available through Signet Armorlite's Technical Services Department.

 

Semi-Visible Markings:

Navigator lens markings have a “+” at the nasal and temporal sides along the 180º axis line. Approximately 3mm below the nasal “+” you will find the “ ” product code.  Approximately  3mm below the temporal “+” you will find the add power of the lens.  These marks can be located by visually inspecting the lens.  Position the lens at arm’s length, preferably in front of an overhead fluorescent light.  Slowly move it away from the edge of the light fixture while looking at the estimated location of the marks along the surface of the lens.  At a given angle of light, the marks will become visible.

 

Removal/Remarking the Temporary Reference Marks:

The Navigator lens markings may be removed by wiping the surface with alcohol or standard lens mark removing solvents.  These marks are designed to withstand all processing procedures.  They provide an easy way to verify the edging accuracy and  can be removed before or after tinting.

 

To remark the lens, locate the semi-visible markings, specifically the “+” symbols engraved along the 180º axis line (See above procedure for locating the semi-visible marks).  Once you have located the semi-visible marks, mark them on the lens and use the Navigator verification mask for the final frame adjustment.

 

Lens Thickness:

The polarizing film is designed to be as near to the front surface of the lens as possible.  The film location moves away from the lens front surface as the add power of the progressive design increases.  Therefore, if desired, it is best to specify a minimum edge thickness depending on the add power.  If your system cannot be set for a minimum edge thickness by add power, you may wish to use a minimum edge thickness of 2.0mm.  The chart below provides recommendations for lens thicknesses by add power.

 

Add powers

1.00 to 1.50

1.75 to 2.25

2.50 to 3.00

Min edge thicknesses

1.6mm

1.8mm

2.0mm

 

We recommend a minimum center thickness of 1.8mm.

 

AR Coating: 

Because lens impact resistance is reduced by AR coatings, we recommend conducting impact tests for lenses AR coated and sold by your lab.   It may be necessary to increase the minimum center thickness in order to meet impact resistance requirements and depends on the types of backside and AR coatings that are applied.  Please call Technical Services at (800) 759-0075 for additional information about coatings and impact resistance.

 

Impact Resistance: 

As a component, lenses of this design have been shown by testing to be capable of being processed to meet applicable impact resistance of FDA Regulations 21 CFR 801.410 and ANSI Z80.1. Conformance to this standard is the responsibility of all subsequent processors. Impact resistant lenses are not unbreakable. Obviously damaged lenses should be replaced immediately.

 

Fitting Recommendations:

Position the fitting cross either at the center or bottom of the pupil.

 

Frame Requirements:

The frame must provide approximately 15mm of distance above the fitting cross.  The minimum fitting height is dependent on the frame shape and decentration required.  The desired result is when all or the majority of the near vision circle falls inside the frame.

 

Tinting:

We do not recommend tinting PolarShades lenses

 

CR-39 is a registered trademark of PPG.

RLXPlus is a registered trademark, Navigator and PolarShades are trademarks of Signet Armorlite, Inc.

 

Navigator PolarShades in Standard Plastic

Base Curve Selection Chart