全息和干涉测量
全息术是一种产生三维图像的技术。该技术需要一种波长
固定且辐射谱线宽度较窄的激光器。在干涉术中，通过
叠加两个电磁波来产生图像模式，然后对其进行测量，
以提取有关波本身或与一个或两个波相互作用的材料
的有用信息。
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Holography is a three-dimensional imaging technique produced and reconstructed using a laser light source. This technique is particularly useful in a diverse range of applications and markets, from interferometric microscopy to data storage processing, from anti-counterfeit measures for currency, credit cards, and personal identification documents to projection displays for the arts and entertainment industry. Conventional 2D imaging may also use enhanced holographic techniques to preview building projects or product concepts. Holography requires a single light source to both illuminate an object as well as imprint on a substrate. IPG produces compact and cost-effective fiber laser sources for holographic applications, such as CW single frequency fiber lasers, (GLR, YLR-SF and ELR-SF), fiber amplifiers (YAR-LP-SF and EAR-LP-SF), as well as CW single-frequency Mid-IR lasers, CL-SF and CLT-SF. Typical bandwidths of IPG single frequency lasers are in the kHz to MHz range (coherence length of kilometers to 100s of meters). IPG single frequency lasers offer more power in a compact package as compared to traditional solid state or ion gas sources. The higher power of IPG lasers also generates faster holographic images. |
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From spectroscopy to remote sensing, from mechanical and optical metrology to oceanography and seismology, from quantum mechanics to nuclear and plasma physics, the range of interferometry applications is extremely broad. To accommodate the broad spectrum of applications, IPG produces a diverse range of continuous wave and pulsed lasers most suitable for interferometric measurements. These lasers fall into two major categories: 1) single-frequency CW lasers such as 1-100 W fiber lasers and fiber-pumped hybrid lasers and 2) Mid-IR ultrafast mode-locked lasers.
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| One example of an interferometric measurement used for non-destructive characterization of materials in mechanical engineering is shearography, a method similar to holographic interferometry. It is widely used in production and development in aerospace, wind rotor blades, automotive, and materials development and testing research. Shearography uses coherent light for nondestructive testing of materials, strain measurement, and vibration analysis. Advantages of shearography are high area throughput, non-contact interrogation, relative insensitivity to environmental disturbances, and good performance on honeycomb materials. |  |