 Download Data Sheet. |
 | Spiricon has been the world leader in the manufacture of pyroelectric solidstate detector arrays and cameras. For over 25 years the Pyrocam™ has been the overwhelming camera of choice for Laser Beam Diagnostics of IR and UV lasers and high temperature thermal imaging. Precision, stability, reliability, and versatility have become its proud heritage.
The Pyrocam™ III offers easy Windows ® camera setup, direct Windows quantitative and image display, 14 bit digitizer, versatile Firewire® PC interface, an integral chopper for CW beams and thermal imaging, and many other enhanced features. |
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| The Pyrocam™ III camera creates clear and illuminating images of your laser beam profile. Displayed in 2D or 3D views, you can immediately recognize beam characteristics that affect laser performance and operation. This instantly alerts you to detrimental laser variations. Instantaneous feedback enables timely correction and real-time tuning of laser parameters including laser alignment. For example, when an industrial shop foreman saw the CO2 laser beam profile in Figure 1 he knew immediately why that laser was not processing materials the same as the other shop lasers, with the profile shown in Figure 2. |  |  |
| Fig. 1. Industrial CO2 laser performing inconsistent processing. | Fig. 2. Industrial CO2 laser performing specifed processing. |
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| The Pyrocam™ III measures the beam profile of both pulsed and CW lasers. Since the pyroelectric crystal is an integrating sensor, pulses from femtosecond to 12.8ms can be measured. The pyroelectric crystal only measures changes in intensity, and so is relatively immune to ambient temperature changes. Because CW laser beams must be chopped to create a changing signal, the Pyrocam™ III contains an integral chopper as an option. |
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| Spiricon’s Pyrocam™ III pyroelectric camera is an excellent tool for measuring THz lasers and sources. The coating of the crystal absorbs all wavelengths including 1um to over 3000um (0.1THz to 300THz). For THz sources the sensitivity of the Pyrocam™ III is relatively low, at about 300mW/cm2 at full output. With a S/N of 1000, beams of 30mW/cm2 are easily visible. In addition, with Spiricon’s patented Ultracal baseline setting, multiple frames can be summed to “pull” a signal out of the noise. Summing 256 frames enables viewing of beams as low as 1-2mW/cm2. |
| With Terahertz research suddenly being a central topic of interest, the Pyrocam™ III becomes an invaluable aid in this exciting research. Otherwise, scientists working on Terahertz research had no easy way to characterize the profile, or energy distribution, of their lasers or sources. |
| THz laser beam at 0.2THz (1.55mm) 3mW input power; 19 frames summed. |
| The Pyrocam™ III detector array has a very broadband coating which enables operation at essentially all IR and UV laser wavelengths. The curve ends at 100nm in the UV, but X-ray operation has been observed. Likewise the curve ends at 100μm in the far IR, but the camera has been used at >3000μm. |
Thus you can use the Pyrocam™ III in the near IR for Nd:YAG lasers at 1.06μm, and for infrared fiber optics at 1.3μm and 1.55μm. Use the Pyrocam™ III for HF/DF lasers near 4μm and for Optical Parametric Oscillators from 1 μm to 10μm. It measures Free Electron Lasers between 10μm and 3000μm.
