Most anyone working with lasers today will tell you that it is an exciting field. Applications of coherent light at different wavelengths are ever increasing and show no signs of plateauing. The skills required to understand, troubleshoot, and correct problems with lasers, and the systems they are a part of, are in high demand. It's all part of an evolution whereby yesterday's laser technician has turned into today's laser technology specialist.
Articles
By G.E. Slobodzian, Director of Engineering, Retired, Ophir-Spiricon
Part 1: New Camera Technologies
...The selection of a sensor to accurately measure the power of a laser or energy of a pulsed laser can seem like a simple and easy procedure. However, many times the selection process is limited to choosing a sensor that only meets the range of power or energy to be measured, leaving out several other essential criteria of the laser specifications; that without their consideration, can allow the wrong sensor to be selected, the laser to be measured inaccurately and likely to cause the sensor to fail prematurely.
Having worked in laser marking and engraving for several years, I can say that there is a certain mindset when it comes to laser quality that, in some cases, could be a dangerous one, especially in industrial applications. The mindset is, “If the laser is making a mark, then why check the performance of the laser?” Let’s discuss this as it relates to several different laser applications, including why this mindset could be causing you to lose time and money.
...This document discusses the interpretation and basis for stated measurement accuracy of Ophir Laser Power/Energy meters.
1. General Discussion
2. Combination of Errors and Total Error
3. Analysis of Power and Energy Calibration Errors
4. Detailed Analysis of Power and Energy Calibration Errors
This document was created to assist our valued customers in the proper care and maintenance of Ophir thermal laser power sensors. The following information is for reference only. If you have any reason to believe that the sensor is no longer performing within the original specifications,we always recommend that you send it in for repair and/or recalibration by our trained technicians to bring the unit back to the proper NIST traceable standards. We believe that Ophir thermal sensors can be used for many years without any repairs when used with the proper laser optical setup. We hope that this document will enable you to also enjoy the long life and reliable results for which Ophir-Spiricon is known.
In many industries LEDs are replacing traditional broadband light sources such as mercury, deuterium, Xenon, and quartz-halogen lamps. Systems and applications transitioning to LEDs are reengineered in terms of optics, electronics, heat management and more. Similarly, the equipment used by professionals to measure the output of these sources needs to be fitted for measuring LEDs.
Measuring lasers can be a daunting task, particularly as the power or energy levels get higher. Many applications require that precise information about laser beam sizes be known, but these lasers may be capable of damaging the profilers. The slit-based profiler, such as the Photon NanoScan is ideally suited for measuring these higher power lasers, because it can accept a relatively high powered beam directly, without attenuation. Nonetheless there are limits. Determining these limits can be complicated, especially if the laser is operated...
Watch the Measuring M², Beam Propagation Analyzers video
Use the focal spot size calculator calculator to see how M-...
One of the laser’s most useful properties is that it can propagate over great distances defining a straight line, and many optical systems are designed to exploit this property. Therefore, beam profilers are often used to verify the performance of lasers and optical systems to avoid problems caused by bad alignment or to streamline the manufacturing processes of these devices.
By William Owens, Engineering Dept., Ophir-Spiricon, LLC
So how did this whole concept of an “Automation Interface” come about? Well, here is my short-short history on the topic. In the beginning, all programs were simple. Users had simple menus with a few equally simple commands. Most commands had shortcut-key combinations that were fun and easy to remember. The world was a wonderful place. Then somebody got the bright idea that adding “New Features” to an application was cool...
When compared with the cost of Plexiglas blocks, burn papers, or even IR cards, a beam profiler may seem expensive. Almost anyone who has sold test equipment, at one time or another has heard the complaint from a potential customer, "It's too expensive!" In fact, almost anyone who has ever sold anything has heard this lament. In most sales training courses there is an extensive section on overcoming objections, and the most prominent objection discussed is always the "it's-too- expensive" objection...
BeamGage Professional and BeamGage Enterprise version 5.7 are supported with Automation via .Net components. Both include a LabVIEW example that can be run with the LabVIEW Run-Time Engine that is provided with the BeamGage software CD or available for free download from National Instruments.
Figure 1. BeamGage and LabVIEW.
The attached pages from the BeamGage User...
