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标准标定工具套装 Standard calibration target set with protective carrying case

 

 

 

2D标定概述 / 2D Calibration Overview

2d-calibration1

VIC-2D系统的标定过程是非常快速和简单的。 在VIC-2D软件中点击Calibration选项下的“Calibration Scale”按钮即可轻松完成。 当需要绝对尺度的信息时,则必须通过包含已知距离点的图像来参照标定,比如表面制作了已知距离的标志点的试件图像,或者与试件位于同一平面的标尺、标定板靶的图像等等。 这时您只需选择一个对应的尺度单位(如毫米,英寸等)来代替像素作为度量单位。 在使用VIC-3D的标定板靶作为已知距离标定参照时,精度可以达到子像素级。

The process of calibrating a VIC-2D system is quick and simple.  The procedure is software based and can be performed quite easily by clicking the “Calibrate Scale” button under the Calibration option in the VIC-2D program.  To calibrate for scale, you must have an image which contains a known distance, either marked on the specimen or on a ruler or target that is in the same plane as the specimen.  Here, you simply choose a dimension (mm, inches, etc.) to replace pixels as a form of measurement.  If a VIC-3D calibration target is used to define the known distance, subpixel accuracy can be achieved.

 

 

3D标定概述 / 3D Calibration Overview

3D Calibration

VIC-3D系统的标定相当简捷,已经优化到了近乎自动的过程。 该系统的标定只需在3D相机系统前随意移动和偏转刚性的标定板靶进行成像,然后再做分析即可。 标定过程会精确计算图像采集器的内在和外在参数,同时获得图像采集系统的三角测量定位关系并移除镜头的光学畸变。 这最终消除了所有测量偏差,并在试件表面定义了一个3D坐标系。 整个过程典型耗时只需1-3分钟

Calibrating a VIC-3D system is straightforward and has been streamlined to a nearly automatic process. The procedure for the 3D system involves moving, imaging, and analyzing a rigid calibration target in front of a stereo camera pair. This precisely calculates the cameras’ intrinsic and extrinsic parameters while triangulating the cameras’ positions and removing lens distortions.  This ultimately removes any measurement bias and defines a three-dimensional coordinate system on the specimen’s surface.  This entire process typically takes 1-3 minutes.

 

 

标定板靶概述 / Calibration target Overview

CSI公司提供了多种类型的标定板靶,如标准板靶,双面板靶,玻璃板靶,显微镜板靶和红外板靶。 每个标定板靶都对应于不同类型的应用与视场。 要了解更多有关您的应用所需的板靶点阵类型信息,请阅读我们在下面列出并描述的这些板靶的各项功能、用途和对应系统。

There are many types of calibration targets available at Correlated Solutions, such as Standard Targets, Double Sided Targets, Glass Targets, Microscope Targets, and IR Targets.  Each calibration target is needed for a different type of application and/or field of view.  To find out more information on the type of gird you have or need for your application, we have listed and described each of these target’s features, purposes, and corresponding systems below.

 

 

标准标定板靶 / The Standard Calibration Target (30mm+)

Standard Grid

每个VIC-3D™系统都配备了标准标定板靶套件,覆盖30mm及以上的视场。每块板靶都具有超哑光表面,以及坚固耐用的设计,它们不同规格间特有的可识别编码点还可实现VIC-3D v7及更高版本中的自动间距检测功能。这些板靶可用于高速、低速系统以及高分辨率、低分辨率相机的标定。如果需要精确的标定板靶检定,CSI公司还提供美国国家标准与技术研究院(NIST)的可追溯证书,提供详细的点阵间距参数测量报告。

The Standard Calibration Target set is provided with each VIC-3D™ System and covers fields of view from 30mm and up.  Each target features an ultra matte finish, a rigid & durable design, and they are specially coded for automatic spacing detection in VIC-3D v7 and later.  These targets can be used for calibrating high-speed and low-speed systems and for both high and low resolution cameras.  If exact calibration target measurements are needed, Correlated Solutions’ can provide NIST traceable certificates which provide detailed measurements on spacing parameters.

当您遇到特殊应用尺寸的板靶或需要更换板靶时怎么办?CSI赋予了用户自制标定板的能力。用户友好的标靶生成器可以从这里下载:cal_gen.exe(7MB)。 用户自行打印的板靶必须使用高分辨率激光打印机,并且确保平面度与平整度,更重要的是使用高刚性板材来制作。

Need to replace a target?  Users have the ability to create their own standard calibration targets.  The user friendly Calibration Target Generator can be downloaded here: cal_gen.exe (7MB).  Self-printed targets must utilize a high-resolution laser printer, and must be adhere to a flat, but more importantly, rigid plate.

