Transcript Laser Cleaving of Optical Connectors

Laser Cleaving of Optical
Connectors
Didi Hachnochi
VP Engineering & R&D
Duane Dinkel
President
Sagitta Incorporated
655-H Fairview Road
Simpsonville, SC 29680
Introduction
• The Problems
 Mechanical cleaving – operator and tool-dependent quality (handscribe, 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 Process
Cut to
Length
Assembly
II
Strip &
Clean
Assembly
I
Insertion
Into ferrule
Epoxy
Application
Fiber
Cleave
Air Polish
“Denub”
Epoxy
Removal
Polish
Sequence
Clean
Endface
Visual
Inspection
Geometry
Inspection
Optical
Inspection
Epoxy
Cure
Label
And Pack
Uncleaved Connector Tip
Ceramic
Ferrule
300-1200um
5-15 mm
5.0 – 15.0mm
Epoxy
Bead
Fiber
“Stinger”
Manual Cleave Process
Mechanical techniques represent > 90% of the industry
Hand Polish Process – “Denubbing”
Before
After
300
300––500 um
300 – 1200 um
– 1000um
Coarse Hand
Polishing Material
Fiber Stub &
Epoxy Bead
Hand polishing can consume up to 30 sec per end
Manual Cleave – The Problems
• Variable Epoxy Bead Size
 Polishing process variable
 Requires hand polish to remove
• Variable “Stinger” Length
 Extra polishing step
• Poor Cleave = Bad Endface
 Yield (and quality) problem
 Core cracks
 Endface chips
⇨ reworks!
Epoxy Bead Size Range
Height:
300 - 1200um
Volume:
0.02 – 0.05 mm3
Cleaved Fiber Range
300 – 500um
Laser Cleaver Animation
Laser Cleaving Principal
Combines Cleaving + Denubbing + Epoxy Removal
From Curing
Into Polishing
Ceramic
Ferrule
300 – 1200um
5.0 – 15.0mm
Epoxy
Bead
Fiber
“Stinger”
80 – 120um
Focused CO2 beam spot
passes thru fiber and epoxy
Simplex Connector Before/After Cleave
Small epoxy bead
Large epoxy bead
Before
Cleave
Hand Cleave
Bellow epoxy!
After
Laser
Cleave
Laser Cleave
Fiber stub & residual epoxy < 100μ
Field Performance - Simplex
Protrusion Variation, um
Cleave Height Control
Cleave Height Reproducibility
30
USL
20
10
TGT
0
-10
-20
LSL
-30
0
20
40
60
80
100
Sample #
Limits must be sufficient to eliminate polishing steps
MT Connector Cleaving Progress
Before
Ferrule
Epoxy
12 Fibers
After 2 cycles
After 4 cycles
Field 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 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 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”
Cost Benefits of Laser Cleaving
Combines scribing + denubbing + epoxy removal
• Reduces consumable costs
 Minimizes abrasive consumable cost (1-2 polishing
operations eliminated)
 Eliminates scribe blade wear-out
• Higher yields
• Reduces headcount (or increases throughput)
Cost Benefits of Laser Cleaving
Manual
Laser Cleaving
BOM
CoC
L&O
Total
BOM
CoC
L&O
Total
Savings, $/end
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
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
SM Low-Volume
MM Mid-Volume
Labor ⇩
Cost of Consumables ⇩
(abrasive films, scribes, etc.)
Yields ⇧
COGS reduces by 5 – 10%
(Shaving $50M annually out of industry costs)
Enabling Benefits of Laser Cleaving
• Cleaves fiber types that are not readily
mechanically cleaved
• Accommodates large OD and specialty fibers
• Suitable for MTP production
Field Data
Assessment
SC (MM)
LC (MM)
(Laser)
(Manual)
(Laser)
(Manual)
> 50K
-
> 25K
-
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
Total Connectors Evaluated
First Pass 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 & Processing
Extending the Capability
1. Raw data
image
3. Image processing – Best fit to edge
2. Image processing – Edge
4. Best edge fit on original image
Enables automating the laser cleaving process
Extensions of Laser Cleaving Technology
• Field Module
• Single Step Polishing Support Module
• Fully automated platform
Cleaving + Polishing + Cleaning + Inspection
Conclusion
• 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!