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ApplicAtion note

NaNoScaN

commoN cauSeS of Damage to ScaNheaDS
& ReaSoNS foR out-of-toleRaNce coNDitioNS

IntroductIon

Problems you may encounter with a nanoScan 
scanning-slit beam profiler are due to either scanhead 
damage, or out-of-tolerance conditions.
Scanhead damage can be categorized into two main 
types; Laser and Mechanical. Laser damage is the most 
prevalent, and results from exposure to lasers with 
excessive laser power/energy density, and or high 
average power. the damage can be classified into 2 
categories, designated “Instantaneous” and “Long-term”.

Summary of Contents for Ophir nanoScan

Page 1: ...am profiler are due to either scanhead damage or out of tolerance conditions Scanhead damage can be categorized into two main types Laser and Mechanical Laser damage is the most prevalent and results from exposure to lasers with excessive laser power energy density and or high average power The damage can be classified into 2 categories designated Instantaneous and Long Term ...

Page 2: ...culate environments and repetitive motion Mechanical damage includes bent motor shafts distorted slits plugged slits and broken signal cables Out of tolerance conditions are either system related including problems associated with circuit or motor failure or the scanhead is not appropriate for the application such as using a Silicon detector to measure a 1550nm source or a 25µm slit for a 10µm bea...

Page 3: ...e damaged if stopped in the beam and if this occurs the detector may also be damaged Use of a beam dump is recommended until the drum is spinning When running long term tests with NanoScan Configure the PC Power Management to NEVER go off and to NOT ALLOW Automatic Updates These cause the computer to reboot closing the NanoScan program and stopping the NanoScan drum potentially subjecting it to th...

Page 4: ...ing on the application and measurement configuration while contamination by many particles is more likely to create a problem With pinhole apertures a single particle can be disastrous Therefore when the system is not is use it is recommended that the protective plastic cap be used to cover the scanhead entrance aperture to avoid possible contamination If inconsistent performance is observed and c...

Page 5: ... of visual damage occurs The average irradiance is defined as the average power divided by the beam area at the 1 e beam diameter All tests were performed under normal NanoScan operating conditions with the aperture slits moving Damage to the slit apertures can occur at much lower power levels if the laser beam is directed into the slit apertures while the apertures are stationary The tests were p...

Page 6: ...l scanheads Fluence exposure thresholds for pulsed lasers are given in Table 2 for nickel alloy blackened nickel alloy and copper slit apertures Table 1 Recommended maximum average laser irradiance incident on blackened and unblackened Nickel NanoScan slit apertures for short time exposures Aperture Slit µm Visual Damage Threshold W cm2 355nm 532nm 1064nm 10 6µm Unblackened 1 2 2x105 3x105 1x106 N...

Page 7: ...or the time limit because it neglects thermal conduction into the drum For reported times 5minutes it is generally safe to operate with continuous exposure but caution is advised Exposure time limits for nickel alloy and copper slit apertures are given in Table 3 Long Term Drum Heating Exposure Limits The long term exposure limits for drum heating are based on a heating model where all the laser p...

Page 8: ...ue to bending the cable to too tight a radius or from repetitive bending when the scanhead undergoes repetitive motion Cable Laser The cable can be severed by a high power laser when accidentally exposed to high power energy lasers This type of damage is avoided by careful routing of the cable Out of Tolerance Conditions Out of tolerance conditions are of two main types either system related or us...

Page 9: ...red Software Solutions BeamGage Standard BeamGage Professional Dual or Single Monitor Set Up M Measuring System Medical Military Industrial Processes Scientific Research Applications Scanning Slit Camera products for almost any wavelength from 13nm 3 000µm ...

Page 10: ... Viton is a registered trademark of E I Dupont Wilmington DE www ophiropt com 2020 MKS Instruments Inc Specifications are subject to change without notice Ophir Spiricon LLC Calibration Team 3050 North 300 West North Logan UT 84341 Phone 435 753 3729 E mail service ophir usa mksinst com For latest version please visit our website www ophiropt com photonics Copyright 2020 Ophir Spiricon LLC N Logan...

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