The Pyrocam™ III is extremely useful in the UV from 355nm to 157nm for Excimer lasers and for tripled or quadrupled Nd:YAG lasers. The detector is stable under UV illumination, without the deterioration experienced by CCD cameras. (The pyroelectric detector operates in the visible spectrum, and can see the alignment HeNe used with CO2 lasers. However, spurious response from the underlying silicon multiplexer creates undesirable performance, and the camera is not recommended for quantitative visible measurements). | 
Fig. 6. Spectral response of Pyrocam™ III detector array (without window). |
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| Er:YAG laser at 2.9µm. | Output of infrared fiber optic. | THz laser beam at 1.6THz (184um). | Free Electron laser at 100µm. |
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| The Pyrocam™ III Windows application incorporates setup software to control all functions of the camera, such as pulsed versus chopped operation, gain, and background reference subtraction, eliminating all controls from the camera housing. |
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| Pyrocam III Windows setup menu. |
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| A Windows viewer application enables viewing of the laser beam in a number of modes, including 3D isometric plots, 2D color contour plots, and gray scale for thermal imaging. This application enables stand-alone operation of the camera independent of any other software. Nevertheless, the Spiricon LBA-PC beam analysis software provides many additional features and capabilities not incorporated with the camera. |
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| Composite Excimer LASIK beam profile at 193nm. | Composite Excimer LASIK beam profile in 2D display. |
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| The Pyrocam™ III consists of a LiTa03 pyroelectric crystal mounted with indium bumps to a solid-state readout multiplexer. This sensor, developed for the Pyrocam I, has proven to be the most rugged, stable, and precise IR detector array available. Light impinging on the pyroelectric crystal is absorbed and converted to heat, which creates charge on the surface. The multiplexer then reads out this charge onto the video line. For use with short laser pulses, the firmware of the camera creates a very short electronic shutter to accurately capture the thermally generated signal. |
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| Pyrocam III sensor array and window assembly |
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| The camera features a 14 bit A/D converter which digitizes deep into the camera noise. This enables reliable measurement and analysis of both large signals and low level signals in the wings of the laser beam. Fourteen bit digitizing also enables accurate signal summing and averaging to pull weak signals out of noise. This is especially useful with fiber optics at 1.3μm and 1.55μm, and in thermal imaging. |
| The Pyrocam™ III camera electronics incorporates 2 Firewire® (IEEE 1394A) interface ports. Multiple Pyrocam IIIs can be daisy chained together using the 1394 cabling. |
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| The Pyrocam™ III incorporates a new compact housing measuring only 5.5” high by 5.1” wide, and 2.5” deep in the direction of the beam path. This allows the camera to be inserted into smaller spaces on the optical table. It also makes the camera useful as a portable camera for thermal imaging and on-site field service of laser systems. The Pyrocam III integral focal plane chopper helps keep the camera head compact. |
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| The Pyrocam™ III is an ideal camera for use in scientific laboratory investigation of laser beams. This includes physics, chemistry, and electronic system designs. As an example, the photos below show a research CO2 laser and a research Nd:YAG laser, both with cavity misalignment. The camera is also useful in product engineering of CO2 and other infrared lasers. The Pyrocam™ III is an integral part of the assembly lines of many CO2 laser manufacturers. Integrators of systems are using the Pyrocam™ sensor to make sure that optical systems are aligned and operating properly. |
| There are many medical applications of the Pyrocam™ III, such as the analysis of excimer lasers used for eye surgery. In many cases these lasers need alignment to ensure that the eye surgery is performed as expected. Other medical IR lasers perform dermatology, for which the uniformity of the beam profile must be assured. Fiber optic communications, at 1.3μm and 1.55μm make significant use of the Pyrocam™ III for analyzing the beams being emitted, as well as analyzing properties of the beams before launching them into fibers. The greater stability of the Pyrocam™ III make it a good choice over other cameras operating at telecommunication wavelengths. |
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| CO2 laser with cavity misalignment. | Nd:YAG laser with cavity misalignment. |
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| CO2 laser with cavity misalignment. | Nd:YAG laser with cavity misalignment. |
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| The Pyrocam™ III is becoming an essential tool in the maintenance of industrial infrared lasers, especially CO2. The Pyrocam™ III replaces non-electronic mode burns and acrylic blocks by providing higher definition electronic recording of data, and analysis of short term fluctuations. The Pyrocam™ III is superior to other electronic methods of measuring CO2 lasers in that the entire beam can be measured in a single pulse, and additional measurements made in real-time. This ensures that the beam did not change during the measurement. |
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| The Pyrocam™ III sensor is capable of operation with intensities about 106 greater than CCD cameras. This makes the camera ideal for use with high power lasers, as less attenuation is required. Nevertheless, pulsed lasers with fluence too high can evaporate the absorbing front electrode. |
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| As shown the damage threshold increases with pulse width. With nanosecond and longer pulses, detector saturation occurs before damage. With shorter pulses it helps to increase the camera amplifier gain so that electronic saturation occurs before damage. |
| The sensor can be damaged by excessive CW power, which causes crystal cracking. Very few Pyrocam III detectors have been damaged by CW power, but some have been ablated by high peak pulse energy. |
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