BACK SURFACE PROGRESSIVE

BACK SURFACE PROGRESSIVE

TOKAI

BS SERIES

TOKAI BS SERIES

1) Back surface progressive

2) Back surface aspheric

3) Personal Design System

a. Selectable progressive corridor

b. Selectable front base curve

c. Requestable inset amount(Flexible inset amount)

1) Back surface progressive

2) Back surface aspheric

3) Progressive corridor 13 / 15

Custom-made back surface progressive

BS-C UVBack surface progressive

BS-13 UV

BS-15 UV

The design points of BS seriesThe design points of BS series

1. Improvement in basic ophthalmic performance1. Improvement in basic ophthalmic performance

2. Correspondence to individuals (Personal Design System) 2. Correspondence to individuals (Personal Design System)

TOKAI

BS SERIES

BACK SURFACE PROGRESSIVE DESIGN

Designing an ideal surface , which combines dioptoric,

aspheric and progressive surface

Improvement in Improvement in Basic performanceBasic performance

Assuming a progressive and aspheric surface

Front surface aspheric design

-3.50D

Fixed aspheric amount

-4.00D-4.50D

BACK SURFACE ASPHERIC DESIGNImprovement in Improvement in

Basic performanceBasic performance

-3.50D

Ideal aspheric amount for each

dioptor

-4.00D-4.50D

TOKAI BS series



Certain aspheric amount at each axis

-4.50D

-3.50D



Lower

BS series

Conventional progressive

Higher

15 KINDS OF FRONT BASE CURVEImprovement in Improvement in


BACK SURFACE PROGRESSIVE + ASPHERIC

About 30% About 35%

Thinner and Lighter

IMPROVEMENT IN BASIC IMPROVEMENT IN BASIC OPHTHALMIC PERFORMANCEOPHTHALMIC PERFORMANCE

Increasing the vision field

Reducing floating and distortions

(S-6.00 ADD2.00 Comparison in Tokai)

Ordinary

BS series

PERSONAL DESIGN SYSTEM (P.D.S)

*Entrustment is allowed

Correspondence Correspondence to individualto individual

Corresponding to each wearer’s individual eyes

1.Progressive corridor Selectable from corridor lengths

of 11, 13, 15 or 17mm2. Front base

curve Selectable front base curve from lower or higher

3. Inset Requestable inset 0.0 to 5.0mm, 0.1mm steps

Corridor Length

SelectableE

ntrustment

◎◎

使用目的・累進経験・年齢・度数情報

◎

静的ライフスタイル・ｽﾀｲﾘｯｼｭﾌﾚｰﾑ◎

Active life style, mitigated floating and distortion

Considering the shift of requirements

Age Experience


CORRIDOR LENGTH

11mm

◎

13mm

◎

15mm

◎

17mm

◎


*Selecting from 13mm or 15mm automatically

*Determining appropriate corridor length, considering far dioptor and addition

Considering the shift of requirements

Age of wearer

Experience of wearing progressive

CORRIDOR LENGTHCorrespondence Correspondence

to individualto individual

Front base curve

SelectableE

ntrustment

　 Standard　　 Higher　

Lower

Ophthalmic performance

CosmeticFrame shape


Optimized based curveAdjusting

front curve

*Request a Higher or Lower

*Two steps higher or lower taking a balance of R & L base curves

FRONT BASE CURVECorrespondence Correspondence


LowerStandard

Higher

Higher

Lower

Negative Positive

The lens is thin.Same distance from lens to face

= Small deformation

The lens is thick.Same distance from eye to lens

= Small distortion

FRONT BASE CURVE

Standard base curve

Lower

Higher

Increasingcosmetic performance

Increasingophthalmic performance


Inset

1) Specific inset 0.0mm to 5.0mm in 0.1mm step, at Right and Left2) Far PD and selecting reading distance from 33, 36 or 40cm

Calculated the inset amount based on

Far dioptor, Addition and Front base curve(Far PD 62mm and Reading distance 36cm)

Inset amount is printed on envelop

Requestabl

eE

ntrustment


Far and Near EP

Corridor length

Flexible inset design

Far EP

Near EP

Inset


Prism effect = Change of PDNaked eye sight

Prism effected eye sight

Object

Reading distance

Far PD

Flexible inset designCorrespondence Correspondence


Influence of Far dioptorInfluence of Far dioptor

1. 5

2. 0

2. 5

3. 0

3. 5

- 15. 00

- 10. 00

- 5. 00 0. 00 5. 00 10. 00Dioptor

75mm70mm65mm60mm

2.5mm



Inset(mm

)

Model of calculated ray tracingModel of calculated ray tracing

Vertex distance 　12mm Tilt angle: 10 degrees

Progressive corridor

Horizontal glance line

Reading glance line



1. 5

2. 0

2. 5

3. 0

8 9 10 11 12 13 14 15 16

Vertex distance (mm)

Influence of vertex distanceInfluence of vertex distance



Inset(mm

)

Transition by tilt angleTransition by tilt angle

1. 5

2. 0

2. 5

3. 0

0 5 10 15 20

Tilt angle (degree)

Flexible inset design

Inset(mm

)


Difference of Inset amount by PD for Far

Object

Requesting a specific Inset amountRequesting a specific Inset amount

Long PD

Large Inset mount

Difference of Inset amount by PD for Far

Object


Short PD

Small Inset amount

Difference of Inset amount by Reading distance

Object


Reading distance

Inset amount

Difference of Inset amount by Reading distance

Object

Short Reading distance


Large Inset amount


1. 5

2. 0

2. 5

3. 0

33 34 35 36 37 38 39 40

Reading distance (cm)

PD 70mm

PD 62mm

PD 54mm

Difference of Far PD & Reading distance

Long PD

Short PD

Inset(mm

)

Suitable front base curve

Selectable progressive corridor

Selectable front base curve

Requestable inset amount

Flexible inset amount

P.D.S

Optimum aspheric amount

Improvement in basic performance

OPTIMIZATIONOPTIMIZATION

FLEXIBILITYFLEXIBILITYTOKAI BS SERIES

TOKAI PROGRESSIVE LINE-UP

BS-C UV

BS-15 UV & BS-13 UV 1.70-15

PROGRESSIVE UV

1.60/42-15 PROGRESSIVE UV

1.50-15 PROGRESSIVE

1.60/42-13 PROGRESSIVE UV

1.50-13 PROGRESSIVE

GR

AD

E

Far vision All-round Near vision

1.70-13 PROGRESSIVE UV

Documents

BACK SURFACE PROGRESSIVE