background image

 

 

 

 

Redstone™ OSA305,  
OSA201C, OSA202C, 
OSA203C, OSA205C, 
OSA207C Optical  
Spectrum Analyzers 
 
Manual 

 

 

 

 

Summary of Contents for Redstone OSA305

Page 1: ...Redstone OSA305 OSA201C OSA202C OSA203C OSA205C OSA207C Optical Spectrum Analyzers Manual ...

Page 2: ...er 5 Using the Free Space Input 14 5 1 Table Mounting when Using the Free Space Input 14 5 2 Activation of Alignment Beam 15 5 3 Free Space Beam Alignment Example 17 5 3 1 Initial Visual Alignment 17 5 3 2 Adjust Software Settings 18 5 3 3 Final Alignment 19 5 3 4 Error Estimation 19 Chapter 6 Pure Air 20 Chapter 7 Software 21 7 1 Spectrum View and Interferogram View 21 7 1 1 Spectrum View 21 7 1 ...

Page 3: ...abVIEW Drivers 33 Chapter 10 Troubleshooting 34 Chapter 11 Technical data 35 11 1 Common Specifications 35 11 2 Model Specific Specifications 36 11 3 Update Frequency 36 11 3 1 OSA20xC 36 11 3 2 Redstone OSA305 36 11 4 Absolute Maximum Ratings 36 11 5 Trigger Specifications Redstone OSA305 only 37 11 6 Interlock Specifications Redstone OSA305 only 37 11 7 Internal Sources Specifications 37 Chapter...

Page 4: ...Optical Spectrum Analyzers 15 1 Waste treatment is your own responsibility 46 15 2 Ecological background 46 Chapter 16 Thorlabs Worldwide Contacts 47 ...

Page 5: ...Description Direct Current Alternating Current Both Direct and Alternating Current Earth Ground Terminal Protective Conductor Terminal Frame or Chassis Terminal Equipotentiality On Supply Off Supply In Position of a Bi Stable Push Control Out Position of a Bi Stable Push Control Caution Risk of Electric Shock Caution Hot Surface Caution Risk of Danger Warning Laser Radiation Caution Spinning Blade...

Page 6: ...is well ventilated since the gas will leak out from the instrument This product is for indoor use only To prevent potential fire or shock hazard do not expose the unit to any source of excessive moisture Only use the instrument standing on its feet WARNING The OSA20xC instruments include a He Ne laser The Redstone OSA305 includes a red laser and an infrared laser The classification of these lasers...

Page 7: ...d by Thorlabs for this unit to operate fault free provided that they are handled according to our requirements However Thorlabs does not warrant a fault free and uninterrupted operation of the unit of the software or firmware for special applications or this instruction manual to be error free Thorlabs is not liable for consequential damages Please visit the below link for Thorlabs General Terms a...

Page 8: ...interferogram is the autocorrelation waveform of the input optical spectrum By applying Fourier transform to the waveform the optical spectrum is recovered The resulting spectrum offers both a high resolution and a very broad wavelength coverage with a spectral resolution that is related to the optical delay range The wavelength range is limited by the optical bandwidth of the detectors and of the...

Page 9: ...n order to resolve them as two separate lines Note that when using the Wavelength Meter or Peak Track tools the number of significant figures can far exceed the Rayleigh spectral resolution as those tools use several data points and curve fitting techniques The Thorlabs OSAs utilize a built in actively stabilized reference laser to interferometrically record the variation of the optical path lengt...

Page 10: ...ty and higher resolution Redstone OSA305 models instead sample the interferogram at a fixed frequency of up to 1 MHz with an 18 bit ADC while the retroreflector platform moves at a constant speed controlled by a PID loop The data is resampled to fit up to 128 data points per reference laser period A high speed USB link transfers the interferograms to the ThorSpectra software which is highly optimi...

