The Classroom

Harbor Optical is pleased to offer you some additional tools and information to help improve your knowledge base.  Here you can find the most recent progressive availability charts along with a plethora of technical articles we will continue to add to and update.

Progressive Availability Charts

As an independent and unbiased lab, we have complied a comprehensive list of progressive lenses.  We encourage you to download and print this chart for use as a "cheat sheet".  Full size wall charts are also available from the lab, or from your sales rep.  Please contact us and we will be happy to send one to you.  This chart is in Adobe PDF format, and requires a copy of Adobe Reader, available here.

To download your copy of the "How Low Can You Go" progressive availability chart, click here.

Your basic guide to occupational lenses

Occupational lens sales have sharply increased over the past few years.  To help you capitalize on this opportunity to fulfill your patients' needs as well as potentially increase second pair sales, we have put together a basic rundown explaining what occupational lenses are, what the major distinctions are between them, and a brief FAQ section that we hopes answer some of the questions you might have.

Occupational lenses are a variation of the standard progressive designed lens that sacrifice the distance prescription for an increase in the intermediate power area, while still offering a useable reading area.  Designed for use in an occupational or office setting, these lenses help improve vision at or near arm's length, such as reading papers or working with a computer.  They also feature a large reading area for standard up-close reading, such as books and charts.  These lenses offer little to no distance prescription, and are not designed to be used as a primary or daily-use pair of lenses.  Many of the major lens manufacturers have introduced occupational lenses to the market, and we have included a basic rundown of the below, highlighting some of the differences and unique characteristics between them.

SHAMIR OFFICE

1. TOTAL READING POWER RANGE IS BETWEEN -6.00 D AND +6.00 D   (combined sum of sphere power and add power)  -3.00 to +6.00 in poly CYL TO 4.0D
2. PROVIDE FULL RX BOTH DISTANCE AND NEAR
3. PROVIDE MONOCULAR  DISTANCE P. D.
4. FITTING CROSS IN FRONT  OF PUPIL
5. MINIMUM OF 13mm FROM THE PUPIL TO UPPER RIM
6. MINIMUM OF 16mm FROM THE PUPIL TO THE LOWER RIM
7. MINIMUM B MEASUREMENT OF 29 mm
8. ***Office 175 is no longer available in polycarbonate material.  All other Office lenses are available in polycarbonate.

ZEISS BUSINESS

1. NEAR POWER  +6.50d TO -5.00d
2. CYL UP TO -4.00d ( TOTAL POWER NOT TO EXCEED -5 d)
3. Prism up to 3.0D
4. MINIMUM FITTING HEIGHT  16mm
5. AT THE FITTING CROSS APPROX 50% OF DECREASE, FULL DECREASE REACHED AT 12mm ABOVE FITTING CROSS
6. MONOCULAR DISTANCE PD
7. MINIMUM FITTING HEIGHT 16mm FROM CENTER OF PUPIL TO DEEPEST POINT OF FRAME
8. MINIMUM OF 14mm ABOVE FITTING CROSS TO UPPER RIM
9. MINIMUM B measurement of 30mm

ZEISS GRADAL RD

1. POWER RANGE -6.00d TO +6.00d ,CYL OUT TO-4.00 ADDS 1.00d TO 3.00d
2. ORDER DISTANCE AND NEAR AS USUAL
3. LAB MODIFIES RX TO INDOOR CORRECTION CHANGE +.50 IN THE DISTANCE -.50 IN NEAR

ESSILOR INTERVIEW

1. LENS WILL DECREASE 0.80d STARTING 4mm BELOW INVERTED FITTING CROSS CONTINUING TO 6mm ABOVE GEOMETRIC CENTER OF LENS
2. MEASURE FITTING HEIGHT TO LOWER LID
3. TAKE MONOCULAR NEAR PD's
4. ORDER NEAR PRESCRIPTION
5. RANGE -2.0 TO +4.0 TO -2.0 CYL
6. BEST SUITED FOR PRESBYOPES WITH LITTLE OR NO DISTANCE CORRECTION
7. FRAME SELECTION - USE FULL FRAME WITH ATLEAST A 34mm B MEASUREMENT

PRIO BROWSER

1. RANGE -5.00d TO +6.50d TOTAL NEAR CYLS TO-4.00d
2. TWO POWER SHIFTS 1.00AND 1.50 DECREASE IN PLUS POWER FROM READING AREA TO TOP OF LENS
3. FITTING CROSS AT PUPIL CENTER
4. MONOCULAR DISTANCE PD
5. MINIMUM FRAME B OF 29mm
6. SEG HEIGHT OF 16mm
7. 13mm TO TOP OF LENS
8. VERIFY IN READING ONLY

PRIO COMPUTER LENS

1. RANGE -3.00d TO +6.00d TOTAL NEAR POWER TO -4.00d CYL
2. POWER SHIFTS 0.75 1.25 1.75
3. ABOUT 50% OF POWER SHIFT AT FITTING CROSS
4. FITTING CROSS AT PUPIL CENTER
5. MONOCULAR DISTANCE PD's
6. MINIMUM FRAME PD OF 29mm
7. SEG HEIGHT OF 16mm
8. 13mmTO TOP OF FRAME
9. VERIFY IN READING ONLY

SOLA ACCESS

1. POWER RANGE -6.00d TO +4.00d
2. CYL TO -4.00d
3. POWER SHIFTS 0.75 FOR 1.50 ADD OR LESS 1.25 FOR 1.75 OR GREATER
4. FIT AS SV AT MIDLINE WITH PUPIL WITHIN 5mm OF PUPIL CENTER
5. MONOCULAR NEAR PD's
6. FRAME MINIMUM B OF 29mm
7. VERIFY NEAR ONLY BELOW DASHED ARCH

SOLA CONTINUUM

1. POWER RANGE -2.00d TO +4.50d OUT TO -4.0 CYL
2. POWER SHIFT 1.00
3. FIT MIDLINE WITH PUPIL WITHIN 5mm OF PUPIL CENTER
4. MONOCULAR NEAR PD's
5. FRAME MINIMUM B OF 29mm
6. VERIFY NEAR ONLY AT CIRCLE

Because occupational lenses are such a unique design, many opticians and dispensers are unsure as to how to measure or fit these lenses.  To help answer those questions, we've created a brief FAQ section to address some of the more common questions we hear.

Q. How do you measure for occupational lenses?

A. As a rule of thumb, you measure for occupational lenses much the same way you measure for standard progressives. In fact, we ask that you provide us with a standard progressive script and an occupational lens choice so that we can do the script conversion here.  The most important thing to remember when fitting for an occupational lens is that each style has specific frame height requirements, so make sure you adhere to them. This means that once they decide on an occupational lens, there frame choices must be limited to ones that fit the lens guidelines.  While it is important under normal circumstances to fit the frame to the lens (instead of picking a lens to fit a frame), it is of the utmost importance with occupational lenses. Otherwise, lens performance stands to be greatly compromised.

Q. Why are occupational lenses mostly only available in CR39?  Why not trivex, or even poly?

A. The cost to develop molds for a new lens are very prohibitive.  And, as occupational lenses tend to be taken on and off repeatedly throughout the day, they are not well suited to grooved or drill mounting styles as they put more stress on the lens than a full bevel mounting.  Seeing as how that is the primary reason most optometrists or dispensers would select one of those materials, the lens manufacturers have chosen not to introduce their occupational lenses in those materials.  If you would like to see an occupational lens made available in trivex or polycarbonate, the best thing to do is contact the sales representative for the manufacturer of your choice.

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