A natural color scanning electron microscopy image

A method for obtaining a scanning electron microscopy (SEM) image with natural color information (NCSEM image) has been developed by using an SEM operated under low vacuum or low voltage, a video microscope (VM), and a high-performance personal computer. In order to produce an NCSEM image with both the fine structures of the SEM image and the color information included in the VM image, an improvement of the depth of focus in VM image is required. This can be successfully performed by some digital image processing techniques. A difference in resolution between the SEM image and the VM image does not disturb our study as shown in the text. In addition, the well-known hue, saturation, intensity (HSI) color model, which is frequently utilized for color image manipulation, was originally altered for the present purpose.