 

 

大尺度标定 / Large Scale Calibrations (2m+)

CSI公司制造的最大标定板靶(36“x 24”)可以标定大到2米的视场。 而需要标定更大的视场时,则单个板靶技术将不再适用(刚性不足)或制造成本高昂。 为了解决这个问题,CSI公司采用了一种被称为“外部定向标定”的智能标定技术。这是一种两步标定技术,首先用一个小的标准标定板靶单独标定每个相机,然后使用试件表面上的已知距离为尺度标定。 这为一个最初看起来很严重的问题提供了一个非常准确又成本低廉且实用的解决方案。 这项技术也证明了VIC-3D产品的稳健性和标定程序的灵活性。

The largest target (36″ x 24″) made by Correlated Solutions calibrates a field of view up to about two meters.  If calibrating a larger field of view is required, a single target is no longer practical to use or cost effective to produce.  To handle this problem, Correlated Solutions has implemented an intelligent calibration technique called “External Orientation Calibration.”  This is a two step technique that first calibrates each camera individually with a small standard calibration target, and then uses a known distance on the specimen’s surface to calibrate for scale.  This provides a very accurate, low cost, and practical solution to what may initially seem like a “large” problem.  Implementing this technique demonstrates the robustness of VIC-3D products and the flexibility of the calibration procedure.

 

 

双面标定板靶 / Double Sided Targets (35mm – 1.5m)

FCP_ABC

FCP_EFG双面板靶是用来同时标定彼此相对向的两个VIC-3D系统。 该板靶允许将面对面安装的两个DIC系统的数据相对容易地置于同一坐标系中。 当您的应用需要测量同一试件的两面以分析厚度或颈缩时,双面板靶可以简化标定和建立坐标系过程。

A double sided target is used to simultaneously calibrate two VIC-3D systems facing each other. The target allows DIC data from oppositely mounted systems to be put into a common coordinate system with relative ease. When your application requires the measurement of two sides of the same specimen to analyze thickness or necking, a double sided target simplifies the calibration process.

双面板靶的制造方式与标准标定板靶非常相似,可确保在多种测试环境下的超哑光表面、高刚性及耐用性。 它们也在CSI总部被单独标定,以确保测量的精确性。

Double sided targets are manufactured in much the same way as standard calibration targets to ensure an ultra-matte finish and high rigidity & durability for a multitude of testing environments.  They are also individually calibrated at CSI’s headquarters to ensure accurate measurements are achieved.

 

 

 玻璃板靶概述 / Glass Target Overview

1-Inch-Grid

当标定视场小于30mm时,标准标定板靶将不再适用。这是由于标准板靶的制造设备的打印分辨率已不能满足小尺度圆点阵所需的精度。 此外,当视场小于30毫米时对,标准板靶的成像也很困难,缺少能够帮助板靶在成像过程中进行姿态倾斜和旋转的必要硬件。

When calibrating fields of view smaller than 30mm, standard calibration targets are no longer ideal to use.  This is due to the fact that printing devices limit the size of the elliptical markers printed with acceptable resolution.  Furthermore, imaging standard targets at fields of view smaller than 30mm can also prove difficult with no other hardware to provide assistance during the tilt and rotation process.

为实现从0.7毫米到30毫米的小尺度标定,CSI公司提供了由激光蚀刻、蓝色镀铬的钠钙玻璃材质的标定板靶。 所有的玻璃靶材都是通过照相平版印刷工艺制造的,这种工艺会在玻璃板的表面形成蓝色镀铬层。 配合适当的背光照明,这些板靶点阵会具有非常清晰锐利的边沿轮廓,这些边沿在高倍放大时仍十分清晰,并且与外部硬件(如板靶固定装置和鹅颈定位臂)兼容。 由于在较高的光学放大倍数下导致的成像景深减小,需要这些外部硬件帮助保持板靶小平面的稳定性并控制其倾斜范围不超出景深。

For small scale calibrations from 0.7mm to 30mm, Correlated Solutions provides laser etched, blue chrome plated, sodalime glass calibration targets.  All glass targets are created through a photo lithography process which creates a plating of blue chrome over the face of the glass plate.  With proper backlighting, these targets provide very sharp edges which are clearly seen at high magnifications and are compatible with external hardware, such as target fixtures and gooseneck positioning arms.  Since depth of fields decrease at higher magnifications, external hardware is almost always necessary for stabilizing the target for small out-of-plane tilts.

 

 

小尺度标定 / Small Scale Calibrations (8mm – 30mm)

4-in-1 Glass Grid Assembly

 

VIC-3D标准光学系统应用于视场范围为8mm-30mm的测量时,CSI提供的两个玻璃板靶中总有一个能够满足需求,无论是1“板靶可用的20mm-30mm视场、还是4合1板靶(左视图 )可用的8mm-20mm视场。

For fields of view from 8mm-30mm on a VIC-3D system with standard optics, one of two glass targets should be used, either the 1″ Target for fields of view 20mm-30mm or the 4-in-1 Target (seen left) for fields of view 8mm-20mm.