As the BeamScan products reach the end of their useful lifetime, we are often asked which NanoScan models most closely match an existing BeamScan model. There are far fewer configurations of NanoScan head than there were BeamScans, because some of the features that were hardwired into BeamScan models are software adjustable in the NanoScan.
For example, some BeamScans were wired to run at 5Hz, instead of...
Proper alignment of the MS-1780 is essential for its operation, and this can occasionally seem difficult to achieve. Here is a simple method for making sure the system is properly aligned to get the “first light” conditions that will allow easy fine tuning for experimental results.
In order for the system to work properly the laser beam needs to enter the optical center of the aperture on the horizontal axis of the instrument. In order to be able to fine-adjust the beam it is useful to use steering mirrors to direct...
We are frequently asked how one can output data from the NanoScan to other programs for additional analysis or publication. Depending nature of the desired end results there can be many answers to this question. In this application note we will try to explain these different solutions.
Active X
The NanoScan Pro analysis software program includes the Active X server. This allows the user to write programs and routines in a number of platforms, such as Visual Basic, LabVIEW, Excel and others, which will control the NanoScan...
In order to get proper results from the ModeScan 1780 beam profiler, it is necessary to understand which lens to use and where to locate it for particular parameters of the laser under test. The ModeScan 1780 calculator The calculator includes a worksheet that computes laser propagation parameters in...
The NanoScan slit and pinhole aperture substrates are very thin and extremely fragile. Any physical contact will likely damage them. For example, fiber tips placed too close to the aperture can easily damage a slit. Treat the slits with care; because of their fragility, never touch them with anything!
Debris such as dust particles can lodge in the very fine openings of the slits or pinholes and obstruct the passage of the incident beam. This can compromise instrument performance, resulting in...
The NanoScan 9mm/5µm (aperture/slit) is the best scan head for measuring M-Squared with NanoModeScan. We do not, however, recommend using the smallest scan heads (3.5mm aperture, 1.8μm slit) for M2 measurement, because they are subject to a distortion effect called vignetting: Scanning slits are usually thought of as two dimensional, but they also have thickness, based on the material that they are cut into. Since this material is...
Included below are helpful hints for installing the Pyrocam III, particularly in Windows 7.
Note; in general we recommend to not use 4-pin on-board 1394 FireWire ports (that can be found on some laptop computers) since they tend to be less reliable and/or cause the Pyrocam III to freeze when running. Instead we recommend using 6-pin plug-in adapter FireWire cards that support the 1394a 400MBS protocol used with the Pyrocam III. In newer Laptops with only ExpressCard slots, a 1394b 800MBS ExpressCard Adapter...
NanoModeScan is perhaps the most versatile of the available instruments for measuring M2 , since it can be used with lasers of any wavelength and power level. Nonetheless, with this versatility comes the complexity of selecting the proper test lens with which to make the measurements. There are several considerations to be taken into account.
With the broad range of wavelengths that can be measured with this instrument, the first consideration is the material and anti-reflective coating of the lens. There are a number of lenses that are...
Scanning slit profilers (such as Ophir’s NanoScan) boast several advantageous qualitites, such as the ability to measure high powers without attenuation, relatively inexpensive infrared compatibility, and more.
But whenever someone mentions pulsed beams, there’s always a pause. Well, what’s your pulse frequency? Beam width? What kind of accuracy are you looking for?
Why can’t I...
One of the differences between a CCD and slit scanning beam profiler is the lower limit of beam size measurement. A CCD is limited to around 10 pixels for an accurate beam measurement. With the current CCD technology, this means that a CCD can measure a beam of approximately 40-50um diameter. A scanning slit profiler is known for being able to measure smaller beams—but just how small?
If an infinitely narrow slit is scanned across a Gaussian beam, the light intensity transmitted by the slit as it moves across the beam will exactly map...
BeamGage produces five different types of files. All use industry standard formats. The list of file types and their naming extensions are as follows:
The .bgData file format contains the processed image output from BeamGage. The .bgData file formatting follows standard HDF5 formatting rules. The HDF5 format is compatible with many third party applications, one of which...
The Focal Length Divergence measurement method is based upon the beam width of a focused beam’s spot size and the focal length of the focusing optic.
The Focal Length Divergence method provides a means for finding the far-field beam divergence at any point in the beam propagation path. As shown below, the calculation performed by the...