TIPS NO: 232A
Revision:
Date: July, 2006

NAVIGATOR SHORT^® Short Corridor Progressive Lens in PolyClear^® Product Specifications and Fitting Guide.

Product Specifications and Fitting Guide

PURPOSE: The following is provided for fitting and processing NAVIGATOR SHORT PolyClear Progressive Lenses.

Characteristics	NAVIGATOR SHORT IN POLYCLEAR
Refractive Index	1.586 ref d
Dispersion Value (Abbe)	36
Density	1.20
Chemical Resisitance	Fair (avoid all solvents except IPA)
Machinability	Good
Rear Surface Coating	Required
UV Transmission cutoff	380 nm

UNIQUE SEMI-VISIBLE MARK:
BLANK SIZE: 78mm diameter blanks decentered 2.5mm. Effective diameter is 83mm
BASE CURVES: 2.00, 4.50, 5.75, 7.25
POWER RANGE: -11.00 TO +5.00
ADD powers: 1.00 to 3.00 in .25 Diopter steps.
THICKNESS: We recommend a minimum center thickness of 1.5mm. To ensure proper frame retention, low power lenses may require greater thickness.

NAVIGATOR SHORT PolyClear Progressive Lens - DIMENSIONS

Nominal Curve	True Curve	Radius mm	SAG at 50mm	Nominal Concave	Edge Thickness	Center Thickness
2.00	1.97	269.036	1.16	6.00	13.4	7.7
4.50	4.58	115.721	2.73	6.00	8.9	7.6
5.75	5.78	91.696	3.47	6.00	7.4	8.4
7.25	7.21	73.509	4.38	6.00	8.4	12.7

GENERAL:
Processing of the Navigator Short PolyClear lens is similar to that of standard resin with a few exceptions. Generator, edger wheels and two-step fining pads designed for polycarbonate material must be used.

If you have questions on processing the Navigator Short PolyClear lenses, please contact our Technical Services department at 1-800-759-0075..

SEMI-VISIBLE MARKINGS
Navigator Short Lens markings have a “+” at the nasal and temporal sides along the 180º axis line as well as the marking . 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 the lens away from the edge of the light fixture while looking at the estimated location of the marks along the surface of the lens. The marks will become visible at a given angle of light.

REMOVAL/REMARKING THE TEMPORARY REFERENCE MARKS
The Navigator Short Lens markings may be removed by wiping the surface with alcohol. If AR coating the lens, make sure all residue is removed by wiping the area a second time. Never use acetone on PolyClear lenses.

To re-mark the lens, first 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 markings, dot them on the lens and use the Navigator Short verification chart for the final re-marking.

FINING AND POLISHING:
Processing the Navigator Short Lens is the same as processing other polycarbonate lenses. Safety bevel the lens before fining to allow the slurry smoother access along the lens surface. Large lap tools (at least 3 inch) should be used and allowance made for approximately 0.3mm of stock removal. Perform a stock removal test, using your process to most accurately establish the correct surfacing thickness allowance. We strongly recommend fining pads with eight or more petals be used for curves over 9.00 diopters. This can prevent aberrations and score lines.

EDGING:
Layout for edging should be done in reference to the fitting cross located 2.0mm above the MRP. The fitting cross is placed at the point of the specified segment height and monocular PD..

ABRASION RESISTANCE COATINGS:
The front surface of the KODAK PROGRESSIVE 1.56 EVOCLEAR LENS includes the superior protection of the RLXPlus® non-tintable coating. The uncoated rear surface of the lens provides adequate durability for normal use. Therefore, a backside coating is not required.

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 requirements of FDA regulation 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.

AR COATING:
Multi-layer AR coatings can be applied to Navigator Short Lenses. Be sure that your AR coating is compatible with your backside coating. Include impact testing 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. Please call Technical Services at 800-759-0075 for additional information about coatings and impact resistance..

TINTING:
Neither PolyClear material nor the front surface coating used on this lens will absorb tint. Therefore, in order to tint, a tintable backside coating must be applied. Conventional hard resin tints are acceptable. Neutralize by using only products designed for polycarbonate. Standard neutralizers will damage the lens..

FITTING AND FRAME SELECTION:
Our minimum fitting height (sometimes called the segment height) is 17mm, based on the 12mm corridor length. The measurement includes 2mm above the reference dot where the fitting cross is marked, as well as 3mm of clear area below the full addition location. Minimum fitting height values are completely Rx and frame dependent. The frame shape and patient’s monocular PDs will affect this minimum fitting height, which is measured from the lowest point of the frame and not the lowest point of the frame where the reading area falls. Illustration 1 shows that the near zone may not fall inside the frame for certain frame and monocular PD requirements.

If a small portion of the critical optical area is outside the frame, discuss with the patient the optical compromise that will occur if this frame is used.

Kodak is a trademark of Eastman Kodak Company, used under license by Signet Armorlite, Inc.