这两块板靶通常一起交付给用户,并且如在左侧看到的该组件照片所示,这还包括鹅颈定位臂、迷你球头铰链和玻璃靶座。标定小视场时,配合使用这些组件能够保持标定过程的稳定性和灵活性

Both targets are generally provided together and with the assembly seen on the left, which includes a gooseneck positioning arm, a mini-ball head, and a glass target holder.  Using these components together will ensure both stability and flexibility when calibrating small fields of view.

如果试件是7mm 或更小,虽然标准系统仍可以使用, 但是, 用户应该更多的考虑使用VIC-3D显微测量系统, 这样可以最大化利用相机分辨素, 以最大限度地提高您试验可获得的潜在数据点数量。
 

If the sample is 7mm or smaller a standard system can be used, however, a microscope system should be heavily considered in order to take advantage of camera resolution to maximize your test’s potential data points.

 

 

显微标定板靶 / Microscope Calibration Target (0.7mm – 7mm)

Microscope Grids

对于0.7毫米至7毫米的视场测量,这时需要使用VIC-3D显微系统来实现。 标定显微镜系统与标定标准系统类似,但尺度更小。 显微镜系统为这些小尺度视场测量同时提供了左侧图示的两个板靶。 显微镜上还配置了含背光照明的板靶固定装置,以确保标定过程中从板靶的第一次到最后一次的每次偏转都能顺利拍照。

For fields of view from 0.7mm to 7mm, the VIC-3D Microscope system will be needed.  Calibrating the Microscope System is similar to calibrating a standard system, but on an even smaller scale.  Both of the targets seen to the left are provided with the microscope system for these fields of view.  A back-lit target fixture is also provided on the microscope to ensure the calibration process goes smoothly from the first tilt to the last.

Speckled Glass Grid2由于复杂的光学路径和高光学放大倍率,该标定过程中需要采取额外的步骤来完全消除显微镜系统中的光学畸变。 在显微镜下进行三维DIC测量时,CSI的这项独家专利过程非常重要。 没有它,测量偏差约为2000微应变。 而这一过程中,需要拍摄散斑玻璃板靶的一系列图像。 通过使用VIC-3D专利的畸变修正功能分析这些图像组,然后计算并修正所有光学畸变。 利用精密的电动3轴工作台,这个独有的光学失真修正步骤成为了一个自动化的过程,节省了时间并进一步简化了标定步骤。

Due to a complex optical path and high magnification, one additional step needs to be taken in the calibration procedure to completely remove optical distortions from the microscope system.  This exclusive patented procedure is essential when performing three-dimension DIC under a microscope.  Without it, the measurement bias is on the order of 2,000 microstrain.  In this step, a sequence of images is taken of a speckled glass target.  By analyzing these image groups with VIC-3D’s patented Distortion Correction feature, all distortions are then computed and corrected.  With the motorized 3-axis precision stage, this additional Distortion Sequence becomes an automated process, saving time and further simplifying the calibration process.

 

 

红外标定板靶 / IR Calibration Target s (50mm – 300mm)

18mm glass IR calibration grid

如果您的应用需要同步全场温度测量以及应变和变形测量,新的VIC-3D IR™系统可能会让您感兴趣。 如果您想将此功能添加到现有系统中,则只需添加这些硬件:红外相机,镜头和红外标定板靶。

If your application requires full-field temperature measurements alongside strain and deformation measurements, the new VIC-3D IR™ System may be of interest to you.  If you’d like to add this capability to an existing system, only a couple pieces of hardware need to be added: a camera, lens, and calibration target(s).

要将红外温度场相机标定到VIC-3D系统中,需要在红外温度场相机工作的波长范围内和DIC相机工作的白光范围内均可见的标定板靶。 最简单的方法是使用稍微加热的镀铬玻璃板靶或激光蚀刻阳极氧化铝板靶。 镀铬玻璃板靶用于标定较小的视场,而激光蚀刻铝板则用于标定更大的视场。

To calibrate a thermal camera into the VIC-3D system, a calibration target visible in the thermal camera’s wavelength range and in the DIC cameras’ white light range is needed.  The easiest way to achieve this is to use a slightly heated chrome plated glass target or a laser-etched, anodized, aluminum target.  The chrome plated glass targets are used to calibrate smaller fields of view and the laser etched aluminum plates are used to calibrate larger fields of view.

每个红外标定板靶都有自己的保护外套。 保护外套或板靶标识有板靶的标定参数,例如点距(mm)、点数x、点数y、x偏移量、y偏移量、x长度和y长度。

Each IR calibration target comes with its own protective case.  The case or target displays the target’s calibration parameters, such as pitch (mm), number of dots in x, number of dots in y, offset in x, offset in y, length in x, and length in y.