Laser Cleaving of Optical Laser Cleaving of Optical ConnectorsConnectors

Didi Hachnochi

VP Engineering & R&D

Duane Dinkel

President

Sagitta Incorporated

655-H Fairview Road

Simpsonville, SC 29680

IntroductionIntroduction

• The Problems Mechanical cleaving – operator and tool-dependent quality (hand-

scribe, sand-blasting, etc.)

Epoxy Bead size – operator and process-dependent quality

Polishing – sub-optimal initial conditions (overuse of consumables;

costly)

Connector/Fiber-specific challenges – MT, Large OD fiber, SMA’s, etc.

Compromised First Pass Yield, Throughput, Quality, and Cost!

• The Solution Laser Cleaving (integrated denubbing and epoxy removal)

• Results

• Future Technologies

• Conclusion

Connector Termination ProcessConnector Termination Process

Cut toLength

Strip & Clean

AssemblyI

InsertionInto ferrule

EpoxyApplication

EpoxyCure

FiberCleave

Air Polish“Denub”

EpoxyRemoval

PolishSequence

AssemblyII

CleanEndface

VisualInspection

GeometryInspection

OpticalInspection

LabelAnd Pack

Uncleaved Connector TipUncleaved Connector Tip

CeramicFerrule

Fiber“Stinger”

EpoxyBead

5.0 – 15.0mm

CeramicFerrule

Fiber“Stinger”

EpoxyBead

5-15 mm

300-1200um

Manual Cleave ProcessManual Cleave Process

Epoxy Bead

Before After

Ferrule

Fiber

Hand Scribing ToolApply Torsion

Epoxy Bead

Before After

Ferrule

Fiber

Hand Scribing ToolApply Torsion

Mechanical techniques represent > 90% of the industryMechanical techniques represent > 90% of the industry

Hand Polish Process – “Denubbing”Hand Polish Process – “Denubbing”

Hand polishing can consume up to 30 sec per end Hand polishing can consume up to 30 sec per end

After

Fiber Stub & Epoxy Bead

Before

Coarse Hand Polishing Material

– 1000um300 –

Fiber Stub & Epoxy Bead

Coarse Hand Polishing Material

300 – 1200 um 300 – 500 um

Manual Cleave – The ProblemsManual Cleave – The Problems

• Variable Epoxy Bead Size Polishing process variable

Requires hand polish to remove

• Variable “Stinger” Length Extra polishing step

Epoxy Bead Size RangeHeight: 300 - 1200umVolume: 0.02 – 0.05 mm3

Cleaved Fiber Range300 – 500um

• Poor Cleave = Bad Endface

Yield (and quality) problem ⇨ reworks!

Core cracks

Endface chips

Laser Cleaver AnimationLaser Cleaver Animation

Laser Cleaving PrincipalLaser Cleaving Principal

CeramicFerrule

Fiber“Stinger”

EpoxyBead

300 – 1200um

5.0 – 15.0mm

From Curing

80 – 120um

Into Polishing

Focused CO2 beam spot passes thru fiber and epoxy

Combines Cleaving + Denubbing + Epoxy RemovalCombines Cleaving + Denubbing + Epoxy Removal

Simplex Connector Before/After CleaveSimplex Connector Before/After Cleave

Small epoxy

bead

Large epoxy bead

Before Cleave

Hand Cleave Bellow epoxy!

Laser CleaveFiber stub & residual epoxy <

100μ

After Laser

Cleave

Cleave Height Control

-30

-20

-10

0

10

20

30

0 20 40 60 80 100

Sample #

Pro

tru

sio

n V

aria

tio

n,

um

Field Performance - SimplexField Performance - Simplex

USL

TGT

LSL

Cleave Height Reproducibility

Limits must be sufficient to eliminate polishing steps Limits must be sufficient to eliminate polishing steps

MT Connector Cleaving ProgressMT Connector Cleaving Progress

FerruleEpoxy

12 Fibers

Before

After 4 cycles

After 2 cycles

Field Performance - MTPField Performance - MTP

Maximum fiber variation < 20um

Demonstrated ability to remove 20mm3 (5mm x 2mm x 2mm) of epoxy

bead

Cleave height adjustable from 50um

Only constraint is in molded ferrule tolerance (specified at +/- 50um)

Laser Cleaving ImplementationLaser Cleaving Implementation

• Laser safety compliance

• Ergonomics

• Ferrule size (1.25mm vs. 2.5mm vs. MT, etc.)

