LUMOS II

什么是FTIR成像?

什么是 FTIR 成像?

化学成像通常是一种非常有效的工具,可以根据样品的光谱特性进行非常详细的、空间分辨的化学分析,然后将样品的光谱性质表示为化学图像。

化学图像的每个像素由整个 FTIR 光谱组成。通过对该光谱数据的解析,可以渲染伪彩色图像以强调和表征样品的属性,如化学结构或组成。

有几种方法可以创建所述图像。单点和线阵列测量可以生成化学图像,但焦平面阵列 (FPA) 技术在光谱呈现和性能方面更胜一筹。

什么使 FPA 成像更胜一筹?

原则上,您可以在测量点之间进行小距离的连续单点测量并以此创建样品的化学图像。这可以满足许多应用需求。但是,使用此方法分析较大的样品区域需要花费大量时间。幸运的是,全自动 LUMOS II 最大限度地减少了所需的工作量。 

与 FPA 和单元测量相比,线阵列检测器更倾向于是一种混合解决方案。在这种方案中,单元件检测器被串联排列(例如1×8)并同时报告一系列光谱(线性扫描)。这一系列光谱被“缝合”以获得化学图像。 相比之下,FPA检测器在每次测量时产生限定样品区域的真实化学图像。可以合并这些FPA图像对非常大的样品区域进行成像。

FPA Imaging LUMOS II

虽然线阵列可能比单点测量生成结果更快,但在光谱质量和处理方面存在很大的折衷。此外,这种情况下的 ATR 成像几乎是不可能的,只有在理想化配件下才可行。这意味着在这些情况下,化学和视觉图像永远无法正确对齐。

这通常会导致关键样品信息的丢失。更糟糕的是,根据其性质和结构,一些样品甚至不适合于上述扫描方法。

焦平面阵列检测器基本上没有上述限制。它通过单次测量(LUMOS 1024 光谱)记录大量数据来生成化学图像。无论样品结构如何,速度如何惊人,化学图像都能与视觉图像完美对齐。

 

Bruker(布鲁克)的目标是实现完美的成像效果,这就是为什么我们在 LUMOS II 中使用了最新的焦平面阵列检测器技术。

LUMOS II 在 FPA 成像中的优势:

  • 最高成像性能:在任何测量模式下,FPA成像均以高空间分辨率同时采集 1024 个光谱
  • 与单点或线阵测量相比,具有无与伦比的空间分辨能力
  • 基于FPA成像和系统的高度自动化,LUMOS II可用于分析非常大的样品区域
  • FPA 成像可在最短的时间内以最高清晰度生成化学图像
  • 添加多达两个额外的检测器以保持分析的灵活性,并可从众多可用的检测器中进行选择

需要深入了解 FTIR 光谱和成像技术,才能提供最佳的分析设备。简单的软件、智能硬件和巧妙的自动化使您在 FTIR 化学成像方面具有优势。

结论:

FPA 技术在速度和空间分辨率方面显著优于线阵列和单点测量。此外,FPA技术具有无限的适用性,所获得的光谱数据始终具有最高品质,并且测量时间在技术允许范围内尽可能短。

[Bitte nach "Chinese (Simplified)" übersetzen:] 1. What is chemical imaging?

Chemical imaging is a method for spatially resolving the chemical properties of a sample in 2D or 3D images. With this technique it is possible to obtain information about the material properties, the structure and the origin of the examined samples.

 

2. What is FTIR imaging?

FTIR imaging is one way to create said spatially resolved chemical images. Each pixel of these images consists of a whole IR spectrum. By interpreting the individual spectra, interesting sample regions can be detected and evaluated.

 

3. How do you create FTIR images?

Common methods are sequential single point or line array measurements, as well as the direct acquisition of 2D images by a focal-plane array (FPA) detector. While FPA detectors offer the superior solution, highly automated single-point measurements are an economical alternative.

 

4. How does an FPA detector work?

The principle of an FPA detector is analogous to that of a digital camera. Instead of visible light, however, a defined array of pixels is illuminated by infrared light, with each detector pixel recording an independent, spatially resolved IR spectrum. 

 

5. Do FPA detectors require apertures?

No, an FPA detector does not require any apertures. Each pixel of the detector functions as an aperture and thus records a spatially IR information directly. This allows much faster and higher resolution measurements compared other detector techniques.

 

6. Is it possible to adjust the spatial resolution of an FPA?

The spatial resolution of an FPA detector depends on the size of the individual detector pixels. However, adjacent pixels can be combined to form a "larger pixel" and thus the spatial resolution is reduced, also improving spectral quality.

 

7. Are there different FPA sizes?

FPA detectors are available in different array sizes. Size should be selected according to the optical system (microscope). For example, the LUMOS II is optimized for a 32x32 pixel array, while the HYPERION 3000 is designed for a 64x64 or 128x128 pixel arrays. With the latter it is possible to record an impressive number of more than 16,000 spatially resolved spectra in one scan.

 

8. Is a larger FPA better?

No, because the size of the FPA detector depends exclusively on the optimal illumination provided by the microscope. A homogeneous illumination of the detector array is important to ensure a consistently high spectral sensitivity both in the center and at the edges of the detector.

 

9. When does a larger FPA have advantages?

The larger the FPA detector area, the more spectra are recorded simultaneously. Since the spatial resolution is independent of the array size, this means that a 128x128 FPA detector covers an area 16 times larger than a 32x32 detector array in a single measurement.

 

10. Can FPA be combined with any measurement technique?

Yes they can. FPA detectors offer advantages in transmission, reflection and attenuated total reflection (ATR). Especially when used with ATR technology, this type of detector achieves an exceptionally high spatial resolution.

 

11. Why is the resolution of FPA measurements in ATR increased?

The combination of a high refractive solid-state lens (germanium ATR crystal) and an "aperture-free" FPA detector increases spatial resolution by a factor of 4 compared to transmission measurements. This effect is also called an immersion lens.

 

12. Are FPA measurements applicable to all samples?

Since FPA measurements can be combined with all measurement techniques, in principle all types of samples can be analyzed this way. Gases, liquids and other volatile substances cannot be analyzed microscopically due to their kinetic properties.

 

13. What are typical applications of an FPA?

Typical applications can be found in all areas of industry and research. Starting with the analysis of microplastics, particles and contaminations over the characterization of complex chemical structures, such as biological tissue, pharmaceutical products up to multilayer laminates and lacquers. In short, this detector technology is used wherever very high spatial resolution and the analysis of large sample areas are indispensable.