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Automated Lens Measurement System Project # 05427. Team Members. Matt Place Frank Capristo Paul Thompson Melissa Groginski John Spalding Rhiannon Casale. Presentation Overview. Introduction/Project Overview Needs assessment Concept research Feasibility Top companies
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Automated Lens Measurement System Project # 05427
Team Members Matt Place Frank Capristo Paul Thompson Melissa Groginski John Spalding Rhiannon Casale
Presentation Overview • Introduction/Project Overview • Needs assessment • Concept research • Feasibility • Top companies • Summary of Senior Design I • Action plan for Senior Design II
Introduction • Bausch & Lomb has requested our team to research and evaluate methods and devices available to perform an automated, non-contact central thickness measurement • Upon evaluation of devices and systems available, the team will develop a fully functional offline station to test the top measurement systems available • Once testing is complete, a cost benefit analysis will be performed and an integration plan will be developed for the device/system that will best suit B&L’s needs • If time allows, the system will be integrated into either a PureVision or a Soflens production line
Process Flow Chart Molding Casting / Cure Release Hydration Inspection Packaging
Importance of Central Thickness • Optical properties • Durability • Comfort
Manual offline, mechanical contact method Lens must be discarded after inspection Lens is in wet state Audit level of ~1 – 2 % Current Process
Damage from Lens Handling O-ring Signature Extraction Tray Marks Tweezers Mark
Desired Process • Non-contact method • Automated and fully integrated into line • No manual, non-value added labor • Increased sampling rate • No discarding of good lenses after measurement is performed • Measurement performed at an earlier stage of production
Possible Points of Integration • Dry State: • In the assembled mold • After mold de-capping • After lens is released from mold • Wet State: • During cosmetic inspection • In blister package
Automated System Benefits • Ability to initiate SPC plan • Potential to perform 100% inspection • Reduces non-value added labor • Portable to future automated lines • Reduces individual lens cost by ~1-2%
Needs Assessment Mission Statement: To provide Bausch & Lomb with the most cost effective, non contact solution for accurately measuring the central thickness of a contact lens.
Requirements of New Process • Non-Contact method of measurement • Measure thickness range of 20 – 250 μm • Measurement tolerance of ±10 μm • Gauge R&R of ≤ 18% • User Interface • PLC Interface Plan • Extensibility to future products
Goals & Objectives • Satisfy Bausch & Lomb requirements • Research and test possible solutions • Determine most cost effective solution • Design all fixturing • Provide Bausch & Lomb with a cost benefit analysis • Provide Bausch & Lomb with an integration plan
Project requirements Measurement size Timeline Available technologies Vendor testing turnaround time Fixturing tolerances Cycle Time Constraints
Concept Research What: Companies and technologies Capable Of: Measuring the central thickness of a contact lens to Bausch & Lomb’s specifications Sources: Google, Thomas Registrar, Global Spec., and Bausch & Lomb Experts
Concepts Researched • Mechanical • Vision System • Capacitance • Laser Triangulation • Laser Autofocus • Optical • Ultrasonic
Eliminated Companies • Measurement spot size too large • Unacceptable measurement range • Improper measurement tolerances • Unable to measure due to product properties
Information Collection • Onsite visits • Lumetrics • Micro-Epsilon • Teleconferences • All other vendors • Major requirements captured
Patent Search • 13 related patents found • Visual Inspection Systems • Lens Production • Contact Methods • No conflicts • Key Words: • Thickness Measurement • Thin Films • Contact lenses
Product Specification Research • Contact Lens Quick Reference Guide • Base Curve • Mold information • Cost research
Feasibility Judging criteria Requirements Document Weighting criteria 5 = Most Important 1 = Least Important Scoring 1 = Not quite able to meet needs 3 = Exceeds needs
Feasibility Matrix (Cont.) • Device Model # • Working Height • Lens State for Measurement • Sensor/Controller Ratio • Sample Lead Time • Demo Lead Time • Length of Demo Period • System Lead Time
Test Results • Lumetrics • Excellent results, agrees with current system • Micro-Epsilon • Excellent results, agrees with current system • Panametrics • Excellent Results, agrees with current system • Mission Peak Optics • Free lens only, fair results
The Top Three • Lumetrics • Micro-Epsilon • Panametrics - NDT
Lumetrics Places the DI 330 Optigauge can measure: • With both halves of mold • With bottom mold half • Free lens
Lumetrics (Cont.) Possible install locations: • Before mold separation • Immediately before/after lens release from mold
Micro-Epsilon Places the optoNCDT 2400 can measure: • With bottom mold half • Free lens
Micro-Epsilon (Cont.) Possible install locations: • Immediately before/after lens release from mold • Before the lenses are placed on the trays
Panametrics - NDT • Lens in wet state • Inspection cell • Blister package
Panametrics – NDT (Cont.) • In-line on wet lens transfer machine
Design concerns • Capability of the sensor • Size of the sensor • Fixturing on the line • Accessibility for maintenance • What to do with reject lenses • Requirements of Bausch & Lomb
Summary of Senior Design I • Focused on research of companies and technologies available • 22 companies researched were narrowed down to 8 • 8 companies were sent samples • Feasibility analysis allowed team to separate top vendors • Top 3 companies chosen
Goals for Senior Design II • Present to Bausch & Lomb final recommendations for most cost effective functional device • Fully functional offline system • Integration plan
Action Plan for Senior Design II • Design and create fixtures for device and lens positioning • Bring in and test demonstration units from top vendors • Cost analysis • Evaluate manufacturing lines to develop an integration plan
Thank You • Bausch & Lomb • Bill Appleton – Project Coordinator • Ryan Williams – Project Sponsor • Dave Martz – Metrology Support • Kevin Beebe – Process Support • Prof. Stiebitz – R.I.T. Coordinator • Prof. Esterman – R.I.T. Mentor
Questions Any further questions?
