Frank Opett 2015-02-24 00:19:41
As micro-manufacturing technology continues to enable machining and printing of ever-smaller devices and mechanisms, measurement of these tiny parts becomes more complex. Smaller feature sizes and tighter tolerances demand higher measurement accuracy and precision for quality control applications. Non-contact optical measuring systems are ideal for measuring microparts, and the latest optical technologies are geared to the unique requirements posed by very small feature sizes. Although traditional zoom optical measuring systems have their place in manufacturing quality control, they are not always ideal for micro-manufacturing. Zoom systems typically offer a fairly wide range of magnification to accommodate the variety of parts and features that come up in day to day operations. Often, the highest magnification available in a zoom system is barely enough to measure very small features accurately and repeatably. For many zoom lens systems, measurement at the highest magnification involves compromises in lighting, focus quality and image sharpness that can degrade measurement repeatability. For high performance micro-part measurement, true “micro” optical technology is needed. Magnification, field of view, depth of field, working distance and resolution are design variables in any Optical system. In addition, illuminators and metrology cameras are also designed to work as a system along with the imaging optics to suit the typical part measurement requirements. When the aim is accurate imaging of very small parts and features, the optics must offer sufficient magnification to easily “see” the features, and a small enough depth of field to focus accurately and provide a sharp image to the camera. Fixed lens optical systems offer specific advantages over zoom optical systems for micro-measuring applications. The optical setup can be precisely configured to the specific measurement application. Typically, the front objective lens is the main determinant of magnification, and since these objective lenses are easily interchangeable, there is flexibility in setting the magnification, working distance and depth of field for the situation, while still enjoying the higher performance and simplicity of fixed lens optics. Higher magnification lenses typically provide a smaller depth of field, providing focus sensitivity and sharper images. Fixed lens systems typically have lower distortion than their zoom lens counterparts, and their resolution can be paired more closely with the metrology camera’s pixel size to ensure no loss of image resolution. Spark and SparkMVP high performance systems from RAM Optical Instrumentation are compact and reliable measurement platforms, and are offered exclusively with a high resolution fixed lens optical system to provide the precision needed for micro-manufacturing quality control. With a variety of objective lenses to choose from, Spark and SparkMVP can be configured for your specific Measurement application, and their three standard light sources provide optimal illumination of ultrafine parts and features. With the integration of QVI® Measure-X®, the world’s most popular metrology software, Spark and SparkMVP fixed lens systems can provide high accuracy and precision for your most complex applications.
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