Analisi del Focus-shift su sorgenti multikw Luca Porcelluzzi Ophir Spiricon Europe GmbH
Content Content Ophir Spiricon Europe GmbH Beam Characterization Applications Summary 2
Ophir Spiricon Europe GmbH Darmstadt - Germany European Support : Sales Service Recalibration For OPHIR power and energy meter SPIRICON beam profiler PHOTON beam profiler and goniometer Any laser Any Wavelength ( from soft X-ray to THz) Any power (from sub fw to over 120 kw) Any energy (from sub nj to over 5000J) Any size beam (from micron to meters) 3
Content Content Ophir Spiricon Europe GmbH Beam Characterization Applications Summary 4
Beam Characterization Beam Characterization Power / Energy (W / J) Beam Diameter (cm) (Intensity Distribution) Motivation why? Power Density (W/cm²) Power density (W/cm²) defines how the laser interacts with the matter / application Changes with time 5
High power Beam Characterization Power Density (W/cm²) will change with time Laser Systems are made of Physical Matter Laser Source Laser Delivery Laser Processing Head Nd:YAG Yb:Fiber Direct Diode Disc Free-Space Optics (Usually Several) Process Fiber Shutters Apertures Purge Gas Beam Shaping Optics Scanning Mirrors Focusing Lenses or Mirrors Process Gas/Nozzle Protective Cover Glass 6
High power Beam Characterization Knowing the laser power with the focus spot size and location is critical in many industrial applications. 1 2 3 W cm 2 7
Meaning of Beam Profiling How Do We Measure Laser Performance At high power industrial lasers? Overtake the Vintage: Single data points Moment in time Subjective interpretation 8
Content Content Ophir Spiricon Europe GmbH Beam Characterization Applications Summary 9
Application Example for Power/Energy Example 1 Two identical laser machines but different results! 10
Application Example for Power/Energy Laser 1 Laser 2 Before Service Energy- Sensor 5J Energy- Sensor 4J 11
Application Example for Power/Energy Power: High power Solution for Example 1 1k-W 5k-W 6k-W 10k-W 12k-W 15k-W 30k-W 120k-W 12
Application Example for Power/Energy High power Solution for Example 1 Power 16kW: 13
Application Example for Power/Energy Example 2 Two identical laser machines with same output energy but different results! 14
Application Example for Power/Energy Laser 1 Laser 2 Energy- Sensor 5J Energy- Sensor 5J 15
Application Example for Power/Energy Laser 1 Laser 2 Focal- Plane Energy- Sensor 5J Energy- Sensor 5J 16
Application Example for Power/Energy Example 2 Two identical laser machines with same output energy but different results Reasons: different divergence (laser, telescope, beam shaping optics) Solution: Beam Profiler for detecting waist location 17
Beam Profiling Beam Profiling for detecting waist location of 1 KW Fiber Laser with Camera-Based Profiling System Laser System: cw-fiber laser 1070nm 600µm fiber 1kW Class 1 workstation Spiricon Beam Profiler system Software: BeamGage Professional Camera: SP620U Attenuator: LBS-300-NIR + SPZ17015 13,5% of peak beam diameter measured method 18
Beam Profiling Beam Profiling for detecting waist location of 1 KW Fiber Laser with Camera-Based Profiling System 19
Application Example for Beam Profiling Example 3 Laser machine with constant output energy + constant focal spot size but different results over time! 20
Application Example for Beam Profiling Laser Focal- Plane Energy- Sensor 5J 21
Application Example for Beam Profiling BeamWatch Non-contact, Focus Spot Size and Position monitor for high power YAG and Fiber lasers 22
How does the BeamWatch works 23
Rayleight scattering for Beam Profiling An image of the Rayleigh scatter is created by the beam as it travels through air molecules. 24
Rayleight scattering and laser measurements Software finds the beam at all points along its axis. 25
Rayleight scattering and laser measurements Finding the waist, then computes the caustic curve fit. 26
Which measurements? 27
Which measurements? Instrument BPP q(mr) d(µm) Reference 6.89 64.97 424.00 Rayleigh 7.00 65.84 423.44 D% 1.66% 1.34% -0.13% Instrument BPP q(mr) d(mm) Reference 9.99 63.23 632.00 Rayleigh 9.79 61.23 639.42 D% -2.00% -3.17% 1.17% 2KW Fiber Laser 20KW Fiber Laser 28
Which measurements? raw data fit result 29
Data from BeamWatch 6kWatt Focus-shift 1mm 1kWatt 4kWatt Fokusshift 1,2mm 1kWatt 5kWatt Fokusshift 3mm 10kWatt Fokusshift 15mm Graph of Beam Waist Position vs. Time Focus Shift 30
Data from BeamWatch 31
How to install BeamWatch - 1 Measurement of 100KW Fiber Laser 100K-W Power Measurement System BeamWatch 32
How to install BeamWatch - 2 Measurement of 16KW Disc Laser BeamWatch 30K-W Power Measurement System 33
Data from BeamWatch Measurement of 16KW Disc Laser 34
Data from BeamWatch 35
BeamWatch - Unique features Almost instantaneous measurement Nothing in the beam path No moving parts Measure focus spot drift in 20 secs No max. power limit 36
Content Content Ophir Spiricon Europe GmbH Beam Characterization Applications Summary 37
Summary Optimize application development Process Validation: Moving or Copying a process from one system to another Batch Validation: PROOF that the laser remained consistent during the processing of a batch of parts Predict laser preventive maintenance increase manufacturing efficiency Component Changes (optics, lamps, fibers) Troubleshooting, Laser Parameter Modification Thermal instabilities in the laser system resulting in changes in laser power and focused spot size location Laser performance measurement is the best way these changes can be viewed, analyzed, and managed Less downtime of laser machine, Higher Quality & Yield 38
Thank you 39
Rayleight scattering and laser measurements An image of the Rayleight scatter is created by the beam as it travels through air molecules. Particle diameter: d, refraction index: n, intensity: I, distance: R and under defined angle for the Wavelentgh: λ The image in BeamWatch is not the laser beam itself. 40