PURPOSE: To provide a sample detection device by which the images of samples whose magnifications are different from each other can be simultaneously obtained.

CONSTITUTION: Light made incident from the sample is passed through an objective lens 41 and split into three optical paths by beam splitters 42 and 43. The light split by the splitter 42 is reflected on a mirror 44 and passed through a convex lens 45a. Then, the image thereof is pickedup as the high- magnification image by a TV camera 14a. The light advancing through the beamsplitters 42 and 43 is made incident on a TV camera 14b and detected as the middle-magnification image. The light split by the splitter 43 is reflected on a mirror 46 and passed through a concave lens 47b. Besides, it is made incident on a TV camera 14c and detected as the low-magnification image.