Page 11: ... displayed in a floating window or docked just below the main data display presenting the overall spectrum The central wavelength 𝜆 is calculated by counting interference fringes periods in the interferogram from both the input and reference lasers according to the following formula 𝜆 𝑚 𝑚 𝑛 𝑛 𝜆 Here 𝑚 is the number of fringes for the reference laser 𝑚 is the number of fringes from the input laser ...

Page 12: ... optical path difference OPD between the two branches in the interferometer In this case it is easier to work with wavenumbers inverse centimeters 𝑘 1 𝜆 than wavelength nanometers or frequency terahertz From the Fourier transform the relation between spectral resolution in cm 1 and OPD in cm is simply Δ𝑘 1 𝑂𝑃𝐷 Assume we have two narrowband sources such as two lasers with a 1 cm 1 energy difference...

Page 13: ...ettings are used Figure 4 and Figure 5 show the dependence of the noise floor on the wavelength and OSA model Figure 4 Noise Floor in Absolute Power Mode i e the mode for measuring narrowband light sources 0 2 4 6 8 10 12 10 0 10 1 10 2 10 3 10 4 10 5 OSA20xC High OSA20xC Low OSA305 Low OSA305 Medium Low OSA305 Medium High OSA305 High Resolution in Spectrometer Mode Resolution pm Wavelength µm 1 1...

Page 14: ... are not located at the test distances will still be included in the ORR value 𝑂𝑅𝑅 𝜈 𝑃 𝜈 max 𝑃 𝜈 𝜈 2 THz If the ORR is not higher than the optical signal to noise ratio of the source to be tested the measurement will indicate the limit of the OSA rather than the tested source Figure 6 and the table below provide some example values for the optical rejection ratio of the OSA205C and Redstone OSA305...

Page 15: ...econd function i e the boxcar That is if 𝐹 𝑓 is defined as the Fourier transform of 𝑓 then 𝐹 𝑓 𝑔 𝐹 𝑓 𝐹 𝑔 The Fourier transform of the interferogram is the spectrum and the Fourier transform of a boxcar function is the sinc function sinc 𝑥 sin 𝑥 𝑥 The sinc function is an oscillating function with diminishing amplitude away from zero Therefore the Fourier transform of a measured finite interferogram...

Page 16: ... the Redstone OSA305 instrument there are four BNC connectors some of which can be used to externally trigger a measurement The four BNC connectors are labeled on the instrument back panel and provide the following functionality Trigg When the negative flank of a signal is registered by this input the Redstone OSA will start an acquisition with the current settings Note that the trigger will be ig...

Page 17: ...e interlock jack are listed in Section 11 6 Interlock Specifications Redstone OSA305 only Note that the Redstone OSA305 requires the reference laser source to collect accurate interferograms hence with the Interlock unplugged the instrument is disabled Further the sole output for the reference laser is the Calibration output fiber port on the front of the instrument ...

Page 18: ... on the OSA20xC front Figure 9 Free Space Input Left and FC PC Input Right on the Redstone OSA305 front 5 1 Table Mounting when Using the Free Space Input The OSA20xC interferometer assembly normally floats on gel bushings inside the case When coupling an external light source to the free space input it may be desirable to lock the interferometer to a stable surface such as an optical table This c...

Page 19: ...ace input accepts a beam height of 117 mm 4 6 above the table surface If the beam height of your experimental setup is not consistent with the free space input we recommend using a periscope assembly such as Thorlabs RS99 M periscope to adjust the beam height to that of the OSA s input Do not use longer posts to elevate the OSA 5 2 Activation of Alignment Beam The OSA20xC models include a red alig...

Page 20: ... in the ThorSpectra software However the second optical arm is not blocked and light from this arm is incident on the detectors This DC signal of the detectors is available when the alignment beam is activated and can be of assistance in the alignment process Note that when the Free space Alignment window is open the detector offset is disabled and the saturation level is decreased When clicking t...