• Fiber type – SM vs. MM

• Process flow

• Violation of intellectual property

Quality Benefits of Laser CleavingQuality Benefits of Laser Cleaving

• Eliminates operator and tool dependent cleave quality

• Simplifies the polishing process & removes interdependencies

• Eliminates cleave related multimode fiber “core cracking”

• Improves connector reliability - laser “tempers/anneals” fiber endface relieving inherent fiber stresses

Removes up-stream variability

“Levels the process playing field”Removes up-stream variability

“Levels the process playing field”

Cost Benefits of Laser CleavingCost Benefits of Laser Cleaving

• Reduces consumable costs Minimizes abrasive consumable cost (1-2 polishing

operations eliminated)

Eliminates scribe blade wear-out

• Higher yields • Reduces headcount (or increases throughput)

Combines scribing + denubbing + epoxy removalCombines scribing + denubbing + epoxy removal

Cost Benefits of Laser CleavingCost Benefits of Laser Cleaving

Labor ⇩

Cost of Consumables ⇩(abrasive films, scribes, etc.)

Yields ⇧

COGS reduces by 5 – 10%

(Shaving $50M annually out of industry costs)COGS reduces by 5 – 10%

(Shaving $50M annually out of industry costs)

  Manual Laser Cleaving

  BOM CoC L&O Total BOM CoC L&O Total Savings, $/end

SM Low-Volume                  

US (325K ends) $1.13 $0.13 $1.85 $3.17 $1.13 $0.11 $1.51 $2.83 $0.33

MX (650K ends) $1.13 $0.13 $0.46 $1.75 $1.13 $0.11 $0.37 $1.65 $0.10

China (950K ends) $1.06 $0.11 $0.18 $1.36 $1.06 $0.10 $0.14 $1.32 $0.04

                   

MM Mid-Volume                  

US (650K ends) $0.98 $0.07 $1.44 $2.54 $0.98 $0.05 $1.16 $2.26 $0.28

MX (1300K ends) $0.93 $0.07 $0.36 $1.38 $0.93 $0.05 $0.28 $1.30 $0.08

China (1900K ends) $0.83 $0.06 $0.14 $1.05 $0.83 $0.05 $0.11 $1.01 $0.04

Enabling Benefits of Laser CleavingEnabling Benefits of Laser Cleaving

• Cleaves fiber types that are not readily

mechanically cleaved

• Accommodates large OD and specialty fibers

• Suitable for MTP production

Field DataField Data

Assessment SC (MM) LC (MM)

(Laser) (Manual) (Laser) (Manual)

Total Connectors Evaluated > 50K - > 25K -

First Pass Yield 95% 85% 98% 85%

Cracks 1% 5% 1% 5%

Chips 4% 10% 1% 10%

Average Throughput, UPH 360 150 450 200

Average Cleave Height, um 95 400 60 300

Cleave Height Variability*, +/- um 20 300 20 300

Field Observations and Comments Laser cleaving removes operator dependence – excellent repeatability between shifts,

minimizes training Laser cleaving removes upstream epoxy bead variability – reduces polishing steps Laser cleaving decreases manufacturing costs – 2x throughput, improves yield

Field Observations and Comments Laser cleaving removes operator dependence – excellent repeatability between shifts,

minimizes training Laser cleaving removes upstream epoxy bead variability – reduces polishing steps Laser cleaving decreases manufacturing costs – 2x throughput, improves yield

Image Acquisition & ProcessingImage Acquisition & ProcessingExtending the CapabilityExtending the Capability

1 .Raw data

image

2. Image processing – Edge

3. Image processing – Best fit to edge

4. Best edge fit on original image

Enables automating the laser cleaving processEnables automating the laser cleaving process

• Field Module

• Single Step Polishing Support Module

• Fully automated platform

Extensions of Laser Cleaving TechnologyExtensions of Laser Cleaving Technology

Cleaving + Polishing + Cleaning + InspectionCleaving + Polishing + Cleaning + Inspection

ConclusionConclusion

• Advantages of Laser Cleaving Increased Quality & FPY

Faster – eliminate polishing process steps

Cheaper – lower process cost, less rework

Reliable – no detrimental impact

Field scalable

Enables Single Step Polishing

• Disadvantages None, of course

Thank You!Thank You!