多光谱照相机

Ricoh has developed a multi-spectroscopic camera that can acquire 2D spectral information as well as chromaticity and other color information for a subject in real-time. And it’s all packaged in a unique configuration similar in size to an ordinary FA camera.

Multi-spectroscopic camera features

多光谱相机可以从被摄体获取光谱信息。虽然使用可交换滤色器和棱镜的系统已被确立为获取光谱信息的常规技术，但使用可交换滤色器的系统交换时间对实时成像构成了障碍。另一方面，使用棱镜很难使相机更紧凑。

理光多光谱相机使用光学设备，可以在一个单一的快照中获取多个光谱信息，以及图像处理技术，为每个光谱信息生成一个图像。因此，可以实时计算特定波长的光谱分布和色度。这使得精确地获取所需的光谱信息成为可能。此外，光谱信息可以通过与传统工厂自动化（FA）相机尺寸相似的设备获得。除了检测难以区分的物体外，我们的多光谱相机还可用于检测状态随时间变化的物体和检测异物。除了FA，可能的应用还包括食品、制药、农业和安全行业。

技术概述

The new multi-spectroscopic cameras developed by Ricoh incorporate the following three technologies:
- A color filter that extracts plural spectral information from an object
- A microlens array that distributes the plural spectral information onto sensor pixels
- An image processor that generates an image for each spectral information from the sensor image
然后根据以这种方式获得的复数光谱信息计算光谱和色度（参见图1）。

在理光多光谱相机中，来自一个物体点的光通过具有不同光谱特性的滤光片，每一个光在传感器上的不同位置形成一个图像。这使得在单次拍摄中获得二维光谱图像成为可能。理光的光学和图像处理技术的融合使多重光谱信息能够在二维和一次拍摄中获得。

Figure 1: Multi-spectroscopic camera configuration

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Types of multi-spectroscopic camera

根据光谱滤光片的特性，多光谱相机可用于1）多光谱相机、2）二维彩色分析仪和3）多波段相机。
1) Multispectral cameras can obtain continuous spectral information (such as luminescence emission spectrum and spectral reflectivity) of the subject by using a spectral filter having continuous wavelengths.
2) A 2D (two-dimensional) color analyzer can extract accurate color information of the subject by using a spectral filter having sensitivity same as the human eye. The 2D color analyzer has merits compared to the ordinary RGB color camera on that the analyzer can sense colors exactly the human sees and that colors can be managed by chromaticity which is defined by the international standard.
3) A multiband camera can spectrally analyze the specified wavelengths according to application. By specifying the band beforehand, the camera can be customized.

Multi-spectroscopic camera applications

多光谱相机和二维彩色分析仪

Usage scenario: color inspection

By computing chromaticity, it becomes possible to conduct high-precision color inspections that outperform previous color photograph imaging inspections in which certain color determinations are impossible.

该技术可用于LCD、OLED或其他发光显示器的颜色检测。通过使用传统的点颜色检查器，需要执行多次拍摄和测量以检查整个屏幕。与此相反，您可以使用多光谱相机或2D颜色分析器（见图2A、2B）仅用一次拍摄来执行显示器的颜色检查。对于多光谱相机，您还可以从测量的光谱分布图（图2C）一次检查显示器的发光特性。

This technology can also be used for color inspections of molded or painted products with color limit samples (see Figure 4). Up to now, you needed to check physical objects and color limit samples by sight alternately many of times. By using the multispectral camera or the 2D color analyzer, the color relations between physical object and color limit samples become clear by a chromaticity diagram. So color inspections become easy (see Figure 3A, 3B).

图：2C

Figure 2A shows the image captured by a multispectral camera or a 2D color analyzer, taking a display which represents 6 color patches.　Square shapes in Figure 2A are the areas to be measured, and chromaticity in each square shape is plotted at the chromaticity diagram (See Figure 2B). Also, regarding the multispectral camera, each spectrum distribution is shown by graph (See Figure 2C).

图3显示的颜色inspections using color limit samples. Upper 3 samples are color limit samples of the object color, and under 2 samples are measuring samples. When the right measuring sample of the under 2 samples is NG, chromaticity of the NG sample is displayed as a red patch in contrast to gray patches corresponding to the chromaticity of the 3 color limit samples as shown in Figure 3B.

Figure 4: Color inspection usage scenario

Multiband camera

使用场景：状态感知

The state of a subject (freshness, purity, disease severity) can be quantitatively evaluated in ways that were not possible with previous color photography. By capturing specified spectral images of individual subjects, the sweetness of produce and the freshness of food can be quantitatively evaluated from information derived from minute differences in color.

Since the spectrum function of this camera is collected in the exclusive lens, it can respond to broad applications and used with only one camera by exchanging the exclusive lens.

Figure 5: State awareness usage scenario

排序依据：field“Machine Vision”