Page 21: ...st source to steer the input source into the OSA using a viewing card such as Thorlabs Item VRC2 and or an alignment plate such as Thorlabs Item CPA2 to aid in the alignment Then use the mirror closest to the OSA to point the alignment beam emitted by the OSA at the center of the input source Repeat these steps until the test source beam and alignment beam overlap over the entire beam path When ac...

Page 22: ...s should now open the Signal window under the Instrument menu and click the Auto box below the applicable detector to toggle to Manual mode opening the Free space Alignment window automatically manages these settings for Redstone OSA305 Adjust the gain level s such that a strong signal is achieved while not saturating the detector s a signal value in the range of 10 to 80 is suggested It is recomm...

Page 23: ... 5 3 4 Error Estimation When the signal cannot be optimized further the wavelength error caused by any remaining misalignment can be calculated Measure the offset 𝑑 between the source exit point and the alignment beam The wavelength error is the path difference between the alignment beam and the source beam and can be estimated as 1 cos tan where 𝐷 is the distance between the source and the detect...

Page 24: ...ttach two hoses one supply and one return to the 1 4 inner diameter quick connections on the back of the OSA Compatible tubing is sold as Thorlabs Item PACU TG WARNING If purging gas other than dry air is used make sure that the environment for the operator is well ventilated since the gas will leak out from the instrument Figure 15 OSA20xC Inner Diameter Quick Connections for a Purified Air Suppl...

Page 25: ...terferogram view Only interferograms are shown Only analysis tools and math tools applicable to interferograms are enabled Spectra are still calculated in the background but will not be displayed until Spectrum view is selected Interferogram view is unavailable when operating in Basic level To switch between the views use the quick switch button found in the Settings bar or use the short cut Ctrl ...

Page 26: ...tors might not be at the same level which presents itself as a ramp in the spectrum when there is no light in the overlap region However the transition is power calibrated so that the two detector responses match with light input 7 2 2 Repeated Measurements The autogain algorithm will continuously investigate the collected interferogram s and make slight adjustments to gain and or offset to ensure...

Page 27: ...spectrum but if the repetition rate of the input light is higher than about 7 kHz Redstone OSA305 or 30 kHz OSA20xC the spectral ghosts will be pushed out from the vicinity of the true peak and the spectrum of the pulsed light will be close to that of a corresponding CW light source even using a normal Single or Repeat measurement For those cases in which the spectral ghosts are interfering with t...

Page 28: ...llow the instructions A fiber for infrared wavelengths with a FC APC connector on one side and a FC PC connector on the other side is required such as the Thorlabs Item P5 SMF28E FC 2 one such fiber is included with the instrument at delivery The reference laser can be accessed through the FC APC connector on the front panel under the Calibration Output label Figure 21 Wavelength Calibration dialo...

Page 29: ...will be updated as the quotient between two other traces to the left in the Trace controls bar The Trace Label will signify how the trace will be calculated e g B A or A C This trace will be updated when any of the traces involved in its calculation are updated This option is available under the Calculate sub menu for traces with at least two traces to the left e g this option is available for tra...

Page 30: ...the periodicity of the collected interferograms before apodization is performed The number of cycles in the interferogram are counted and compared to the number of cycles in the interferogram of the built in reference laser see Section 4 1 Introduction When the Wavelength Meter tool is enabled the analysis results are displayed in a floating window or docked to the main display area The calculated...

Page 31: ...r saturation in the interferogram Whenever a saturated interferogram is analyzed the analysis result will be displayed in red and the error message Saturated Interferogram will be displayed below the analyzed result The tool window shows the minimum maximum mean and standard deviation of the coherence lengths that have been measured while the coherence length tool has been active The values are up...

Page 32: ...Rev D June 16 2022 Page 28 Figure 25 Script Window For more information on the syntax and commands available to scripts please see the separate manual Scripting ThorSpectra installed with the ThorSpectra software and found in the Windows Start menu ...