Experimentation Plan • Small initial trial • Based on results, large trial, or halt trials • Gauge R&R • DOE as necessary
Senior Design II Timeline • SD II Timeline • Test Results: end of break ¾ • Me-fixturing-initial designs-(3/11); fabrication-(4/1) • Demo Units-1st units ordered (by spring)-2 week increments depending on L.T. • All-testing(doe)-(3/4)-(4/1): 4 wks • IE-Gauge r&r-(3/4)-(4/1):4 wks • Wet/Dry correlation-verification (3/18/05) • Cost analysis-on-going until (4/8) • Me-pfmea-4/8 • Final recommendations-4/8 • ee-implement plan-4/22 • me-stand alone station-4/22 • ie ergonomics analysis • ee-plc • proposal to Bausch-4/8
Wet – Dry Correlation • Correlation exists for SofLens products • Theoretical correlation for PureVision, need to verify with data
Lumetrics Keyence Elektrophysik FRT of America Mission Peak Optics Micro-Photonics Filmetrics Thermo Electron Corp. ABB Adetech Onosokki Lumetrics Mission Peak Optics Filmetrics MTI Instruments LMI Technologies, Inc. Micro-Epsilon ORYX Panametrics Company Research Long List Short List • MTI Instruments Inc. • LMI Technologies • Micro-Epsilon • Beta Laser Mike • ORYX • Panametrics • AccuSentry • Norman N. Axelrod and Associates • Dr. Schenk Inspection Systems • Optical Data Associates, LLC. • Solve TECH Inc
Eliminated Companies • Beta Laser Mike: • transmit and receive laser • Focal diameter too large for the application • Only good for flat applications • FRT of America: • They were not confident they could measure a curved surface such as a contact lens. • MicroPhotonics: • Could only measure up to 50 microns • SolveTech: • Capacitive method • Requires a much larger spot size than required • Develop fixture to position the lens accurately between two plates • Separation distance to small
Eliminated Companies • Keyence: • Device incapable of measuring the size and accuracy required • AccuSentry: • camera or vision system • Entire concept of a vision system discarded due to the current lack in adequate technology. • Norman N. Axelrod and Associates: • Do not sell a specific technology • On-site visit , analyze the problem, and custom develop a solution. • Adtech, ABB and Thermoelectron: • No response when contacted
Eliminated Companies • Dr. Schenk inspection systems: • Sell products to measure thin films • All products are meant to be installed on a high speed manufacturing line • Take a measurement based on the profile view of the thin film • Optical Data Associates, LLC: • Specializes in high precision inspection of various components for their optical properties • This company is just a testing firm and therefore would not be able to help or sell any technology that would meet the needs of the application. • Onosokki: • Contact method systems for measurement
Patent Search Several patents were found that are within the realm of the given application. The topics varied from a contact probe that measured the actual thickness of a contact lens, other technologies used in taking measurements of a contact lens, to automated visual inspections of a contact lens. Since the application that is being dealt with is more process oriented on the measurement of the central thickness of a contact lens the patents are not being infringed upon by our application.
Patent Search (Cont.) • Patent number 4,665,624 • deals with a soft contact lens analyzing apparatus. • This apparatus utilizes a fixturing device and several measurement scales to determine the diameter, sagittal depth and central thickness of a contact lens. All of the scales use probes that must come into contact with the actual lens. • A mechanical, contact system which is not what our application calls for. • Patent number 4,403,420 • Digital gauge for measuring the sagittal depth and thickness of a lens, and the related systems and methods • This method involves a fixturing device and several linear encoders to measure the diameter, sagittal depth and central thickness of a lens. Each of the encoders is connected to some type of probe that needs to come into contact with the lens. • A mechanical contact system in which our application will not infringe on.
Patent Search (Cont.) • Patent number 6,134,342: • Visual inspection method and apparatus for a contact lens. • The method described is automated. The visual inspection system is looking for defects such as foreign material, scratches, breakage and so forth. • No quantitative dimensional measurements performed and therefore does not have to do with our application. • Patent number 6,765,661: • A lens (such as contact lens) inspection method. • This system looks for such flaws as tears or surface defects. • No quantitative dimensional measurements preformed and therefore our application will not infringe with this patent.