Page 33: ...evel 8 2 Advanced Settings When operating in Advanced level there are four tabs in the Active Device page 8 2 1 Acquisition Settings In the Acquisition tab it is possible to specify the instrument settings The Acquisition Interval is the minimum time between two subsequently collected interferograms Setting this to zero default will cause the software to perform the measurements as fast as possibl...

Page 34: ...ironment settings tab it is possible to set whether the temperature atmospheric pressure and relative humidity saved in each interferogram and spectrum should be measured using the built in sensor in the instrument or be set to a fixed value 8 2 3 Interferogram Settings In the Interferogram settings tab it is possible to set the processing that is applied to each collected interferogram The type o...

Page 35: ...processing of the spectra Figure 29 Spectrum Processing Settings Zero Fill Factor If not zero the interferograms will be extended with zeros before the Fourier transform is applied A value of one means that the interferogram will be doubled in length and a value of two means that the interferogram will be quadrupled This increases the number of data points in the spectrum and increases the apparen...

Page 36: ... is not reversible Spectral Smoothing If the spectra are collected at a much higher resolution than necessary smoothing can be applied to reduce the noise in the measurement Phase Correction This option is not selectable and is only for information purposes When the interferogram is transformed into a spectrum the phase error of the interferogram will be corrected to reduce the error in the measur...

Page 37: ...vers are based on functions found in the FTSLib dll which is also used by the application GUI See Thorlabs Manual FTSLib in the Windows Start menu for details The drivers can be accessed from the Windows Start menu under Thorlabs LabView The LabVIEW drivers support LabVIEW 2010 and later in 64 bit OS see the readme pdf for details Open the Tree VI to get a categorized overview of the drivers and e...

Page 38: ...sure at least one trace is set to Write or Average see Section 7 3 17 3 1 Trace Update Options Certain combinations of settings have a very slow update rate especially High Resolution High Sensitivity Please check the green progress bar in the bottom left corner If the bar is visible the device is still acquiring or processing data Is the acquisition interval set to anything other than zero millis...

Page 39: ... 149 mm x 475 mm 12 6 x 5 9 x 18 7 541 mm x 224 mm x 533 mm 21 3 x 8 9 x 21 0 a After a 20 minute warm up for OSA20xC for a single mode FC PC terminated patch cable at an operating temperature of 20 ºC to 30 ºC b Specified in parts per million which corresponds to nearly seven significant figures depending on the specification For instance if the wavelength being measured is 1 µm the Wavelength Me...

Page 40: ...ure OSA201C 350 1100 nm 50 dBm nm 350 500 nm 60 dBm nm 500 1100 nm Uncoated CaF2 10 C to 40 C OSA202C 600 1700 nm 65 dBm nm 600 700 nm 70 dBm nm 700 1700 nm OSA203C 1 0 2 6 µmd 10 000 3846 cm 1 70 dBm nme OSA205C 1 0 5 6 µm 10 000 1786 cm 1 40 dBm nm OSA207C 1 0 12 0 µm 10 000 833 cm 1 30 dBm nm 1 0 2 0 µm 40 dBm nm 2 0 12 0 µm Uncoated ZnSe 10 C to 35 C Redstone OSA305 1 0 5 6 µm 10 000 1786 cm 1...

Page 41: ...aximum Input Voltage 5 5 V Acquiring Data AUX Out LOW Level Output Voltage Max 0 1 V I 100 µA HIGH Level Output Voltage Min 4 7 V I 100 µA Interlock Specifications Interlock Switch Requirements Must be Normally Open Dry Contacts Apply No External Voltages to the Interlock Input Type of Mating Connector 2 5 mm Mono Phono Jack Open Circuit Voltage 5 VDC Short Circuit Current Typical 0 5 mA OSA20xC R...

Page 42: ...Optical Spectrum Analyzers Chapter 12 Mechanical Drawings Rev D June 16 2022 Page 38 Chapter 12 Mechanical Drawings 12 1 Redstone OSA305 12 1 1 Dimensions ...

Page 43: ...Optical Spectrum Analyzers Chapter 12 Mechanical Drawings Page 39 STN053070 D02 12 1 2 Front and Back Panels ...

Page 44: ...Optical Spectrum Analyzers Chapter 12 Mechanical Drawings Rev D June 16 2022 Page 40 12 2 OSA20xC 12 2 1 Dimensions ...

Page 45: ...Optical Spectrum Analyzers Chapter 12 Mechanical Drawings Page 41 STN053070 D02 12 2 2 Front and Back Panels ...

Page 46: ...pment generates uses and can radiate radio frequency energy and if not installed and used in accordance with the instructions may cause harmful interference to radio communications However there is no guarantee that interference will not occur in a particular installation Thorlabs is not responsible for any radio television interference caused by modifications of this equipment or the substitution...

Page 47: ...n EN 61000 3 2 AC Power Line Harmonic Emissions EN 61000 3 3 Voltage Fluctuation and Flickers EN 61000 4 2 Electrostatic Discharge Immunity Criterion C EN 61000 4 3 Electromagnetic field immunity Criterion A EN 61000 4 4 Electrical Fast Transient Burst Immunity Criterion B EN 61000 4 5 Power Line Surge Immunity Criterion B EN 61000 4 6 Conducted RF Immunity Criterion B EN 61000 4 8 Magnetic field ...

Page 48: ...g caused by random molecular motion and pressure broadening caused by collisions between molecules Doppler broadening leads to a Gaussian line shape with half width at half max given by 𝛼 𝜈 𝑐 2𝑘 𝑇 𝑚 where 𝑚 is the molecular mass In contrast pressure broadening leads to a Lorentzian line shape with half width at half max given by 𝛼 𝑇 𝑇 𝑃 𝑃 𝛾 1 𝑞 𝛾 𝑞 where 𝛾 is the broadening caused by collisions wi...

Page 49: ...n Beer Strong 𝐹 𝑥 0 045335 0 554883 1 𝑥 0 399782 1 𝑥 Triangular 𝐹 𝑥 1 𝑎𝑏𝑠 𝑥 Cosine 𝐹 𝑛 sin 𝜋𝑛 𝐿 1 Hann 𝐹 𝑛 1 2 1 cos 2𝜋𝑛 𝐿 1 2 Pass Hann 𝐹 𝑛 1 4 1 cos 2𝜋𝑛 𝐿 1 Hamming 𝐹 𝑛 0 54 0 46 cos 2𝜋𝑛 𝐿 1 3 Term Blackman Harris 𝐹 𝑛 0 4243801 0 4973406 cos 2𝜋𝑛 𝐿 1 0 0782793 cos 4𝜋𝑛 𝐿 1 4 Term Blackman Harris 𝐹 𝑛 0 35875 0 48829 cos 2𝜋𝑛 𝐿 1 0 14128 cos 4𝜋𝑛 𝐿 1 0 01168 cos 6𝜋𝑛 𝐿 1 Gaussian 𝐹 𝑥 𝑒𝑥𝑝 𝑥 2 0 4 In the...

Page 50: ...horlabs products such as Pure OEM products that means assemblies to be built into a unit by the user e g OEM laser driver cards Components Mechanics and optics Left over parts of units disassembled by the user PCB s housings etc If you wish to return a Thorlabs unit for waste recovery please contact Thorlabs or your nearest dealer for further information 15 1 Waste treatment is your own responsibi...

Page 51: ...on USA Canada and South America Thorlabs Inc sales thorlabs com techsupport thorlabs com UK and Ireland Thorlabs Ltd sales uk thorlabs com techsupport uk thorlabs com Europe Thorlabs GmbH europe thorlabs com Scandinavia Thorlabs Sweden AB scandinavia thorlabs com France Thorlabs SAS sales fr thorlabs com Brazil Thorlabs Vendas de Fotônicos Ltda brasil thorlabs com Japan Thorlabs Japan Inc sales th...

Page 52: ...www thorlabs com ...

Reviews: